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HTML

              
                <div class="bg"></div>

<div class="star-field">
<div class="layer"></div>
<div class="layer"></div>
<div class="layer"></div>
              
            
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CSS

              
                .bg{background:url(https://1.bp.blogspot.com/-DC008lu58Nc/W1LMf54UKXI/AAAAAAAAACQ/REydlqiHDecasKOrG7qdP1Z5GQdlRDdxgCLcBGAs/s1600/galaxy-blue.jpg) no-repeat;background-size:cover;height:100%;width:100%;position:fixed;top:0;left:0;z-index:-3}.bg:before{content:'';width:100%;height:100%;background:#000;position:fixed;z-index:-1;top:0;left:0;opacity:.3}@keyframes sf-fly-by-1{from{transform:translateZ(-600px);opacity:.5}to{transform:translateZ(0);opacity:.5}}@keyframes sf-fly-by-2{from{transform:translateZ(-1200px);opacity:.5}to{transform:translateZ(-600px);opacity:.5}}@keyframes sf-fly-by-3{from{transform:translateZ(-1800px);opacity:.5}to{transform:translateZ(-1200px);opacity:.5}}.star-field{position:fixed;top:0;left:0;width:100%;height:100%;perspective:600px;-webkit-perspective:600px;z-index:-1}.star-field .layer{box-shadow:-411px -476px #cccccc,777px -407px #d4d4d4,-387px -477px #fcfcfc,-91px -235px #d4d4d4,491px -460px #f7f7f7,892px -128px #f7f7f7,758px -277px #ededed,596px 378px #cccccc,647px 423px whitesmoke,183px 389px #c7c7c7,524px -237px #f0f0f0,679px -535px #e3e3e3,158px 399px #ededed,157px 249px #ededed,81px -450px #ebebeb,719px -360px #c2c2c2,-499px 473px #e8e8e8,-158px -349px #d4d4d4,870px -134px #cfcfcf,446px 404px #c2c2c2,440px 490px #d4d4d4,414px 507px #e6e6e6,-12px 246px #fcfcfc,-384px 369px #e3e3e3,641px -413px #fcfcfc,822px 516px #dbdbdb,449px 132px #c2c2c2,727px 146px #f7f7f7,-315px -488px #e6e6e6,952px -70px #e3e3e3,-869px -29px #dbdbdb,502px 80px #dedede,764px 342px #e0e0e0,-150px -380px #dbdbdb,654px -426px #e3e3e3,-325px -263px #c2c2c2,755px -447px #c7c7c7,729px -177px #c2c2c2,-682px -391px #e6e6e6,554px -176px #ededed,-85px -428px #d9d9d9,714px 55px #e8e8e8,359px -285px #cfcfcf,-362px -508px #dedede,468px -265px #fcfcfc,74px -500px #c7c7c7,-514px 383px #dbdbdb,730px -92px #cfcfcf,-112px 287px #c9c9c9,-853px 79px #d6d6d6,828px 475px #d6d6d6,-681px 13px #fafafa,-176px 209px #f0f0f0,758px 457px #fafafa,-383px -454px #ededed,813px 179px #d1d1d1,608px 98px whitesmoke,-860px -65px #c4c4c4,-572px 272px #f7f7f7,459px 533px #fcfcfc,624px -481px #e6e6e6,790px 477px #dedede,731px -403px #ededed,70px -534px #cccccc,-23px 510px #cfcfcf,-652px -237px whitesmoke,-690px 367px #d1d1d1,810px 536px #d1d1d1,774px 293px #c9c9c9,-362px 97px #c2c2c2,563px 47px #dedede,313px 475px #e0e0e0,839px -491px #e3e3e3,-217px 377px #d4d4d4,-581px 239px #c2c2c2,-857px 72px #cccccc,-23px 340px #dedede,-837px 246px white,170px -502px #cfcfcf,822px -443px #e0e0e0,795px 497px #e0e0e0,-814px -337px #cfcfcf,206px -339px #f2f2f2,-779px 108px #e6e6e6,808px 2px #d4d4d4,665px 41px #d4d4d4,-564px 64px #cccccc,-380px 74px #cfcfcf,-369px -60px #f7f7f7,47px -495px #e3e3e3,-383px 368px #f7f7f7,419px 288px #d1d1d1,-598px -50px #c2c2c2,-833px 187px #c4c4c4,378px 325px whitesmoke,-703px 375px #d6d6d6,392px 520px #d9d9d9,-492px -60px #c4c4c4,759px 288px #ebebeb,98px -412px #c4c4c4,-911px -277px #c9c9c9;transform-style:preserve-3d;position:absolute;top:50%;left:50%;height:4px;width:4px;border-radius:2px}.star-field .layer:nth-child(1){animation:sf-fly-by-1 5s linear infinite}.star-field .layer:nth-child(2){animation:sf-fly-by-2 5s linear infinite}.star-field .layer:nth-child(3){animation:sf-fly-by-3 5s linear infinite}
              
            
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JS

              
                
              
            
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999px

Console