title: Different html class every 2 item
body: <p>In php I try to do this :</p>
  
  <pre><code>&lt;div class="left"&gt; some text &lt;/div&gt;
  &lt;div class="left"&gt; some text &lt;/div&gt;
  &lt;div class="right"&gt; some text &lt;/div&gt;
  &lt;div class="right"&gt; some text &lt;/div&gt;
  &lt;div class="left"&gt; some text &lt;/div&gt;
  &lt;div class="left"&gt; some text &lt;/div&gt;
  &lt;div class="right"&gt; some text &lt;/div&gt;
  &lt;div class="right"&gt; some text &lt;/div&gt;
  .
  .
  .
  </code></pre>
  
  <p>I need different class every 2 items to have different html design.</p>