diff --git a/.eslintrc.json b/.eslintrc.json
index d132ee3..26d041a 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -10,5 +10,18 @@
     "ecmaVersion": "latest",
     "sourceType": "module"
   },
-  "rules": {}
+  "rules": {
+    "n/no-unpublished-import": [
+      "error",
+      {
+        "allowModules": ["diff"]
+      }
+    ],
+    "n/no-extraneous-import": [
+      "error",
+      {
+        "allowModules": ["colors"]
+      }
+    ]
+  }
 }
diff --git a/.gitignore b/.gitignore
index 40b878d..9cf6fff 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
-node_modules/
\ No newline at end of file
+node_modules/
+.idea
diff --git a/.nmvrc b/.nmvrc
new file mode 100644
index 0000000..6f7f377
--- /dev/null
+++ b/.nmvrc
@@ -0,0 +1 @@
+v16
diff --git a/package-lock.json b/package-lock.json
index 46d9bcd..a6d7206 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -12,6 +12,7 @@
         "css-tree": "^2.3.1"
       },
       "devDependencies": {
+        "diff": "^5.1.0",
         "eslint": "^8.50.0",
         "eslint-plugin-import": "^2.28.1",
         "eslint-plugin-n": "^16.0.1",
@@ -20,7 +21,7 @@
         "prettier-plugin-packagejson": "^2.4.5"
       },
       "engines": {
-        "node": "^14.13.0 || >=15.0.0"
+        "node": "^10 || ^12.20.0 || ^14.13.0 || >=15.0.0"
       }
     },
     "node_modules/@aashutoshrathi/word-wrap": {
@@ -540,12 +541,6 @@
         "node": ">=10"
       }
     },
-    "node_modules/builtins/node_modules/yallist": {
-      "version": "4.0.0",
-      "resolved": "https://registry.npmjs.org/yallist/-/yallist-4.0.0.tgz",
-      "integrity": "sha512-3wdGidZyq5PB084XLES5TpOSRA3wjXAlIWMhum2kRcv/41Sn2emQ0dycQW4uZXLejwKvg6EsvbdlVL+FYEct7A==",
-      "dev": true
-    },
     "node_modules/bundle-name": {
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/bundle-name/-/bundle-name-3.0.0.tgz",
@@ -792,6 +787,15 @@
         "url": "https://github.com/sponsors/sindresorhus"
       }
     },
+    "node_modules/diff": {
+      "version": "5.1.0",
+      "resolved": "https://registry.npmjs.org/diff/-/diff-5.1.0.tgz",
+      "integrity": "sha512-D+mk+qE8VC/PAUrlAU34N+VfXev0ghe5ywmpqrawphmVZc1bEfn56uo9qpyGp1p4xpzOHkSW4ztBd6L7Xx4ACw==",
+      "dev": true,
+      "engines": {
+        "node": ">=0.3.1"
+      }
+    },
     "node_modules/dir-glob": {
       "version": "3.0.1",
       "resolved": "https://registry.npmjs.org/dir-glob/-/dir-glob-3.0.1.tgz",
@@ -1151,12 +1155,6 @@
         "node": ">=10"
       }
     },
-    "node_modules/eslint-plugin-n/node_modules/yallist": {
-      "version": "4.0.0",
-      "resolved": "https://registry.npmjs.org/yallist/-/yallist-4.0.0.tgz",
-      "integrity": "sha512-3wdGidZyq5PB084XLES5TpOSRA3wjXAlIWMhum2kRcv/41Sn2emQ0dycQW4uZXLejwKvg6EsvbdlVL+FYEct7A==",
-      "dev": true
-    },
     "node_modules/eslint-plugin-unicorn": {
       "version": "48.0.1",
       "resolved": "https://registry.npmjs.org/eslint-plugin-unicorn/-/eslint-plugin-unicorn-48.0.1.tgz",
@@ -1228,12 +1226,6 @@
         "node": ">=10"
       }
     },
-    "node_modules/eslint-plugin-unicorn/node_modules/yallist": {
-      "version": "4.0.0",
-      "resolved": "https://registry.npmjs.org/yallist/-/yallist-4.0.0.tgz",
-      "integrity": "sha512-3wdGidZyq5PB084XLES5TpOSRA3wjXAlIWMhum2kRcv/41Sn2emQ0dycQW4uZXLejwKvg6EsvbdlVL+FYEct7A==",
-      "dev": true
-    },
     "node_modules/eslint-scope": {
       "version": "7.2.2",
       "resolved": "https://registry.npmjs.org/eslint-scope/-/eslint-scope-7.2.2.tgz",
@@ -3759,6 +3751,12 @@
       "integrity": "sha512-l4Sp/DRseor9wL6EvV2+TuQn63dMkPjZ/sp9XkghTEbV9KlPS1xUsZ3u7/IQO4wxtcFB4bgpQPRcR3QCvezPcQ==",
       "dev": true
     },
+    "node_modules/yallist": {
+      "version": "4.0.0",
+      "resolved": "https://registry.npmjs.org/yallist/-/yallist-4.0.0.tgz",
+      "integrity": "sha512-3wdGidZyq5PB084XLES5TpOSRA3wjXAlIWMhum2kRcv/41Sn2emQ0dycQW4uZXLejwKvg6EsvbdlVL+FYEct7A==",
+      "dev": true
+    },
     "node_modules/yocto-queue": {
       "version": "0.1.0",
       "resolved": "https://registry.npmjs.org/yocto-queue/-/yocto-queue-0.1.0.tgz",
@@ -4141,12 +4139,6 @@
           "requires": {
             "lru-cache": "^6.0.0"
           }
-        },
-        "yallist": {
-          "version": "4.0.0",
-          "resolved": "https://registry.npmjs.org/yallist/-/yallist-4.0.0.tgz",
-          "integrity": "sha512-3wdGidZyq5PB084XLES5TpOSRA3wjXAlIWMhum2kRcv/41Sn2emQ0dycQW4uZXLejwKvg6EsvbdlVL+FYEct7A==",
-          "dev": true
         }
       }
     },
@@ -4319,6 +4311,12 @@
       "integrity": "sha512-qE3Veg1YXzGHQhlA6jzebZN2qVf6NX+A7m7qlhCGG30dJixrAQhYOsJjsnBjJkCSmuOPpCk30145fr8FV0bzog==",
       "dev": true
     },
+    "diff": {
+      "version": "5.1.0",
+      "resolved": "https://registry.npmjs.org/diff/-/diff-5.1.0.tgz",
+      "integrity": "sha512-D+mk+qE8VC/PAUrlAU34N+VfXev0ghe5ywmpqrawphmVZc1bEfn56uo9qpyGp1p4xpzOHkSW4ztBd6L7Xx4ACw==",
+      "dev": true
+    },
     "dir-glob": {
       "version": "3.0.1",
       "resolved": "https://registry.npmjs.org/dir-glob/-/dir-glob-3.0.1.tgz",
@@ -4678,12 +4676,6 @@
           "requires": {
             "lru-cache": "^6.0.0"
           }
-        },
-        "yallist": {
-          "version": "4.0.0",
-          "resolved": "https://registry.npmjs.org/yallist/-/yallist-4.0.0.tgz",
-          "integrity": "sha512-3wdGidZyq5PB084XLES5TpOSRA3wjXAlIWMhum2kRcv/41Sn2emQ0dycQW4uZXLejwKvg6EsvbdlVL+FYEct7A==",
-          "dev": true
         }
       }
     },
@@ -4733,12 +4725,6 @@
           "requires": {
             "lru-cache": "^6.0.0"
           }
-        },
-        "yallist": {
-          "version": "4.0.0",
-          "resolved": "https://registry.npmjs.org/yallist/-/yallist-4.0.0.tgz",
-          "integrity": "sha512-3wdGidZyq5PB084XLES5TpOSRA3wjXAlIWMhum2kRcv/41Sn2emQ0dycQW4uZXLejwKvg6EsvbdlVL+FYEct7A==",
-          "dev": true
         }
       }
     },
@@ -6457,6 +6443,12 @@
       "integrity": "sha512-l4Sp/DRseor9wL6EvV2+TuQn63dMkPjZ/sp9XkghTEbV9KlPS1xUsZ3u7/IQO4wxtcFB4bgpQPRcR3QCvezPcQ==",
       "dev": true
     },
+    "yallist": {
+      "version": "4.0.0",
+      "resolved": "https://registry.npmjs.org/yallist/-/yallist-4.0.0.tgz",
+      "integrity": "sha512-3wdGidZyq5PB084XLES5TpOSRA3wjXAlIWMhum2kRcv/41Sn2emQ0dycQW4uZXLejwKvg6EsvbdlVL+FYEct7A==",
+      "dev": true
+    },
     "yocto-queue": {
       "version": "0.1.0",
       "resolved": "https://registry.npmjs.org/yocto-queue/-/yocto-queue-0.1.0.tgz",
diff --git a/package.json b/package.json
index 4660bb3..87f71ab 100644
--- a/package.json
+++ b/package.json
@@ -4,6 +4,7 @@
   "type": "module",
   "main": "index.js",
   "scripts": {
+    "add-syntax": "node testing/add-syntax.js",
     "eslint": "eslint --fix .",
     "prettier-check": "prettier --check .",
     "prettier-format": "prettier --write .",
@@ -15,6 +16,7 @@
     "css-tree": "^2.3.1"
   },
   "devDependencies": {
+    "diff": "^5.1.0",
     "eslint": "^8.50.0",
     "eslint-plugin-import": "^2.28.1",
     "eslint-plugin-n": "^16.0.1",
@@ -23,6 +25,6 @@
     "prettier-plugin-packagejson": "^2.4.5"
   },
   "engines": {
-    "node": "^14.13.0 || >=15.0.0"
+    "node": "^10 || ^12.20.0 || ^14.13.0 || >=15.0.0"
   }
 }
diff --git a/query-syntax.js b/query-syntax.js
index 97e87e6..ccff22d 100644
--- a/query-syntax.js
+++ b/query-syntax.js
@@ -67,8 +67,18 @@ function addToConstructMap(map, list) {
   }
 }
 
+function appendPropertyNewValues(list) {
+  for (const item of list) {
+    const property = properties.get(item.name);
+    if (property && item.newValues) {
+      property.value += ` | ${item.newValues}`;
+    }
+  }
+}
+
 function extractDataFromSpec(spec) {
   addToConstructMap(properties, spec.properties);
+  appendPropertyNewValues(spec.properties);
   addToConstructMap(atrules, spec.atrules);
   addToConstructMap(selectors, spec.selectors);
 
@@ -111,9 +121,6 @@ function getTypesForSyntaxes(syntaxes, typesToOmit, constituents) {
     if (node.type === "Type" && !constituents.includes(node.name)) {
       constituents.push(node.name);
     }
-    /* if (node.type === "Function" && !constituents.includes(node.name)) {
-      constituents.push(node.name);
-    } */
   }
 
   for (const syntax of syntaxes) {
@@ -121,13 +128,16 @@ function getTypesForSyntaxes(syntaxes, typesToOmit, constituents) {
       const ast = definitionSyntax.parse(syntax);
       definitionSyntax.walk(ast, processNode);
     } catch (e) {
-      console.log("error parsing syntax: ", syntax);
+      console.log("error parsing syntax: ", syntax, e);
     }
   }
 }
 
 function getValue(name) {
-  return functions.get(`${name}()`) || types.get(name) || values.get(name);
+  if (name.includes("()")) {
+    return functions.get(name);
+  }
+  return types.get(name) || values.get(name);
 }
 
 /**
@@ -174,7 +184,9 @@ export function getConstituentSyntaxes(itemSyntax, typesToOmit) {
       if (constituentSyntaxEntry && constituentSyntaxEntry.value) {
         constituentSyntaxes.push(constituentSyntaxEntry.value);
       } else if (constituentSyntaxEntry && constituentSyntaxEntry.values) {
-        constituentSyntaxes.push(constituentSyntaxes.values);
+        constituentSyntaxes.push(
+          ...constituentSyntaxEntry.values.map((v) => v.value)
+        );
       }
     }
   }
@@ -189,7 +201,8 @@ export function getConstituentSyntaxes(itemSyntax, typesToOmit) {
       syntaxes.push({
         type: constituent,
         syntax:
-          valueEntry.value || valueEntry.values.map((v) => v.name).join(" | "),
+          valueEntry.value ||
+          valueEntry.values.map((v) => `<${v.name}>`).join(" | "),
       });
     }
   }
@@ -210,7 +223,7 @@ export function getSyntax(name, type, typesToOmit) {
 
   switch (type) {
     case "property":
-      syntax = properties.get(name)?.value;
+      syntax = properties.has(name) ? properties.get(name).value : undefined;
       break;
     case "type":
       if (name.endsWith(">")) {
diff --git a/testing/add-syntax.js b/testing/add-syntax.js
new file mode 100644
index 0000000..ad746a1
--- /dev/null
+++ b/testing/add-syntax.js
@@ -0,0 +1,41 @@
+/*
+  This script updates syntax for given CSS feature and type in test data.
+*/
+
+/* eslint-disable-next-line n/no-unsupported-features/node-builtins */
+import fs from "node:fs/promises";
+import * as Utils from "./utils.js";
+
+const helpMessage =
+  "Usage:\n\t" +
+  "npm run add-syntax '[feature-name]' '[feature-type]'\n\t" +
+  "node testing/add-syntax '[feature-name]' '[feature-type]'\n";
+
+if (process.argv.length < 3) {
+  console.error(helpMessage);
+  /* eslint-disable-next-line no-process-exit, n/no-process-exit */
+  process.exit(1);
+} else if (process.argv[2] === "--help" || process.argv[2] === "-h") {
+  console.info(helpMessage);
+  /* eslint-disable-next-line no-process-exit, n/no-process-exit */
+  process.exit(0);
+}
+
+const name = process.argv[2];
+const type = process.argv[3];
+let syntax = Utils.getSyntaxForType(name, type);
+
+if (syntax) {
+  syntax = {
+    name: name,
+    type: type,
+    ...syntax,
+  };
+
+  await fs.writeFile(
+    `testing/data/${type}__${name}.json`,
+    JSON.stringify(syntax, undefined, "  ")
+  );
+}
+
+console.log(`Added ${type}__${name}`);
diff --git a/testing/check-syntaxes.js b/testing/check-syntaxes.js
index cb1ef79..bbf9a90 100644
--- a/testing/check-syntaxes.js
+++ b/testing/check-syntaxes.js
@@ -1,5 +1,30 @@
+/*
+  This script tests all the syntaxes in test data against syntaxes returend by the current code.
+*/
+
+/* eslint-disable-next-line n/no-unsupported-features/node-builtins */
 import fs from "node:fs/promises";
 import * as Utils from "./utils.js";
+import * as Diff from "diff";
+/* eslint-disable-next-line no-unused-vars */
+
+function logDiff(oldString, newString) {
+  const diff = Diff.diffLines(oldString, newString);
+
+  for (const part of diff) {
+    let prefix = "";
+    if (part.added) {
+      prefix = "+";
+    } else if (part.removed) {
+      prefix = "-";
+    }
+    let value = prefix + part.value.replaceAll("\n", "\n" + prefix);
+    value = value.replace(/[+-]$/gm, "");
+    process.stdout.write(value);
+  }
+
+  console.log("\n----");
+}
 
 const errors = [];
 let total = 0;
@@ -20,6 +45,8 @@ for await (const filePath of Utils.walkSync("testing/data")) {
       );
 
       if (oldSyntax !== newSyntax) {
+        console.warn(`${data.name} ${data.type}`);
+        logDiff(oldSyntax, newSyntax);
         errors.push(`${data.name} ${data.type}`);
       }
     } catch (e) {
diff --git a/testing/data/@counter-style.json b/testing/data/@counter-style.json
deleted file mode 100644
index 718c4e0..0000000
--- a/testing/data/@counter-style.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "@counter-style",
-  "type": "at-rule",
-  "syntax": "@counter-style <counter-style-name> { <declaration-list> }",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/@counter-style__fallback.json b/testing/data/@counter-style__fallback.json
deleted file mode 100644
index 5d0f649..0000000
--- a/testing/data/@counter-style__fallback.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "fallback",
-  "type": "at-rule-descriptor",
-  "syntax": "<counter-style-name>",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/@counter-style__speak-as.json b/testing/data/@counter-style__speak-as.json
deleted file mode 100644
index 57aa11a..0000000
--- a/testing/data/@counter-style__speak-as.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "speak-as",
-  "type": "at-rule-descriptor",
-  "syntax": "auto | bullets | numbers | words | spell-out | <counter-style-name>",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/@counter-style__system.json b/testing/data/@counter-style__system.json
deleted file mode 100644
index 220b288..0000000
--- a/testing/data/@counter-style__system.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "system",
-  "type": "at-rule-descriptor",
-  "syntax": "cyclic | numeric | alphabetic | symbolic | additive | [fixed <integer>?] | [ extends <counter-style-name> ]",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/@font-feature-values__font-display.json b/testing/data/@font-feature-values__font-display.json
deleted file mode 100644
index a5e21d4..0000000
--- a/testing/data/@font-feature-values__font-display.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "font-display",
-  "type": "at-rule-descriptor",
-  "syntax": "auto | block | swap | fallback | optional",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/@font-palette-values__font-family.json b/testing/data/@font-palette-values__font-family.json
deleted file mode 100644
index c8200a8..0000000
--- a/testing/data/@font-palette-values__font-family.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "font-family",
-  "type": "at-rule-descriptor",
-  "syntax": "<family-name>",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/angle-percentage.json b/testing/data/angle-percentage.json
deleted file mode 100644
index 7a61ac3..0000000
--- a/testing/data/angle-percentage.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "angle-percentage",
-  "type": "type",
-  "syntax": "[ <angle> | <percentage> ]",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/animation-delay.json b/testing/data/animation-delay.json
deleted file mode 100644
index c52b42f..0000000
--- a/testing/data/animation-delay.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "animation-delay",
-  "type": "property",
-  "syntax": "<time>#",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/@counter-style__additive-symbols.json b/testing/data/at-rule-descriptor__additive-symbols.json
similarity index 100%
rename from testing/data/@counter-style__additive-symbols.json
rename to testing/data/at-rule-descriptor__additive-symbols.json
diff --git a/testing/data/@font-face__ascent-override.json b/testing/data/at-rule-descriptor__ascent-override.json
similarity index 100%
rename from testing/data/@font-face__ascent-override.json
rename to testing/data/at-rule-descriptor__ascent-override.json
diff --git a/testing/data/@font-palette-values__base-palette.json b/testing/data/at-rule-descriptor__base-palette.json
similarity index 100%
rename from testing/data/@font-palette-values__base-palette.json
rename to testing/data/at-rule-descriptor__base-palette.json
diff --git a/testing/data/@font-face__descent-override.json b/testing/data/at-rule-descriptor__descent-override.json
similarity index 100%
rename from testing/data/@font-face__descent-override.json
rename to testing/data/at-rule-descriptor__descent-override.json
diff --git a/testing/data/at-rule-descriptor__fallback.json b/testing/data/at-rule-descriptor__fallback.json
new file mode 100644
index 0000000..529fcfb
--- /dev/null
+++ b/testing/data/at-rule-descriptor__fallback.json
@@ -0,0 +1,11 @@
+{
+  "name": "fallback",
+  "type": "at-rule-descriptor",
+  "syntax": "<counter-style-name>",
+  "constituents": [
+    {
+      "type": "counter-style-name",
+      "syntax": "<decimal> | <decimal-leading-zero> | <arabic-indic> | <armenian> | <upper-armenian> | <lower-armenian> | <bengali> | <cambodian> | <khmer> | <cjk-decimal> | <devanagari> | <georgian> | <gujarati> | <gurmukhi> | <hebrew> | <kannada> | <lao> | <malayalam> | <mongolian> | <myanmar> | <oriya> | <persian> | <lower-roman> | <upper-roman> | <tamil> | <telugu> | <thai> | <tibetan> | <lower-alpha> | <lower-latin> | <upper-alpha> | <upper-latin> | <lower-greek> | <hiragana> | <hiragana-iroha> | <katakana> | <katakana-iroha> | <disc> | <circle> | <square> | <disclosure-open> | <disclosure-closed> | <cjk-earthly-branch> | <cjk-heavenly-stem> | <korean-hangul-formal> | <korean-hanja-informal> | <korean-hanja-formal> | <ethiopic-numeric>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/@font-face__font-display.json b/testing/data/at-rule-descriptor__font-display.json
similarity index 100%
rename from testing/data/@font-face__font-display.json
rename to testing/data/at-rule-descriptor__font-display.json
diff --git a/testing/data/@font-face__font-family.json b/testing/data/at-rule-descriptor__font-family.json
similarity index 100%
rename from testing/data/@font-face__font-family.json
rename to testing/data/at-rule-descriptor__font-family.json
diff --git a/testing/data/@font-face__font-feature-settings.json b/testing/data/at-rule-descriptor__font-feature-settings.json
similarity index 100%
rename from testing/data/@font-face__font-feature-settings.json
rename to testing/data/at-rule-descriptor__font-feature-settings.json
diff --git a/testing/data/@font-face__font-stretch.json b/testing/data/at-rule-descriptor__font-stretch.json
similarity index 100%
rename from testing/data/@font-face__font-stretch.json
rename to testing/data/at-rule-descriptor__font-stretch.json
diff --git a/testing/data/@font-face__font-style.json b/testing/data/at-rule-descriptor__font-style.json
similarity index 53%
rename from testing/data/@font-face__font-style.json
rename to testing/data/at-rule-descriptor__font-style.json
index 7df1d65..2bc3de8 100644
--- a/testing/data/@font-face__font-style.json
+++ b/testing/data/at-rule-descriptor__font-style.json
@@ -2,5 +2,10 @@
   "name": "font-style",
   "type": "at-rule-descriptor",
   "syntax": "auto | normal | italic | oblique [ <angle>{1,2} ]?",
-  "constituents": []
+  "constituents": [
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    }
+  ]
 }
\ No newline at end of file
diff --git a/testing/data/@font-face__font-variation-settings.json b/testing/data/at-rule-descriptor__font-variation-settings.json
similarity index 100%
rename from testing/data/@font-face__font-variation-settings.json
rename to testing/data/at-rule-descriptor__font-variation-settings.json
diff --git a/testing/data/@font-face__font-weight.json b/testing/data/at-rule-descriptor__font-weight.json
similarity index 100%
rename from testing/data/@font-face__font-weight.json
rename to testing/data/at-rule-descriptor__font-weight.json
diff --git a/testing/data/@property__inherits.json b/testing/data/at-rule-descriptor__inherits.json
similarity index 100%
rename from testing/data/@property__inherits.json
rename to testing/data/at-rule-descriptor__inherits.json
diff --git a/testing/data/@property__initial-value.json b/testing/data/at-rule-descriptor__initial-value.json
similarity index 100%
rename from testing/data/@property__initial-value.json
rename to testing/data/at-rule-descriptor__initial-value.json
diff --git a/testing/data/@font-face__line-gap-override.json b/testing/data/at-rule-descriptor__line-gap-override.json
similarity index 100%
rename from testing/data/@font-face__line-gap-override.json
rename to testing/data/at-rule-descriptor__line-gap-override.json
diff --git a/testing/data/@counter-style__negative.json b/testing/data/at-rule-descriptor__negative.json
similarity index 100%
rename from testing/data/@counter-style__negative.json
rename to testing/data/at-rule-descriptor__negative.json
diff --git a/testing/data/@font-palette-values__override-colors.json b/testing/data/at-rule-descriptor__override-colors.json
similarity index 97%
rename from testing/data/@font-palette-values__override-colors.json
rename to testing/data/at-rule-descriptor__override-colors.json
index ba54922..db55867 100644
--- a/testing/data/@font-palette-values__override-colors.json
+++ b/testing/data/at-rule-descriptor__override-colors.json
@@ -95,6 +95,10 @@
       "type": "colorspace-params",
       "syntax": "[ <predefined-rgb-params> | <xyz-params>]"
     },
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    },
     {
       "type": "predefined-rgb-params",
       "syntax": "<predefined-rgb> [ <number> | <percentage> | none ]{3}"
diff --git a/testing/data/@counter-style__pad.json b/testing/data/at-rule-descriptor__pad.json
similarity index 100%
rename from testing/data/@counter-style__pad.json
rename to testing/data/at-rule-descriptor__pad.json
diff --git a/testing/data/@page__page-orientation.json b/testing/data/at-rule-descriptor__page-orientation.json
similarity index 100%
rename from testing/data/@page__page-orientation.json
rename to testing/data/at-rule-descriptor__page-orientation.json
diff --git a/testing/data/@counter-style__prefix.json b/testing/data/at-rule-descriptor__prefix.json
similarity index 100%
rename from testing/data/@counter-style__prefix.json
rename to testing/data/at-rule-descriptor__prefix.json
diff --git a/testing/data/@counter-style__range.json b/testing/data/at-rule-descriptor__range.json
similarity index 100%
rename from testing/data/@counter-style__range.json
rename to testing/data/at-rule-descriptor__range.json
diff --git a/testing/data/@font-face__size-adjust.json b/testing/data/at-rule-descriptor__size-adjust.json
similarity index 100%
rename from testing/data/@font-face__size-adjust.json
rename to testing/data/at-rule-descriptor__size-adjust.json
diff --git a/testing/data/@page__size.json b/testing/data/at-rule-descriptor__size.json
similarity index 100%
rename from testing/data/@page__size.json
rename to testing/data/at-rule-descriptor__size.json
diff --git a/testing/data/at-rule-descriptor__speak-as.json b/testing/data/at-rule-descriptor__speak-as.json
new file mode 100644
index 0000000..ef5b33f
--- /dev/null
+++ b/testing/data/at-rule-descriptor__speak-as.json
@@ -0,0 +1,11 @@
+{
+  "name": "speak-as",
+  "type": "at-rule-descriptor",
+  "syntax": "auto | bullets | numbers | words | spell-out | <counter-style-name>",
