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                <link href=',400,700' rel='stylesheet' type='text/css'>
<h1>CustomWiggle Swarm <span style="font-weight:300">(using type:"random")</span></h1>

<div class="ball"></div>

<p>Each dot has only one tween for "x" and one for "y", infinitely repeating.</p>



                body {
  background-color: black;
  font-family: Signika Negative, Asap, sans-serif;
  color: #ccc;
  font-weight: 300;
  font-size: 1.3em;
  padding: 20px;
  text-align: center;

.ball {
  width: 20px;
  height: 20px; 
  margin-top: 180px;
  border-radius: 50%;
  background-color: #90E500;
  display: inline-block;
  position: absolute;
h1, strong {
  color: white;
  font-weight: 400;
  line-height: 1.3em;
a:link, a:visited {
  text-decoration: none;
a:hover {
  text-decoration: underline;


                //copies the ball 20 times	
copy(".ball", 20);

//swarms all the balls by 400px in each direction on the x-axis, 150 on the y-axis, and uses a 12-second duration for each tween and 15 wiggles.
swarm(".ball", 400, 150, 12, 15);

//helper function for copying an element a bunch of times.
function copy(element, quantity) {
		if (typeof(element) === "string") {
			element = document.querySelector(element);
		var parent = element.parentNode,
				type = element.nodeName,
				a = [],
		while (--quantity > -1) {
			child = document.createElement(type);
			parent.insertBefore(child, element);
			child.outerHTML = element.outerHTML;
		return a;

//helper function for building the swarm
function swarm(elements, x, y, duration, wiggles) {
		elements = gsap.utils.toArray(elements);
		var tl = gsap.timeline(),
			  i = elements.length,
		duration = duration || 2;
		while (--i > -1) {
			delay = Math.random() * duration;
      //set to random color
      gsap.set(elements[i], {backgroundColor:"hsl(" + (Math.random() * 360) + ",80%,40%)"});
      //animate x and y separately so that they're more randomized (putting x and y in the same tween using the same ease would make the changes coincide and always travel diagonally)[i], duration, {x:"+=" + x, repeat:-1, ease:CustomWiggle.create("", {type:"random", wiggles:wiggles})}, delay)
			  .to(elements[i], duration, {y:"+=" + y, repeat:-1, ease:CustomWiggle.create("", {type:"random", wiggles:wiggles})}, delay);
    tl.time(duration); //jump ahead so that we start with everything spread out. 
		return tl;