CodePen Embed - CSS - Centering Trick

<div>
</div>

div {
  width: 200px;
  height: 200px;
  background: gold;
  margin: auto;
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
}

This Pen is owned by sundicide on CodePen.

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