+  "constituents": [
+    {
+      "type": "counter-style-name",
+      "syntax": "<decimal> | <decimal-leading-zero> | <arabic-indic> | <armenian> | <upper-armenian> | <lower-armenian> | <bengali> | <cambodian> | <khmer> | <cjk-decimal> | <devanagari> | <georgian> | <gujarati> | <gurmukhi> | <hebrew> | <kannada> | <lao> | <malayalam> | <mongolian> | <myanmar> | <oriya> | <persian> | <lower-roman> | <upper-roman> | <tamil> | <telugu> | <thai> | <tibetan> | <lower-alpha> | <lower-latin> | <upper-alpha> | <upper-latin> | <lower-greek> | <hiragana> | <hiragana-iroha> | <katakana> | <katakana-iroha> | <disc> | <circle> | <square> | <disclosure-open> | <disclosure-closed> | <cjk-earthly-branch> | <cjk-heavenly-stem> | <korean-hangul-formal> | <korean-hanja-informal> | <korean-hanja-formal> | <ethiopic-numeric>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/@font-face__src.json b/testing/data/at-rule-descriptor__src.json
similarity index 100%
rename from testing/data/@font-face__src.json
rename to testing/data/at-rule-descriptor__src.json
diff --git a/testing/data/@counter-style__suffix.json b/testing/data/at-rule-descriptor__suffix.json
similarity index 100%
rename from testing/data/@counter-style__suffix.json
rename to testing/data/at-rule-descriptor__suffix.json
diff --git a/testing/data/@counter-style__symbols.json b/testing/data/at-rule-descriptor__symbols.json
similarity index 100%
rename from testing/data/@counter-style__symbols.json
rename to testing/data/at-rule-descriptor__symbols.json
diff --git a/testing/data/@property__syntax.json b/testing/data/at-rule-descriptor__syntax.json
similarity index 100%
rename from testing/data/@property__syntax.json
rename to testing/data/at-rule-descriptor__syntax.json
diff --git a/testing/data/at-rule-descriptor__system.json b/testing/data/at-rule-descriptor__system.json
new file mode 100644
index 0000000..22d55ae
--- /dev/null
+++ b/testing/data/at-rule-descriptor__system.json
@@ -0,0 +1,11 @@
+{
+  "name": "system",
+  "type": "at-rule-descriptor",
+  "syntax": "cyclic | numeric | alphabetic | symbolic | additive | [fixed <integer>?] | [ extends <counter-style-name> ]",
+  "constituents": [
+    {
+      "type": "counter-style-name",
+      "syntax": "<decimal> | <decimal-leading-zero> | <arabic-indic> | <armenian> | <upper-armenian> | <lower-armenian> | <bengali> | <cambodian> | <khmer> | <cjk-decimal> | <devanagari> | <georgian> | <gujarati> | <gurmukhi> | <hebrew> | <kannada> | <lao> | <malayalam> | <mongolian> | <myanmar> | <oriya> | <persian> | <lower-roman> | <upper-roman> | <tamil> | <telugu> | <thai> | <tibetan> | <lower-alpha> | <lower-latin> | <upper-alpha> | <upper-latin> | <lower-greek> | <hiragana> | <hiragana-iroha> | <katakana> | <katakana-iroha> | <disc> | <circle> | <square> | <disclosure-open> | <disclosure-closed> | <cjk-earthly-branch> | <cjk-heavenly-stem> | <korean-hangul-formal> | <korean-hanja-informal> | <korean-hanja-formal> | <ethiopic-numeric>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/@font-face__unicode-range.json b/testing/data/at-rule-descriptor__unicode-range.json
similarity index 100%
rename from testing/data/@font-face__unicode-range.json
rename to testing/data/at-rule-descriptor__unicode-range.json
diff --git a/testing/data/@color-profile.json b/testing/data/at-rule__@color-profile.json
similarity index 100%
rename from testing/data/@color-profile.json
rename to testing/data/at-rule__@color-profile.json
diff --git a/testing/data/@container.json b/testing/data/at-rule__@container.json
similarity index 100%
rename from testing/data/@container.json
rename to testing/data/at-rule__@container.json
diff --git a/testing/data/at-rule__@counter-style.json b/testing/data/at-rule__@counter-style.json
new file mode 100644
index 0000000..0bbe023
--- /dev/null
+++ b/testing/data/at-rule__@counter-style.json
@@ -0,0 +1,11 @@
+{
+  "name": "@counter-style",
+  "type": "at-rule",
+  "syntax": "@counter-style <counter-style-name> { <declaration-list> }",
+  "constituents": [
+    {
+      "type": "counter-style-name",
+      "syntax": "<decimal> | <decimal-leading-zero> | <arabic-indic> | <armenian> | <upper-armenian> | <lower-armenian> | <bengali> | <cambodian> | <khmer> | <cjk-decimal> | <devanagari> | <georgian> | <gujarati> | <gurmukhi> | <hebrew> | <kannada> | <lao> | <malayalam> | <mongolian> | <myanmar> | <oriya> | <persian> | <lower-roman> | <upper-roman> | <tamil> | <telugu> | <thai> | <tibetan> | <lower-alpha> | <lower-latin> | <upper-alpha> | <upper-latin> | <lower-greek> | <hiragana> | <hiragana-iroha> | <katakana> | <katakana-iroha> | <disc> | <circle> | <square> | <disclosure-open> | <disclosure-closed> | <cjk-earthly-branch> | <cjk-heavenly-stem> | <korean-hangul-formal> | <korean-hanja-informal> | <korean-hanja-formal> | <ethiopic-numeric>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/@font-face.json b/testing/data/at-rule__@font-face.json
similarity index 100%
rename from testing/data/@font-face.json
rename to testing/data/at-rule__@font-face.json
diff --git a/testing/data/@font-feature-values.json b/testing/data/at-rule__@font-feature-values.json
similarity index 100%
rename from testing/data/@font-feature-values.json
rename to testing/data/at-rule__@font-feature-values.json
diff --git a/testing/data/@font-palette-values.json b/testing/data/at-rule__@font-palette-values.json
similarity index 100%
rename from testing/data/@font-palette-values.json
rename to testing/data/at-rule__@font-palette-values.json
diff --git a/testing/data/@import.json b/testing/data/at-rule__@import.json
similarity index 100%
rename from testing/data/@import.json
rename to testing/data/at-rule__@import.json
diff --git a/testing/data/@keyframes.json b/testing/data/at-rule__@keyframes.json
similarity index 100%
rename from testing/data/@keyframes.json
rename to testing/data/at-rule__@keyframes.json
diff --git a/testing/data/@layer.json b/testing/data/at-rule__@layer.json
similarity index 100%
rename from testing/data/@layer.json
rename to testing/data/at-rule__@layer.json
diff --git a/testing/data/@media.json b/testing/data/at-rule__@media.json
similarity index 100%
rename from testing/data/@media.json
rename to testing/data/at-rule__@media.json
diff --git a/testing/data/@page.json b/testing/data/at-rule__@page.json
similarity index 100%
rename from testing/data/@page.json
rename to testing/data/at-rule__@page.json
diff --git a/testing/data/@property.json b/testing/data/at-rule__@property.json
similarity index 100%
rename from testing/data/@property.json
rename to testing/data/at-rule__@property.json
diff --git a/testing/data/@supports.json b/testing/data/at-rule__@supports.json
similarity index 100%
rename from testing/data/@supports.json
rename to testing/data/at-rule__@supports.json
diff --git a/testing/data/basic-shape__rect.json b/testing/data/basic-shape__rect.json
deleted file mode 100644
index 5f85711..0000000
--- a/testing/data/basic-shape__rect.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "rect",
-  "type": "function",
-  "syntax": "rect( <top>, <right>, <bottom>, <left> )",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/clip.json b/testing/data/clip.json
deleted file mode 100644
index 1e77571..0000000
--- a/testing/data/clip.json
+++ /dev/null
@@ -1,11 +0,0 @@
-{
-  "name": "clip",
-  "type": "property",
-  "syntax": "<rect()> | auto",
-  "constituents": [
-    {
-      "type": "rect()",
-      "syntax": "rect( <top>, <right>, <bottom>, <left> )"
-    }
-  ]
-}
\ No newline at end of file
diff --git a/testing/data/column-width.json b/testing/data/column-width.json
deleted file mode 100644
index 29ac998..0000000
--- a/testing/data/column-width.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "column-width",
-  "type": "property",
-  "syntax": "auto | <length [0,∞]>",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/counter.json b/testing/data/counter.json
deleted file mode 100644
index 7d9c73a..0000000
--- a/testing/data/counter.json
+++ /dev/null
@@ -1,35 +0,0 @@
-{
-  "name": "counter",
-  "type": "function",
-  "syntax": "counter( <counter-name>, <counter-style>? )",
-  "constituents": [
-    {
-      "type": "counter-style",
-      "syntax": "<counter-style-name> | <symbols()>"
-    },
-    {
-      "type": "symbols()",
-      "syntax": "symbols( <symbols-type>? [ <string> | <image> ]+ )"
-    },
-    {
-      "type": "symbols-type",
-      "syntax": "cyclic | numeric | alphabetic | symbolic | fixed"
-    },
-    {
-      "type": "image",
-      "syntax": "<url> | <gradient>"
-    },
-    {
-      "type": "url",
-      "syntax": "<url()> | <src()>"
-    },
-    {
-      "type": "url()",
-      "syntax": "url( <string> <url-modifier>* ) | <url-token>"
-    },
-    {
-      "type": "src()",
-      "syntax": "src( <string> <url-modifier>* )"
-    }
-  ]
-}
\ No newline at end of file
diff --git a/testing/data/counters.json b/testing/data/counters.json
deleted file mode 100644
index 55aea17..0000000
--- a/testing/data/counters.json
+++ /dev/null
@@ -1,35 +0,0 @@
-{
-  "name": "counters",
-  "type": "function",
-  "syntax": "counters( <counter-name>, <string>, <counter-style>? )",
-  "constituents": [
-    {
-      "type": "counter-style",
-      "syntax": "<counter-style-name> | <symbols()>"
-    },
-    {
-      "type": "symbols()",
-      "syntax": "symbols( <symbols-type>? [ <string> | <image> ]+ )"
-    },
-    {
-      "type": "symbols-type",
-      "syntax": "cyclic | numeric | alphabetic | symbolic | fixed"
-    },
-    {
-      "type": "image",
-      "syntax": "<url> | <gradient>"
-    },
-    {
-      "type": "url",
-      "syntax": "<url()> | <src()>"
-    },
-    {
-      "type": "url()",
-      "syntax": "url( <string> <url-modifier>* ) | <url-token>"
-    },
-    {
-      "type": "src()",
-      "syntax": "src( <string> <url-modifier>* )"
-    }
-  ]
-}
\ No newline at end of file
diff --git a/testing/data/filter-function__hue-rotate.json b/testing/data/filter-function__hue-rotate.json
deleted file mode 100644
index 26d03e7..0000000
--- a/testing/data/filter-function__hue-rotate.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "hue-rotate",
-  "type": "function",
-  "syntax": "hue-rotate( [ <angle> | <zero> ]? )",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/font-family.json b/testing/data/font-family.json
deleted file mode 100644
index 79d4828..0000000
--- a/testing/data/font-family.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "font-family",
-  "type": "property",
-  "syntax": "[ <family-name> | <generic-family> ]#",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/abs.json b/testing/data/function__abs.json
similarity index 100%
rename from testing/data/abs.json
rename to testing/data/function__abs.json
diff --git a/testing/data/acos.json b/testing/data/function__acos.json
similarity index 100%
rename from testing/data/acos.json
rename to testing/data/function__acos.json
diff --git a/testing/data/asin.json b/testing/data/function__asin.json
similarity index 100%
rename from testing/data/asin.json
rename to testing/data/function__asin.json
diff --git a/testing/data/atan.json b/testing/data/function__atan.json
similarity index 100%
rename from testing/data/atan.json
rename to testing/data/function__atan.json
diff --git a/testing/data/atan2.json b/testing/data/function__atan2.json
similarity index 100%
rename from testing/data/atan2.json
rename to testing/data/function__atan2.json
diff --git a/testing/data/attr.json b/testing/data/function__attr.json
similarity index 100%
rename from testing/data/attr.json
rename to testing/data/function__attr.json
diff --git a/testing/data/filter-function__blur.json b/testing/data/function__blur.json
similarity index 100%
rename from testing/data/filter-function__blur.json
rename to testing/data/function__blur.json
diff --git a/testing/data/filter-function__brightness.json b/testing/data/function__brightness.json
similarity index 100%
rename from testing/data/filter-function__brightness.json
rename to testing/data/function__brightness.json
diff --git a/testing/data/calc.json b/testing/data/function__calc.json
similarity index 100%
rename from testing/data/calc.json
rename to testing/data/function__calc.json
diff --git a/testing/data/clamp.json b/testing/data/function__clamp.json
similarity index 100%
rename from testing/data/clamp.json
rename to testing/data/function__clamp.json
diff --git a/testing/data/color_value__color-mix.json b/testing/data/function__color-mix.json
similarity index 100%
rename from testing/data/color_value__color-mix.json
rename to testing/data/function__color-mix.json
diff --git a/testing/data/color_value__color.json b/testing/data/function__color.json
similarity index 100%
rename from testing/data/color_value__color.json
rename to testing/data/function__color.json
diff --git a/testing/data/gradient__conic-gradient.json b/testing/data/function__conic-gradient.json
similarity index 95%
rename from testing/data/gradient__conic-gradient.json
rename to testing/data/function__conic-gradient.json
index 33ed98a..66edd3d 100644
--- a/testing/data/gradient__conic-gradient.json
+++ b/testing/data/function__conic-gradient.json
@@ -7,6 +7,10 @@
       "type": "conic-gradient-syntax",
       "syntax": "[ [ [ from <angle> ]? [ at <position> ]? ] || <color-interpolation-method> ]? , <angular-color-stop-list>"
     },
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    },
     {
       "type": "position",
       "syntax": "[ [ left | center | right ] || [ top | center | bottom ] | [ left | center | right | <length-percentage> ] [ top | center | bottom | <length-percentage> ]? | [ [ left | right ] <length-percentage> ] && [ [ top | bottom ] <length-percentage> ] ]"
diff --git a/testing/data/filter-function__contrast.json b/testing/data/function__contrast.json
similarity index 100%
rename from testing/data/filter-function__contrast.json
rename to testing/data/function__contrast.json
diff --git a/testing/data/cos.json b/testing/data/function__cos.json
similarity index 100%
rename from testing/data/cos.json
rename to testing/data/function__cos.json
diff --git a/testing/data/function__counter.json b/testing/data/function__counter.json
new file mode 100644
index 0000000..2a82716
--- /dev/null
+++ b/testing/data/function__counter.json
@@ -0,0 +1,39 @@
+{
+  "name": "counter",
+  "type": "function",
+  "syntax": "counter( <counter-name>, <counter-style>? )",
+  "constituents": [
+    {
+      "type": "counter-style",
+      "syntax": "<counter-style-name> | <symbols()>"
+    },
+    {
+      "type": "counter-style-name",
+      "syntax": "<decimal> | <decimal-leading-zero> | <arabic-indic> | <armenian> | <upper-armenian> | <lower-armenian> | <bengali> | <cambodian> | <khmer> | <cjk-decimal> | <devanagari> | <georgian> | <gujarati> | <gurmukhi> | <hebrew> | <kannada> | <lao> | <malayalam> | <mongolian> | <myanmar> | <oriya> | <persian> | <lower-roman> | <upper-roman> | <tamil> | <telugu> | <thai> | <tibetan> | <lower-alpha> | <lower-latin> | <upper-alpha> | <upper-latin> | <lower-greek> | <hiragana> | <hiragana-iroha> | <katakana> | <katakana-iroha> | <disc> | <circle> | <square> | <disclosure-open> | <disclosure-closed> | <cjk-earthly-branch> | <cjk-heavenly-stem> | <korean-hangul-formal> | <korean-hanja-informal> | <korean-hanja-formal> | <ethiopic-numeric>"
+    },
+    {
+      "type": "symbols()",
+      "syntax": "symbols( <symbols-type>? [ <string> | <image> ]+ )"
+    },
+    {
+      "type": "symbols-type",
+      "syntax": "cyclic | numeric | alphabetic | symbolic | fixed"
+    },
+    {
+      "type": "image",
+      "syntax": "<url> | <gradient>"
+    },
+    {
+      "type": "url",
+      "syntax": "<url()> | <src()>"
+    },
+    {
+      "type": "url()",
+      "syntax": "url( <string> <url-modifier>* ) | <url-token>"
+    },
+    {
+      "type": "src()",
+      "syntax": "src( <string> <url-modifier>* )"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/function__counters.json b/testing/data/function__counters.json
new file mode 100644
index 0000000..2ab63eb
--- /dev/null
+++ b/testing/data/function__counters.json
@@ -0,0 +1,39 @@
+{
+  "name": "counters",
+  "type": "function",
+  "syntax": "counters( <counter-name>, <string>, <counter-style>? )",
+  "constituents": [
+    {
+      "type": "counter-style",
+      "syntax": "<counter-style-name> | <symbols()>"
+    },
+    {
+      "type": "counter-style-name",
+      "syntax": "<decimal> | <decimal-leading-zero> | <arabic-indic> | <armenian> | <upper-armenian> | <lower-armenian> | <bengali> | <cambodian> | <khmer> | <cjk-decimal> | <devanagari> | <georgian> | <gujarati> | <gurmukhi> | <hebrew> | <kannada> | <lao> | <malayalam> | <mongolian> | <myanmar> | <oriya> | <persian> | <lower-roman> | <upper-roman> | <tamil> | <telugu> | <thai> | <tibetan> | <lower-alpha> | <lower-latin> | <upper-alpha> | <upper-latin> | <lower-greek> | <hiragana> | <hiragana-iroha> | <katakana> | <katakana-iroha> | <disc> | <circle> | <square> | <disclosure-open> | <disclosure-closed> | <cjk-earthly-branch> | <cjk-heavenly-stem> | <korean-hangul-formal> | <korean-hanja-informal> | <korean-hanja-formal> | <ethiopic-numeric>"
+    },
+    {
+      "type": "symbols()",
+      "syntax": "symbols( <symbols-type>? [ <string> | <image> ]+ )"
+    },
+    {
+      "type": "symbols-type",
+      "syntax": "cyclic | numeric | alphabetic | symbolic | fixed"
+    },
+    {
+      "type": "image",
+      "syntax": "<url> | <gradient>"
+    },
+    {
+      "type": "url",
+      "syntax": "<url()> | <src()>"
+    },
+    {
+      "type": "url()",
+      "syntax": "url( <string> <url-modifier>* ) | <url-token>"
+    },
+    {
+      "type": "src()",
+      "syntax": "src( <string> <url-modifier>* )"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/cross-fade.json b/testing/data/function__cross-fade.json
similarity index 100%
rename from testing/data/cross-fade.json
rename to testing/data/function__cross-fade.json
diff --git a/testing/data/color_value__device-cmyk.json b/testing/data/function__device-cmyk.json
similarity index 100%
rename from testing/data/color_value__device-cmyk.json
rename to testing/data/function__device-cmyk.json
diff --git a/testing/data/filter-function__drop-shadow.json b/testing/data/function__drop-shadow.json
similarity index 100%
rename from testing/data/filter-function__drop-shadow.json
rename to testing/data/function__drop-shadow.json
diff --git a/testing/data/element.json b/testing/data/function__element.json
similarity index 100%
rename from testing/data/element.json
rename to testing/data/function__element.json
diff --git a/testing/data/env.json b/testing/data/function__env.json
similarity index 100%
rename from testing/data/env.json
rename to testing/data/function__env.json
diff --git a/testing/data/exp.json b/testing/data/function__exp.json
similarity index 100%
rename from testing/data/exp.json
rename to testing/data/function__exp.json
diff --git a/testing/data/filter-function__grayscale.json b/testing/data/function__grayscale.json
similarity index 100%
rename from testing/data/filter-function__grayscale.json
rename to testing/data/function__grayscale.json
diff --git a/testing/data/color_value__hsl.json b/testing/data/function__hsl.json
similarity index 87%
rename from testing/data/color_value__hsl.json
rename to testing/data/function__hsl.json
index db3cdf8..0c0c74f 100644
--- a/testing/data/color_value__hsl.json
+++ b/testing/data/function__hsl.json
@@ -18,6 +18,10 @@
     {
       "type": "alpha-value",
       "syntax": "<number> | <percentage>"
+    },
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/function__hue-rotate.json b/testing/data/function__hue-rotate.json
new file mode 100644
index 0000000..9688676
--- /dev/null
+++ b/testing/data/function__hue-rotate.json
@@ -0,0 +1,11 @@
+{
+  "name": "hue-rotate",
+  "type": "function",
+  "syntax": "hue-rotate( [ <angle> | <zero> ]? )",
+  "constituents": [
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/color_value__hwb.json b/testing/data/function__hwb.json
similarity index 80%
rename from testing/data/color_value__hwb.json
rename to testing/data/function__hwb.json
index a12ab82..2dbd6b6 100644
--- a/testing/data/color_value__hwb.json
+++ b/testing/data/function__hwb.json
@@ -10,6 +10,10 @@
     {
       "type": "alpha-value",
       "syntax": "<number> | <percentage>"
+    },
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/hypot.json b/testing/data/function__hypot.json
similarity index 100%
rename from testing/data/hypot.json
rename to testing/data/function__hypot.json
diff --git a/testing/data/image__image-set.json b/testing/data/function__image-set.json
similarity index 86%
rename from testing/data/image__image-set.json
rename to testing/data/function__image-set.json
index 8e4767a..6a6ec4b 100644
--- a/testing/data/image__image-set.json
+++ b/testing/data/function__image-set.json
@@ -11,6 +11,10 @@
       "type": "image",
       "syntax": "<url> | <gradient>"
     },
+    {
+      "type": "resolution",
+      "syntax": "<dpi> | <dpcm> | <dppx> | <x>"
+    },
     {
       "type": "url",
       "syntax": "<url()> | <src()>"
diff --git a/testing/data/image__image.json b/testing/data/function__image.json
similarity index 100%
rename from testing/data/image__image.json
rename to testing/data/function__image.json
diff --git a/testing/data/filter-function__invert.json b/testing/data/function__invert.json
similarity index 100%
rename from testing/data/filter-function__invert.json
rename to testing/data/function__invert.json
diff --git a/testing/data/color_value__lab.json b/testing/data/function__lab.json
similarity index 100%
rename from testing/data/color_value__lab.json
rename to testing/data/function__lab.json
diff --git a/testing/data/color_value__lch.json b/testing/data/function__lch.json
similarity index 80%
rename from testing/data/color_value__lch.json
rename to testing/data/function__lch.json
index 9314b2d..4adcc63 100644
--- a/testing/data/color_value__lch.json
+++ b/testing/data/function__lch.json
@@ -10,6 +10,10 @@
     {
       "type": "alpha-value",
       "syntax": "<number> | <percentage>"
+    },
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/gradient__linear-gradient.json b/testing/data/function__linear-gradient.json
similarity index 89%
rename from testing/data/gradient__linear-gradient.json
rename to testing/data/function__linear-gradient.json
index a47e2e6..d734b3a 100644
--- a/testing/data/gradient__linear-gradient.json
+++ b/testing/data/function__linear-gradient.json
@@ -7,6 +7,10 @@
       "type": "linear-gradient-syntax",
       "syntax": "[ <angle> | to <side-or-corner> ]? , <color-stop-list>"
     },
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    },
     {
       "type": "side-or-corner",
       "syntax": "[left | right] || [top | bottom]"
diff --git a/testing/data/log.json b/testing/data/function__log.json
similarity index 100%
rename from testing/data/log.json
rename to testing/data/function__log.json
diff --git a/testing/data/transform-function__matrix.json b/testing/data/function__matrix.json
similarity index 100%
rename from testing/data/transform-function__matrix.json
rename to testing/data/function__matrix.json
diff --git a/testing/data/transform-function__matrix3d.json b/testing/data/function__matrix3d.json
similarity index 100%
rename from testing/data/transform-function__matrix3d.json
