html,body { overflow-y: auto; }
#top { position: fixed; top: 0; left: 0; } 
#bot { position: fixed; bottom: 0; left: 0; } 
div.thumbs { display: block; margin: 45px 132px 55px; text-align: center; }
div.thumbs ul { display: block; margin: 0 auto; list-style-image: none; list-style-type: none; padding: 0; margin: 0; }
div.thumbs ul li { display: block; float: left; margin: 10px 15px 0 0; }
div.thumbs ul li a img { opacity: 0.80; filter: alpha(opacity=80); }
div.thumbs ul li a:hover img { opacity: 1; filter: alpha(opacity=100); }