How do I remove the navbar on the Python flask admin page or modify the css?

admin = Admin(app, index_view=AdminIndexView()
        name='Home',
        url='/admin_manager'
    ))

admin.add_view(ModelView(Admin_en_filter, db.session))
admin.add_view(ModelView(Admin_filter, db.session))

When you create the flask admin page in this way, the navbar has the paths home, admin_en_filter, and admin_filter. What should I do if I want to get rid of the navbar? I couldn't see the navbar in the iframe place, so I gave it display:none, but it doesn't seem to work.