rename to testing/data/function__matrix3d.json
diff --git a/testing/data/max.json b/testing/data/function__max.json
similarity index 100%
rename from testing/data/max.json
rename to testing/data/function__max.json
diff --git a/testing/data/min.json b/testing/data/function__min.json
similarity index 100%
rename from testing/data/min.json
rename to testing/data/function__min.json
diff --git a/testing/data/minmax.json b/testing/data/function__minmax.json
similarity index 100%
rename from testing/data/minmax.json
rename to testing/data/function__minmax.json
diff --git a/testing/data/mod.json b/testing/data/function__mod.json
similarity index 100%
rename from testing/data/mod.json
rename to testing/data/function__mod.json
diff --git a/testing/data/color_value__oklab.json b/testing/data/function__oklab.json
similarity index 100%
rename from testing/data/color_value__oklab.json
rename to testing/data/function__oklab.json
diff --git a/testing/data/color_value__oklch.json b/testing/data/function__oklch.json
similarity index 80%
rename from testing/data/color_value__oklch.json
rename to testing/data/function__oklch.json
index 02b8b01..7083f29 100644
--- a/testing/data/color_value__oklch.json
+++ b/testing/data/function__oklch.json
@@ -10,6 +10,10 @@
     {
       "type": "alpha-value",
       "syntax": "<number> | <percentage>"
+    },
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/filter-function__opacity.json b/testing/data/function__opacity.json
similarity index 100%
rename from testing/data/filter-function__opacity.json
rename to testing/data/function__opacity.json
diff --git a/testing/data/image__paint.json b/testing/data/function__paint.json
similarity index 100%
rename from testing/data/image__paint.json
rename to testing/data/function__paint.json
diff --git a/testing/data/transform-function__perspective.json b/testing/data/function__perspective.json
similarity index 100%
rename from testing/data/transform-function__perspective.json
rename to testing/data/function__perspective.json
diff --git a/testing/data/pow.json b/testing/data/function__pow.json
similarity index 100%
rename from testing/data/pow.json
rename to testing/data/function__pow.json
diff --git a/testing/data/gradient__radial-gradient.json b/testing/data/function__radial-gradient.json
similarity index 100%
rename from testing/data/gradient__radial-gradient.json
rename to testing/data/function__radial-gradient.json
diff --git a/testing/data/ray.json b/testing/data/function__ray.json
similarity index 88%
rename from testing/data/ray.json
rename to testing/data/function__ray.json
index 1aeca5e..4fff343 100644
--- a/testing/data/ray.json
+++ b/testing/data/function__ray.json
@@ -3,6 +3,10 @@
   "type": "function",
   "syntax": "ray( <angle> && <ray-size>? && contain? && [at <position>]? )",
   "constituents": [
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    },
     {
       "type": "ray-size",
       "syntax": "closest-side | closest-corner | farthest-side | farthest-corner | sides"
diff --git a/testing/data/function__rect.json b/testing/data/function__rect.json
new file mode 100644
index 0000000..31dd5d9
--- /dev/null
+++ b/testing/data/function__rect.json
@@ -0,0 +1,23 @@
+{
+  "name": "rect",
+  "type": "function",
+  "syntax": "rect( <top>, <right>, <bottom>, <left> )",
+  "constituents": [
+    {
+      "type": "top",
+      "syntax": "<auto>"
+    },
+    {
+      "type": "right",
+      "syntax": "<auto>"
+    },
+    {
+      "type": "bottom",
+      "syntax": "<auto>"
+    },
+    {
+      "type": "left",
+      "syntax": "<auto>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/rem.json b/testing/data/function__rem.json
similarity index 100%
rename from testing/data/rem.json
rename to testing/data/function__rem.json
diff --git a/testing/data/gradient__repeating-conic-gradient.json b/testing/data/function__repeating-conic-gradient.json
similarity index 95%
rename from testing/data/gradient__repeating-conic-gradient.json
rename to testing/data/function__repeating-conic-gradient.json
index d1dba79..1a13d27 100644
--- a/testing/data/gradient__repeating-conic-gradient.json
+++ b/testing/data/function__repeating-conic-gradient.json
@@ -7,6 +7,10 @@
       "type": "conic-gradient-syntax",
       "syntax": "[ [ [ from <angle> ]? [ at <position> ]? ] || <color-interpolation-method> ]? , <angular-color-stop-list>"
     },
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    },
     {
       "type": "position",
       "syntax": "[ [ left | center | right ] || [ top | center | bottom ] | [ left | center | right | <length-percentage> ] [ top | center | bottom | <length-percentage> ]? | [ [ left | right ] <length-percentage> ] && [ [ top | bottom ] <length-percentage> ] ]"
diff --git a/testing/data/gradient__repeating-linear-gradient.json b/testing/data/function__repeating-linear-gradient.json
similarity index 90%
rename from testing/data/gradient__repeating-linear-gradient.json
rename to testing/data/function__repeating-linear-gradient.json
index 842f793..d130429 100644
--- a/testing/data/gradient__repeating-linear-gradient.json
+++ b/testing/data/function__repeating-linear-gradient.json
@@ -7,6 +7,10 @@
       "type": "linear-gradient-syntax",
       "syntax": "[ <angle> | to <side-or-corner> ]? , <color-stop-list>"
     },
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    },
     {
       "type": "side-or-corner",
       "syntax": "[left | right] || [top | bottom]"
diff --git a/testing/data/gradient__repeating-radial-gradient.json b/testing/data/function__repeating-radial-gradient.json
similarity index 100%
rename from testing/data/gradient__repeating-radial-gradient.json
rename to testing/data/function__repeating-radial-gradient.json
diff --git a/testing/data/color_value__rgb.json b/testing/data/function__rgb.json
similarity index 100%
rename from testing/data/color_value__rgb.json
rename to testing/data/function__rgb.json
diff --git a/testing/data/function__rotate.json b/testing/data/function__rotate.json
new file mode 100644
index 0000000..f7c96bc
--- /dev/null
+++ b/testing/data/function__rotate.json
@@ -0,0 +1,11 @@
+{
+  "name": "rotate",
+  "type": "function",
+  "syntax": "rotate( [ <angle> | <zero> ] )",
+  "constituents": [
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/transform-function__rotate3d.json b/testing/data/function__rotate3d.json
similarity index 54%
rename from testing/data/transform-function__rotate3d.json
rename to testing/data/function__rotate3d.json
index afe1059..8629927 100644
--- a/testing/data/transform-function__rotate3d.json
+++ b/testing/data/function__rotate3d.json
@@ -2,5 +2,10 @@
   "name": "rotate3d",
   "type": "function",
   "syntax": "rotate3d( <number> , <number> , <number> , [ <angle> | <zero> ] )",
-  "constituents": []
+  "constituents": [
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    }
+  ]
 }
\ No newline at end of file
diff --git a/testing/data/round.json b/testing/data/function__round.json
similarity index 100%
rename from testing/data/round.json
rename to testing/data/function__round.json
diff --git a/testing/data/filter-function__saturate.json b/testing/data/function__saturate.json
similarity index 100%
rename from testing/data/filter-function__saturate.json
rename to testing/data/function__saturate.json
diff --git a/testing/data/transform-function__scale.json b/testing/data/function__scale.json
similarity index 100%
rename from testing/data/transform-function__scale.json
rename to testing/data/function__scale.json
diff --git a/testing/data/transform-function__scale3d.json b/testing/data/function__scale3d.json
similarity index 100%
rename from testing/data/transform-function__scale3d.json
rename to testing/data/function__scale3d.json
diff --git a/testing/data/animation-timeline__scroll.json b/testing/data/function__scroll.json
similarity index 100%
rename from testing/data/animation-timeline__scroll.json
rename to testing/data/function__scroll.json
diff --git a/testing/data/filter-function__sepia.json b/testing/data/function__sepia.json
similarity index 100%
rename from testing/data/filter-function__sepia.json
rename to testing/data/function__sepia.json
diff --git a/testing/data/sign.json b/testing/data/function__sign.json
similarity index 100%
rename from testing/data/sign.json
rename to testing/data/function__sign.json
diff --git a/testing/data/sin.json b/testing/data/function__sin.json
similarity index 100%
rename from testing/data/sin.json
rename to testing/data/function__sin.json
diff --git a/testing/data/transform-function__skew.json b/testing/data/function__skew.json
similarity index 50%
rename from testing/data/transform-function__skew.json
rename to testing/data/function__skew.json
index e7492df..1696cf0 100644
--- a/testing/data/transform-function__skew.json
+++ b/testing/data/function__skew.json
@@ -2,5 +2,10 @@
   "name": "skew",
   "type": "function",
   "syntax": "skew( [ <angle> | <zero> ] , [ <angle> | <zero> ]? )",
-  "constituents": []
+  "constituents": [
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    }
+  ]
 }
\ No newline at end of file
diff --git a/testing/data/sqrt.json b/testing/data/function__sqrt.json
similarity index 100%
rename from testing/data/sqrt.json
rename to testing/data/function__sqrt.json
diff --git a/testing/data/symbols.json b/testing/data/function__symbols.json
similarity index 100%
rename from testing/data/symbols.json
rename to testing/data/function__symbols.json
diff --git a/testing/data/tan.json b/testing/data/function__tan.json
similarity index 100%
rename from testing/data/tan.json
rename to testing/data/function__tan.json
diff --git a/testing/data/transform-function__translate.json b/testing/data/function__translate.json
similarity index 100%
rename from testing/data/transform-function__translate.json
rename to testing/data/function__translate.json
diff --git a/testing/data/transform-function__translate3d.json b/testing/data/function__translate3d.json
similarity index 100%
rename from testing/data/transform-function__translate3d.json
rename to testing/data/function__translate3d.json
diff --git a/testing/data/url.json b/testing/data/function__url.json
similarity index 100%
rename from testing/data/url.json
rename to testing/data/function__url.json
diff --git a/testing/data/var.json b/testing/data/function__var.json
similarity index 100%
rename from testing/data/var.json
rename to testing/data/function__var.json
diff --git a/testing/data/animation-timeline__view.json b/testing/data/function__view.json
similarity index 100%
rename from testing/data/animation-timeline__view.json
rename to testing/data/function__view.json
diff --git a/testing/data/hue.json b/testing/data/hue.json
deleted file mode 100644
index 357d35f..0000000
--- a/testing/data/hue.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "hue",
-  "type": "type",
-  "syntax": "<number> | <angle>",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/image-resolution.json b/testing/data/image-resolution.json
deleted file mode 100644
index 441114c..0000000
--- a/testing/data/image-resolution.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "image-resolution",
-  "type": "property",
-  "syntax": "[ from-image || <resolution> ] && snap?",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/inset-block.json b/testing/data/inset-block.json
deleted file mode 100644
index 35f4995..0000000
--- a/testing/data/inset-block.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "inset-block",
-  "type": "property",
-  "syntax": "<top>{1,2}",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/inset-inline.json b/testing/data/inset-inline.json
deleted file mode 100644
index 5f298c2..0000000
--- a/testing/data/inset-inline.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "inset-inline",
-  "type": "property",
-  "syntax": "<top>{1,2}",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/inset.json b/testing/data/inset.json
deleted file mode 100644
index f6bb868..0000000
--- a/testing/data/inset.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "inset",
-  "type": "property",
-  "syntax": "<top>{1,4}",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/list-style-type.json b/testing/data/list-style-type.json
deleted file mode 100644
index 43afbae..0000000
--- a/testing/data/list-style-type.json
+++ /dev/null
@@ -1,35 +0,0 @@
-{
-  "name": "list-style-type",
-  "type": "property",
-  "syntax": "<counter-style> | <string> | none",
-  "constituents": [
-    {
-      "type": "counter-style",
-      "syntax": "<counter-style-name> | <symbols()>"
-    },
-    {
-      "type": "symbols()",
-      "syntax": "symbols( <symbols-type>? [ <string> | <image> ]+ )"
-    },
-    {
-      "type": "symbols-type",
-      "syntax": "cyclic | numeric | alphabetic | symbolic | fixed"
-    },
-    {
-      "type": "image",
-      "syntax": "<url> | <gradient>"
-    },
-    {
-      "type": "url",
-      "syntax": "<url()> | <src()>"
-    },
-    {
-      "type": "url()",
-      "syntax": "url( <string> <url-modifier>* ) | <url-token>"
-    },
-    {
-      "type": "src()",
-      "syntax": "src( <string> <url-modifier>* )"
-    }
-  ]
-}
\ No newline at end of file
diff --git a/testing/data/offset-rotate.json b/testing/data/offset-rotate.json
deleted file mode 100644
index 17ba547..0000000
--- a/testing/data/offset-rotate.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "offset-rotate",
-  "type": "property",
-  "syntax": "[ auto | reverse ] || <angle>",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/-webkit-line-clamp.json b/testing/data/property__-webkit-line-clamp.json
similarity index 100%
rename from testing/data/-webkit-line-clamp.json
rename to testing/data/property__-webkit-line-clamp.json
diff --git a/testing/data/-webkit-text-fill-color.json b/testing/data/property__-webkit-text-fill-color.json
similarity index 100%
rename from testing/data/-webkit-text-fill-color.json
rename to testing/data/property__-webkit-text-fill-color.json
diff --git a/testing/data/-webkit-text-stroke-color.json b/testing/data/property__-webkit-text-stroke-color.json
similarity index 100%
rename from testing/data/-webkit-text-stroke-color.json
rename to testing/data/property__-webkit-text-stroke-color.json
diff --git a/testing/data/-webkit-text-stroke-width.json b/testing/data/property__-webkit-text-stroke-width.json
similarity index 100%
rename from testing/data/-webkit-text-stroke-width.json
rename to testing/data/property__-webkit-text-stroke-width.json
diff --git a/testing/data/-webkit-text-stroke.json b/testing/data/property__-webkit-text-stroke.json
similarity index 100%
rename from testing/data/-webkit-text-stroke.json
rename to testing/data/property__-webkit-text-stroke.json
diff --git a/testing/data/accent-color.json b/testing/data/property__accent-color.json
similarity index 100%
rename from testing/data/accent-color.json
rename to testing/data/property__accent-color.json
diff --git a/testing/data/align-content.json b/testing/data/property__align-content.json
similarity index 100%
rename from testing/data/align-content.json
rename to testing/data/property__align-content.json
diff --git a/testing/data/align-items.json b/testing/data/property__align-items.json
similarity index 90%
rename from testing/data/align-items.json
rename to testing/data/property__align-items.json
index 920abed..2aba405 100644
--- a/testing/data/align-items.json
+++ b/testing/data/property__align-items.json
@@ -1,7 +1,7 @@
 {
   "name": "align-items",
   "type": "property",
-  "syntax": "normal | stretch | <baseline-position> | [ <overflow-position>? <self-position> ]",
+  "syntax": "normal | stretch | <baseline-position> | [ <overflow-position>? <self-position> ] | anchor-center",
   "constituents": [
     {
       "type": "baseline-position",
diff --git a/testing/data/align-self.json b/testing/data/property__align-self.json
similarity index 89%
rename from testing/data/align-self.json
rename to testing/data/property__align-self.json
index c7124e5..248aafb 100644
--- a/testing/data/align-self.json
+++ b/testing/data/property__align-self.json
@@ -1,7 +1,7 @@
 {
   "name": "align-self",
   "type": "property",
-  "syntax": "auto | normal | stretch | <baseline-position> | <overflow-position>? <self-position>",
+  "syntax": "auto | normal | stretch | <baseline-position> | <overflow-position>? <self-position> | anchor-center",
   "constituents": [
     {
       "type": "baseline-position",
diff --git a/testing/data/align-tracks.json b/testing/data/property__align-tracks.json
similarity index 100%
rename from testing/data/align-tracks.json
rename to testing/data/property__align-tracks.json
diff --git a/testing/data/all.json b/testing/data/property__all.json
similarity index 100%
rename from testing/data/all.json
rename to testing/data/property__all.json
diff --git a/testing/data/animation-composition.json b/testing/data/property__animation-composition.json
similarity index 100%
rename from testing/data/animation-composition.json
rename to testing/data/property__animation-composition.json
diff --git a/testing/data/property__animation-delay.json b/testing/data/property__animation-delay.json
new file mode 100644
index 0000000..6b218cc
--- /dev/null
+++ b/testing/data/property__animation-delay.json
@@ -0,0 +1,11 @@
+{
+  "name": "animation-delay",
+  "type": "property",
+  "syntax": "<time>#",
+  "constituents": [
+    {
+      "type": "time",
+      "syntax": "<s> | <ms>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/animation-direction.json b/testing/data/property__animation-direction.json
similarity index 100%
rename from testing/data/animation-direction.json
rename to testing/data/property__animation-direction.json
diff --git a/testing/data/animation-duration.json b/testing/data/property__animation-duration.json
similarity index 50%
rename from testing/data/animation-duration.json
rename to testing/data/property__animation-duration.json
index 8975098..995bd10 100644
--- a/testing/data/animation-duration.json
+++ b/testing/data/property__animation-duration.json
@@ -2,5 +2,10 @@
   "name": "animation-duration",
   "type": "property",
   "syntax": "<time [0s,∞]>#",
-  "constituents": []
+  "constituents": [
+    {
+      "type": "time",
+      "syntax": "<s> | <ms>"
+    }
+  ]
 }
\ No newline at end of file
diff --git a/testing/data/animation-fill-mode.json b/testing/data/property__animation-fill-mode.json
similarity index 100%
rename from testing/data/animation-fill-mode.json
rename to testing/data/property__animation-fill-mode.json
diff --git a/testing/data/animation-iteration-count.json b/testing/data/property__animation-iteration-count.json
similarity index 100%
rename from testing/data/animation-iteration-count.json
rename to testing/data/property__animation-iteration-count.json
diff --git a/testing/data/animation-name.json b/testing/data/property__animation-name.json
similarity index 100%
rename from testing/data/animation-name.json
rename to testing/data/property__animation-name.json
diff --git a/testing/data/animation-play-state.json b/testing/data/property__animation-play-state.json
similarity index 100%
rename from testing/data/animation-play-state.json
rename to testing/data/property__animation-play-state.json
diff --git a/testing/data/animation-range-end.json b/testing/data/property__animation-range-end.json
similarity index 100%
rename from testing/data/animation-range-end.json
rename to testing/data/property__animation-range-end.json
diff --git a/testing/data/animation-range-start.json b/testing/data/property__animation-range-start.json
similarity index 100%
rename from testing/data/animation-range-start.json
rename to testing/data/property__animation-range-start.json
diff --git a/testing/data/animation-range.json b/testing/data/property__animation-range.json
similarity index 100%
rename from testing/data/animation-range.json
rename to testing/data/property__animation-range.json
diff --git a/testing/data/animation-timeline.json b/testing/data/property__animation-timeline.json
similarity index 100%
rename from testing/data/animation-timeline.json
rename to testing/data/property__animation-timeline.json
diff --git a/testing/data/animation-timing-function.json b/testing/data/property__animation-timing-function.json
similarity index 100%
rename from testing/data/animation-timing-function.json
rename to testing/data/property__animation-timing-function.json
diff --git a/testing/data/animation.json b/testing/data/property__animation.json
similarity index 96%
rename from testing/data/animation.json
rename to testing/data/property__animation.json
index bbf0eb5..1e8bb34 100644
--- a/testing/data/animation.json
+++ b/testing/data/property__animation.json
@@ -7,6 +7,10 @@
       "type": "single-animation",
       "syntax": "<time [0s,∞]> || <easing-function> || <time> || <single-animation-iteration-count> || <single-animation-direction> || <single-animation-fill-mode> || <single-animation-play-state> || [ none | <keyframes-name> ]"
     },
+    {
+      "type": "time",
+      "syntax": "<s> | <ms>"
+    },
     {
       "type": "easing-function",
       "syntax": "linear | <linear-easing-function> | <cubic-bezier-easing-function> | <step-easing-function>"
diff --git a/testing/data/appearance.json b/testing/data/property__appearance.json
similarity index 100%
rename from testing/data/appearance.json
rename to testing/data/property__appearance.json
diff --git a/testing/data/aspect-ratio.json b/testing/data/property__aspect-ratio.json
similarity index 100%
rename from testing/data/aspect-ratio.json
rename to testing/data/property__aspect-ratio.json
diff --git a/testing/data/backdrop-filter.json b/testing/data/property__backdrop-filter.json
similarity index 95%
rename from testing/data/backdrop-filter.json
rename to testing/data/property__backdrop-filter.json
index 9d642b4..5ce74dc 100644
--- a/testing/data/backdrop-filter.json
+++ b/testing/data/property__backdrop-filter.json
@@ -62,6 +62,10 @@
     {
       "type": "src()",
       "syntax": "src( <string> <url-modifier>* )"
+    },
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/backface-visibility.json b/testing/data/property__backface-visibility.json
similarity index 100%
rename from testing/data/backface-visibility.json
rename to testing/data/property__backface-visibility.json
diff --git a/testing/data/background-attachment.json b/testing/data/property__background-attachment.json
similarity index 100%
rename from testing/data/background-attachment.json
rename to testing/data/property__background-attachment.json
diff --git a/testing/data/background-blend-mode.json b/testing/data/property__background-blend-mode.json
similarity index 100%
rename from testing/data/background-blend-mode.json
rename to testing/data/property__background-blend-mode.json
diff --git a/testing/data/background-clip.json b/testing/data/property__background-clip.json
similarity index 100%
rename from testing/data/background-clip.json
rename to testing/data/property__background-clip.json
diff --git a/testing/data/background-color.json b/testing/data/property__background-color.json
similarity index 100%
rename from testing/data/background-color.json
rename to testing/data/property__background-color.json
diff --git a/testing/data/background-image.json b/testing/data/property__background-image.json
similarity index 100%
rename from testing/data/background-image.json
