title: Why is the flap opening then closing before opening?
body: <p>I am trying to use this CodePen (see below) which is an envelope effect.</p>
  
  <p>The top flap  should open when button is clicked, then when the form is sent the top flap should close. </p>
  
  <p>However the issue is: When opening/closing it does a double take. The top flap will open then fold behind the envelope before coming back to the "open" state. The reverse happens when it closes. </p>
  
  <p>How do I remove that open->close->open effect?</p>
  
  <p>Here is the codepen I'm using.</p>
  
  <p><a href="http://codepen.io/permanentinc/pen/muFxK" rel="nofollow">http://codepen.io/permanentinc/pen/muFxK</a></p>
  
  <p>I believe the culprit is the following piece of code:</p>
  
  <pre><code>.close_sesame {
   transform: rotatex(180deg);
   z-index: 9999 ;
  }
  </code></pre>