html{scroll-behavior:smooth;}body{margin:0;padding:0;}section{width:100%;height:300vh;background:url(bg.jpg) no-repeat;background-size:cover;}.fa-arrow-alt-circle-up{background:#27ae60;border-radius:50%;height:1em;width:1em;}.gotopbtn{position:fixed;bottom:20px;right:10px;text-decoration:none;text-align:center;line-height:20px;color:white;font-size:22px;}