chromium/third_party/blink/web_tests/css2.1/t040105-atrule-04-b.html

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN">
<html>
 <head>
  <title>CSS 2.1 Test Suite: At-rules</title>
  <link rel="help" href="http://www.w3.org/TR/CSS21/syndata.html#at-rules">
  <style type="text/css">

  p { color: green; }

  @foo {};

  p { color: red; }

  </style>
 </head>
 <body>

 <p>This should be green.</p>

 </body>
</html>