title: chrome border issue
body: <p>I only have this problem in chrome. How remove the border around the image? please see the fiddle in chrome.</p>
  
  <pre><code>&lt;form&gt;
      &lt;input type="image" class="searchbox_submit search_btn" value=""&gt;
  &lt;/form&gt;
  </code></pre>
  
  <pre class="lang-css prettyprint-override"><code>form input[type=text]:focus, form input[type=password]:focus, textarea:focus {
      outline: none;
  }
  
  .search_btn {
      background: url("http://static.ak.fbcdn.net/rsrc.php/v1/yu/r/yo348KDuskF.png") no-repeat scroll 0px -200px transparent;
      height: 25px;
      width: 30px;
      outline: none;
      border: none;
      outline-width: 0;
      -webkit-appearance: none; 
  }​
  </code></pre>
  
  <p><strong>Demo:</strong> <a href="http://jsfiddle.net/TXYg6/" rel="nofollow">http://jsfiddle.net/TXYg6/</a></p>