title: How to change source of <img> tag on hover?
body: <p>I need to change <code>&lt;img&gt;</code> source URL on <code>hover</code>.</p>
  <p>I have tried this but won't work :</p>
  <p>HTML</p>
  <pre><code>&lt;img id=&quot;my-img&quot; src=&quot;http://dummyimage.com/100x100/000/fff&quot;/&gt;
  </code></pre>
  <p>CSS</p>
  <pre><code>#my-img:hover {
      content: url('http://dummyimage.com/100x100/eb00eb/fff');
  }
  </code></pre>
  <p><a href="http://jsfiddle.net/ec9gn/" rel="noreferrer">jsFiddle</a></p>
  <p>Any help would be appreciated.</p>
  <p><strong>Update:</strong></p>
  <p>This only works for Webkit / Google Chrome.</p>