How can I stop a collapsed Bootstrap 4 navbar (or CSS menu) from pushing down the page content when it's expanded?

Answer 1

Do you want the menu to overlap the other content when it is opened? Because if so, then you could make the menu itself "absolutely positioned" (position: absolute). Make sure to put the menu inside another div that is "relatively positioned" (position: relative) so that it has sort of an anchor point to position off of!