If you're not up all night, I wouldn't worry about it. My snakes go to bed (ie. get room darkness) when I do. And I stay up late...so, not to worry. Your snake will adapt to your hours. If you're worried about having bright light in the room all evening, you could put a dark towel over part of his home to help block some of the light. It's nice that you care enough to ask- but for the most part, a day-night cycle for snakes just means the normal room light from windows & human co-occupation.