#button-top{border-radius:4px;bottom:30px;display:inline-block;height:50px;opacity:0;position:fixed;right:30px;text-align:center;transition:background-color .3s,opacity .5s,visibility .5s;visibility:hidden;width:50px;z-index:1000}#button-top:after{border:solid #fff;border-width:0 3px 3px 0;content:"";display:inline-block;margin-top:20px;padding:8px;transform:rotate(-135deg);-webkit-transform:rotate(-135deg)}#button-top:hover{cursor:pointer;opacity:.7}#button-top.show{opacity:1;visibility:visible}