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HTML

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

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JavaScript

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JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML 

              
                <div class="box">
  <div>
    <div>
      <div>
        <div>
          <div>
            <div>
              <div>
                <div>
                  <div>
                  </div>
                </div>
              </div>
            </div>
          </div>
        </div>

      </div>
    </div>
  </div>
</div>
!

CSS 

              
                .box {
  width:100vmin;
  height:100vmin;
  display:flex;
  margin:auto;
  position:relative;
}
.box::before,
.box div::before{
   content:"";
   position:absolute;
  border-radius:50%;
  inset:0; 
  background:
     conic-gradient(from 30deg,hsl(30, 100%, 40%) 30deg,#0000 30.1deg),
     conic-gradient(from 60deg,hsl(60, 100%, 40%) 30deg,#0000 30.1deg),
     conic-gradient(from 90deg,hsl(90, 100%, 40%) 30deg,#0000 30.1deg),
     conic-gradient(from 120deg,hsl(120, 100%, 40%) 30deg,#0000 30.1deg),
     conic-gradient(from 150deg,hsl(150, 100%, 40%) 30deg,#0000 30.1deg),
     conic-gradient(from 180deg,hsl(180, 100%, 40%) 30deg,#0000 30.1deg),
     conic-gradient(from 210deg,hsl(210, 100%, 40%) 30deg,#0000 30.1deg),
     conic-gradient(from 240deg,hsl(240, 100%, 40%) 30deg,#0000 30.1deg),
     conic-gradient(from 270deg,hsl(270, 100%, 40%) 30deg,#0000 30.1deg),
     conic-gradient(from 300deg,hsl(300, 100%, 40%) 30deg,#0000 30.1deg),
     conic-gradient(from 330deg,hsl(330, 100%, 40%) 30deg,#0000 30.1deg),
     conic-gradient(from 360deg,hsl(360, 100%, 40%) 30deg,#0000 30.1deg);
  -webkit-mask:radial-gradient(farthest-side,#0000 calc(100% - 5vmin - 1px),#000 calc(100% - 5vmin) )
 }
 
.box  div {
   background:inherit;
   position:relative;
   flex-grow:1;
   border-radius:inherit;
   display:inherit;
   opacity:0.9;
   margin:5vmin;
   animation: r 10s linear infinite;
}

@keyframes r {
  to {
    transform:rotate(360deg);
  }
}
!

JS
!
999px

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