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<svg id="SVGcontainer" width="600" height="600">
  <circle id="circle1" cx="100" cy="100" r="30" fill="#ff5733" fill-opacity="0"/>
  <circle id="circle2" cx="500" cy="300" r="30" fill="#FFC300" fill-opacity="0"/>
  <circle id="circle3" cx="200" cy="400" r="30" fill="#8B008B" fill-opacity="0"/>
  <circle id="circle4" cx="300" cy="200" r="30" fill="#c90035" fill-opacity="0"/>
   <circle id="circle5" cx="200" cy="500" r="30" fill="#ff5733" fill-opacity="0"/>
  <circle id="circle6" cx="300" cy="300" r="30" fill="#FFC300" fill-opacity="0"/>
  <circle id="circle7" cx="500" cy="100" r="30" fill="#8B008B" fill-opacity="0"/>
  <circle id="circle8" cx="400" cy="400" r="30" fill="#c90035" fill-opacity="0"/>



                #SVGcontainer {
  position: absolute;
  left: 600px;
  top: 50px;
  border: 1px solid #CCD1D1;



                // This animation uses the Velocity.js library to make circles expand and vanish while moving to random positions.

// Access the <svg> element
var svgContainer = document.getElementById("SVGcontainer");

// Access all the child elements of <svg> (these are the <circle> elements)
var circles = svgContainer.children;

// Create an array from the collection of <circle> elements
var circlesArray = Array.from(circles);

// Specify the animation (expanding and vanishing circles that move to random positions)
function animateCircles(element) {
  // Generate random values for the following properties:
  var animationDuration = (Math.random() * (5000-3000) + 3000);
  var radius = (Math.random() * (200-20) + 20);
  var positionX = (Math.random() * (550-50) + 50);
  var positionY = (Math.random() * (550-50) + 50);
  // Specify the animation sequence
  Velocity(element, { fillOpacity: 0.75 }, { duration: 1000 });
  Velocity(element, { cx: positionX, cy: positionY, r: radius, fillOpacity: 0 }, { duration: animationDuration});

// Loop through the animation sequence 200 times
for (var i = 0; i < 201; i++) {