My other thought on Severance is that the blue/red/green thing reminds me a lot of The Matrix. I can't decide if I've simply watched The Matrix too many times or if it is intentional (I think it very well could be), but red seems to be associated with the outies (at least in the intro animation), blue with Lumon (eg. their lanyards), and green... doesn't have as strong of a symbolic meaning/association to me, but there is a lot of green in their offices. I'll figure it out, I guess.
Anyway, I think the red/blue thing is interesting in terms of... Mark has a white button-down, Dylan has a light blue one, and Irving has a darker blue one. Helly generally doesn't wear blue (but she did when she left the break room), and it feels worth noting that she's a redhead? I just checked and, like, yeah she has her light blue skirt, but that doesn't show up in as many shots. I'm going to ignore it.
Also, now that I think of it, Mark's book is also red, while the handbook is blue.
#also Petey's robe is red and blue striped
#credit to my wife for noticing
#had to make an account just to tell you this