.back-to-top{position:fixed;right:20px;bottom:20px;z-index:40;font-size:1.5rem;opacity:0;visibility:hidden;transition:opacity .2s ease,visibility .2s ease,transform .1s ease}.back-to-top:hover{transform:translateY(-1px)}.back-to-top.show{opacity:1;visibility:visible}@media(max-width:768px){.back-to-top{right:12px;bottom:12px}}