// heart.js —— 心之所向，行之所至
function placeOne(x, y) {
  const el = document.createElement('div');
  el.style.left = x + 'px';
  el.style.top  = y + 'px';
  document.body.appendChild(el);
}

for (let t = 0; t < Math.PI * 2; t += 0.02) {
  const x = 16 * Math.sin(t) ** 3;
  const y = 13 * Math.cos(t) - 5 * Math.cos(2 * t);
  placeOne(x, y);
}