createCanvas(600, 600);

}

​

function draw() {

  background(0);

  ellipse(width / 2, height / 2, width - 100);

  push();

  fill('red');

  noStroke();

  var irisX = constrain(mouseX, 150, 450)

  var irisY = constrain(mouseY, 150, 450);

  ellipse(irisX, irisY, 150);

  pop();

​

  push();

  noStroke();

  fill(77, 2, 2);

  var pupilX = constrain(mouseX, irisX - 250, irisX + 250);

  var pupilY = constrain(mouseY, irisY - 250, irisY + 250);

  ellipse(pupilX, pupilY, 50);

  pop();

}