loading

function setup() {
  createCanvas(windowWidth * 0.9, windowHeight * 0.9);
  rectMode(CENTER);
  angleMode(DEGREES);
  nrot = int(random(6, 20));
}

function draw() {
  background(10, 30, 40);
  r = width / 10;
  r2 = width / 5;
  translate(width / 2, height / 2);
  t = frameCount;
  stroke(40, 70, 100);

  for (let i = 0; i < nrot; i++) {
    push();
    rotate((i * 360) / nrot + t / 4);
    arc(r2, 0, r, r * cos(t), 0, 180);
    pop();
  }
  for (let i = 0; i < nrot; i++) {
    push();

    fill(255);
    noStroke();
    circle(
      r2 * sin((i * 360) / nrot + t / 2),
      r2 * cos((i * 360) / nrot + t / 2),
      r / 3.5
    );

    pop();
  }
  for (let i = 0; i < nrot; i++) {
    push();
    rotate((i * 360) / nrot);
    arc(r2, 0, r, r * cos(t), 180, 360);
    pop();
  }

  border();
}

function border() {
  noFill();
  stroke(20, 50, 60);
  strokeWeight(4);
  rect(0, 0, width - 20, height - 20);
}

function mousePressed() {
  frameCount = 0;
  setup();
  draw();
}

function windowResized() {
  resizeCanvas(windowWidth * 0.9, windowHeight * 0.9);
}