WALLS AND FLOOR!
Bulkheads, overhead and deck!
Watch your mouth or I'll throw you out of one of those little round windows!
White (5-U) with Dark Gray decks was standard aircraft hangar decks from pre-war, through WWII to the current day.
The photo below is recent of the Enterprise's hangar deck. No, they didn't toilet-paper it, the stramers are part of a test of the foam fire suppression system.
NavyNewsstand Photo.
Note the white bulkheads and overhead