diff --git a/index.html b/index.html
index 2c7a73d..9a20907 100644
--- a/index.html
+++ b/index.html
@@ -4,25 +4,104 @@
     <meta charset="utf-8">
     <meta name="viewport" content="width=device-width, initial-scale=1, minimum-scale=1">
     <title>Grd - A CSS grid framework using Flexbox</title>
-    <link rel="stylesheet" href="https://cdn.jsdelivr.net/highlight.js/9.4.0/styles/github.min.css">
     <link rel="stylesheet" href="https://1000ch.github.io/gh-pages.css/gh-pages.css">
     <link rel="stylesheet" href="src/grd.css">
+    <!-- Place this tag in your head or just before your close body tag. -->
+    <script defer src="https://buttons.github.io/buttons.js"></script>
+    <script defer src="https://unpkg.com/github-corner"></script>
+    <script type="module">
+      import XMarked from 'https://unpkg.com/x-marked';
+
+      customElements.define('x-marked', XMarked);
+
+      document.addEventListener('DOMContentLoaded', () => {
+        const grid = document.querySelector('#grid');
+        const align = document.querySelector('#align-items');
+        const justify = document.querySelector('#justify-content');
+
+        function onGridChange() {
+          grid.className = `Grid ${align.value} ${justify.value}`;
+        }
+        align.addEventListener('change', onGridChange);
+        justify.addEventListener('change', onGridChange);
+
+        const template = document.querySelector('#template-cell');
+        const addCell = document.querySelector('#add');
+        const removeCell = document.querySelector('#remove');
+
+        addCell.addEventListener('click', () => {
+          const cell = document.importNode(template.content, true);
+          const select = cell.querySelector('select');
+          grid.appendChild(cell);
+          select.addEventListener('change', () => {
+            select.parentNode.className = `Cell ${select.value}`;
+          });
+        });
+
+        removeCell.addEventListener('click', () => {
+          if (grid.children.length) {
+            grid.children[grid.children.length - 1].remove();
+          }
+        });
+
+        addCell.click();
+        addCell.click();
+      });
+
+      window.addEventListener('load', () => {
+        const xmarked = document.querySelector('x-marked');
+        const div = document.querySelector('div');
+        const h2 = xmarked.shadowRoot.querySelector('h2');
+        xmarked.shadowRoot.querySelector('div').insertBefore(div, h2);
+      });
+    </script>
   </head>
   <body>
-    <div class="container">
-      <h1><img src="logo.png" alt="Grd" style="width: 100%; max-width: 480px;"></h1>
+    <div>
       <!-- Place this tag where you want the button to render. -->
       <a class="github-button" href="https://github.com/1000ch/grd" data-icon="octicon-star" data-size="large" data-show-count="true" aria-label="Star 1000ch/grd on GitHub">Star</a>
       <!-- Place this tag where you want the button to render. -->
       <a class="github-button" href="https://github.com/1000ch" data-size="large" data-show-count="true" aria-label="Follow @1000ch on GitHub">Follow @1000ch</a>
-      <p>A CSS grid framework using Flexbox.</p>
-      <ul>
-        <li><strong>Simple</strong>: Provides just 2 base classes <code>Grid</code> and <code>Cell</code> and some modifiers.</li>
-        <li><strong>Light-weight</strong>: <u>Only 321 bytes</u> (Gzipped).</li>
-        <li><strong>Flexible</strong>: Easy to use Flexbox features.</li>
-      </ul>
-      <p><a href="http://caniuse.com/#search=flex">Flexible Box Layout Module</a> and <a href="http://caniuse.com/#search=calc"><code>calc()</code> as CSS unit value</a> used in Grd are available on modern browsers (Chrome, Firefox, Safari, Opera, Edge and IE11).</p>
-      <h2>Live Demo</h2>
+    </div>
+    <github-corner>
+      <a href="https://github.com/1000ch/grd">GitHub</a>
+    </github-corner>
+    <x-marked highlight class="container">
+# grd ![""](https://badge-size.herokuapp.com/1000ch/grd/master/src/grd.css.svg?compression=gzip)
+
+![""](./logo.png)
+
+A CSS grid framework using Flexbox.
+
+- **Simple**: Provides just 2 base classes `Grid` and `Cell` and some modifiers.
+- **Light-weight**: Only 321 bytes (Gzipped).
+- **Flexible**: Easy to use Flexbox features.
+
+[Flexible Box Layout Module](http://caniuse.com/#search=flex) and [`calc()` as CSS unit value](http://caniuse.com/#search=calc) used in Grd are available on modern browsers (Chrome, Firefox, Safari, Opera, Edge and IE11).
+
+If you want to use Grd with Sass, you can choose [grd-sass](https://github.com/1000ch/grd-sass) as Sass port.
