Using JS to set CSS variables

HTML

<div>
  The colors will change after 2 seconds
</div>

CSS

:root {
  --white: #fff;
  --black: limegreen;
}

body {
  background-color: var(--white);
  color: var(--black);
}

JavaScript

setTimeout( () => {
  document.documentElement.style.setProperty('--black', 'hotpink');
  document.documentElement.style.setProperty('--white', '#000');
}, 2000)

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Using JS to set CSS variables

HTML

CSS

JavaScript

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Join the 4+ million users, and keep the JSFiddle dream alive.

Ad-free

Use pre-released features

Fiddle collections

Private collections and fiddles

Console