/* Sample 1*/
#box1{
	position:absolute;
}
#box1 span{
	display:block;
	float:left;
}



.mask1{
	position:relative;
	width:320px;
	height:240px;
	overflow:hidden;
}
.mask2{
	position:relative;
	width:240px;
	height:180px;
	overflow:hidden;
}
.mask3{
	position:relative;
	width:480px;
	height:240px;
	overflow:hidden;
}

span img{
	display:block;
	border:none;
}