Fix viewport about zombielab HOT 1 OPEN

I've tried using vh and vw css units, to some success. The game scales excellently, all items sizes immediately reflected for any resolution.
However, there were some issues related to [I believe] fractions. two wall pieces placed in the same manner (to create longer, continuous wall) ended up getting different widths. This was getting even more apparent when moving the team and animation position change - all walls and doors were flickering during the animation.
For now I've dropped the idea of using vh/vw (it's left open on a branch), right now it appears to suffice setting viewport height to 320px and using that as reference. There is some empty space left at the bottom and I definitely need to solve that, but it's not a priority anymore, since the entire game nciely fits the screen and there's no scrolling anymore.

from zombielab.