为什么pygame按钮不把我带到下一个功能？

import pygame

# 初始化pygame
pygame.init()

# 设置窗口大小
window_size = (800, 600)
screen = pygame.display.set_mode(window_size)

# 定义按钮类
class Button:
    def __init__(self, x, y, width, height, text):
        self.rect = pygame.Rect(x, y, width, height)
        self.text = text

    def draw(self):
        pygame.draw.rect(screen, (255, 0, 0), self.rect)
        font = pygame.font.Font(None, 36)
        text = font.render(self.text, True, (255, 255, 255))
        text_rect = text.get_rect(center=self.rect.center)
        screen.blit(text, text_rect)

    def handle_event(self, event):
        if event.type == pygame.MOUSEBUTTONDOWN and event.button == 1:
            if self.rect.collidepoint(event.pos):
                # 在这里执行进入下一个功能的操作
                print("进入下一个功能")

# 创建按钮实例
button = Button(100, 100, 200, 50, "下一个功能")

# 游戏主循环
running = True
while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False
        # 处理按钮事件
        button.handle_event(event)

    screen.fill((255, 255, 255))
    button.draw()
    pygame.display.flip()

# 退出游戏
pygame.quit()