Decks are Standard Navy Deck Gray #20 - the same as the interwar color. Old ModelMaster had some, none in Tamiya. Look at ScaleColors or Colourcoats for out of the bottle solution
Overheads and bulkheads were white. There are some reports that the lower 5 - 6 feet were black to hide soil & stains.
In WWII The Navy Department used the Munsel Color Reference system. Many of the USN ship colors were in the “Purple-Blue” range of that system.
The Federal Standard color system would not come about until abotu 1954, with Department of Defense adoption circa 1955, supplanting the A/N (Army-Navy) color standards left over from 1946.
There’s a good, if very old, thread by EdGrune on this here:
FS37030 as equal to Deck Gray 20G, but it’s also rather an old link. So, a gain of salt will be wanted.
Many USN ships in WWII used a “slime stripe” of darck greay or near black 6-8 inches (15-18cm) up from the deck on vertical bulkheads to keepthem from discoloring dues to sawhing and the like Accedotally, used of a brick red has been reported on USN carrier hangar decks.
Either would have also been subject to individual Captain’s discretion, too–so you want refence photos to make your case.
Hangar spaces are dark by nature, even when filled with artificual light. This can make photographs complicated to interpret, especially B&W ones developed for “full saturation” (e.g., every tone of gray from pure white to pure black in the photo).
Well, there is white and then there is white; but then, the walls probably do not get washed as often as the hats, ie. they’re dirty! The basic color of my walls will be off-white turning almost grey as you get to the upper structure.