title: Allow a div to cover the whole page instead of the area within the container
body: <p>I'm trying to make a semi-transparent div cover the whole screen. I tried this:</p>
  
  <pre><code>#dimScreen
  {
      width: 100%;
      height: 100%;
      background:rgba(255,255,255,0.5);
  }
  </code></pre>
  
  <p>But that doesn't cover the whole screen, it only covers the area within the div.</p>