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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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CSS

About CSS Preprocessors

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

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

We offer two popular choices: Autoprefixer (which processes your CSS server-side) and -prefix-free (which applies prefixes via a script, client-side).

Add External Stylesheets/Pens

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JavaScript

About JavaScript Preprocessors

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

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Babel includes JSX processing.

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If the script you link to has the file extension of a preprocessor, we'll attempt to process it before applying.

You can also link to another Pen here, and we'll pull the JavaScript from that Pen and include it. If it's using a matching preprocessor, we'll combine the code before preprocessing, so you can use the linked Pen as a true dependency.

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Packages

Add Packages

Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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About Packages

Using packages here is powered by esm.sh, which makes packages from npm not only available on a CDN, but prepares them for native JavaScript ESM usage.

All packages are different, so refer to their docs for how they work.

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HTML 

              
                - let t = 12;
.nucl(style=`--t:${t}`)
  .cont
    -for(let i=1; i<=t;i++)
      .ele(style=`--r:${i};`)
        .dot 
          .fill
//expansion of
//https://codepen.io/ghaste/pen/MWxMgWK
!

CSS 

              
                @mixin sizingEle {
    width: 50vmin;
    height: 50vmin;
    top: 0;
    left: 0;
    border-radius: 100%;
    border: 1px dashed color-mix(in lab, var(--clr), #0003 30%);
    position: absolute;
    //translate: -20vmin -20vmin;
    z-index: 1;
}
@mixin sizing {
  position: absolute;
    width: 3vmin;
    height: 3vmin;
    top: 0;
    left: 0;
    background-color: var(--clr);
    border-radius: 100%;
}
@mixin pseudo-fill() {
  &::before,
  &::after {
    content: "";
    @include sizing;
    transform: rotatex(90deg);
  }
  &::after {
    transform: rotatey(90deg);
  }
}
:root {
  --bg: #fbf7f4;
  --clr: #aee1cd;
}
div {
  box-sizing: border-box;
  transform-style: preserve-3d;
}
body {
  display: grid;
  place-content: center;
  margin: 0;
  min-height: 100vh;
  background-color: var(--bg);
  perspective: 50vmin;
}

.nucl {
  position: relative;
  width: 10vmin;
  height: 10vmin;
  //border: 1px solid;
  background: radial-gradient(circle, #3cf 50%, #0000 0) 50% 50% / 60% 60% space,
    radial-gradient(circle, #3fc 50%, #0000 0) 50% 15% / 60% 40% space,
    radial-gradient(circle, #f9c 50%, #0000 0) 50% 50% / 50% 90% space,
    radial-gradient(circle, #3cf 50%, #0000 0) 0 0 / 45% 45% space;
  .cont {
    position: relative;
    width: 50vmin;
    height: 50vmin;
    translate: -20vmin -20vmin;
    animation: turn 60s linear infinite forwards;
    //border: 1px solid;
  }

  .ele {
    @include sizingEle;
    
    transform: rotatez(calc(var(--r) * 180deg / var(--t)))
      rotatex(calc(var(--r) * 180deg / var(--t)))
      rotatey(calc(var(--r) * 180deg / var(--t)));
    .dot {
      //border: 1vmin solid var(--bg);
      @include sizing;
      offset-path: border-box;
      offset-distance: 0%;
      offset-rotate: 90deg;
      animation: rot linear 4s infinite forwards calc(var(--r) * -1s);
      z-index: 5;
      @include pseudo-fill;
      .fill {
        @include sizing;
        background-color: var(--clr);
        border-radius: 100%;
        transform: rotatex(45deg) rotatey(45deg);

        @include pseudo-fill;
      }
    }
  }
}
.nucl:hover .ele {
  border-color: color-mix(in lab, var(--clr), #000 50%);
}
@keyframes turn {
  to {
    transform: rotatex(360deg) rotatey(360deg) rotatez(360deg);
  }
}
@keyframes rot {
  to {
    offset-distance: 100%;
  }
}
!

JS
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999px

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