#back-to-top-btn{position:fixed;bottom:30px;right:30px;width:50px;height:50px;border-radius:50%;background-color:#0d6efdcc;color:#fff;border:none;cursor:pointer;z-index:9999;display:flex;align-items:center;justify-content:center;font-size:20px;box-shadow:0 4px 12px #00000026;transition:all .3s cubic-bezier(.25,.8,.25,1)}#back-to-top-btn:hover{background-color:#0d6efd;transform:translateY(-5px);box-shadow:0 7px 15px #00000040}#back-to-top-btn:focus{outline:none;box-shadow:0 0 0 3px #0d6efd80,0 4px 12px #00000026}#back-to-top-btn:active{transform:translateY(-2px)}#back-to-top-btn.hidden{opacity:0;visibility:hidden;transform:translateY(20px) scale(.9);pointer-events:none}#back-to-top-btn.visible{opacity:1;visibility:visible;transform:translateY(0) scale(1);pointer-events:auto}#back-to-top-btn i{transition:transform .2s ease}#back-to-top-btn:hover i{transform:translateY(-3px)}@media (max-width: 768px){#back-to-top-btn{width:45px;height:45px;font-size:18px;bottom:20px;right:20px}}@media (max-width: 480px){#back-to-top-btn{width:40px;height:40px;font-size:16px;bottom:15px;right:15px}}@media (prefers-color-scheme: dark){#back-to-top-btn{background-color:#0d6efdb3;box-shadow:0 4px 12px #0000004d}#back-to-top-btn:hover{background-color:#0d6efde6}}