<div id="quad">
  <figure>
  <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/4273/rose-red-wine.jpg" alt="rose-red-wine">
  <figcaption>Rose Red Wine</figcaption>
  </figure>
  <figure>
    <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/4273/green-glass-bottle.jpg" alt>
    <figcaption>Green Glass Bottle</figcaption>
  </figure>
  <figure>
    <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/4273/guinness-barrels.jpg" alt>
    <figcaption>Guinness Barrels, Dublin</figcaption>
  </figure>
  <figure>
    <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/4273/crystal-skull-vodka.jpg" alt>
    <figcaption>Crystal Skull Vodka</figcaption>
  </figure>
</div>

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}
div#quad { 
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  margin: 0 auto;
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}
div#quad figure { 
  margin: 0; width: 50%; 
  height: auto; transition: 1s; 
  display: inline-block; 
  position: relative; overflow: hidden; 
}
div#quad figure:hover { cursor: pointer; z-index: 4; }
div#quad figure img { width: 100%; height: auto; }
div#quad figure:nth-child(1) { transform-origin: top left; }
div#quad figure:nth-child(2) { transform-origin: top right; }
div#quad figure:nth-child(3) { transform-origin: bottom left; }
div#quad figure:nth-child(4) { transform-origin: bottom right; }
div#quad figure figcaption { 
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  color: #fff; padding: .3rem; 
  font-size: 1.2rem; 
  position: absolute; 
  bottom: 0; width: 100%;
	transition: 1s 1s opacity; 
}
.expanded { transform: scale(2); z-index: 5;  }
div#quad figure.expanded figcaption { opacity: 1; }
div.full figure:not(.expanded) { pointer-events: none; }

var quadimages = document.querySelectorAll("#quad figure");
for(i=0; i<quadimages.length; i++) {
  quadimages[i].addEventListener('click', function(){ this.classList.toggle("expanded"); quad.classList.toggle("full") }); 
}