.erd{
		width: 1200px;
		height: 160px;
		position: absolute;
		left: 0px;
		transition: left 1s;
		-moz-transition: left 1s;	/* firefox 4 */
		-webkit-transition: left 1s;	/* safari 和 chrome */
		-o-transition: left 1s;}
	.erd li{
		float: left;
		padding-left: 5px;
		padding-right: 5px;}
	.widows{
		width: 100%;
		height: 160px;
		overflow: hidden;
		position: relative;}
	#prvs{
		z-index: 10;
		position: absolute;
		top: 50px;
		right:0px;
		font-size: 50px;
		color: #fff;
		opacity:0.2;
		filter:Alpha(opacity=20);}
	#nexts{
		
		z-index: 10;
		position: absolute;
		top: 50px;
		left:0px;
		font-size: 50px;
		color: #fff;
		opacity:0.2;
		filter:Alpha(opacity=20);}	
	#nexts:hover{
		display: block;
		background-color: #000;
		opacity:0.5;
		filter:Alpha(opacity=50); /* ie8 以及更早的浏览器 */
		cursor: pointer;}
	#prvs:hover{
		display: block;
		background-color: #000;
		opacity:0.5;
		filter:Alpha(opacity=50); /* ie8 以及更早的浏览器 */
		cursor: pointer;}
	li{
		list-style: none;}