.justify-content-end:
Takes the basic nav from above and adds the .nav-tabs class to generate a tabbed interface.
Take that same HTML, but use .nav-pills instead:
Force your .nav’s contents to extend the full available width one of two modifier classes. To proportionately fill all available space with your .nav-items, use .nav-fill. Notice that all
horizontal space is occupied, but not every nav item has the same width.