function setup() {

  createCanvas(windowWidth,

               windowHeight);

  background(200, 0, 100);

  frameRate(600);

}

function draw() {

  fill(0, random(100, 255), random(200, 255), random(0, 255));

  noStroke();

  ellipse(random(0, width), random(0, width), random(1, 50));

}