+
+## Install
+
+```bash
+npm install grd
+```
+
+## Usage
+
+```html
+<div class="Grid">
+  <div class="Cell -3of12">3of12</div>
+  <div class="Cell -9of12">9of12</div>
+</div>
+```
+
+## License
+
+[MIT](https://1000ch.mit-license.org) © [Shogo Sensui](https://github.com/1000ch)
+    </x-marked>
+    <div class="container">
+      <h2>Demo</h2>
       <div style="margin-bottom: 16px;">
         &lt;div class=&quot;Grid <select id="align-items">
           <option value="" selected>-</option>
@@ -69,55 +148,6 @@ <h2>Live Demo</h2>
           &lt;/div&gt;
         </div>
       </template>
-      <h2>Install</h2>
-      <pre><code class="bash">npm install grd</code></pre>
-      <h2>Usage</h2>
-      <pre><code class="html">&lt;div class=&quot;Grid&quot;&gt;
-  &lt;div class=&quot;Cell -3of12&quot;&gt;3of12&lt;/div&gt;
-  &lt;div class=&quot;Cell -9of12&quot;&gt;9of12&lt;/div&gt;
-&lt;/div&gt;</code></pre>
-      <h2>License</h2>
-      <p><a href="https://1000ch.mit-license.org" rel="nofollow">MIT</a> © <a href="https://github.com/1000ch">Shogo Sensui</a></p>
     </div>
-    <a href="https://github.com/1000ch/grd" class="github-corner"><svg width="80" height="80" viewbox="0 0 250 250" style="fill:#151513; color:#fff; position: absolute; top: 0; border: 0; right: 0;"><path d="M0,0 L115,115 L130,115 L142,142 L250,250 L250,0 Z"></path><path d="M128.3,109.0 C113.8,99.7 119.0,89.6 119.0,89.6 C122.0,82.7 120.5,78.6 120.5,78.6 C119.2,72.0 123.4,76.3 123.4,76.3 C127.3,80.9 125.5,87.3 125.5,87.3 C122.9,97.6 130.6,101.9 134.4,103.2" fill="currentColor" style="transform-origin: 130px 106px;" class="octo-arm"></path><path d="M115.0,115.0 C114.9,115.1 118.7,116.5 119.8,115.4 L133.7,101.6 C136.9,99.2 139.9,98.4 142.2,98.6 C133.8,88.0 127.5,74.4 143.8,58.0 C148.5,53.4 154.0,51.2 159.7,51.0 C160.3,49.4 163.2,43.6 171.4,40.1 C171.4,40.1 176.1,42.5 178.8,56.2 C183.1,58.6 187.2,61.8 190.9,65.4 C194.5,69.0 197.7,73.2 200.1,77.6 C213.8,80.2 216.3,84.9 216.3,84.9 C212.7,93.1 206.9,96.0 205.4,96.6 C205.1,102.4 203.0,107.8 198.3,112.5 C181.9,128.9 168.3,122.5 157.7,114.1 C157.9,116.9 156.7,120.9 152.7,124.9 L141.0,136.5 C139.8,137.7 141.6,141.9 141.8,141.8 Z" fill="currentColor" class="octo-body"></path></svg></a><style>.github-corner:hover .octo-arm{animation:octocat-wave 560ms ease-in-out}@keyframes octocat-wave{0%,100%{transform:rotate(0)}20%,60%{transform:rotate(-25deg)}40%,80%{transform:rotate(10deg)}}@media (max-width:500px){.github-corner:hover .octo-arm{animation:none}.github-corner .octo-arm{animation:octocat-wave 560ms ease-in-out}}</style>
-    <script>
-      document.addEventListener('DOMContentLoaded', function() {
-        var grid = document.querySelector('#grid');
-        var align = document.querySelector('#align-items');
-        var justify = document.querySelector('#justify-content');
-
-        function onGridChange() {
-          grid.className = `Grid ${align.value} ${justify.value}`;
-        }
-        align.addEventListener('change', onGridChange);
-        justify.addEventListener('change', onGridChange);
-
-        var template = document.querySelector('#template-cell');
-        var add = document.querySelector('#add');
-        var remove = document.querySelector('#remove');
-
-        add.addEventListener('click', function() {
-          var cell = document.importNode(template.content, true);
-          var select = cell.querySelector('select');
-          grid.appendChild(cell);
-          select.addEventListener('change', function() {
-            select.parentNode.className = `Cell ${select.value}`;
-          });
-        });
-
-        remove.addEventListener('click', function() {
-          if (grid.children.length) {
-            grid.children[grid.children.length - 1].remove();
-          }
-        });
-
-        add.click();
-        add.click();
-      });
-    </script>
-    <script src="https://cdn.jsdelivr.net/highlight.js/9.4.0/highlight.min.js"></script>
-    <script>hljs.initHighlightingOnLoad();</script>
-    <!-- Place this tag in your head or just before your close body tag. -->
-    <script defer src="https://buttons.github.io/buttons.js"></script>
   </body>
 </html>
diff --git a/readme.markdown b/readme.markdown
index 04c0522..a06cb14 100644
--- a/readme.markdown
+++ b/readme.markdown
@@ -1,7 +1,6 @@
-![Grd](logo.png)
+# grd ![""](https://badge-size.herokuapp.com/1000ch/grd/master/src/grd.css.svg?compression=gzip)
 
-![](https://badge-size.herokuapp.com/1000ch/grd/master/src/grd.css.svg?compression=gzip)
-[![devDependency Status](https://david-dm.org/1000ch/grd/dev-status.svg)](https://david-dm.org/1000ch/grd?type=dev)
+![""](./logo.png)
 
 A CSS grid framework using Flexbox.
 
