It has a light. How does the dog turn it on?
I’d imagine it’s either a motion sensor or the light itself is a push-button. Most likely the former.
Dogs don’t see with their eyes when it’s dark. Why would a dog need a light? They have a nose.
I dunno my dog can’t see that well in the dark. She just sorta whines and asks to be picked up and put on the bed, or takes forevor jumping off.
I doubt that is entirely based in sight.
When Minnie was alive she bumped into things in the dark because she was going blind. If there was light she had an easier time seeing stuff, she still ran into things on occasion, but not as much as she did in the dark.
Same thing with my dog before Minnie, Audrey. Audrey began to get cataracts later in life and light helped her from bumping into stuff and getting stuck behind things.
Dogs have some many troubles. Humanity did the species something of a disservice by altering their lineage. Wolves don’t have nearly as much trouble.