title: What's the best way to layer divs on top of one another in z-index?
body: <p>I want to have some divs stacked on top of one another, but act otherwise like a normal div. I.e. I don't want to have to worry about manually positioning them. Is this possible in HTML5/CSS3?</p>
  
  <p>For example:</p>
  
  <pre><code>&lt;div id='outerDiv'&gt;
      &lt;div id='inner1' style='z-index: 1'&gt;This should be the full size of outerDiv&lt;/div&gt;
      &lt;div id='inner2' style='z-index: 2'&gt;This should appear overtop of inner1&lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>I hope there's a simple way to do this.</p>
  
  <p>To put it another way, suppose I already have a page laid-out and perfect, but I want to take one already-positioned div and super-impose another div directly on top of it, exactly the same size, without screwing the existing layout up. Is this possible?</p>