p5js-タイル状に色を配置

sample.js

import * as p5 from 'p5';

let s = (sk) => {
  let stepX;
  let stepY;

  sk.setup = () => {
    sk.createCanvas(800, 400);
    sk.noStroke();

    sk.colorMode(sk.HSB, sk.width, sk.height, 100);
  }

  sk.draw = () => {
    stepX = sk.pmouseX + 2;
    stepY = sk.pmouseY + 2;

    for(let gridY = 0; gridY < sk.height; gridY += stepY){
      for (let gridX = 0; gridX < sk.width; gridX += stepX) {
        sk.fill(gridX, sk.height - gridY, 60);
        sk.rect(gridX, gridY, stepX, stepY);
      }
    }
  }
}
const P5 = new p5(s);