body{background-color:#000;background-image:radial-gradient(#fff,hsla(0,0%,100%,.2) 2px,transparent 40px),radial-gradient(#fff,hsla(0,0%,100%,.15) 1px,transparent 30px),radial-gradient(#fff,hsla(0,0%,100%,.1) 2px,transparent 40px),radial-gradient(hsla(0,0%,100%,.4),hsla(0,0%,100%,.1) 2px,transparent 30px);background-size:550px 550px,350px 350px,250px 250px,150px 150px;background-position:0 0,40px 60px,130px 270px,70px 100px;animation:backgroundAnimation 50s linear infinite}@keyframes backgroundAnimation{0%{background-position:0 0,40px 60px,130px 270px,70px 100px}to{background-position:550px 550px,390px 410px,380px 520px,220px 250px}}