rename to testing/data/property__background-image.json
diff --git a/testing/data/background-origin.json b/testing/data/property__background-origin.json
similarity index 100%
rename from testing/data/background-origin.json
rename to testing/data/property__background-origin.json
diff --git a/testing/data/background-position-x.json b/testing/data/property__background-position-x.json
similarity index 100%
rename from testing/data/background-position-x.json
rename to testing/data/property__background-position-x.json
diff --git a/testing/data/background-position-y.json b/testing/data/property__background-position-y.json
similarity index 100%
rename from testing/data/background-position-y.json
rename to testing/data/property__background-position-y.json
diff --git a/testing/data/background-position.json b/testing/data/property__background-position.json
similarity index 100%
rename from testing/data/background-position.json
rename to testing/data/property__background-position.json
diff --git a/testing/data/background-repeat.json b/testing/data/property__background-repeat.json
similarity index 100%
rename from testing/data/background-repeat.json
rename to testing/data/property__background-repeat.json
diff --git a/testing/data/background-size.json b/testing/data/property__background-size.json
similarity index 100%
rename from testing/data/background-size.json
rename to testing/data/property__background-size.json
diff --git a/testing/data/background.json b/testing/data/property__background.json
similarity index 100%
rename from testing/data/background.json
rename to testing/data/property__background.json
diff --git a/testing/data/block-size.json b/testing/data/property__block-size.json
similarity index 54%
rename from testing/data/block-size.json
rename to testing/data/property__block-size.json
index 0451d56..f3f7051 100644
--- a/testing/data/block-size.json
+++ b/testing/data/property__block-size.json
@@ -1,6 +1,6 @@
 {
   "name": "block-size",
   "type": "property",
-  "syntax": "<'width'>",
+  "syntax": "<'width'> | stretch | fit-content | contain",
   "constituents": []
 }
\ No newline at end of file
diff --git a/testing/data/border-block-color.json b/testing/data/property__border-block-color.json
similarity index 100%
rename from testing/data/border-block-color.json
rename to testing/data/property__border-block-color.json
diff --git a/testing/data/border-block-end-color.json b/testing/data/property__border-block-end-color.json
similarity index 100%
rename from testing/data/border-block-end-color.json
rename to testing/data/property__border-block-end-color.json
diff --git a/testing/data/border-block-end-style.json b/testing/data/property__border-block-end-style.json
similarity index 100%
rename from testing/data/border-block-end-style.json
rename to testing/data/property__border-block-end-style.json
diff --git a/testing/data/border-block-end-width.json b/testing/data/property__border-block-end-width.json
similarity index 100%
rename from testing/data/border-block-end-width.json
rename to testing/data/property__border-block-end-width.json
diff --git a/testing/data/border-block-end.json b/testing/data/property__border-block-end.json
similarity index 100%
rename from testing/data/border-block-end.json
rename to testing/data/property__border-block-end.json
diff --git a/testing/data/border-block-start-color.json b/testing/data/property__border-block-start-color.json
similarity index 100%
rename from testing/data/border-block-start-color.json
rename to testing/data/property__border-block-start-color.json
diff --git a/testing/data/border-block-start-style.json b/testing/data/property__border-block-start-style.json
similarity index 100%
rename from testing/data/border-block-start-style.json
rename to testing/data/property__border-block-start-style.json
diff --git a/testing/data/border-block-start-width.json b/testing/data/property__border-block-start-width.json
similarity index 100%
rename from testing/data/border-block-start-width.json
rename to testing/data/property__border-block-start-width.json
diff --git a/testing/data/border-block-start.json b/testing/data/property__border-block-start.json
similarity index 100%
rename from testing/data/border-block-start.json
rename to testing/data/property__border-block-start.json
diff --git a/testing/data/border-block-style.json b/testing/data/property__border-block-style.json
similarity index 100%
rename from testing/data/border-block-style.json
rename to testing/data/property__border-block-style.json
diff --git a/testing/data/border-block-width.json b/testing/data/property__border-block-width.json
similarity index 100%
rename from testing/data/border-block-width.json
rename to testing/data/property__border-block-width.json
diff --git a/testing/data/border-block.json b/testing/data/property__border-block.json
similarity index 100%
rename from testing/data/border-block.json
rename to testing/data/property__border-block.json
diff --git a/testing/data/border-bottom-color.json b/testing/data/property__border-bottom-color.json
similarity index 89%
rename from testing/data/border-bottom-color.json
rename to testing/data/property__border-bottom-color.json
index ff439ab..1140a5e 100644
--- a/testing/data/border-bottom-color.json
+++ b/testing/data/property__border-bottom-color.json
@@ -18,6 +18,10 @@
     {
       "type": "length-percentage",
       "syntax": "[ <length> | <percentage> ]"
+    },
+    {
+      "type": "flex",
+      "syntax": "<fr>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/border-bottom-left-radius.json b/testing/data/property__border-bottom-left-radius.json
similarity index 100%
rename from testing/data/border-bottom-left-radius.json
rename to testing/data/property__border-bottom-left-radius.json
diff --git a/testing/data/border-bottom-right-radius.json b/testing/data/property__border-bottom-right-radius.json
similarity index 100%
rename from testing/data/border-bottom-right-radius.json
rename to testing/data/property__border-bottom-right-radius.json
diff --git a/testing/data/border-bottom-style.json b/testing/data/property__border-bottom-style.json
similarity index 100%
rename from testing/data/border-bottom-style.json
rename to testing/data/property__border-bottom-style.json
diff --git a/testing/data/border-bottom-width.json b/testing/data/property__border-bottom-width.json
similarity index 100%
rename from testing/data/border-bottom-width.json
rename to testing/data/property__border-bottom-width.json
diff --git a/testing/data/border-bottom.json b/testing/data/property__border-bottom.json
similarity index 100%
rename from testing/data/border-bottom.json
rename to testing/data/property__border-bottom.json
diff --git a/testing/data/border-collapse.json b/testing/data/property__border-collapse.json
similarity index 100%
rename from testing/data/border-collapse.json
rename to testing/data/property__border-collapse.json
diff --git a/testing/data/border-color.json b/testing/data/property__border-color.json
similarity index 89%
rename from testing/data/border-color.json
rename to testing/data/property__border-color.json
index 542c4dd..ecff9fb 100644
--- a/testing/data/border-color.json
+++ b/testing/data/property__border-color.json
@@ -18,6 +18,10 @@
     {
       "type": "length-percentage",
       "syntax": "[ <length> | <percentage> ]"
+    },
+    {
+      "type": "flex",
+      "syntax": "<fr>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/border-end-end-radius.json b/testing/data/property__border-end-end-radius.json
similarity index 100%
rename from testing/data/border-end-end-radius.json
rename to testing/data/property__border-end-end-radius.json
diff --git a/testing/data/border-end-start-radius.json b/testing/data/property__border-end-start-radius.json
similarity index 100%
rename from testing/data/border-end-start-radius.json
rename to testing/data/property__border-end-start-radius.json
diff --git a/testing/data/border-image-outset.json b/testing/data/property__border-image-outset.json
similarity index 100%
rename from testing/data/border-image-outset.json
rename to testing/data/property__border-image-outset.json
diff --git a/testing/data/border-image-repeat.json b/testing/data/property__border-image-repeat.json
similarity index 100%
rename from testing/data/border-image-repeat.json
rename to testing/data/property__border-image-repeat.json
diff --git a/testing/data/border-image-slice.json b/testing/data/property__border-image-slice.json
similarity index 100%
rename from testing/data/border-image-slice.json
rename to testing/data/property__border-image-slice.json
diff --git a/testing/data/border-image-source.json b/testing/data/property__border-image-source.json
similarity index 100%
rename from testing/data/border-image-source.json
rename to testing/data/property__border-image-source.json
diff --git a/testing/data/border-image-width.json b/testing/data/property__border-image-width.json
similarity index 100%
rename from testing/data/border-image-width.json
rename to testing/data/property__border-image-width.json
diff --git a/testing/data/border-image.json b/testing/data/property__border-image.json
similarity index 100%
rename from testing/data/border-image.json
rename to testing/data/property__border-image.json
diff --git a/testing/data/border-inline-color.json b/testing/data/property__border-inline-color.json
similarity index 100%
rename from testing/data/border-inline-color.json
rename to testing/data/property__border-inline-color.json
diff --git a/testing/data/border-inline-end-color.json b/testing/data/property__border-inline-end-color.json
similarity index 100%
rename from testing/data/border-inline-end-color.json
rename to testing/data/property__border-inline-end-color.json
diff --git a/testing/data/border-inline-end-style.json b/testing/data/property__border-inline-end-style.json
similarity index 100%
rename from testing/data/border-inline-end-style.json
rename to testing/data/property__border-inline-end-style.json
diff --git a/testing/data/border-inline-end-width.json b/testing/data/property__border-inline-end-width.json
similarity index 100%
rename from testing/data/border-inline-end-width.json
rename to testing/data/property__border-inline-end-width.json
diff --git a/testing/data/border-inline-end.json b/testing/data/property__border-inline-end.json
similarity index 100%
rename from testing/data/border-inline-end.json
rename to testing/data/property__border-inline-end.json
diff --git a/testing/data/border-inline-start-color.json b/testing/data/property__border-inline-start-color.json
similarity index 100%
rename from testing/data/border-inline-start-color.json
rename to testing/data/property__border-inline-start-color.json
diff --git a/testing/data/border-inline-start-style.json b/testing/data/property__border-inline-start-style.json
similarity index 100%
rename from testing/data/border-inline-start-style.json
rename to testing/data/property__border-inline-start-style.json
diff --git a/testing/data/border-inline-start-width.json b/testing/data/property__border-inline-start-width.json
similarity index 100%
rename from testing/data/border-inline-start-width.json
rename to testing/data/property__border-inline-start-width.json
diff --git a/testing/data/border-inline-start.json b/testing/data/property__border-inline-start.json
similarity index 100%
rename from testing/data/border-inline-start.json
rename to testing/data/property__border-inline-start.json
diff --git a/testing/data/border-inline-style.json b/testing/data/property__border-inline-style.json
similarity index 100%
rename from testing/data/border-inline-style.json
rename to testing/data/property__border-inline-style.json
diff --git a/testing/data/border-inline-width.json b/testing/data/property__border-inline-width.json
similarity index 100%
rename from testing/data/border-inline-width.json
rename to testing/data/property__border-inline-width.json
diff --git a/testing/data/border-inline.json b/testing/data/property__border-inline.json
similarity index 100%
rename from testing/data/border-inline.json
rename to testing/data/property__border-inline.json
diff --git a/testing/data/border-left-color.json b/testing/data/property__border-left-color.json
similarity index 88%
rename from testing/data/border-left-color.json
rename to testing/data/property__border-left-color.json
index 083b07f..afcf497 100644
--- a/testing/data/border-left-color.json
+++ b/testing/data/property__border-left-color.json
@@ -18,6 +18,10 @@
     {
       "type": "length-percentage",
       "syntax": "[ <length> | <percentage> ]"
+    },
+    {
+      "type": "flex",
+      "syntax": "<fr>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/border-left-style.json b/testing/data/property__border-left-style.json
similarity index 100%
rename from testing/data/border-left-style.json
rename to testing/data/property__border-left-style.json
diff --git a/testing/data/border-left-width.json b/testing/data/property__border-left-width.json
similarity index 100%
rename from testing/data/border-left-width.json
rename to testing/data/property__border-left-width.json
diff --git a/testing/data/border-left.json b/testing/data/property__border-left.json
similarity index 100%
rename from testing/data/border-left.json
rename to testing/data/property__border-left.json
diff --git a/testing/data/border-radius.json b/testing/data/property__border-radius.json
similarity index 100%
rename from testing/data/border-radius.json
rename to testing/data/property__border-radius.json
diff --git a/testing/data/border-right-color.json b/testing/data/property__border-right-color.json
similarity index 89%
rename from testing/data/border-right-color.json
rename to testing/data/property__border-right-color.json
index 3e75fc1..00af8e9 100644
--- a/testing/data/border-right-color.json
+++ b/testing/data/property__border-right-color.json
@@ -18,6 +18,10 @@
     {
       "type": "length-percentage",
       "syntax": "[ <length> | <percentage> ]"
+    },
+    {
+      "type": "flex",
+      "syntax": "<fr>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/border-right-style.json b/testing/data/property__border-right-style.json
similarity index 100%
rename from testing/data/border-right-style.json
rename to testing/data/property__border-right-style.json
diff --git a/testing/data/border-right-width.json b/testing/data/property__border-right-width.json
similarity index 100%
rename from testing/data/border-right-width.json
rename to testing/data/property__border-right-width.json
diff --git a/testing/data/border-right.json b/testing/data/property__border-right.json
similarity index 100%
rename from testing/data/border-right.json
rename to testing/data/property__border-right.json
diff --git a/testing/data/border-spacing.json b/testing/data/property__border-spacing.json
similarity index 100%
rename from testing/data/border-spacing.json
rename to testing/data/property__border-spacing.json
diff --git a/testing/data/border-start-end-radius.json b/testing/data/property__border-start-end-radius.json
similarity index 100%
rename from testing/data/border-start-end-radius.json
rename to testing/data/property__border-start-end-radius.json
diff --git a/testing/data/border-start-start-radius.json b/testing/data/property__border-start-start-radius.json
similarity index 100%
rename from testing/data/border-start-start-radius.json
rename to testing/data/property__border-start-start-radius.json
diff --git a/testing/data/border-style.json b/testing/data/property__border-style.json
similarity index 100%
rename from testing/data/border-style.json
rename to testing/data/property__border-style.json
diff --git a/testing/data/border-top-color.json b/testing/data/property__border-top-color.json
similarity index 88%
rename from testing/data/border-top-color.json
rename to testing/data/property__border-top-color.json
index 4b46d9c..bf151e0 100644
--- a/testing/data/border-top-color.json
+++ b/testing/data/property__border-top-color.json
@@ -18,6 +18,10 @@
     {
       "type": "length-percentage",
       "syntax": "[ <length> | <percentage> ]"
+    },
+    {
+      "type": "flex",
+      "syntax": "<fr>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/border-top-left-radius.json b/testing/data/property__border-top-left-radius.json
similarity index 100%
rename from testing/data/border-top-left-radius.json
rename to testing/data/property__border-top-left-radius.json
diff --git a/testing/data/border-top-right-radius.json b/testing/data/property__border-top-right-radius.json
similarity index 100%
rename from testing/data/border-top-right-radius.json
rename to testing/data/property__border-top-right-radius.json
diff --git a/testing/data/border-top-style.json b/testing/data/property__border-top-style.json
similarity index 100%
rename from testing/data/border-top-style.json
rename to testing/data/property__border-top-style.json
diff --git a/testing/data/border-top-width.json b/testing/data/property__border-top-width.json
similarity index 100%
rename from testing/data/border-top-width.json
rename to testing/data/property__border-top-width.json
diff --git a/testing/data/border-top.json b/testing/data/property__border-top.json
similarity index 100%
rename from testing/data/border-top.json
rename to testing/data/property__border-top.json
diff --git a/testing/data/border-width.json b/testing/data/property__border-width.json
similarity index 100%
rename from testing/data/border-width.json
rename to testing/data/property__border-width.json
diff --git a/testing/data/border.json b/testing/data/property__border.json
similarity index 100%
rename from testing/data/border.json
rename to testing/data/property__border.json
diff --git a/testing/data/bottom.json b/testing/data/property__bottom.json
similarity index 100%
rename from testing/data/bottom.json
rename to testing/data/property__bottom.json
diff --git a/testing/data/box-decoration-break.json b/testing/data/property__box-decoration-break.json
similarity index 100%
rename from testing/data/box-decoration-break.json
rename to testing/data/property__box-decoration-break.json
diff --git a/testing/data/box-shadow.json b/testing/data/property__box-shadow.json
similarity index 100%
rename from testing/data/box-shadow.json
rename to testing/data/property__box-shadow.json
diff --git a/testing/data/box-sizing.json b/testing/data/property__box-sizing.json
similarity index 100%
rename from testing/data/box-sizing.json
rename to testing/data/property__box-sizing.json
diff --git a/testing/data/break-after.json b/testing/data/property__break-after.json
similarity index 100%
rename from testing/data/break-after.json
rename to testing/data/property__break-after.json
diff --git a/testing/data/break-before.json b/testing/data/property__break-before.json
similarity index 100%
rename from testing/data/break-before.json
rename to testing/data/property__break-before.json
diff --git a/testing/data/break-inside.json b/testing/data/property__break-inside.json
similarity index 100%
rename from testing/data/break-inside.json
rename to testing/data/property__break-inside.json
diff --git a/testing/data/caption-side.json b/testing/data/property__caption-side.json
similarity index 100%
rename from testing/data/caption-side.json
rename to testing/data/property__caption-side.json
diff --git a/testing/data/caret-color.json b/testing/data/property__caret-color.json
similarity index 100%
rename from testing/data/caret-color.json
rename to testing/data/property__caret-color.json
diff --git a/testing/data/clear.json b/testing/data/property__clear.json
similarity index 100%
rename from testing/data/clear.json
rename to testing/data/property__clear.json
diff --git a/testing/data/clip-path.json b/testing/data/property__clip-path.json
similarity index 52%
rename from testing/data/clip-path.json
rename to testing/data/property__clip-path.json
index 3b52a53..7ad096c 100644
--- a/testing/data/clip-path.json
+++ b/testing/data/property__clip-path.json
@@ -7,6 +7,10 @@
       "type": "clip-source",
       "syntax": "<url>"
     },
+    {
+      "type": "basic-shape",
+      "syntax": "<inset()> | <xywh()> | <rect()> | <circle()> | <ellipse()> | <polygon()> | <path()>"
+    },
     {
       "type": "geometry-box",
       "syntax": "<shape-box> | fill-box | stroke-box | view-box"
@@ -15,6 +19,18 @@
       "type": "url",
       "syntax": "<url()> | <src()>"
     },
+    {
+      "type": "length-percentage",
+      "syntax": "[ <length> | <percentage> ]"
+    },
+    {
+      "type": "shape-radius",
+      "syntax": "<length-percentage [0,∞]> | closest-side | farthest-side"
+    },
+    {
+      "type": "position",
+      "syntax": "[ [ left | center | right ] || [ top | center | bottom ] | [ left | center | right | <length-percentage> ] [ top | center | bottom | <length-percentage> ]? | [ [ left | right ] <length-percentage> ] && [ [ top | bottom ] <length-percentage> ] ]"
+    },
     {
       "type": "shape-box",
       "syntax": "<box> | margin-box"
diff --git a/testing/data/property__clip.json b/testing/data/property__clip.json
new file mode 100644
index 0000000..6587298
--- /dev/null
+++ b/testing/data/property__clip.json
@@ -0,0 +1,27 @@
+{
+  "name": "clip",
+  "type": "property",
+  "syntax": "<rect()> | auto",
+  "constituents": [
+    {
+      "type": "rect()",
+      "syntax": "rect( <top>, <right>, <bottom>, <left> )"
+    },
+    {
+      "type": "top",
+      "syntax": "<auto>"
+    },
+    {
+      "type": "right",
+      "syntax": "<auto>"
+    },
+    {
+      "type": "bottom",
+      "syntax": "<auto>"
+    },
+    {
+      "type": "left",
+      "syntax": "<auto>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/color-scheme.json b/testing/data/property__color-scheme.json
similarity index 100%
rename from testing/data/color-scheme.json
rename to testing/data/property__color-scheme.json
diff --git a/testing/data/color.json b/testing/data/property__color.json
similarity index 100%
rename from testing/data/color.json
rename to testing/data/property__color.json
diff --git a/testing/data/column-count.json b/testing/data/property__column-count.json
similarity index 100%
rename from testing/data/column-count.json
rename to testing/data/property__column-count.json
diff --git a/testing/data/column-fill.json b/testing/data/property__column-fill.json
similarity index 100%
rename from testing/data/column-fill.json
rename to testing/data/property__column-fill.json
diff --git a/testing/data/column-gap.json b/testing/data/property__column-gap.json
similarity index 100%
rename from testing/data/column-gap.json
rename to testing/data/property__column-gap.json
diff --git a/testing/data/column-rule-color.json b/testing/data/property__column-rule-color.json
similarity index 100%
rename from testing/data/column-rule-color.json
rename to testing/data/property__column-rule-color.json
diff --git a/testing/data/column-rule-style.json b/testing/data/property__column-rule-style.json
similarity index 100%
rename from testing/data/column-rule-style.json
rename to testing/data/property__column-rule-style.json
diff --git a/testing/data/column-rule-width.json b/testing/data/property__column-rule-width.json
similarity index 100%
rename from testing/data/column-rule-width.json
rename to testing/data/property__column-rule-width.json
diff --git a/testing/data/column-rule.json b/testing/data/property__column-rule.json
similarity index 100%
rename from testing/data/column-rule.json
