ul.thumb {float: left;list-style: none;margin: 0; padding: 0;width: 645px;}
ul.thumb li {margin: 0; padding: 2px;float: left;position: relative;width: 61px;height: 53px;}
ul.thumb li img {width: 61px;height: 53px;padding: 2px;position: absolute;left: 0; top: 0;-ms-interpolation-mode: bicubic; }
ul.thumb li img.hover {margin-top:15px;background:url(thumb_bg.png) no-repeat center center;border: none;}