.back-to-top{align-items:center;bottom:30px;cursor:pointer;display:flex;justify-content:center;opacity:.75;position:fixed;right:-150px;transition:right .3s ease,background-color .2s ease,transform .2s ease;z-index:9999}.back-to-top.is-visible{right:20px}.back-to-top:hover{opacity:.9;transform:translateY(-3px)}