rename to testing/data/property__column-rule.json
diff --git a/testing/data/column-span.json b/testing/data/property__column-span.json
similarity index 100%
rename from testing/data/column-span.json
rename to testing/data/property__column-span.json
diff --git a/testing/data/property__column-width.json b/testing/data/property__column-width.json
new file mode 100644
index 0000000..32f2771
--- /dev/null
+++ b/testing/data/property__column-width.json
@@ -0,0 +1,11 @@
+{
+  "name": "column-width",
+  "type": "property",
+  "syntax": "auto | <length [0,∞]> | min-content | max-content | fit-content(<length-percentage>)",
+  "constituents": [
+    {
+      "type": "length-percentage",
+      "syntax": "[ <length> | <percentage> ]"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/columns.json b/testing/data/property__columns.json
similarity index 100%
rename from testing/data/columns.json
rename to testing/data/property__columns.json
diff --git a/testing/data/contain-intrinsic-block-size.json b/testing/data/property__contain-intrinsic-block-size.json
similarity index 100%
rename from testing/data/contain-intrinsic-block-size.json
rename to testing/data/property__contain-intrinsic-block-size.json
diff --git a/testing/data/contain-intrinsic-height.json b/testing/data/property__contain-intrinsic-height.json
similarity index 100%
rename from testing/data/contain-intrinsic-height.json
rename to testing/data/property__contain-intrinsic-height.json
diff --git a/testing/data/contain-intrinsic-inline-size.json b/testing/data/property__contain-intrinsic-inline-size.json
similarity index 100%
rename from testing/data/contain-intrinsic-inline-size.json
rename to testing/data/property__contain-intrinsic-inline-size.json
diff --git a/testing/data/contain-intrinsic-size.json b/testing/data/property__contain-intrinsic-size.json
similarity index 100%
rename from testing/data/contain-intrinsic-size.json
rename to testing/data/property__contain-intrinsic-size.json
diff --git a/testing/data/contain-intrinsic-width.json b/testing/data/property__contain-intrinsic-width.json
similarity index 100%
rename from testing/data/contain-intrinsic-width.json
rename to testing/data/property__contain-intrinsic-width.json
diff --git a/testing/data/contain.json b/testing/data/property__contain.json
similarity index 100%
rename from testing/data/contain.json
rename to testing/data/property__contain.json
diff --git a/testing/data/container-name.json b/testing/data/property__container-name.json
similarity index 100%
rename from testing/data/container-name.json
rename to testing/data/property__container-name.json
diff --git a/testing/data/container-type.json b/testing/data/property__container-type.json
similarity index 100%
rename from testing/data/container-type.json
rename to testing/data/property__container-type.json
diff --git a/testing/data/container.json b/testing/data/property__container.json
similarity index 100%
rename from testing/data/container.json
rename to testing/data/property__container.json
diff --git a/testing/data/content-visibility.json b/testing/data/property__content-visibility.json
similarity index 100%
rename from testing/data/content-visibility.json
rename to testing/data/property__content-visibility.json
diff --git a/testing/data/content.json b/testing/data/property__content.json
similarity index 71%
rename from testing/data/content.json
rename to testing/data/property__content.json
index 0a32ce8..c3f454d 100644
--- a/testing/data/content.json
+++ b/testing/data/property__content.json
@@ -1,7 +1,7 @@
 {
   "name": "content",
   "type": "property",
-  "syntax": "normal | none | [ <content-replacement> | <content-list> ] [/ [ <string> | <counter> ]+ ]?",
+  "syntax": "normal | none | [ <content-replacement> | <content-list> ] [/ [ <string> | <counter> ]+ ]? | element()",
   "constituents": [
     {
       "type": "content-replacement",
@@ -71,6 +71,10 @@
       "type": "src()",
       "syntax": "src( <string> <url-modifier>* )"
     },
+    {
+      "type": "counter-style-name",
+      "syntax": "<decimal> | <decimal-leading-zero> | <arabic-indic> | <armenian> | <upper-armenian> | <lower-armenian> | <bengali> | <cambodian> | <khmer> | <cjk-decimal> | <devanagari> | <georgian> | <gujarati> | <gurmukhi> | <hebrew> | <kannada> | <lao> | <malayalam> | <mongolian> | <myanmar> | <oriya> | <persian> | <lower-roman> | <upper-roman> | <tamil> | <telugu> | <thai> | <tibetan> | <lower-alpha> | <lower-latin> | <upper-alpha> | <upper-latin> | <lower-greek> | <hiragana> | <hiragana-iroha> | <katakana> | <katakana-iroha> | <disc> | <circle> | <square> | <disclosure-open> | <disclosure-closed> | <cjk-earthly-branch> | <cjk-heavenly-stem> | <korean-hangul-formal> | <korean-hanja-informal> | <korean-hanja-formal> | <ethiopic-numeric>"
+    },
     {
       "type": "symbols()",
       "syntax": "symbols( <symbols-type>? [ <string> | <image> ]+ )"
diff --git a/testing/data/counter-increment.json b/testing/data/property__counter-increment.json
similarity index 100%
rename from testing/data/counter-increment.json
rename to testing/data/property__counter-increment.json
diff --git a/testing/data/counter-reset.json b/testing/data/property__counter-reset.json
similarity index 100%
rename from testing/data/counter-reset.json
rename to testing/data/property__counter-reset.json
diff --git a/testing/data/counter-set.json b/testing/data/property__counter-set.json
similarity index 100%
rename from testing/data/counter-set.json
rename to testing/data/property__counter-set.json
diff --git a/testing/data/cursor.json b/testing/data/property__cursor.json
similarity index 100%
rename from testing/data/cursor.json
rename to testing/data/property__cursor.json
diff --git a/testing/data/direction.json b/testing/data/property__direction.json
similarity index 100%
rename from testing/data/direction.json
rename to testing/data/property__direction.json
diff --git a/testing/data/display.json b/testing/data/property__display.json
similarity index 94%
rename from testing/data/display.json
rename to testing/data/property__display.json
index 5821bbc..3587eb5 100644
--- a/testing/data/display.json
+++ b/testing/data/property__display.json
@@ -1,7 +1,7 @@
 {
   "name": "display",
   "type": "property",
-  "syntax": "[ <display-outside> || <display-inside> ] | <display-listitem> | <display-internal> | <display-box> | <display-legacy>",
+  "syntax": "[ <display-outside> || <display-inside> ] | <display-listitem> | <display-internal> | <display-box> | <display-legacy> | <display-outside> || [ <display-inside> | math ]",
   "constituents": [
     {
       "type": "display-outside",
diff --git a/testing/data/empty-cells.json b/testing/data/property__empty-cells.json
similarity index 100%
rename from testing/data/empty-cells.json
rename to testing/data/property__empty-cells.json
diff --git a/testing/data/filter.json b/testing/data/property__filter.json
similarity index 95%
rename from testing/data/filter.json
rename to testing/data/property__filter.json
index 19408d5..2926462 100644
--- a/testing/data/filter.json
+++ b/testing/data/property__filter.json
@@ -62,6 +62,10 @@
     {
       "type": "src()",
       "syntax": "src( <string> <url-modifier>* )"
+    },
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/flex-basis.json b/testing/data/property__flex-basis.json
similarity index 100%
rename from testing/data/flex-basis.json
rename to testing/data/property__flex-basis.json
diff --git a/testing/data/flex-direction.json b/testing/data/property__flex-direction.json
similarity index 100%
rename from testing/data/flex-direction.json
rename to testing/data/property__flex-direction.json
diff --git a/testing/data/flex-flow.json b/testing/data/property__flex-flow.json
similarity index 100%
rename from testing/data/flex-flow.json
rename to testing/data/property__flex-flow.json
diff --git a/testing/data/flex-grow.json b/testing/data/property__flex-grow.json
similarity index 100%
rename from testing/data/flex-grow.json
rename to testing/data/property__flex-grow.json
diff --git a/testing/data/flex-shrink.json b/testing/data/property__flex-shrink.json
similarity index 100%
rename from testing/data/flex-shrink.json
rename to testing/data/property__flex-shrink.json
diff --git a/testing/data/flex-wrap.json b/testing/data/property__flex-wrap.json
similarity index 100%
rename from testing/data/flex-wrap.json
rename to testing/data/property__flex-wrap.json
diff --git a/testing/data/flex.json b/testing/data/property__flex.json
similarity index 100%
rename from testing/data/flex.json
rename to testing/data/property__flex.json
diff --git a/testing/data/float.json b/testing/data/property__float.json
similarity index 100%
rename from testing/data/float.json
rename to testing/data/property__float.json
diff --git a/testing/data/property__font-family.json b/testing/data/property__font-family.json
new file mode 100644
index 0000000..8560213
--- /dev/null
+++ b/testing/data/property__font-family.json
@@ -0,0 +1,11 @@
+{
+  "name": "font-family",
+  "type": "property",
+  "syntax": "[ <family-name> | <generic-family> ]#",
+  "constituents": [
+    {
+      "type": "generic-family",
+      "syntax": "<serif> | <sans-serif> | <cursive> | <fantasy> | <monospace> | <system-ui> | <emoji> | <math> | <fangsong> | <ui-serif> | <ui-sans-serif> | <ui-monospace> | <ui-rounded>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/font-feature-settings.json b/testing/data/property__font-feature-settings.json
similarity index 100%
rename from testing/data/font-feature-settings.json
rename to testing/data/property__font-feature-settings.json
diff --git a/testing/data/font-kerning.json b/testing/data/property__font-kerning.json
similarity index 100%
rename from testing/data/font-kerning.json
rename to testing/data/property__font-kerning.json
diff --git a/testing/data/font-language-override.json b/testing/data/property__font-language-override.json
similarity index 100%
rename from testing/data/font-language-override.json
rename to testing/data/property__font-language-override.json
diff --git a/testing/data/font-optical-sizing.json b/testing/data/property__font-optical-sizing.json
similarity index 100%
rename from testing/data/font-optical-sizing.json
rename to testing/data/property__font-optical-sizing.json
diff --git a/testing/data/font-palette.json b/testing/data/property__font-palette.json
similarity index 100%
rename from testing/data/font-palette.json
rename to testing/data/property__font-palette.json
diff --git a/testing/data/font-size-adjust.json b/testing/data/property__font-size-adjust.json
similarity index 100%
rename from testing/data/font-size-adjust.json
rename to testing/data/property__font-size-adjust.json
diff --git a/testing/data/font-size.json b/testing/data/property__font-size.json
similarity index 100%
rename from testing/data/font-size.json
rename to testing/data/property__font-size.json
diff --git a/testing/data/font-stretch.json b/testing/data/property__font-stretch.json
similarity index 100%
rename from testing/data/font-stretch.json
rename to testing/data/property__font-stretch.json
diff --git a/testing/data/font-style.json b/testing/data/property__font-style.json
similarity index 51%
rename from testing/data/font-style.json
rename to testing/data/property__font-style.json
index f5ec159..d58b044 100644
--- a/testing/data/font-style.json
+++ b/testing/data/property__font-style.json
@@ -2,5 +2,10 @@
   "name": "font-style",
   "type": "property",
   "syntax": "normal | italic | oblique <angle [-90deg,90deg]>?",
-  "constituents": []
+  "constituents": [
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    }
+  ]
 }
\ No newline at end of file
diff --git a/testing/data/font-synthesis-position.json b/testing/data/property__font-synthesis-position.json
similarity index 100%
rename from testing/data/font-synthesis-position.json
rename to testing/data/property__font-synthesis-position.json
diff --git a/testing/data/font-synthesis-small-caps.json b/testing/data/property__font-synthesis-small-caps.json
similarity index 100%
rename from testing/data/font-synthesis-small-caps.json
rename to testing/data/property__font-synthesis-small-caps.json
diff --git a/testing/data/font-synthesis-style.json b/testing/data/property__font-synthesis-style.json
similarity index 100%
rename from testing/data/font-synthesis-style.json
rename to testing/data/property__font-synthesis-style.json
diff --git a/testing/data/font-synthesis-weight.json b/testing/data/property__font-synthesis-weight.json
similarity index 100%
rename from testing/data/font-synthesis-weight.json
rename to testing/data/property__font-synthesis-weight.json
diff --git a/testing/data/font-synthesis.json b/testing/data/property__font-synthesis.json
similarity index 100%
rename from testing/data/font-synthesis.json
rename to testing/data/property__font-synthesis.json
diff --git a/testing/data/font-variant-alternates.json b/testing/data/property__font-variant-alternates.json
similarity index 100%
rename from testing/data/font-variant-alternates.json
rename to testing/data/property__font-variant-alternates.json
diff --git a/testing/data/font-variant-caps.json b/testing/data/property__font-variant-caps.json
similarity index 100%
rename from testing/data/font-variant-caps.json
rename to testing/data/property__font-variant-caps.json
diff --git a/testing/data/font-variant-east-asian.json b/testing/data/property__font-variant-east-asian.json
similarity index 100%
rename from testing/data/font-variant-east-asian.json
rename to testing/data/property__font-variant-east-asian.json
diff --git a/testing/data/font-variant-emoji.json b/testing/data/property__font-variant-emoji.json
similarity index 100%
rename from testing/data/font-variant-emoji.json
rename to testing/data/property__font-variant-emoji.json
diff --git a/testing/data/font-variant-ligatures.json b/testing/data/property__font-variant-ligatures.json
similarity index 100%
rename from testing/data/font-variant-ligatures.json
rename to testing/data/property__font-variant-ligatures.json
diff --git a/testing/data/font-variant-numeric.json b/testing/data/property__font-variant-numeric.json
similarity index 100%
rename from testing/data/font-variant-numeric.json
rename to testing/data/property__font-variant-numeric.json
diff --git a/testing/data/font-variant-position.json b/testing/data/property__font-variant-position.json
similarity index 100%
rename from testing/data/font-variant-position.json
rename to testing/data/property__font-variant-position.json
diff --git a/testing/data/font-variant.json b/testing/data/property__font-variant.json
similarity index 100%
rename from testing/data/font-variant.json
rename to testing/data/property__font-variant.json
diff --git a/testing/data/font-variation-settings.json b/testing/data/property__font-variation-settings.json
similarity index 100%
rename from testing/data/font-variation-settings.json
rename to testing/data/property__font-variation-settings.json
diff --git a/testing/data/font-weight.json b/testing/data/property__font-weight.json
similarity index 100%
rename from testing/data/font-weight.json
rename to testing/data/property__font-weight.json
diff --git a/testing/data/font.json b/testing/data/property__font.json
similarity index 100%
rename from testing/data/font.json
rename to testing/data/property__font.json
diff --git a/testing/data/forced-color-adjust.json b/testing/data/property__forced-color-adjust.json
similarity index 100%
rename from testing/data/forced-color-adjust.json
rename to testing/data/property__forced-color-adjust.json
diff --git a/testing/data/gap.json b/testing/data/property__gap.json
similarity index 100%
rename from testing/data/gap.json
rename to testing/data/property__gap.json
diff --git a/testing/data/grid-area.json b/testing/data/property__grid-area.json
similarity index 100%
rename from testing/data/grid-area.json
rename to testing/data/property__grid-area.json
diff --git a/testing/data/grid-auto-columns.json b/testing/data/property__grid-auto-columns.json
similarity index 91%
rename from testing/data/grid-auto-columns.json
rename to testing/data/property__grid-auto-columns.json
index a78eebb..b16d390 100644
--- a/testing/data/grid-auto-columns.json
+++ b/testing/data/property__grid-auto-columns.json
@@ -18,6 +18,10 @@
     {
       "type": "length-percentage",
       "syntax": "[ <length> | <percentage> ]"
+    },
+    {
+      "type": "flex",
+      "syntax": "<fr>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/grid-auto-flow.json b/testing/data/property__grid-auto-flow.json
similarity index 100%
rename from testing/data/grid-auto-flow.json
rename to testing/data/property__grid-auto-flow.json
diff --git a/testing/data/grid-auto-rows.json b/testing/data/property__grid-auto-rows.json
similarity index 91%
rename from testing/data/grid-auto-rows.json
rename to testing/data/property__grid-auto-rows.json
index 62db452..208def7 100644
--- a/testing/data/grid-auto-rows.json
+++ b/testing/data/property__grid-auto-rows.json
@@ -18,6 +18,10 @@
     {
       "type": "length-percentage",
       "syntax": "[ <length> | <percentage> ]"
+    },
+    {
+      "type": "flex",
+      "syntax": "<fr>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/grid-column-end.json b/testing/data/property__grid-column-end.json
similarity index 100%
rename from testing/data/grid-column-end.json
rename to testing/data/property__grid-column-end.json
diff --git a/testing/data/grid-column-start.json b/testing/data/property__grid-column-start.json
similarity index 100%
rename from testing/data/grid-column-start.json
rename to testing/data/property__grid-column-start.json
diff --git a/testing/data/grid-column.json b/testing/data/property__grid-column.json
similarity index 100%
rename from testing/data/grid-column.json
rename to testing/data/property__grid-column.json
diff --git a/testing/data/grid-row-end.json b/testing/data/property__grid-row-end.json
similarity index 100%
rename from testing/data/grid-row-end.json
rename to testing/data/property__grid-row-end.json
diff --git a/testing/data/grid-row-start.json b/testing/data/property__grid-row-start.json
similarity index 100%
rename from testing/data/grid-row-start.json
rename to testing/data/property__grid-row-start.json
diff --git a/testing/data/grid-row.json b/testing/data/property__grid-row.json
similarity index 100%
rename from testing/data/grid-row.json
rename to testing/data/property__grid-row.json
diff --git a/testing/data/grid-template-areas.json b/testing/data/property__grid-template-areas.json
similarity index 100%
rename from testing/data/grid-template-areas.json
rename to testing/data/property__grid-template-areas.json
diff --git a/testing/data/grid-template-columns.json b/testing/data/property__grid-template-columns.json
similarity index 95%
rename from testing/data/grid-template-columns.json
rename to testing/data/property__grid-template-columns.json
index 3bca28f..1c4c033 100644
--- a/testing/data/grid-template-columns.json
+++ b/testing/data/property__grid-template-columns.json
@@ -1,7 +1,7 @@
 {
   "name": "grid-template-columns",
   "type": "property",
-  "syntax": "none | <track-list> | <auto-track-list> | subgrid <line-name-list>?",
+  "syntax": "none | <track-list> | <auto-track-list> | subgrid <line-name-list>? | masonry",
   "constituents": [
     {
       "type": "track-list",
@@ -58,6 +58,10 @@
     {
       "type": "fixed-breadth",
       "syntax": "<length-percentage [0,∞]>"
+    },
+    {
+      "type": "flex",
+      "syntax": "<fr>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/grid-template-rows.json b/testing/data/property__grid-template-rows.json
similarity index 95%
rename from testing/data/grid-template-rows.json
rename to testing/data/property__grid-template-rows.json
index c528993..e3f3df5 100644
--- a/testing/data/grid-template-rows.json
+++ b/testing/data/property__grid-template-rows.json
@@ -1,7 +1,7 @@
 {
   "name": "grid-template-rows",
   "type": "property",
-  "syntax": "none | <track-list> | <auto-track-list> | subgrid <line-name-list>?",
+  "syntax": "none | <track-list> | <auto-track-list> | subgrid <line-name-list>? | masonry",
   "constituents": [
     {
       "type": "track-list",
@@ -58,6 +58,10 @@
     {
       "type": "fixed-breadth",
       "syntax": "<length-percentage [0,∞]>"
+    },
+    {
+      "type": "flex",
+      "syntax": "<fr>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/grid-template.json b/testing/data/property__grid-template.json
similarity index 94%
rename from testing/data/grid-template.json
rename to testing/data/property__grid-template.json
index e023f8f..60d6033 100644
--- a/testing/data/grid-template.json
+++ b/testing/data/property__grid-template.json
@@ -26,6 +26,10 @@
     {
       "type": "length-percentage",
       "syntax": "[ <length> | <percentage> ]"
+    },
+    {
+      "type": "flex",
+      "syntax": "<fr>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/grid.json b/testing/data/property__grid.json
similarity index 100%
rename from testing/data/grid.json
rename to testing/data/property__grid.json
diff --git a/testing/data/hanging-punctuation.json b/testing/data/property__hanging-punctuation.json
similarity index 100%
rename from testing/data/hanging-punctuation.json
rename to testing/data/property__hanging-punctuation.json
diff --git a/testing/data/height.json b/testing/data/property__height.json
similarity index 71%
rename from testing/data/height.json
rename to testing/data/property__height.json
index 31f6d2a..f12bb60 100644
--- a/testing/data/height.json
+++ b/testing/data/property__height.json
@@ -1,7 +1,7 @@
 {
   "name": "height",
   "type": "property",
-  "syntax": "auto | <length-percentage [0,∞]> | min-content | max-content | fit-content(<length-percentage [0,∞]>)",
+  "syntax": "auto | <length-percentage [0,∞]> | min-content | max-content | fit-content(<length-percentage [0,∞]>) | stretch | fit-content | contain",
   "constituents": [
     {
       "type": "length-percentage",
diff --git a/testing/data/hyphenate-character.json b/testing/data/property__hyphenate-character.json
similarity index 100%
rename from testing/data/hyphenate-character.json
rename to testing/data/property__hyphenate-character.json
diff --git a/testing/data/hyphenate-limit-chars.json b/testing/data/property__hyphenate-limit-chars.json
similarity index 100%
rename from testing/data/hyphenate-limit-chars.json
rename to testing/data/property__hyphenate-limit-chars.json
diff --git a/testing/data/hyphens.json b/testing/data/property__hyphens.json
similarity index 100%
rename from testing/data/hyphens.json
rename to testing/data/property__hyphens.json
diff --git a/testing/data/image-orientation.json b/testing/data/property__image-orientation.json
similarity index 50%
rename from testing/data/image-orientation.json
rename to testing/data/property__image-orientation.json
index a36dc5b..2cfca4b 100644
--- a/testing/data/image-orientation.json
+++ b/testing/data/property__image-orientation.json
@@ -2,5 +2,10 @@
   "name": "image-orientation",
   "type": "property",
   "syntax": "from-image | none | [ <angle> || flip ]",
-  "constituents": []
+  "constituents": [
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    }
+  ]
 }
\ No newline at end of file
diff --git a/testing/data/image-rendering.json b/testing/data/property__image-rendering.json
similarity index 100%
