title: CSS layout breaks without border on div
body: <p>I've came across with this issue several times. Still have no clue what causes this.</p>
  
  <p>Reproduce:</p>
  
  <ol>
  <li>Open <a href="http://jsbin.com/ibowed/1/edit" rel="noreferrer">http://jsbin.com/ibowed/1/edit</a></li>
  <li>In CSS panel find <code>.l-search-index .top {</code> @ line 26</li>
  <li>change <code>border: 1px solid #ff0000;</code> to <code>border: 0;</code></li>
  <li>whaaat?</li>
  </ol>
  
  <p>Browser: chrome, but I think u can try in any other..</p>
  
  <p>Please advise!</p>