.thumb{
    width:170px;
	height: auto; 
    position:relative;
	overflow: hidden;
 }
 .alt{    
    position:absolute; 
	top:0; 
	left:-100%;
	width:170px;
	height:100%;
	background:rgba(0, 0, 0, 0.4);
	line-height:25px;
	color:#fff;
	padding-left:5px;
 }