#ns_basetheme_back_to_top{z-index:9999;text-align:center;color:#444;cursor:pointer;opacity:0;background:#f5f5f5;border:0;border-radius:2px;width:32px;height:32px;line-height:30px;text-decoration:none;transition:opacity .2s ease-out;position:fixed;bottom:40px;right:40px}#ns_basetheme_back_to_top:hover{background:#e9ebec}#ns_basetheme_back_to_top.show{opacity:1}#content{height:2000px}