#side_catalog_nav{position:fixed;bottom:72px;left:0;display:none}#side_catalog_nav ul{list-style:none}#side_catalog_nav li{width:50px;height:48;text-align:center;line-height:18px;color:#fff;padding:10px 10px;margin-bottom:1px;background:skyblue;border-radius:2px;cursor:pointer}#side_catalog_nav li.current{background:tomato}@media(max-width:991px){#side_catalog_nav li{opacity:.85}}#to_top{right:30px;bottom:30px;position:fixed;opacity:.85;cursor:pointer;display:none;z-index:50}@media(max-width:991px){#to_top{right:4px;bottom:4px}}