rename from testing/data/image-rendering.json
rename to testing/data/property__image-rendering.json
diff --git a/testing/data/property__image-resolution.json b/testing/data/property__image-resolution.json
new file mode 100644
index 0000000..3b0e79e
--- /dev/null
+++ b/testing/data/property__image-resolution.json
@@ -0,0 +1,11 @@
+{
+  "name": "image-resolution",
+  "type": "property",
+  "syntax": "[ from-image || <resolution> ] && snap?",
+  "constituents": [
+    {
+      "type": "resolution",
+      "syntax": "<dpi> | <dpcm> | <dppx> | <x>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/initial-letter-align.json b/testing/data/property__initial-letter-align.json
similarity index 100%
rename from testing/data/initial-letter-align.json
rename to testing/data/property__initial-letter-align.json
diff --git a/testing/data/initial-letter.json b/testing/data/property__initial-letter.json
similarity index 100%
rename from testing/data/initial-letter.json
rename to testing/data/property__initial-letter.json
diff --git a/testing/data/inline-size.json b/testing/data/property__inline-size.json
similarity index 54%
rename from testing/data/inline-size.json
rename to testing/data/property__inline-size.json
index 35e7881..60a08f6 100644
--- a/testing/data/inline-size.json
+++ b/testing/data/property__inline-size.json
@@ -1,6 +1,6 @@
 {
   "name": "inline-size",
   "type": "property",
-  "syntax": "<'width'>",
+  "syntax": "<'width'> | stretch | fit-content | contain",
   "constituents": []
 }
\ No newline at end of file
diff --git a/testing/data/inset-block-end.json b/testing/data/property__inset-block-end.json
similarity index 100%
rename from testing/data/inset-block-end.json
rename to testing/data/property__inset-block-end.json
diff --git a/testing/data/inset-block-start.json b/testing/data/property__inset-block-start.json
similarity index 100%
rename from testing/data/inset-block-start.json
rename to testing/data/property__inset-block-start.json
diff --git a/testing/data/property__inset-block.json b/testing/data/property__inset-block.json
new file mode 100644
index 0000000..a55c5fa
--- /dev/null
+++ b/testing/data/property__inset-block.json
@@ -0,0 +1,11 @@
+{
+  "name": "inset-block",
+  "type": "property",
+  "syntax": "<top>{1,2}",
+  "constituents": [
+    {
+      "type": "top",
+      "syntax": "<auto>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/inset-inline-end.json b/testing/data/property__inset-inline-end.json
similarity index 100%
rename from testing/data/inset-inline-end.json
rename to testing/data/property__inset-inline-end.json
diff --git a/testing/data/inset-inline-start.json b/testing/data/property__inset-inline-start.json
similarity index 100%
rename from testing/data/inset-inline-start.json
rename to testing/data/property__inset-inline-start.json
diff --git a/testing/data/property__inset-inline.json b/testing/data/property__inset-inline.json
new file mode 100644
index 0000000..7deab48
--- /dev/null
+++ b/testing/data/property__inset-inline.json
@@ -0,0 +1,11 @@
+{
+  "name": "inset-inline",
+  "type": "property",
+  "syntax": "<top>{1,2}",
+  "constituents": [
+    {
+      "type": "top",
+      "syntax": "<auto>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/property__inset.json b/testing/data/property__inset.json
new file mode 100644
index 0000000..87e8073
--- /dev/null
+++ b/testing/data/property__inset.json
@@ -0,0 +1,11 @@
+{
+  "name": "inset",
+  "type": "property",
+  "syntax": "<top>{1,4}",
+  "constituents": [
+    {
+      "type": "top",
+      "syntax": "<auto>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/isolation.json b/testing/data/property__isolation.json
similarity index 100%
rename from testing/data/isolation.json
rename to testing/data/property__isolation.json
diff --git a/testing/data/justify-content.json b/testing/data/property__justify-content.json
similarity index 100%
rename from testing/data/justify-content.json
rename to testing/data/property__justify-content.json
diff --git a/testing/data/justify-items.json b/testing/data/property__justify-items.json
similarity index 91%
rename from testing/data/justify-items.json
rename to testing/data/property__justify-items.json
index a444362..83d1c8a 100644
--- a/testing/data/justify-items.json
+++ b/testing/data/property__justify-items.json
@@ -1,7 +1,7 @@
 {
   "name": "justify-items",
   "type": "property",
-  "syntax": "normal | stretch | <baseline-position> | <overflow-position>? [ <self-position> | left | right ] | legacy | legacy && [ left | right | center ]",
+  "syntax": "normal | stretch | <baseline-position> | <overflow-position>? [ <self-position> | left | right ] | legacy | legacy && [ left | right | center ] | anchor-center",
   "constituents": [
     {
       "type": "baseline-position",
diff --git a/testing/data/justify-self.json b/testing/data/property__justify-self.json
similarity index 86%
rename from testing/data/justify-self.json
rename to testing/data/property__justify-self.json
index 8887656..f9acdeb 100644
--- a/testing/data/justify-self.json
+++ b/testing/data/property__justify-self.json
@@ -1,7 +1,7 @@
 {
   "name": "justify-self",
   "type": "property",
-  "syntax": "auto | normal | stretch | <baseline-position> | <overflow-position>? [ <self-position> | left | right ]",
+  "syntax": "auto | normal | stretch | <baseline-position> | <overflow-position>? [ <self-position> | left | right ] | anchor-center",
   "constituents": [
     {
       "type": "baseline-position",
diff --git a/testing/data/justify-tracks.json b/testing/data/property__justify-tracks.json
similarity index 100%
rename from testing/data/justify-tracks.json
rename to testing/data/property__justify-tracks.json
diff --git a/testing/data/left.json b/testing/data/property__left.json
similarity index 100%
rename from testing/data/left.json
rename to testing/data/property__left.json
diff --git a/testing/data/letter-spacing.json b/testing/data/property__letter-spacing.json
similarity index 100%
rename from testing/data/letter-spacing.json
rename to testing/data/property__letter-spacing.json
diff --git a/testing/data/line-break.json b/testing/data/property__line-break.json
similarity index 100%
rename from testing/data/line-break.json
rename to testing/data/property__line-break.json
diff --git a/testing/data/line-height-step.json b/testing/data/property__line-height-step.json
similarity index 100%
rename from testing/data/line-height-step.json
rename to testing/data/property__line-height-step.json
diff --git a/testing/data/line-height.json b/testing/data/property__line-height.json
similarity index 100%
rename from testing/data/line-height.json
rename to testing/data/property__line-height.json
diff --git a/testing/data/list-style-image.json b/testing/data/property__list-style-image.json
similarity index 100%
rename from testing/data/list-style-image.json
rename to testing/data/property__list-style-image.json
diff --git a/testing/data/list-style-position.json b/testing/data/property__list-style-position.json
similarity index 100%
rename from testing/data/list-style-position.json
rename to testing/data/property__list-style-position.json
diff --git a/testing/data/property__list-style-type.json b/testing/data/property__list-style-type.json
new file mode 100644
index 0000000..7aed719
--- /dev/null
+++ b/testing/data/property__list-style-type.json
@@ -0,0 +1,39 @@
+{
+  "name": "list-style-type",
+  "type": "property",
+  "syntax": "<counter-style> | <string> | none",
+  "constituents": [
+    {
+      "type": "counter-style",
+      "syntax": "<counter-style-name> | <symbols()>"
+    },
+    {
+      "type": "counter-style-name",
+      "syntax": "<decimal> | <decimal-leading-zero> | <arabic-indic> | <armenian> | <upper-armenian> | <lower-armenian> | <bengali> | <cambodian> | <khmer> | <cjk-decimal> | <devanagari> | <georgian> | <gujarati> | <gurmukhi> | <hebrew> | <kannada> | <lao> | <malayalam> | <mongolian> | <myanmar> | <oriya> | <persian> | <lower-roman> | <upper-roman> | <tamil> | <telugu> | <thai> | <tibetan> | <lower-alpha> | <lower-latin> | <upper-alpha> | <upper-latin> | <lower-greek> | <hiragana> | <hiragana-iroha> | <katakana> | <katakana-iroha> | <disc> | <circle> | <square> | <disclosure-open> | <disclosure-closed> | <cjk-earthly-branch> | <cjk-heavenly-stem> | <korean-hangul-formal> | <korean-hanja-informal> | <korean-hanja-formal> | <ethiopic-numeric>"
+    },
+    {
+      "type": "symbols()",
+      "syntax": "symbols( <symbols-type>? [ <string> | <image> ]+ )"
+    },
+    {
+      "type": "symbols-type",
+      "syntax": "cyclic | numeric | alphabetic | symbolic | fixed"
+    },
+    {
+      "type": "image",
+      "syntax": "<url> | <gradient>"
+    },
+    {
+      "type": "url",
+      "syntax": "<url()> | <src()>"
+    },
+    {
+      "type": "url()",
+      "syntax": "url( <string> <url-modifier>* ) | <url-token>"
+    },
+    {
+      "type": "src()",
+      "syntax": "src( <string> <url-modifier>* )"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/list-style.json b/testing/data/property__list-style.json
similarity index 100%
rename from testing/data/list-style.json
rename to testing/data/property__list-style.json
diff --git a/testing/data/margin-block-end.json b/testing/data/property__margin-block-end.json
similarity index 100%
rename from testing/data/margin-block-end.json
rename to testing/data/property__margin-block-end.json
diff --git a/testing/data/margin-block-start.json b/testing/data/property__margin-block-start.json
similarity index 100%
rename from testing/data/margin-block-start.json
rename to testing/data/property__margin-block-start.json
diff --git a/testing/data/margin-block.json b/testing/data/property__margin-block.json
similarity index 100%
rename from testing/data/margin-block.json
rename to testing/data/property__margin-block.json
diff --git a/testing/data/margin-bottom.json b/testing/data/property__margin-bottom.json
similarity index 100%
rename from testing/data/margin-bottom.json
rename to testing/data/property__margin-bottom.json
diff --git a/testing/data/margin-inline-end.json b/testing/data/property__margin-inline-end.json
similarity index 100%
rename from testing/data/margin-inline-end.json
rename to testing/data/property__margin-inline-end.json
diff --git a/testing/data/margin-inline-start.json b/testing/data/property__margin-inline-start.json
similarity index 100%
rename from testing/data/margin-inline-start.json
rename to testing/data/property__margin-inline-start.json
diff --git a/testing/data/margin-inline.json b/testing/data/property__margin-inline.json
similarity index 100%
rename from testing/data/margin-inline.json
rename to testing/data/property__margin-inline.json
diff --git a/testing/data/margin-left.json b/testing/data/property__margin-left.json
similarity index 100%
rename from testing/data/margin-left.json
rename to testing/data/property__margin-left.json
diff --git a/testing/data/margin-right.json b/testing/data/property__margin-right.json
similarity index 100%
rename from testing/data/margin-right.json
rename to testing/data/property__margin-right.json
diff --git a/testing/data/margin-top.json b/testing/data/property__margin-top.json
similarity index 100%
rename from testing/data/margin-top.json
rename to testing/data/property__margin-top.json
diff --git a/testing/data/margin-trim.json b/testing/data/property__margin-trim.json
similarity index 100%
rename from testing/data/margin-trim.json
rename to testing/data/property__margin-trim.json
diff --git a/testing/data/margin.json b/testing/data/property__margin.json
similarity index 100%
rename from testing/data/margin.json
rename to testing/data/property__margin.json
diff --git a/testing/data/mask-border-mode.json b/testing/data/property__mask-border-mode.json
similarity index 100%
rename from testing/data/mask-border-mode.json
rename to testing/data/property__mask-border-mode.json
diff --git a/testing/data/mask-border-outset.json b/testing/data/property__mask-border-outset.json
similarity index 100%
rename from testing/data/mask-border-outset.json
rename to testing/data/property__mask-border-outset.json
diff --git a/testing/data/mask-border-repeat.json b/testing/data/property__mask-border-repeat.json
similarity index 100%
rename from testing/data/mask-border-repeat.json
rename to testing/data/property__mask-border-repeat.json
diff --git a/testing/data/mask-border-slice.json b/testing/data/property__mask-border-slice.json
similarity index 100%
rename from testing/data/mask-border-slice.json
rename to testing/data/property__mask-border-slice.json
diff --git a/testing/data/mask-border-source.json b/testing/data/property__mask-border-source.json
similarity index 100%
rename from testing/data/mask-border-source.json
rename to testing/data/property__mask-border-source.json
diff --git a/testing/data/mask-border-width.json b/testing/data/property__mask-border-width.json
similarity index 100%
rename from testing/data/mask-border-width.json
rename to testing/data/property__mask-border-width.json
diff --git a/testing/data/mask-border.json b/testing/data/property__mask-border.json
similarity index 100%
rename from testing/data/mask-border.json
rename to testing/data/property__mask-border.json
diff --git a/testing/data/mask-clip.json b/testing/data/property__mask-clip.json
similarity index 100%
rename from testing/data/mask-clip.json
rename to testing/data/property__mask-clip.json
diff --git a/testing/data/mask-composite.json b/testing/data/property__mask-composite.json
similarity index 100%
rename from testing/data/mask-composite.json
rename to testing/data/property__mask-composite.json
diff --git a/testing/data/mask-image.json b/testing/data/property__mask-image.json
similarity index 100%
rename from testing/data/mask-image.json
rename to testing/data/property__mask-image.json
diff --git a/testing/data/mask-mode.json b/testing/data/property__mask-mode.json
similarity index 100%
rename from testing/data/mask-mode.json
rename to testing/data/property__mask-mode.json
diff --git a/testing/data/mask-origin.json b/testing/data/property__mask-origin.json
similarity index 100%
rename from testing/data/mask-origin.json
rename to testing/data/property__mask-origin.json
diff --git a/testing/data/mask-position.json b/testing/data/property__mask-position.json
similarity index 100%
rename from testing/data/mask-position.json
rename to testing/data/property__mask-position.json
diff --git a/testing/data/mask-repeat.json b/testing/data/property__mask-repeat.json
similarity index 100%
rename from testing/data/mask-repeat.json
rename to testing/data/property__mask-repeat.json
diff --git a/testing/data/mask-size.json b/testing/data/property__mask-size.json
similarity index 100%
rename from testing/data/mask-size.json
rename to testing/data/property__mask-size.json
diff --git a/testing/data/mask-type.json b/testing/data/property__mask-type.json
similarity index 100%
rename from testing/data/mask-type.json
rename to testing/data/property__mask-type.json
diff --git a/testing/data/mask.json b/testing/data/property__mask.json
similarity index 100%
rename from testing/data/mask.json
rename to testing/data/property__mask.json
diff --git a/testing/data/masonry-auto-flow.json b/testing/data/property__masonry-auto-flow.json
similarity index 100%
rename from testing/data/masonry-auto-flow.json
rename to testing/data/property__masonry-auto-flow.json
diff --git a/testing/data/math-depth.json b/testing/data/property__math-depth.json
similarity index 100%
rename from testing/data/math-depth.json
rename to testing/data/property__math-depth.json
diff --git a/testing/data/math-shift.json b/testing/data/property__math-shift.json
similarity index 100%
rename from testing/data/math-shift.json
rename to testing/data/property__math-shift.json
diff --git a/testing/data/math-style.json b/testing/data/property__math-style.json
similarity index 100%
rename from testing/data/math-style.json
rename to testing/data/property__math-style.json
diff --git a/testing/data/max-block-size.json b/testing/data/property__max-block-size.json
similarity index 54%
rename from testing/data/max-block-size.json
rename to testing/data/property__max-block-size.json
index 8d83782..dfb0a84 100644
--- a/testing/data/max-block-size.json
+++ b/testing/data/property__max-block-size.json
@@ -1,6 +1,6 @@
 {
   "name": "max-block-size",
   "type": "property",
-  "syntax": "<'max-width'>",
+  "syntax": "<'max-width'> | stretch | fit-content | contain",
   "constituents": []
 }
\ No newline at end of file
diff --git a/testing/data/max-height.json b/testing/data/property__max-height.json
similarity index 71%
rename from testing/data/max-height.json
rename to testing/data/property__max-height.json
index e7be233..23744b7 100644
--- a/testing/data/max-height.json
+++ b/testing/data/property__max-height.json
@@ -1,7 +1,7 @@
 {
   "name": "max-height",
   "type": "property",
-  "syntax": "none | <length-percentage [0,∞]> | min-content | max-content | fit-content(<length-percentage [0,∞]>)",
+  "syntax": "none | <length-percentage [0,∞]> | min-content | max-content | fit-content(<length-percentage [0,∞]>) | stretch | fit-content | contain",
   "constituents": [
     {
       "type": "length-percentage",
diff --git a/testing/data/max-inline-size.json b/testing/data/property__max-inline-size.json
similarity index 54%
rename from testing/data/max-inline-size.json
rename to testing/data/property__max-inline-size.json
index 465530f..b400f6a 100644
--- a/testing/data/max-inline-size.json
+++ b/testing/data/property__max-inline-size.json
@@ -1,6 +1,6 @@
 {
   "name": "max-inline-size",
   "type": "property",
-  "syntax": "<'max-width'>",
+  "syntax": "<'max-width'> | stretch | fit-content | contain",
   "constituents": []
 }
\ No newline at end of file
diff --git a/testing/data/max-width.json b/testing/data/property__max-width.json
similarity index 71%
rename from testing/data/max-width.json
rename to testing/data/property__max-width.json
index ffb2bd5..07bb078 100644
--- a/testing/data/max-width.json
+++ b/testing/data/property__max-width.json
@@ -1,7 +1,7 @@
 {
   "name": "max-width",
   "type": "property",
-  "syntax": "none | <length-percentage [0,∞]> | min-content | max-content | fit-content(<length-percentage [0,∞]>)",
+  "syntax": "none | <length-percentage [0,∞]> | min-content | max-content | fit-content(<length-percentage [0,∞]>) | stretch | fit-content | contain",
   "constituents": [
     {
       "type": "length-percentage",
diff --git a/testing/data/min-block-size.json b/testing/data/property__min-block-size.json
similarity index 54%
rename from testing/data/min-block-size.json
rename to testing/data/property__min-block-size.json
index 4707af1..cca75ef 100644
--- a/testing/data/min-block-size.json
+++ b/testing/data/property__min-block-size.json
@@ -1,6 +1,6 @@
 {
   "name": "min-block-size",
   "type": "property",
-  "syntax": "<'min-width'>",
+  "syntax": "<'min-width'> | stretch | fit-content | contain",
   "constituents": []
 }
\ No newline at end of file
diff --git a/testing/data/min-height.json b/testing/data/property__min-height.json
similarity index 71%
rename from testing/data/min-height.json
rename to testing/data/property__min-height.json
index 3ecc3c8..5382f91 100644
--- a/testing/data/min-height.json
+++ b/testing/data/property__min-height.json
@@ -1,7 +1,7 @@
 {
   "name": "min-height",
   "type": "property",
-  "syntax": "auto | <length-percentage [0,∞]> | min-content | max-content | fit-content(<length-percentage [0,∞]>)",
+  "syntax": "auto | <length-percentage [0,∞]> | min-content | max-content | fit-content(<length-percentage [0,∞]>) | stretch | fit-content | contain",
   "constituents": [
     {
       "type": "length-percentage",
diff --git a/testing/data/min-inline-size.json b/testing/data/property__min-inline-size.json
similarity index 54%
rename from testing/data/min-inline-size.json
rename to testing/data/property__min-inline-size.json
index d3cc598..af87a25 100644
--- a/testing/data/min-inline-size.json
+++ b/testing/data/property__min-inline-size.json
@@ -1,6 +1,6 @@
 {
   "name": "min-inline-size",
   "type": "property",
-  "syntax": "<'min-width'>",
+  "syntax": "<'min-width'> | stretch | fit-content | contain",
   "constituents": []
 }
\ No newline at end of file
diff --git a/testing/data/min-width.json b/testing/data/property__min-width.json
similarity index 71%
rename from testing/data/min-width.json
rename to testing/data/property__min-width.json
index 062283d..898603e 100644
--- a/testing/data/min-width.json
+++ b/testing/data/property__min-width.json
@@ -1,7 +1,7 @@
 {
   "name": "min-width",
   "type": "property",
-  "syntax": "auto | <length-percentage [0,∞]> | min-content | max-content | fit-content(<length-percentage [0,∞]>)",
+  "syntax": "auto | <length-percentage [0,∞]> | min-content | max-content | fit-content(<length-percentage [0,∞]>) | stretch | fit-content | contain",
   "constituents": [
     {
       "type": "length-percentage",
diff --git a/testing/data/mix-blend-mode.json b/testing/data/property__mix-blend-mode.json
similarity index 100%
rename from testing/data/mix-blend-mode.json
rename to testing/data/property__mix-blend-mode.json
diff --git a/testing/data/object-fit.json b/testing/data/property__object-fit.json
similarity index 100%
rename from testing/data/object-fit.json
rename to testing/data/property__object-fit.json
diff --git a/testing/data/object-position.json b/testing/data/property__object-position.json
similarity index 100%
rename from testing/data/object-position.json
rename to testing/data/property__object-position.json
diff --git a/testing/data/offset-anchor.json b/testing/data/property__offset-anchor.json
similarity index 100%
rename from testing/data/offset-anchor.json
rename to testing/data/property__offset-anchor.json
diff --git a/testing/data/offset-distance.json b/testing/data/property__offset-distance.json
similarity index 100%
rename from testing/data/offset-distance.json
rename to testing/data/property__offset-distance.json
diff --git a/testing/data/offset-path.json b/testing/data/property__offset-path.json
similarity index 78%
rename from testing/data/offset-path.json
rename to testing/data/property__offset-path.json
index e89ea34..c1d0934 100644
--- a/testing/data/offset-path.json
+++ b/testing/data/property__offset-path.json
@@ -19,6 +19,14 @@
       "type": "url",
       "syntax": "<url()> | <src()>"
     },
+    {
+      "type": "basic-shape",
+      "syntax": "<inset()> | <xywh()> | <rect()> | <circle()> | <ellipse()> | <polygon()> | <path()>"
+    },
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    },
     {
       "type": "ray-size",
       "syntax": "closest-side | closest-corner | farthest-side | farthest-corner | sides"
@@ -38,6 +46,10 @@
     {
       "type": "length-percentage",
       "syntax": "[ <length> | <percentage> ]"
+    },
+    {
+      "type": "shape-radius",
+      "syntax": "<length-percentage [0,∞]> | closest-side | farthest-side"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/offset-position.json b/testing/data/property__offset-position.json
similarity index 100%
rename from testing/data/offset-position.json
rename to testing/data/property__offset-position.json
diff --git a/testing/data/property__offset-rotate.json b/testing/data/property__offset-rotate.json
new file mode 100644
index 0000000..3d5cbf0
--- /dev/null
