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<p>Change the hue!</p>

<input type='range' min='0' max='1000'>



html {
  --hue: 150; /* change me! */

body {
	background-color: hsl(var(--hue), 100%, 50%);

body {
	padding: 30px;


var html = document.querySelector('html');
var colorPicker = document.querySelector('input');

function updateHue(input) {
	console.log(input);'--hue', this.value);
	// 'this' refers to the input in this case

colorPicker.addEventListener('input', updateHue);

/* just to show some color contrast */
var dark = document.createElement('div');
dark.classList.add('circle'); = '100px'; = '100px'; = 'rgba(0,0,0,.3)'; = "50%"; = "fixed"; = "100px"; = 'none'; = "40px";

var light = document.createElement('div');
light.classList.add('circle'); = '200px'; = '200px'; = 'rgba(255,255,255,.5)'; = "50%"; = "fixed"; = "-20px"; = "100px"; = 'none';

// 100% serious ^ this is the most document.createElement type code I've written in my entire career... in one sitting...  - @sheriffderek
// this is not likely to be how you create DOM