some observations while calculating the battle UI offsets.
It looks like the battle UI is scaled down to the next lowest16:9 ratio regardless if it would fit the existing game window size
the default game window of 1280x720 is already a 16:9 aspect ratio, so no downscaling is needed
however, the game downscaled to the next lowest 16:9 ratio increment.
which results in small black bars around the battle UI.