CodePen

HTML

            
              <iframe src="http://www.css-tricks.com"></iframe>

<div id="front">FRONT</div>
            
          
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via HTML Inspector

CSS

            
              
iframe {
  width:200px;
  height:200px;
  position:absolute;
  border:solid 1px #000;
}


#front {
  position:absolute;
  border:solid 1px #000;
  width:100px;
  height:100px;
  left:120px;
  top:120px;
  background:#f00;
  box-shadow:0 0 10px #666;
  
}
  
  
            
          
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JS

            
              
            
          
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