title: CSS: selecting the last float <li> on the same horizontal row
body: <p>I am using the following CSS for arranging list of boxes:</p>
  
  <pre><code> li {
       display: block;
       float: left;
   }
  </code></pre>
  
  <p>I'd like to carefully tune margins of <code>&lt;li&gt;</code> items so that the last item on the row (horizontal span) would get different margins.</p>
  
  <p>Are there any CSS selectors which could target float elements based on their position?</p>