body {
	background-color: #222222;
}


.child {
 display: block;
 position: absolute;
 top: 50%;
 left: 50%;
 transform: translate(-50%, -50%);
 -webkit-transform: translate(-50%, -50%); /* Safari and Chrome */
 -moz-transform: translate(-50%, -50%); /* Firefox */
 -ms-transform: translate(-50%, -50%); /* IE 9 */
 -o-transform: translate(-50%, -50%); /* Opera */
 // I suppose you may like those too:
  max-width: 80%;
 max-height: 80%;
}