:root { } html { height:100vh; width:100vw; background: linear-gradient(45deg, gold 2%, purple); overflow: hidden; margin:0px; animation: gradient 35s linear infinite; background-size: 180% 180%; } body { display flex; color: white; margin: 0px; } .artical{ width: min(100vw, 55em); margin:auto; text-align: center; padding: 0px; } .artical h1 { margin: auto auto 0px auto; } .artical hr { background: white; border-color: white; border-radius: 3em; height: 0.3em; } .glass{ background: rgba(128, 128, 128, 0.35); box-shadow: 0 4px 30px rgba(0, 0, 0, 0.1); border-radius: 3em; padding: 1em 2em; } @keyframes gradient { 0% { background-position: 0% 50%; } 50% { background-position: 100% 50%; } 100% { background-position: 0% 50%; } }