我想要做的是，如果有人点击艺术，那么历史社会学和地理子菜单应该出现。当有人点击艺术时，它现在应该出现。
https://jsfiddle.net/0e7jdfza/
我尝试添加此代码https://jsfiddle.net/w3zyLmgb/代替艺术 li 和 ul 但它在下拉菜单中工作，尽管它在此下拉菜单之外工作
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