40x.html

<!DOCTYPE html>
<html>

<head>
  <meta charset="UTF-8">
  <title>Error 404</title>
  <link rel="shortcut icon" href="/devtools/winforms/favicon.ico" />
  <style>
    html {
      font-family: Roboto, Helvetica, Arial, sans-serif;
      line-height: 1.5em;
    }

    .content {
      max-width: 768px;
      padding-left: 200px;
      margin: 200px auto;
      position: relative;
    }

    .ninja {
      position: absolute;
      left: 0;
      top: 0;
    }

    h1 {
      margin: 0 0 40px;
      font: 600 60px/.9 Roboto, Helvetica, Arial, sans-serif;
      letter-spacing: -.03em;
    }

    h2 {
      margin: 0 0 20px;
      font: 400 28px/1 Roboto, Helvetica, Arial, sans-serif;
      letter-spacing: -.035em;
    }

    ul {
      padding: 0 0 0 1.3em;
      margin: 0;
    }

    a,
    a:visited {
      color: #0487c4;
      text-decoration: none;
      transition: color .2s ease, opacity .2s ease;
    }

    a:hover,
    a:focus {
      color: #036c9c;
      text-decoration: underline;
    }
  </style>
</head>

<body>
  <div class="content">
    <img class="ninja" src="/devtools/winforms/images/ninja-icon.png" />
    <h1>
      Oh, no!
      <br /> It seems we've lost this page
    </h1>
    <h2>
      Things you can try:
    </h2>
    <ul>
      <li>
        <a href="#" onclick="history.go(-1); return false;">Go back</a> and try another way</li>
      <li>Head to the
        <a href="/devtools/winforms/">Documentation Homepage</a>
      </li>
      <li>Cheer up and
        <a href="http://www.telerik.com/download">try our products</a>. Some of them are free!</li>
    </ul>
  </div>
</body>

</html>