+++ b/testing/data/property__offset-rotate.json
@@ -0,0 +1,11 @@
+{
+  "name": "offset-rotate",
+  "type": "property",
+  "syntax": "[ auto | reverse ] || <angle>",
+  "constituents": [
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/offset.json b/testing/data/property__offset.json
similarity index 100%
rename from testing/data/offset.json
rename to testing/data/property__offset.json
diff --git a/testing/data/opacity.json b/testing/data/property__opacity.json
similarity index 100%
rename from testing/data/opacity.json
rename to testing/data/property__opacity.json
diff --git a/testing/data/order.json b/testing/data/property__order.json
similarity index 100%
rename from testing/data/order.json
rename to testing/data/property__order.json
diff --git a/testing/data/orphans.json b/testing/data/property__orphans.json
similarity index 100%
rename from testing/data/orphans.json
rename to testing/data/property__orphans.json
diff --git a/testing/data/outline-color.json b/testing/data/property__outline-color.json
similarity index 89%
rename from testing/data/outline-color.json
rename to testing/data/property__outline-color.json
index 2addf05..84e4329 100644
--- a/testing/data/outline-color.json
+++ b/testing/data/property__outline-color.json
@@ -18,6 +18,10 @@
     {
       "type": "length-percentage",
       "syntax": "[ <length> | <percentage> ]"
+    },
+    {
+      "type": "flex",
+      "syntax": "<fr>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/outline-offset.json b/testing/data/property__outline-offset.json
similarity index 100%
rename from testing/data/outline-offset.json
rename to testing/data/property__outline-offset.json
diff --git a/testing/data/outline-style.json b/testing/data/property__outline-style.json
similarity index 100%
rename from testing/data/outline-style.json
rename to testing/data/property__outline-style.json
diff --git a/testing/data/outline-width.json b/testing/data/property__outline-width.json
similarity index 100%
rename from testing/data/outline-width.json
rename to testing/data/property__outline-width.json
diff --git a/testing/data/outline.json b/testing/data/property__outline.json
similarity index 100%
rename from testing/data/outline.json
rename to testing/data/property__outline.json
diff --git a/testing/data/overflow-anchor.json b/testing/data/property__overflow-anchor.json
similarity index 100%
rename from testing/data/overflow-anchor.json
rename to testing/data/property__overflow-anchor.json
diff --git a/testing/data/overflow-block.json b/testing/data/property__overflow-block.json
similarity index 100%
rename from testing/data/overflow-block.json
rename to testing/data/property__overflow-block.json
diff --git a/testing/data/overflow-clip-margin.json b/testing/data/property__overflow-clip-margin.json
similarity index 100%
rename from testing/data/overflow-clip-margin.json
rename to testing/data/property__overflow-clip-margin.json
diff --git a/testing/data/overflow-inline.json b/testing/data/property__overflow-inline.json
similarity index 100%
rename from testing/data/overflow-inline.json
rename to testing/data/property__overflow-inline.json
diff --git a/testing/data/overflow-wrap.json b/testing/data/property__overflow-wrap.json
similarity index 100%
rename from testing/data/overflow-wrap.json
rename to testing/data/property__overflow-wrap.json
diff --git a/testing/data/overflow-x.json b/testing/data/property__overflow-x.json
similarity index 100%
rename from testing/data/overflow-x.json
rename to testing/data/property__overflow-x.json
diff --git a/testing/data/overflow-y.json b/testing/data/property__overflow-y.json
similarity index 100%
rename from testing/data/overflow-y.json
rename to testing/data/property__overflow-y.json
diff --git a/testing/data/overflow.json b/testing/data/property__overflow.json
similarity index 100%
rename from testing/data/overflow.json
rename to testing/data/property__overflow.json
diff --git a/testing/data/overscroll-behavior-block.json b/testing/data/property__overscroll-behavior-block.json
similarity index 100%
rename from testing/data/overscroll-behavior-block.json
rename to testing/data/property__overscroll-behavior-block.json
diff --git a/testing/data/overscroll-behavior-inline.json b/testing/data/property__overscroll-behavior-inline.json
similarity index 100%
rename from testing/data/overscroll-behavior-inline.json
rename to testing/data/property__overscroll-behavior-inline.json
diff --git a/testing/data/overscroll-behavior-x.json b/testing/data/property__overscroll-behavior-x.json
similarity index 100%
rename from testing/data/overscroll-behavior-x.json
rename to testing/data/property__overscroll-behavior-x.json
diff --git a/testing/data/overscroll-behavior-y.json b/testing/data/property__overscroll-behavior-y.json
similarity index 100%
rename from testing/data/overscroll-behavior-y.json
rename to testing/data/property__overscroll-behavior-y.json
diff --git a/testing/data/overscroll-behavior.json b/testing/data/property__overscroll-behavior.json
similarity index 100%
rename from testing/data/overscroll-behavior.json
rename to testing/data/property__overscroll-behavior.json
diff --git a/testing/data/padding-block-end.json b/testing/data/property__padding-block-end.json
similarity index 100%
rename from testing/data/padding-block-end.json
rename to testing/data/property__padding-block-end.json
diff --git a/testing/data/padding-block-start.json b/testing/data/property__padding-block-start.json
similarity index 100%
rename from testing/data/padding-block-start.json
rename to testing/data/property__padding-block-start.json
diff --git a/testing/data/padding-block.json b/testing/data/property__padding-block.json
similarity index 100%
rename from testing/data/padding-block.json
rename to testing/data/property__padding-block.json
diff --git a/testing/data/padding-bottom.json b/testing/data/property__padding-bottom.json
similarity index 100%
rename from testing/data/padding-bottom.json
rename to testing/data/property__padding-bottom.json
diff --git a/testing/data/padding-inline-end.json b/testing/data/property__padding-inline-end.json
similarity index 100%
rename from testing/data/padding-inline-end.json
rename to testing/data/property__padding-inline-end.json
diff --git a/testing/data/padding-inline-start.json b/testing/data/property__padding-inline-start.json
similarity index 100%
rename from testing/data/padding-inline-start.json
rename to testing/data/property__padding-inline-start.json
diff --git a/testing/data/padding-inline.json b/testing/data/property__padding-inline.json
similarity index 100%
rename from testing/data/padding-inline.json
rename to testing/data/property__padding-inline.json
diff --git a/testing/data/padding-left.json b/testing/data/property__padding-left.json
similarity index 100%
rename from testing/data/padding-left.json
rename to testing/data/property__padding-left.json
diff --git a/testing/data/padding-right.json b/testing/data/property__padding-right.json
similarity index 100%
rename from testing/data/padding-right.json
rename to testing/data/property__padding-right.json
diff --git a/testing/data/padding-top.json b/testing/data/property__padding-top.json
similarity index 100%
rename from testing/data/padding-top.json
rename to testing/data/property__padding-top.json
diff --git a/testing/data/padding.json b/testing/data/property__padding.json
similarity index 100%
rename from testing/data/padding.json
rename to testing/data/property__padding.json
diff --git a/testing/data/page-break-after.json b/testing/data/property__page-break-after.json
similarity index 100%
rename from testing/data/page-break-after.json
rename to testing/data/property__page-break-after.json
diff --git a/testing/data/page-break-before.json b/testing/data/property__page-break-before.json
similarity index 100%
rename from testing/data/page-break-before.json
rename to testing/data/property__page-break-before.json
diff --git a/testing/data/page-break-inside.json b/testing/data/property__page-break-inside.json
similarity index 100%
rename from testing/data/page-break-inside.json
rename to testing/data/property__page-break-inside.json
diff --git a/testing/data/page.json b/testing/data/property__page.json
similarity index 100%
rename from testing/data/page.json
rename to testing/data/property__page.json
diff --git a/testing/data/paint-order.json b/testing/data/property__paint-order.json
similarity index 100%
rename from testing/data/paint-order.json
rename to testing/data/property__paint-order.json
diff --git a/testing/data/perspective-origin.json b/testing/data/property__perspective-origin.json
similarity index 100%
rename from testing/data/perspective-origin.json
rename to testing/data/property__perspective-origin.json
diff --git a/testing/data/perspective.json b/testing/data/property__perspective.json
similarity index 100%
rename from testing/data/perspective.json
rename to testing/data/property__perspective.json
diff --git a/testing/data/place-content.json b/testing/data/property__place-content.json
similarity index 100%
rename from testing/data/place-content.json
rename to testing/data/property__place-content.json
diff --git a/testing/data/place-items.json b/testing/data/property__place-items.json
similarity index 100%
rename from testing/data/place-items.json
rename to testing/data/property__place-items.json
diff --git a/testing/data/place-self.json b/testing/data/property__place-self.json
similarity index 100%
rename from testing/data/place-self.json
rename to testing/data/property__place-self.json
diff --git a/testing/data/pointer-events.json b/testing/data/property__pointer-events.json
similarity index 100%
rename from testing/data/pointer-events.json
rename to testing/data/property__pointer-events.json
diff --git a/testing/data/position.json b/testing/data/property__position.json
similarity index 100%
rename from testing/data/position.json
rename to testing/data/property__position.json
diff --git a/testing/data/print-color-adjust.json b/testing/data/property__print-color-adjust.json
similarity index 100%
rename from testing/data/print-color-adjust.json
rename to testing/data/property__print-color-adjust.json
diff --git a/testing/data/quotes.json b/testing/data/property__quotes.json
similarity index 100%
rename from testing/data/quotes.json
rename to testing/data/property__quotes.json
diff --git a/testing/data/resize.json b/testing/data/property__resize.json
similarity index 100%
rename from testing/data/resize.json
rename to testing/data/property__resize.json
diff --git a/testing/data/right.json b/testing/data/property__right.json
similarity index 100%
rename from testing/data/right.json
rename to testing/data/property__right.json
diff --git a/testing/data/rotate.json b/testing/data/property__rotate.json
similarity index 51%
rename from testing/data/rotate.json
rename to testing/data/property__rotate.json
index ea85e30..5725830 100644
--- a/testing/data/rotate.json
+++ b/testing/data/property__rotate.json
@@ -2,5 +2,10 @@
   "name": "rotate",
   "type": "property",
   "syntax": "none | <angle> | [ x | y | z | <number>{3} ] && <angle>",
-  "constituents": []
+  "constituents": [
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    }
+  ]
 }
\ No newline at end of file
diff --git a/testing/data/row-gap.json b/testing/data/property__row-gap.json
similarity index 100%
rename from testing/data/row-gap.json
rename to testing/data/property__row-gap.json
diff --git a/testing/data/ruby-align.json b/testing/data/property__ruby-align.json
similarity index 100%
rename from testing/data/ruby-align.json
rename to testing/data/property__ruby-align.json
diff --git a/testing/data/ruby-position.json b/testing/data/property__ruby-position.json
similarity index 100%
rename from testing/data/ruby-position.json
rename to testing/data/property__ruby-position.json
diff --git a/testing/data/scale.json b/testing/data/property__scale.json
similarity index 100%
rename from testing/data/scale.json
rename to testing/data/property__scale.json
diff --git a/testing/data/scroll-behavior.json b/testing/data/property__scroll-behavior.json
similarity index 100%
rename from testing/data/scroll-behavior.json
rename to testing/data/property__scroll-behavior.json
diff --git a/testing/data/scroll-margin-block-end.json b/testing/data/property__scroll-margin-block-end.json
similarity index 100%
rename from testing/data/scroll-margin-block-end.json
rename to testing/data/property__scroll-margin-block-end.json
diff --git a/testing/data/scroll-margin-block-start.json b/testing/data/property__scroll-margin-block-start.json
similarity index 100%
rename from testing/data/scroll-margin-block-start.json
rename to testing/data/property__scroll-margin-block-start.json
diff --git a/testing/data/scroll-margin-block.json b/testing/data/property__scroll-margin-block.json
similarity index 100%
rename from testing/data/scroll-margin-block.json
rename to testing/data/property__scroll-margin-block.json
diff --git a/testing/data/scroll-margin-bottom.json b/testing/data/property__scroll-margin-bottom.json
similarity index 100%
rename from testing/data/scroll-margin-bottom.json
rename to testing/data/property__scroll-margin-bottom.json
diff --git a/testing/data/scroll-margin-inline-end.json b/testing/data/property__scroll-margin-inline-end.json
similarity index 100%
rename from testing/data/scroll-margin-inline-end.json
rename to testing/data/property__scroll-margin-inline-end.json
diff --git a/testing/data/scroll-margin-inline-start.json b/testing/data/property__scroll-margin-inline-start.json
similarity index 100%
rename from testing/data/scroll-margin-inline-start.json
rename to testing/data/property__scroll-margin-inline-start.json
diff --git a/testing/data/scroll-margin-inline.json b/testing/data/property__scroll-margin-inline.json
similarity index 100%
rename from testing/data/scroll-margin-inline.json
rename to testing/data/property__scroll-margin-inline.json
diff --git a/testing/data/scroll-margin-left.json b/testing/data/property__scroll-margin-left.json
similarity index 100%
rename from testing/data/scroll-margin-left.json
rename to testing/data/property__scroll-margin-left.json
diff --git a/testing/data/scroll-margin-right.json b/testing/data/property__scroll-margin-right.json
similarity index 100%
rename from testing/data/scroll-margin-right.json
rename to testing/data/property__scroll-margin-right.json
diff --git a/testing/data/scroll-margin-top.json b/testing/data/property__scroll-margin-top.json
similarity index 100%
rename from testing/data/scroll-margin-top.json
rename to testing/data/property__scroll-margin-top.json
diff --git a/testing/data/scroll-margin.json b/testing/data/property__scroll-margin.json
similarity index 100%
rename from testing/data/scroll-margin.json
rename to testing/data/property__scroll-margin.json
diff --git a/testing/data/scroll-padding-block-end.json b/testing/data/property__scroll-padding-block-end.json
similarity index 100%
rename from testing/data/scroll-padding-block-end.json
rename to testing/data/property__scroll-padding-block-end.json
diff --git a/testing/data/scroll-padding-block-start.json b/testing/data/property__scroll-padding-block-start.json
similarity index 100%
rename from testing/data/scroll-padding-block-start.json
rename to testing/data/property__scroll-padding-block-start.json
diff --git a/testing/data/scroll-padding-block.json b/testing/data/property__scroll-padding-block.json
similarity index 100%
rename from testing/data/scroll-padding-block.json
rename to testing/data/property__scroll-padding-block.json
diff --git a/testing/data/scroll-padding-bottom.json b/testing/data/property__scroll-padding-bottom.json
similarity index 100%
rename from testing/data/scroll-padding-bottom.json
rename to testing/data/property__scroll-padding-bottom.json
diff --git a/testing/data/scroll-padding-inline-end.json b/testing/data/property__scroll-padding-inline-end.json
similarity index 100%
rename from testing/data/scroll-padding-inline-end.json
rename to testing/data/property__scroll-padding-inline-end.json
diff --git a/testing/data/scroll-padding-inline-start.json b/testing/data/property__scroll-padding-inline-start.json
similarity index 100%
rename from testing/data/scroll-padding-inline-start.json
rename to testing/data/property__scroll-padding-inline-start.json
diff --git a/testing/data/scroll-padding-inline.json b/testing/data/property__scroll-padding-inline.json
similarity index 100%
rename from testing/data/scroll-padding-inline.json
rename to testing/data/property__scroll-padding-inline.json
diff --git a/testing/data/scroll-padding-left.json b/testing/data/property__scroll-padding-left.json
similarity index 100%
rename from testing/data/scroll-padding-left.json
rename to testing/data/property__scroll-padding-left.json
diff --git a/testing/data/scroll-padding-right.json b/testing/data/property__scroll-padding-right.json
similarity index 100%
rename from testing/data/scroll-padding-right.json
rename to testing/data/property__scroll-padding-right.json
diff --git a/testing/data/scroll-padding-top.json b/testing/data/property__scroll-padding-top.json
similarity index 100%
rename from testing/data/scroll-padding-top.json
rename to testing/data/property__scroll-padding-top.json
diff --git a/testing/data/scroll-padding.json b/testing/data/property__scroll-padding.json
similarity index 100%
rename from testing/data/scroll-padding.json
rename to testing/data/property__scroll-padding.json
diff --git a/testing/data/scroll-snap-align.json b/testing/data/property__scroll-snap-align.json
similarity index 100%
rename from testing/data/scroll-snap-align.json
rename to testing/data/property__scroll-snap-align.json
diff --git a/testing/data/scroll-snap-stop.json b/testing/data/property__scroll-snap-stop.json
similarity index 100%
rename from testing/data/scroll-snap-stop.json
rename to testing/data/property__scroll-snap-stop.json
diff --git a/testing/data/scroll-snap-type.json b/testing/data/property__scroll-snap-type.json
similarity index 100%
rename from testing/data/scroll-snap-type.json
rename to testing/data/property__scroll-snap-type.json
diff --git a/testing/data/scroll-timeline-axis.json b/testing/data/property__scroll-timeline-axis.json
similarity index 100%
rename from testing/data/scroll-timeline-axis.json
rename to testing/data/property__scroll-timeline-axis.json
diff --git a/testing/data/scroll-timeline-name.json b/testing/data/property__scroll-timeline-name.json
similarity index 100%
rename from testing/data/scroll-timeline-name.json
rename to testing/data/property__scroll-timeline-name.json
diff --git a/testing/data/scroll-timeline.json b/testing/data/property__scroll-timeline.json
similarity index 100%
rename from testing/data/scroll-timeline.json
rename to testing/data/property__scroll-timeline.json
diff --git a/testing/data/scrollbar-color.json b/testing/data/property__scrollbar-color.json
similarity index 100%
rename from testing/data/scrollbar-color.json
rename to testing/data/property__scrollbar-color.json
diff --git a/testing/data/scrollbar-gutter.json b/testing/data/property__scrollbar-gutter.json
similarity index 100%
rename from testing/data/scrollbar-gutter.json
rename to testing/data/property__scrollbar-gutter.json
diff --git a/testing/data/scrollbar-width.json b/testing/data/property__scrollbar-width.json
similarity index 100%
rename from testing/data/scrollbar-width.json
rename to testing/data/property__scrollbar-width.json
diff --git a/testing/data/shape-image-threshold.json b/testing/data/property__shape-image-threshold.json
similarity index 100%
rename from testing/data/shape-image-threshold.json
rename to testing/data/property__shape-image-threshold.json
diff --git a/testing/data/shape-margin.json b/testing/data/property__shape-margin.json
similarity index 100%
rename from testing/data/shape-margin.json
rename to testing/data/property__shape-margin.json
diff --git a/testing/data/property__shape-outside.json b/testing/data/property__shape-outside.json
new file mode 100644
index 0000000..5ace7fa
--- /dev/null
+++ b/testing/data/property__shape-outside.json
@@ -0,0 +1,47 @@
+{
+  "name": "shape-outside",
+  "type": "property",
+  "syntax": "none | [ <basic-shape> || <shape-box> ] | <image>",
+  "constituents": [
+    {
+      "type": "basic-shape",
+      "syntax": "<inset()> | <xywh()> | <rect()> | <circle()> | <ellipse()> | <polygon()> | <path()>"
+    },
+    {
+      "type": "shape-box",
+      "syntax": "<box> | margin-box"
+    },
+    {
+      "type": "image",
+      "syntax": "<url> | <gradient>"
+    },
+    {
+      "type": "length-percentage",
+      "syntax": "[ <length> | <percentage> ]"
+    },
+    {
+      "type": "shape-radius",
+      "syntax": "<length-percentage [0,∞]> | closest-side | farthest-side"
+    },
+    {
+      "type": "position",
+      "syntax": "[ [ left | center | right ] || [ top | center | bottom ] | [ left | center | right | <length-percentage> ] [ top | center | bottom | <length-percentage> ]? | [ [ left | right ] <length-percentage> ] && [ [ top | bottom ] <length-percentage> ] ]"
+    },
+    {
+      "type": "box",
+      "syntax": "border-box | padding-box | content-box"
+    },
+    {
+      "type": "url",
+      "syntax": "<url()> | <src()>"
+    },
+    {
+      "type": "url()",
+      "syntax": "url( <string> <url-modifier>* ) | <url-token>"
+    },
+    {
+      "type": "src()",
+      "syntax": "src( <string> <url-modifier>* )"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/tab-size.json b/testing/data/property__tab-size.json
similarity index 100%
rename from testing/data/tab-size.json
rename to testing/data/property__tab-size.json
diff --git a/testing/data/table-layout.json b/testing/data/property__table-layout.json
similarity index 100%
rename from testing/data/table-layout.json
rename to testing/data/property__table-layout.json
diff --git a/testing/data/text-align-last.json b/testing/data/property__text-align-last.json
similarity index 100%
rename from testing/data/text-align-last.json
rename to testing/data/property__text-align-last.json
diff --git a/testing/data/text-align.json b/testing/data/property__text-align.json
similarity index 100%
rename from testing/data/text-align.json
rename to testing/data/property__text-align.json
diff --git a/testing/data/text-combine-upright.json b/testing/data/property__text-combine-upright.json
similarity index 100%
rename from testing/data/text-combine-upright.json
rename to testing/data/property__text-combine-upright.json
diff --git a/testing/data/text-decoration-color.json b/testing/data/property__text-decoration-color.json
similarity index 100%
rename from testing/data/text-decoration-color.json
rename to testing/data/property__text-decoration-color.json
diff --git a/testing/data/text-decoration-line.json b/testing/data/property__text-decoration-line.json
similarity index 100%
rename from testing/data/text-decoration-line.json
rename to testing/data/property__text-decoration-line.json
diff --git a/testing/data/text-decoration-skip-ink.json b/testing/data/property__text-decoration-skip-ink.json
similarity index 100%
rename from testing/data/text-decoration-skip-ink.json
rename to testing/data/property__text-decoration-skip-ink.json
diff --git a/testing/data/text-decoration-skip.json b/testing/data/property__text-decoration-skip.json
similarity index 100%
rename from testing/data/text-decoration-skip.json
