ul#flickrMosaic { float: left; display: block; clear: both; } ul#flickrMosaic li { position: relative; width: 66px; height: 57px; float: left; display: inline; list-style: none; padding: 0px !important; margin: 0px !important; overflow: hidden; line-height: 0px; background-color: black; } ul#flickrMosaic li:hover { opacity: 0.8; filter: alpha(opacity = 80); } ul#flickrMosaic img { position: absolute; top: 0px; left: 0px; width: 80px; z-index: 1; }