title: Active and Inactive div
body: <p>I want to trigger functions when a certain div is no longer displayed. I have tons of divs which acts like Tabs but they aren't.
  Any way to add a certain event listener on changing a div?
  displaying and hiding divs using css.
  I need something like :</p>
  
  <pre><code>div.active : //do stuff
  div:inactive :  //do stuff
  </code></pre>
  
  <p><strong>Edit:</strong>
  need some event listener to listen to change of visible and invisible of the div</p>