我正在创建一个带有图像的水平顶部导航栏。我已经准备好顶部栏（下面的代码），但我不确定如何添加第二级和第三级导航。例如，当有人将鼠标悬停在 Business Essentials 上时，我希望图像本身更改为悬停状态，并在其下方显示一个表格，这是我的子导航。也许我以错误的方式解决这个问题，但使用图像是我可以获得所要求的确切外观的唯一方法。如果有人能告诉我下一步应该做什么或给我一个参考/示例代码，我将不胜感激。
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