这是我的导航栏代码的一部分。我正在尝试创建一个下拉菜单,但不幸的是,在移动设备上,当我单击切换而不是显示它已关闭的下拉菜单时。我已尝试更新所有样式表引导程序代码和链接。我在导航栏下拉菜单上尝试了其他模型,但同样的事情
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