void setup() {
  size(800, 600);
  background(255); // white background
  noStroke();

  // De Stijl color palette
  color[] palette = {
    color(0, 125, 125),    // teal
    color(0, 0, 255),    // blue
    color(255, 221, 0),  // yellow
    color(0),            // black
    color(200)           // grey
  };

  int gridSize = 100;
  int padding = 18; // thicker white space between boxes

  for (int x = 0; x < width; x += gridSize) {
    for (int y = 0; y < height; y += gridSize) {
      if (random(1) < 0.5) {
        fill(palette[int(random(palette.length))]);

        // Random width and height in multiples of gridSize
        int w = gridSize * int(random(1, 3)); // 1 to 2 grid units wide
        int h = gridSize * int(random(1, 3)); // 1 to 2 grid units tall

        // Ensure the shape fits inside the canvas
        if (x + w <= width && y + h <= height) {
          rect(x + padding / 2, y + padding / 2, w - padding, h - padding);
        }
      }
    }
  }
}