I am looking for a layout displaying a grid of images.
ABC
DEF
GHI

Which, for "medium" screen size would reflow to:
AB
CD
EF
GH
I
And, at "small size", would stack:
A
B
C
D
E
F
G
H
I

Is this possible? Does anyone have code snippets that would address such a situation?

And, is it possible without relying on @media?