createCanvas(windowWidth, windowHeight);

  noLoop();

}

​

let margin = 25;

let sqPerRow = 8;

let sqPerCol = 8;

​

function draw() {

  background(220, 10, 100);

​

  let rowWidth = width - 2 * margin;

  let colHeight = height - 2 * margin;

​

  let sqWidth = rowWidth / sqPerRow;

  let sqHeight = colHeight / sqPerCol;

​

  for (let col = 0; col < sqPerRow; col += 1) {

    let xPos = col * sqWidth + margin;

​

    for (let row = 0; row < sqPerCol; row += 1) {

      let yPos = row * sqHeight + margin;

​

      if (col % 2 == row % 2) {

        fill(0);

      } else {

        fill(255);

      }

      rect(xPos, yPos, sqWidth, sqHeight);

    }

  }

}

​