.back-to-top{position:fixed;right:24px;bottom:24px;z-index:9999;border:1px solid rgba(20,20,17,.25);background:#171915;color:#fff;padding:13px 17px;border-radius:999px;font:700 12px/1 Arial,sans-serif;letter-spacing:.03em;cursor:pointer;box-shadow:0 8px 30px rgba(0,0,0,.16);opacity:0;transform:translateY(12px);pointer-events:none;transition:.2s ease}.back-to-top.visible{opacity:1;transform:none;pointer-events:auto}.back-to-top:hover{transform:translateY(-2px)}.back-to-top span{margin-left:5px}@media(max-width:640px){.back-to-top{right:14px;bottom:14px;padding:13px}.back-to-top span{display:none}}