Stacked slideboxes


I’ve been searching for a way to have two fullscreen slideboxes stacked which you can switch from one to other by scrolling vertically.
the constraint is that the use should not be able to stay ‘in between’ the two slide boxes, eg display should force to either one or the other, similarly to what happens with slides in a slidebox.
I thought a vertical slidebox could do it (each ‘vertical slide’ embedding a horizontal slidebox) but I just can’t make any of the suggestions work.

any hint ?

thanks a lot in advance !!!