body{width:100%;height:100%;margin:0;padding:0;background-color:gray}canvas{width:100%;height:100vh}.loading{border:5px solid #f3f3f3;border-top:5px solid #3498db;border-radius:50%;width:50px;height:50px;animation:spin 1s linear infinite}@keyframes spin{0%{transform:rotate(0)}to{transform:rotate(360deg)}}