}
      span.cm-error.cm-tag { background-color: #2b2; }
    </style>
<div id=nav>
  <a href=""><h1>CodeMirror</h1><img id=logo src="../../doc/logo.png"></a>

  <ul>
    <li><a href="../../index.html">Home</a>
    <li><a href="../../doc/manual.html">Manual</a>
    <!-- <li><a href="https://github.com/codemirror/codemirror">Code</a> -->
  </ul>
  <ul>
    <li><a href="../index.html">Language modes</a>
    <li><a class=active href="#">Diff</a>
  </ul>
</div>

<article>
<h2>Diff mode</h2>
<form><textarea id="c