Block Game

import pygame

BACKGROUND_COLOR = (0,0,0)
ball_color = (0, 255, 0)
paddle_color = (255, 0, 0)
block_color = (
    (0, 0, 255),
    (0, 255, 255),
    (255, 0, 255),
    (255, 255, 0),
)
ball_speed = 5
paddle_speed = 5

block_length, block_height = 90, 60

pygame.init()
WIDTH, HEIGHT = 900, 600
window = pygame.display.set_mode((WIDTH, HEIGHT))
run = True
clock = pygame.time.Clock()

class Paddle(pygame.sprite.Sprite):
    def __init__(self):
        super().__init__()
        self.image = pygame.Surface((150, 30))
        self.image.fill(paddle_color)
        self.rect = self.image.get_rect()
        self.rect.center = (WIDTH//2, HEIGHT-30)

    def update(self):
        keys = pygame.key.get_pressed()
        self.dx, self.dy = 0, 0
        if keys[pygame.K_LEFT]:
            self.dx -= paddle_speed
        if keys[pygame.K_RIGHT]:
            self.dx += paddle_speed
        self.rect.move_ip(self.dx, self.dy)

class Ball(pygame.sprite.Sprite):
    def __init__(self):
        super().__init__()
        self.image = pygame.Surface((30,30))
        self.image.fill(ball_color)
        self.rect = self.image.get_rect()
        self.rect.center = (WIDTH//2, HEIGHT//2)
        self.dx, self.dy = ball_speed, -ball_speed

    def update(self):
        if self.rect.top < 0:
            self.dy = ball_speed
        if self.rect.left < 0:
            self.dx = ball_speed
        if self.rect.right > WIDTH:
            self.dx = -ball_speed

        self.rect.move_ip(self.dx, self.dy)

class Block(pygame.sprite.Sprite):
    def __init__(self, hits, x, y):
        super().__init__()
        self.hits = hits
        self.image = pygame.Surface((block_length, block_height))
        self.image.fill(block_color[hits-1])
        self.rect = self.image.get_rect()
        self.rect.center = (x, y)

    def update(self):
        if self.hits <= 0:
            self.kill()
        self.hits -= 1
        self.image.fill(block_color[self.hits-1])

player = Paddle()
ball = Ball()

elements_group = pygame.sprite.Group()
blocks_group = pygame.sprite.Group()

elements_group.add(player)
elements_group.add(ball)

for y in range(10, HEIGHT//5, block_height + 5):
    for x in range(10, WIDTH, block_length + 5):
        b = Block(1, x, y)
        blocks_group.add(b)

while run:
    window.fill(BACKGROUND_COLOR)
    clock.tick(90)

    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            run = False

    if player.rect.colliderect(ball.rect):
        ball.dy = -ball_speed

    b = pygame.sprite.spritecollideany(ball, blocks_group)
    if b:
        ball.dy *= -1
        b.update()

    elements_group.update()
    elements_group.draw(window)
    blocks_group.draw(window)
    pygame.display.update()
pygame.quit()