def draw():
    screen.fill((0, 0, 0))
    
    for y in range(4):
        for x in range(4):
            piece_size = 100
            piece_draw_size = piece_size - 1
            
            screen.draw.filled_rect(
                Rect(
                    x * piece_size, y * piece_size,
                    piece_draw_size, piece_draw_size
                ),
                color=(100, 20, 150)
            )