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Use npm Packages

We can make npm packages available for you to use in your JavaScript. We use webpack to prepare them and make them available to import. We'll also process your JavaScript with Babel.

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HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <div class="container">
	<div class="bubble"></div>
	<div class="bubble"></div>
	<div class="bubble"></div>
	<div class="bubble"></div>
	<div class="bubble"></div>

	<p class="intructions">Move the cursor / touch around to bring some color!</p>
              /* breath behaves based on the
CSS variables values that are inherited */
@keyframes breath {
	0% {
		background: var(--colorStart);
		transform: scale(var(--scaleStart));
	100% {
		background: var(--colorEnd);
		transform: scale(var(--scaleEnd));

.container {
	background: black;
	/* all "breath" animations inside */
	/* will start grey... */
	--colorStart: #222;
	/* and end white'ish (until you start to move the cursor around) */
	--colorEnd: #eee;
	color: var(--colorEnd);

.bubble {
	/* each bubble starts with these common specs: */
	--scaleStart: 0.3;
	background: var(--colorStart);
	transform: scale(var(--scaleStart));
	animation: breath 2s alternate infinite ease-in-out;

/* customize each bubble specs... */

.bubble:nth-child(5) {
	--scaleEnd: 1;

.bubble:nth-child(4) {
	--scaleEnd: 1.2;
	animation-delay: -250ms;

.bubble:nth-child(3) {
	--scaleEnd: 1.6;
	animation-delay: -500ms;

/* styles not related to the animation */

.container {
	display: flex;
	align-items: center;
	justify-content: center;
	min-height: 100vh;
	max-width: 100vw;

.bubble {
	margin: 1rem;
	width: 2.5rem;
	height: 2.5rem;
	border-radius: 50%;

.intructions {
	position: absolute;
	width: 100%;
	top: 0; left: 0;
	padding-top: 2rem;
	font-family: sans-serif;
	font-weight: 600;
	text-align: center;

              /* Bonus: Use JS to improve even more CSS @keyframes
Here we just use it to update the color */

const doc = document.documentElement;
const container = document.getElementsByClassName('container')[0];

doc.addEventListener("touchmove", updateBubbleColors);
doc.addEventListener("mousemove", updateBubbleColors);

function updateBubbleColors(e) {
  const w = window.innerWidth / 255;
  const h = window.innerHeight / 255;
  const x = parseInt(e.pageX / w, 10);
  const y = parseInt(e.pageY / h, 10);

  const r = x;
  const g = (y - 255) * -1;
  const b = x <= y ? y - x : 0;'--colorEnd', `rgb(${r},${g},${b})`);

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