.thumbnail{ position: relative; z-index: 0; }
.thumbnail:hover{ background-color: transparent; z-index: 50; }
.thumbnail span{ position: absolute; background-color: lightyellow; padding: 5px; left: -1000px; border: 1px dashed gray;
					visibility: hidden; color: black; text-decoration: none; }
.thumbnail span img{ border-width: 0; padding: 2px; }
.thumbnail:hover span{ visibility: visible; top: 0; left: 60px; }