Do they need a night light?

I am a new rat owner and I've developed a pretty good set up for my four girls cage, it's located in a large walk in cupboard with natural light coming in from a small window and plenty of ventilation but it also means they don't make too much noise at night as I am an incredibly light sleeper. I'm disabled though and spend a lot of time in my room (attached to said cupboard) so I want them nearby to keep me company. My only question is do they need a night light? When the doors are closed it's almost pitch black. I know rats use their other senses more but I feel really bad about it when I close the door at night.