My brain goes straight to like a cross between calming zen humming of slowly changing pitch but with an eerie-ness to it, maybe a low droning bass that's hard to hear, because you can kinda feel it inside. Maybe echoing small sounds hear and there. Maybe add a randomized feedback sound when you click an answer.
But that's just my brain haha. I'm sure there are a lot of different ways of approaching it that will give off similar or better effects! Best of luck!! Look forward to seeing how it goes. I will give you a follow!