Flash card size and alignment in Rise 360

Hi... I have a flashcard grid with just two cards in one of my lessons. When previewing the lesson on different devices, they don't appear aligned horizontally, rather they appear one below the other. When I introduce a third card, all cards appear aligned irrespective of device resolution. At present, I require just two cards for my lesson and would like both to be aligned horizontally. Could you help with a solution to this issue?

Thank you.