#loading{position:absolute;z-index:1000;background-color:#fff;height:100vh;width:100vw;text-align:center;line-height:1vh}.img{position:relative;margin:auto;margin-top:1%}#scrollToTopBtn{background-color:#000;border:none;border-radius:50%;color:#fff;cursor:pointer;font-size:25px;line-height:48px;width:48px}