I know it technically doesn't have layers, but I usually think of it as having a bottom layer, lower middle layer, upper middle layer, and top layer.
Anyway I've looked for the answer to this, and i really couldn't find anything, and the WCA isn't really too clear about it, but sorry if im completely oblivious to something:
Are black tiles/stickers legal in competitions??? because my fav cube is white so i have one side black instead of having white on white.
i really didnt think that question needed a thread of its own so im glad that i stumbled upon this thread