title: Change four div once use setinterval() 30s
body: <p>I want to show four div once but a loop. If four div first show after the 30s then four div first hide four div next show after 30s four div first show, four div next hide and keep repeating like that. How to do it?</p>
  
  <pre><code>&lt;div class="list-div"&gt;  
      &lt;div&gt;Content&lt;/div&gt;
      &lt;div&gt;Content&lt;/div&gt;
      &lt;div&gt;Content&lt;/div&gt;
      &lt;div&gt;Content&lt;/div&gt;
      &lt;div&gt;Content1&lt;/div&gt;
      &lt;div&gt;Content1&lt;/div&gt;
      &lt;div&gt;Content1&lt;/div&gt;
      &lt;div&gt;Content1&lt;/div&gt;
  &lt;/div&gt;
  </code></pre>