.btn-top{position:fixed;right:0;bottom:0;width:90px;height:90px;background:transparent url(/static/img/quick_top.png) no-repeat center;-webkit-background-size:cover;background-size:cover;z-index:100;outline:none;border:none;opacity:0;visibility:hidden;transition:visibility 0.3s ease-in-out,opacity 0.3s ease-in-out;cursor:pointer}.btn-top.show{opacity:1;visibility:visible}.btn-top:focus,.btn-top:active{outline:none}input[type="image"]{outline:none}