1. Pushing elements down only works, when
(a) the accordion isn’t pinned (Pinned object shouldn’t affect other objects.
(b) the accordion isn’t opened and overlapping elements in design mode.
2. One accordion uses the same "overlap" state across all breakpoints. If you want it to overlap in one, and not overlap it in a different breakpoint, you have to use a different accordion and hide the other one by using right click "Show/Hide in Other breakpoints"