title: how to disable all div contents using a trasparent div?
body: <p>I have a 3-columns template in my web application.</p>
  
  <p>Imagine that the right-side div is <code>&lt;div id="right"&gt;</code> In some pages I want to disable all contents in this div using another div that has a transparent background.</p>
  
  <p>How can I do it?</p>
  
  <p>(please tell me your suggestions with a click on <code>&lt;input type="button" id="btn" value="Disable" /&gt;</code> as a handler)</p>