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CSS Base

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Babel includes JSX processing.

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Editor Settings

Code Indentation

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                <p>Scroll down.</p>
<h1>Rainbows are cool at any time.</h1>


                h1 {
    display: inline; // needs a block wrapper if not surrounded by block elements
    //background-image: url(;
				#5461c8 0 12.5%, 
				#c724b1 0 25%, 
				#e4002b 0 37.5%, 
				#ff6900 0 50%, 
				#f6be00 0 62.5%, 
				#97d700 0 75%, 
				#00ab84 0 87.5%, 
				#00a3e0 0 100%);

    background-repeat: repeat-x;
    background-size: 100% 0.2em;
    background-position: left bottom 8px;
    background-position-x: var(--scrollPos);

// defaults

* {
  box-sizing: border-box;

body {
  font: 900 40px system-ui, -apple-system, sans-serif;
  margin: 1rem;
  min-height: 200vh;

p {
  margin-bottom: 8rem;


                window.addEventListener("scroll", e => {
  // Dealing with Safari difference.
  // look into scrollingElement
  let scrollTop = document.body.scrollTop ? document.body.scrollTop : document.documentElement.scrollTop; 
  let newPos = scrollTop + "px";'--scrollPos', newPos);