CSS code needed? Exit app when on bottom bar nav page

I would like my app to exit/close when on a bottom nav bar page.

currently: if you were to click each bottom nav icon, you would have to "go back" through each page that you clicked until eventually exiting the app.

request: I want to be able to exit the app if on a bottom nav page. no matter how many bottom nav pages were clicked. Basically exit/close app at any point if left on bottom bar nav page