A Scandinavian bedroom is about light and calm, so this scheme starts with a bright white on the walls and ceiling — warm enough to feel soft, never sterile. It bounces every bit of daylight around the room, which is exactly the point in a part of the world where winters run dark.
A pale gray gives you a gentle accent wall or the option to cool one side of the room without breaking the airy feeling. The real warmth comes from wood tan: oak floors, a simple bed frame, a stool by the window. That natural tone keeps the whites from going flat.
Finally, a soft black adds quiet contrast — a headboard, a few frames, a slim reading lamp. Use it sparingly. The whole look depends on restraint, letting white lead while wood and a little black do the grounding.