.stars{z-index:-1;background:#000;width:100%;height:100%;position:fixed;top:0;left:0;overflow:hidden}.stars:after{content:"";background:radial-gradient(2px 2px at 20px 30px,#fff,#0000),radial-gradient(1.5px 1.5px at 120px 80px,#fff,#0000),radial-gradient(2px 2px at 200px 200px,#fff,#0000),radial-gradient(1.2px 1.2px at 300px 50px,#fff,#0000),radial-gradient(1.3px 1.3px at 600px 400px,#fff,#0000);width:200%;height:200%;animation:30s linear infinite moveStars;position:absolute;top:-100%}@keyframes moveStars{0%{transform:translateY(0)}to{transform:translateY(100%)}}