#slide{
	height: 200px; 
	width: 200px; 
	clear: both;
}

#box1, #box2{
	position:absolute;
}

.mask{
	position:relative;
	width:200px;
	height:200px;
	overflow:hidden;
}
.mask img{
	position:absolute;
	display:block;
	border:none;
}