rename to testing/data/property__text-decoration-skip.json
diff --git a/testing/data/text-decoration-style.json b/testing/data/property__text-decoration-style.json
similarity index 100%
rename from testing/data/text-decoration-style.json
rename to testing/data/property__text-decoration-style.json
diff --git a/testing/data/text-decoration-thickness.json b/testing/data/property__text-decoration-thickness.json
similarity index 100%
rename from testing/data/text-decoration-thickness.json
rename to testing/data/property__text-decoration-thickness.json
diff --git a/testing/data/text-decoration.json b/testing/data/property__text-decoration.json
similarity index 100%
rename from testing/data/text-decoration.json
rename to testing/data/property__text-decoration.json
diff --git a/testing/data/text-emphasis-color.json b/testing/data/property__text-emphasis-color.json
similarity index 100%
rename from testing/data/text-emphasis-color.json
rename to testing/data/property__text-emphasis-color.json
diff --git a/testing/data/text-emphasis-position.json b/testing/data/property__text-emphasis-position.json
similarity index 100%
rename from testing/data/text-emphasis-position.json
rename to testing/data/property__text-emphasis-position.json
diff --git a/testing/data/text-emphasis-style.json b/testing/data/property__text-emphasis-style.json
similarity index 100%
rename from testing/data/text-emphasis-style.json
rename to testing/data/property__text-emphasis-style.json
diff --git a/testing/data/text-emphasis.json b/testing/data/property__text-emphasis.json
similarity index 100%
rename from testing/data/text-emphasis.json
rename to testing/data/property__text-emphasis.json
diff --git a/testing/data/text-indent.json b/testing/data/property__text-indent.json
similarity index 100%
rename from testing/data/text-indent.json
rename to testing/data/property__text-indent.json
diff --git a/testing/data/text-justify.json b/testing/data/property__text-justify.json
similarity index 100%
rename from testing/data/text-justify.json
rename to testing/data/property__text-justify.json
diff --git a/testing/data/text-orientation.json b/testing/data/property__text-orientation.json
similarity index 100%
rename from testing/data/text-orientation.json
rename to testing/data/property__text-orientation.json
diff --git a/testing/data/text-overflow.json b/testing/data/property__text-overflow.json
similarity index 100%
rename from testing/data/text-overflow.json
rename to testing/data/property__text-overflow.json
diff --git a/testing/data/text-rendering.json b/testing/data/property__text-rendering.json
similarity index 100%
rename from testing/data/text-rendering.json
rename to testing/data/property__text-rendering.json
diff --git a/testing/data/text-shadow.json b/testing/data/property__text-shadow.json
similarity index 100%
rename from testing/data/text-shadow.json
rename to testing/data/property__text-shadow.json
diff --git a/testing/data/text-size-adjust.json b/testing/data/property__text-size-adjust.json
similarity index 100%
rename from testing/data/text-size-adjust.json
rename to testing/data/property__text-size-adjust.json
diff --git a/testing/data/text-transform.json b/testing/data/property__text-transform.json
similarity index 77%
rename from testing/data/text-transform.json
rename to testing/data/property__text-transform.json
index dee487e..dcd29b0 100644
--- a/testing/data/text-transform.json
+++ b/testing/data/property__text-transform.json
@@ -1,6 +1,6 @@
 {
   "name": "text-transform",
   "type": "property",
-  "syntax": "none | [capitalize | uppercase | lowercase ] || full-width || full-size-kana",
+  "syntax": "none | [capitalize | uppercase | lowercase ] || full-width || full-size-kana | math-auto",
   "constituents": []
 }
\ No newline at end of file
diff --git a/testing/data/text-underline-offset.json b/testing/data/property__text-underline-offset.json
similarity index 100%
rename from testing/data/text-underline-offset.json
rename to testing/data/property__text-underline-offset.json
diff --git a/testing/data/text-underline-position.json b/testing/data/property__text-underline-position.json
similarity index 100%
rename from testing/data/text-underline-position.json
rename to testing/data/property__text-underline-position.json
diff --git a/testing/data/text-wrap.json b/testing/data/property__text-wrap.json
similarity index 100%
rename from testing/data/text-wrap.json
rename to testing/data/property__text-wrap.json
diff --git a/testing/data/timeline-scope.json b/testing/data/property__timeline-scope.json
similarity index 100%
rename from testing/data/timeline-scope.json
rename to testing/data/property__timeline-scope.json
diff --git a/testing/data/top.json b/testing/data/property__top.json
similarity index 100%
rename from testing/data/top.json
rename to testing/data/property__top.json
diff --git a/testing/data/touch-action.json b/testing/data/property__touch-action.json
similarity index 100%
rename from testing/data/touch-action.json
rename to testing/data/property__touch-action.json
diff --git a/testing/data/transform-box.json b/testing/data/property__transform-box.json
similarity index 100%
rename from testing/data/transform-box.json
rename to testing/data/property__transform-box.json
diff --git a/testing/data/transform-origin.json b/testing/data/property__transform-origin.json
similarity index 100%
rename from testing/data/transform-origin.json
rename to testing/data/property__transform-origin.json
diff --git a/testing/data/transform-style.json b/testing/data/property__transform-style.json
similarity index 100%
rename from testing/data/transform-style.json
rename to testing/data/property__transform-style.json
diff --git a/testing/data/transform.json b/testing/data/property__transform.json
similarity index 100%
rename from testing/data/transform.json
rename to testing/data/property__transform.json
diff --git a/testing/data/property__transition-delay.json b/testing/data/property__transition-delay.json
new file mode 100644
index 0000000..36b4a04
--- /dev/null
+++ b/testing/data/property__transition-delay.json
@@ -0,0 +1,11 @@
+{
+  "name": "transition-delay",
+  "type": "property",
+  "syntax": "<time>#",
+  "constituents": [
+    {
+      "type": "time",
+      "syntax": "<s> | <ms>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/transition-duration.json b/testing/data/property__transition-duration.json
similarity index 50%
rename from testing/data/transition-duration.json
rename to testing/data/property__transition-duration.json
index 9e64453..8d283eb 100644
--- a/testing/data/transition-duration.json
+++ b/testing/data/property__transition-duration.json
@@ -2,5 +2,10 @@
   "name": "transition-duration",
   "type": "property",
   "syntax": "<time [0s,∞]>#",
-  "constituents": []
+  "constituents": [
+    {
+      "type": "time",
+      "syntax": "<s> | <ms>"
+    }
+  ]
 }
\ No newline at end of file
diff --git a/testing/data/transition-property.json b/testing/data/property__transition-property.json
similarity index 100%
rename from testing/data/transition-property.json
rename to testing/data/property__transition-property.json
diff --git a/testing/data/transition-timing-function.json b/testing/data/property__transition-timing-function.json
similarity index 100%
rename from testing/data/transition-timing-function.json
rename to testing/data/property__transition-timing-function.json
diff --git a/testing/data/transition.json b/testing/data/property__transition.json
similarity index 95%
rename from testing/data/transition.json
rename to testing/data/property__transition.json
index 3b6d9f7..02a456c 100644
--- a/testing/data/transition.json
+++ b/testing/data/property__transition.json
@@ -11,6 +11,10 @@
       "type": "single-transition-property",
       "syntax": "all | <custom-ident>"
     },
+    {
+      "type": "time",
+      "syntax": "<s> | <ms>"
+    },
     {
       "type": "easing-function",
       "syntax": "linear | <linear-easing-function> | <cubic-bezier-easing-function> | <step-easing-function>"
diff --git a/testing/data/translate.json b/testing/data/property__translate.json
similarity index 100%
rename from testing/data/translate.json
rename to testing/data/property__translate.json
diff --git a/testing/data/unicode-bidi.json b/testing/data/property__unicode-bidi.json
similarity index 100%
rename from testing/data/unicode-bidi.json
rename to testing/data/property__unicode-bidi.json
diff --git a/testing/data/user-select.json b/testing/data/property__user-select.json
similarity index 100%
rename from testing/data/user-select.json
rename to testing/data/property__user-select.json
diff --git a/testing/data/vertical-align.json b/testing/data/property__vertical-align.json
similarity index 100%
rename from testing/data/vertical-align.json
rename to testing/data/property__vertical-align.json
diff --git a/testing/data/view-timeline-axis.json b/testing/data/property__view-timeline-axis.json
similarity index 100%
rename from testing/data/view-timeline-axis.json
rename to testing/data/property__view-timeline-axis.json
diff --git a/testing/data/view-timeline-inset.json b/testing/data/property__view-timeline-inset.json
similarity index 100%
rename from testing/data/view-timeline-inset.json
rename to testing/data/property__view-timeline-inset.json
diff --git a/testing/data/view-timeline-name.json b/testing/data/property__view-timeline-name.json
similarity index 100%
rename from testing/data/view-timeline-name.json
rename to testing/data/property__view-timeline-name.json
diff --git a/testing/data/view-timeline.json b/testing/data/property__view-timeline.json
similarity index 100%
rename from testing/data/view-timeline.json
rename to testing/data/property__view-timeline.json
diff --git a/testing/data/view-transition-name.json b/testing/data/property__view-transition-name.json
similarity index 100%
rename from testing/data/view-transition-name.json
rename to testing/data/property__view-transition-name.json
diff --git a/testing/data/visibility.json b/testing/data/property__visibility.json
similarity index 100%
rename from testing/data/visibility.json
rename to testing/data/property__visibility.json
diff --git a/testing/data/white-space-collapse.json b/testing/data/property__white-space-collapse.json
similarity index 100%
rename from testing/data/white-space-collapse.json
rename to testing/data/property__white-space-collapse.json
diff --git a/testing/data/white-space.json b/testing/data/property__white-space.json
similarity index 100%
rename from testing/data/white-space.json
rename to testing/data/property__white-space.json
diff --git a/testing/data/widows.json b/testing/data/property__widows.json
similarity index 100%
rename from testing/data/widows.json
rename to testing/data/property__widows.json
diff --git a/testing/data/width.json b/testing/data/property__width.json
similarity index 71%
rename from testing/data/width.json
rename to testing/data/property__width.json
index fe1d68b..72682d2 100644
--- a/testing/data/width.json
+++ b/testing/data/property__width.json
@@ -1,7 +1,7 @@
 {
   "name": "width",
   "type": "property",
-  "syntax": "auto | <length-percentage [0,∞]> | min-content | max-content | fit-content(<length-percentage [0,∞]>)",
+  "syntax": "auto | <length-percentage [0,∞]> | min-content | max-content | fit-content(<length-percentage [0,∞]>) | stretch | fit-content | contain",
   "constituents": [
     {
       "type": "length-percentage",
diff --git a/testing/data/will-change.json b/testing/data/property__will-change.json
similarity index 100%
rename from testing/data/will-change.json
rename to testing/data/property__will-change.json
diff --git a/testing/data/word-break.json b/testing/data/property__word-break.json
similarity index 100%
rename from testing/data/word-break.json
rename to testing/data/property__word-break.json
diff --git a/testing/data/word-spacing.json b/testing/data/property__word-spacing.json
similarity index 100%
rename from testing/data/word-spacing.json
rename to testing/data/property__word-spacing.json
diff --git a/testing/data/writing-mode.json b/testing/data/property__writing-mode.json
similarity index 100%
rename from testing/data/writing-mode.json
rename to testing/data/property__writing-mode.json
diff --git a/testing/data/z-index.json b/testing/data/property__z-index.json
similarity index 100%
rename from testing/data/z-index.json
rename to testing/data/property__z-index.json
diff --git a/testing/data/shape-outside.json b/testing/data/shape-outside.json
deleted file mode 100644
index 40a0853..0000000
--- a/testing/data/shape-outside.json
+++ /dev/null
@@ -1,31 +0,0 @@
-{
-  "name": "shape-outside",
-  "type": "property",
-  "syntax": "none | [ <basic-shape> || <shape-box> ] | <image>",
-  "constituents": [
-    {
-      "type": "shape-box",
-      "syntax": "<box> | margin-box"
-    },
-    {
-      "type": "image",
-      "syntax": "<url> | <gradient>"
-    },
-    {
-      "type": "box",
-      "syntax": "border-box | padding-box | content-box"
-    },
-    {
-      "type": "url",
-      "syntax": "<url()> | <src()>"
-    },
-    {
-      "type": "url()",
-      "syntax": "url( <string> <url-modifier>* ) | <url-token>"
-    },
-    {
-      "type": "src()",
-      "syntax": "src( <string> <url-modifier>* )"
-    }
-  ]
-}
\ No newline at end of file
diff --git a/testing/data/transform-function__rotate.json b/testing/data/transform-function__rotate.json
deleted file mode 100644
index f335397..0000000
--- a/testing/data/transform-function__rotate.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "rotate",
-  "type": "function",
-  "syntax": "rotate( [ <angle> | <zero> ] )",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/transition-delay.json b/testing/data/transition-delay.json
deleted file mode 100644
index 7b49455..0000000
--- a/testing/data/transition-delay.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "name": "transition-delay",
-  "type": "property",
-  "syntax": "<time>#",
-  "constituents": []
-}
\ No newline at end of file
diff --git a/testing/data/alpha-value.json b/testing/data/type__alpha-value.json
similarity index 100%
rename from testing/data/alpha-value.json
rename to testing/data/type__alpha-value.json
diff --git a/testing/data/type__angle-percentage.json b/testing/data/type__angle-percentage.json
new file mode 100644
index 0000000..0d836ac
--- /dev/null
+++ b/testing/data/type__angle-percentage.json
@@ -0,0 +1,11 @@
+{
+  "name": "angle-percentage",
+  "type": "type",
+  "syntax": "[ <angle> | <percentage> ]",
+  "constituents": [
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/blend-mode.json b/testing/data/type__blend-mode.json
similarity index 100%
rename from testing/data/blend-mode.json
rename to testing/data/type__blend-mode.json
diff --git a/testing/data/calc-constant.json b/testing/data/type__calc-constant.json
similarity index 100%
rename from testing/data/calc-constant.json
rename to testing/data/type__calc-constant.json
diff --git a/testing/data/calc-sum.json b/testing/data/type__calc-sum.json
similarity index 100%
rename from testing/data/calc-sum.json
rename to testing/data/type__calc-sum.json
diff --git a/testing/data/color-interpolation-method.json b/testing/data/type__color-interpolation-method.json
similarity index 100%
rename from testing/data/color-interpolation-method.json
rename to testing/data/type__color-interpolation-method.json
diff --git a/testing/data/color_value.json b/testing/data/type__color_value.json
similarity index 89%
rename from testing/data/color_value.json
rename to testing/data/type__color_value.json
index 75253d7..243926c 100644
--- a/testing/data/color_value.json
+++ b/testing/data/type__color_value.json
@@ -7,6 +7,10 @@
       "type": "absolute-color-base",
       "syntax": "<hex-color> | <absolute-color-function> | <named-color> | transparent"
     },
+    {
+      "type": "system-color",
+      "syntax": "<Canvas> | <CanvasText> | <LinkText> | <VisitedText> | <ActiveText> | <ButtonFace> | <ButtonText> | <ButtonBorder> | <Field> | <FieldText> | <Highlight> | <HighlightText> | <SelectedItem> | <SelectedItemText> | <Mark> | <MarkText> | <GrayText> | <AccentColor> | <AccentColorText>"
+    },
     {
       "type": "absolute-color-function",
       "syntax": "<rgb()> | <rgba()> | <hsl()> | <hsla()> | <hwb()> | <lab()> | <lch()> | <oklab()> | <oklch()> | <color()>"
@@ -95,6 +99,10 @@
       "type": "colorspace-params",
       "syntax": "[ <predefined-rgb-params> | <xyz-params>]"
     },
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    },
     {
       "type": "predefined-rgb-params",
       "syntax": "<predefined-rgb> [ <number> | <percentage> | none ]{3}"
diff --git a/testing/data/display-box.json b/testing/data/type__display-box.json
similarity index 100%
rename from testing/data/display-box.json
rename to testing/data/type__display-box.json
diff --git a/testing/data/display-inside.json b/testing/data/type__display-inside.json
similarity index 100%
rename from testing/data/display-inside.json
rename to testing/data/type__display-inside.json
diff --git a/testing/data/display-internal.json b/testing/data/type__display-internal.json
similarity index 100%
rename from testing/data/display-internal.json
rename to testing/data/type__display-internal.json
diff --git a/testing/data/display-legacy.json b/testing/data/type__display-legacy.json
similarity index 100%
rename from testing/data/display-legacy.json
rename to testing/data/type__display-legacy.json
diff --git a/testing/data/display-listitem.json b/testing/data/type__display-listitem.json
similarity index 100%
rename from testing/data/display-listitem.json
rename to testing/data/type__display-listitem.json
diff --git a/testing/data/display-outside.json b/testing/data/type__display-outside.json
similarity index 100%
rename from testing/data/display-outside.json
rename to testing/data/type__display-outside.json
diff --git a/testing/data/easing-function.json b/testing/data/type__easing-function.json
similarity index 100%
rename from testing/data/easing-function.json
rename to testing/data/type__easing-function.json
diff --git a/testing/data/filter-function.json b/testing/data/type__filter-function.json
similarity index 93%
rename from testing/data/filter-function.json
rename to testing/data/type__filter-function.json
index 88d85d4..7598985 100644
--- a/testing/data/filter-function.json
+++ b/testing/data/type__filter-function.json
@@ -42,6 +42,10 @@
     {
       "type": "saturate()",
       "syntax": "saturate( [ <number> | <percentage> ]? )"
+    },
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
     }
   ]
 }
\ No newline at end of file
diff --git a/testing/data/frequency-percentage.json b/testing/data/type__frequency-percentage.json
similarity index 51%
rename from testing/data/frequency-percentage.json
rename to testing/data/type__frequency-percentage.json
index 5d06d11..978bc3a 100644
--- a/testing/data/frequency-percentage.json
+++ b/testing/data/type__frequency-percentage.json
@@ -2,5 +2,10 @@
   "name": "frequency-percentage",
   "type": "type",
   "syntax": "[ <frequency> | <percentage> ]",
-  "constituents": []
+  "constituents": [
+    {
+      "type": "frequency",
+      "syntax": "<Hz> | <kHz>"
+    }
+  ]
 }
\ No newline at end of file
diff --git a/testing/data/gradient.json b/testing/data/type__gradient.json
similarity index 96%
rename from testing/data/gradient.json
rename to testing/data/type__gradient.json
index 56172dd..4e0c1a6 100644
--- a/testing/data/gradient.json
+++ b/testing/data/type__gradient.json
@@ -27,6 +27,10 @@
       "type": "radial-gradient-syntax",
       "syntax": "[ <rg-ending-shape> || <rg-size> ]? [ at <position> ]? , <color-stop-list>"
     },
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    },
     {
       "type": "side-or-corner",
       "syntax": "[left | right] || [top | bottom]"
diff --git a/testing/data/hue-interpolation-method.json b/testing/data/type__hue-interpolation-method.json
similarity index 100%
rename from testing/data/hue-interpolation-method.json
rename to testing/data/type__hue-interpolation-method.json
diff --git a/testing/data/type__hue.json b/testing/data/type__hue.json
new file mode 100644
index 0000000..9c79c78
--- /dev/null
+++ b/testing/data/type__hue.json
@@ -0,0 +1,11 @@
+{
+  "name": "hue",
+  "type": "type",
+  "syntax": "<number> | <angle>",
+  "constituents": [
+    {
+      "type": "angle",
+      "syntax": "<deg> | <grad> | <rad> | <turn>"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/testing/data/image.json b/testing/data/type__image.json
similarity index 100%
rename from testing/data/image.json
rename to testing/data/type__image.json
diff --git a/testing/data/length-percentage.json b/testing/data/type__length-percentage.json
similarity index 100%
rename from testing/data/length-percentage.json
rename to testing/data/type__length-percentage.json
diff --git a/testing/data/line-style.json b/testing/data/type__line-style.json
similarity index 100%
rename from testing/data/line-style.json
rename to testing/data/type__line-style.json
diff --git a/testing/data/position_value.json b/testing/data/type__position_value.json
similarity index 100%
rename from testing/data/position_value.json
rename to testing/data/type__position_value.json
diff --git a/testing/data/ratio.json b/testing/data/type__ratio.json
similarity index 100%
rename from testing/data/ratio.json
rename to testing/data/type__ratio.json
diff --git a/testing/data/time-percentage.json b/testing/data/type__time-percentage.json
similarity index 51%
rename from testing/data/time-percentage.json
rename to testing/data/type__time-percentage.json
index e805570..4fb7d7b 100644
--- a/testing/data/time-percentage.json
+++ b/testing/data/type__time-percentage.json
@@ -2,5 +2,10 @@
   "name": "time-percentage",
   "type": "type",
   "syntax": "[ <time> | <percentage> ]",
-  "constituents": []
+  "constituents": [
+    {
+      "type": "time",
+      "syntax": "<s> | <ms>"
+    }
+  ]
 }
\ No newline at end of file
diff --git a/testing/populate-from-content.js b/testing/populate-from-content.js
index e910d8a..bbdd3b3 100644
--- a/testing/populate-from-content.js
+++ b/testing/populate-from-content.js
@@ -1,3 +1,8 @@
+/*
+  This script adds/updates syntax for all the CSS features documented in mdn/content repo.
+*/
+
+/* eslint-disable-next-line n/no-unsupported-features/node-builtins */
 import fs from "node:fs/promises";
 import * as Utils from "./utils.js";
 
@@ -42,9 +47,7 @@ for await (const filePath of Utils.walkSync(contentRoot)) {
         };
 
         await fs.writeFile(
-          `testing/data/${slug
-            .replace("Web/CSS/", "")
-            .replaceAll("/", "__")}.json`,
+          `testing/data/${type}__${name}.json`,
           JSON.stringify(syntax, undefined, "  ")
         );
       }
diff --git a/testing/utils.js b/testing/utils.js
index 48751e9..c6c096e 100644
--- a/testing/utils.js
+++ b/testing/utils.js
@@ -1,8 +1,9 @@
+/* eslint-disable-next-line n/no-unsupported-features/node-builtins */
 import fs from "node:fs/promises";
 import path from "node:path";
 import { getSyntax } from "../query-syntax.js";
 
-export const typesToOmit = ["<color>", "<gradient>"];
+export const typesToOmit = ["<color>", "<gradient>", "<length>"];
 
 export async function* walkSync(dir) {
   const files = await fs.readdir(dir, { withFileTypes: true });