title: Javascript: onClick checkbox change div color
body: <p>I've a check-box inside div. </p>
  
  <pre><code>&lt;div id="question_text_1"&gt;
    &lt;input type="checkbox" onChange="myFunction(question_text_1)"&gt;Sample question text
  &lt;/div&gt;
  </code></pre>
  
  <p>I'm trying to toggle the background color of <code>div</code> whenever checkbox is checked or unchecked, which is not working.</p>
  
  <p>Here is the <a href="http://codepen.io/anon/pen/vNeMML" rel="nofollow">complete code</a></p>
  
  <p>However, implementing same code without toggle logic is working fine - <a href="http://codepen.io/anon/pen/NGamma" rel="nofollow">link</a></p>
  
  <p>Kindly suggest what could be going wrong. </p>