<!DOCTYPE html>
<html>
  <head>
    <title>Dynamic test page</title>
    <style>
      html {
        height: 100%;
      }
      body {
        background-color: #ff00ff;
        height: 100%;
      }
    </style>
  </head>
  <body onclick="document.body.style.backgroundColor='#40e0d0'">
  </body>
</html>