.scroll-up-button{position:fixed;left:10px;background:#4f4f4f none repeat scroll 0 0;border-radius:5px;color:#fff;cursor:pointer;font:30px/30px sans-serif;height:auto;margin-bottom:5px;opacity:.5;padding:3px 0;text-align:center;text-shadow:0 1px 2px #000;width:24px;z-index:100}.scroll-up-button.scroll_top{bottom:100px}.scroll-up-button.scroll_bottom{bottom:60px}.scroll-up-button:hover{opacity:1}