Responsivess: question

I have a group A, Group B inside and a repeating group C inside B.
.A
. B
. C (repeating)

My app should be properly displayed at low res and high res screen. So I gave A a min and max heigth.
I am struggling with what heigth properties I should give B and C.

The problem now is that on a low res screen, when C gets filled with data, B gets bigger than the min height of A. So A goes to its max heigth, which is only desirable on a high res screen, not a low res one.
Can anyone give some advise?

screenshots will help here