* {
    margin:0;padding:0;
}

ul {
    width:100%; 
    height:100%; 
    max-height:100%;
    max-width:100%; 
    margin:auto auto;
    position:absolute;
    top:0;bottom:0; 
    left:0;right:0; 
	overflow-x:hidden;
	list-style:none;
}

li{
	float:left;
	width:25%;
	z-index:10;
}

li img {
    min-width:100%;
    vertical-align:middle;
	/* display:block; */
	z-index:20;
}