.back-to-top{position:fixed;bottom:5px;right:11px;width:auto;font-size:20px;padding:1px 8px 4px;border-radius:4px;background:#34495e;cursor:pointer}.hovertext{border-bottom:1px dotted black}.hovertext:before{content:attr(data-hover);visibility:hidden;opacity:0;width:140px;background-color:black;color:#fff;text-align:center;border-radius:5px;padding:5px 0;transition:opacity 1s ease-in-out;position:absolute;z-index:1;right:0px;top:-120%}.hovertext:hover:before{opacity:1;visibility:visible;