* {
	margin:0;
	padding:0;
	list-style:none;
}
#box {
	width:700px;
	height:400px;
	margin:20px auto;
	position:relative;
	perspective:800px;
}
#box span {
	position:absolute;
	background:url(http://www.jq22.com/img/cs/500x300-1.png) no-repeat;
	transform-style:preserve-3d;
	transition:1s all ease;
	transform-origin:top center;
}
#box span em {
	position:absolute;
	width:100%;
	height:100%;
}
#box span em.front {
	background:url(http://www.jq22.com/img/cs/500x300-1.png) no-repeat;
	transform:translateZ(0.1px);
}
#box span em.back {
	background:url(http://www.jq22.com/img/cs/500x300-2.png) no-repeat;
	transform:translateZ(-0.1px) scale(-1,1);
}