const canvas = document.body.appendChild(

  document.createElement('canvas')

);

const c = canvas.getContext('2d');

function resize() {

  canvas.width = window.innerWidth;

  canvas.height = window.innerHeight;

  draw();

}

function draw() {

  c.clearRect(0, 0, canvas.width, canvas.height);

  c.fillStyle = 'blue';

  const iter = 300,

        halfWidth = window.innerWidth / 2,

        halfHeight = window.innerHeight / 2;

  let rad = 0, theta = 0, x, y;

  for (let i = 0; i < iter; i++) {

    x = halfWidth + rad * Math.cos(theta);

    y = halfHeight + rad * Math.sin(theta);

    c.fillRect(x, y, 5, 5);

    rad += Math.min(window.innerWidth, window.innerHeight) * 0.0015;

    theta += .1;

  }

}

resize();

window.addEventListener('resize', resize);