diff --git a/app/controllers/sandbox_controller.rb b/app/controllers/sandbox_controller.rb
index 73648b60..01787906 100644
--- a/app/controllers/sandbox_controller.rb
+++ b/app/controllers/sandbox_controller.rb
@@ -1,4 +1,5 @@
+# frozen_string_literal: true
+
 class SandboxController < ApplicationController
-    def index
-    end    
-end
\ No newline at end of file
+  def index; end
+end