from openpyxl import Workbook load_workbookfrom seleniumwebdrivercommonby import Byfrom selenium import webdriverimport reimport timefrom lxml import etreefrom seleniumwebdriversupportui import WebDri

要修改代码等待下一页的CSS选择器出现并点击，可以使用WebDriverWait和expected_conditions中的元素可见方法来实现。具体的修改如下：

1. 导入WebDriverWait和expected_conditions：

from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

2. 在循环内部使用WebDriverWait来等待下一页的CSS选择器出现：

# 等待下一页按钮出现
next_button = WebDriverWait(browser, 10).until(EC.presence_of_element_located((By.CSS_SELECTOR, '.ant-pagination-next > span:nth-child(1)')))

3. 点击下一页按钮：

next_button.click()

完整代码如下：

from openpyxl import Workbook, load_workbook
from selenium.webdriver.common.by import By
from selenium import webdriver
import re
import time
from lxml import etree
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

# 创建浏览器对象
options = webdriver.FirefoxOptions()
#浏览器地址
options.binary_location = r'C:\Users\yuxin\AppData\Local\Mozilla Firefox\firefox.exe'
options.add_argument('--headless')
options.add_argument('--diable-gpu')
browser = webdriver.Firefox(options=options)

#打开网站
browser.get("https://you.ctrip.com/sight/dayi3130/71986.html")
wb = Workbook()
sheet = wb.active
sheet["A1"] = "内容"
sheet["B1"] = "时间"
page_num = 1

while page_num <= 210:
    # 等待页面内容加载完成
    WebDriverWait(browser, 10).until(EC.presence_of_element_located((By.XPATH, '/html/body/div[2]/div[2]/div/div[3]/div/div[4]/div[1]/div[4]/div/div[5]/div')))
    
    page_source = browser.page_source
    tree = etree.HTML(page_source)
    div_list = tree.xpath('/html/body/div[2]/div[2]/div/div[3]/div/div[4]/div[1]/div[4]/div/div[5]/div')
    for div in div_list:
        content = div.xpath('.//div[@class="commentDetail"]/text()')[0]
        contenttime = div.xpath('.//div[@class="commentTime"]/text()')[0]
        sheet.append([content, contenttime])
    wb.save("./jc630.xlsx")
    page_num += 1
    
    try:    
        # 等待下一页按钮出现
        next_button = WebDriverWait(browser, 10).until(EC.presence_of_element_located((By.CSS_SELECTOR, '.ant-pagination-next > span:nth-child(1)')))
        next_button.click()
        time.sleep(0.3)
    except:
        break

browser.quit()

这样就可以在每一页加载完毕之后等待下一页的CSS选择器出现，并进行点击操作了