Hi, nice stairs. I would suggest not to divide wall by parts as this will cause more narrow look. Use off-whites Colors for walls. The front wall can be painted the same wall color or from the other hand, it can be decorated with traditional home symbpls- a tree or an ornament, anyway, use plain color without any dividing. Nice touch would be if you will add some lighting like led stripe or that shown on the picture. Good luck in your renovation! Best regards, Iryna