body{
	margin:0;
	padding:0;
}
.box{
	position: absolute;
	left: 0;
	top: 0;
	bottom: 0;
	right: 0;
	background: url("../images/1.jpg") no-repeat;
	background-size: 100% 100%;
	backface-visibility: hidden;
	overflow: hidden;
    width:1200px;
	height: 675px;

}
#cas{
	width: 100%;
	height: 100%;
	opacity: 1;
	-webkit-transition:opacity .5s;
	-ms-transition:opacity .5s;
	-moz-transition:opacity .5s;
}

.noOp{
	opacity: 0 !important;
}