Navbars can utilize .navbar-toggler, .navbar-collapse, and .navbar-expand{-sm|-md|-lg|-xl} classes to change when their content collapses behind a button. In combination with other utilities, you can easily choose when to show or hide particular elements.

Use our position utilities to place navbars in non-static positions. Choose from fixed to the top, fixed to the bottom, or stickied to the top (scrolls with the page until it reaches the top, then stays there).for fixed top use .fixed-top, fixed bottom use .fixed-footer,sticky top use .sticky-top