html, body {
	margin: 0px;
	padding: 0px;
}
.imgBox {
	position: absolute;
	text-align: center;
	width: 100%;
	height: -webkit-calc(100% - 4px);
}
.imgBox img {
	position: relative;
	width: auto;
	height: auto;
	max-width: 100%;
	max-height: 100%;	
}