title: How to delete a specific element inside a div using javascript?
body: <p>I have an html code,</p>
  
  <pre><code>&lt;div id="listing"&gt;
  Text Message 
  &lt;div class="ch"&gt;ch 1&lt;/div&gt;
  &lt;button class="btn" /&gt;
  &lt;div class="ch"&gt;ch 2&lt;/div&gt;
  &lt;button class="btn" /&gt;
  &lt;div class="ch"&gt;ch 3&lt;/div&gt;
  &lt;button class="btn" /&gt;
  &lt;div class="ch"&gt;ch 4&lt;/div&gt;
  &lt;button class="btn" /&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>If a user click the button with class "btn", it will delete the "ch" div and the corresponding button. 
  for example, </p>
  
  <pre><code>&lt;div id="listing"&gt;
  Text Message 
  &lt;div class="ch"&gt;ch 1&lt;/div&gt;
  &lt;button class="btn" /&gt;
  &lt;div class="ch"&gt;ch 2&lt;/div&gt;
  &lt;button class="btn" /&gt;
  &lt;div class="ch"&gt;ch 3&lt;/div&gt;
  &lt;button class="btn" /&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>I tried to add ID of div. but It is difficult since the div with class "ch", is dynamically created.</p>
  
  <p>So I want to delete a div that only have className.</p>