When saying good-bye to somebody at night, when you know the other perosn is not going to go to bed, what can you say?
1: good evening
2: good night
3: have a good evening
4: have a good night
It depends on the time. It's fine to say good night if you are not going to see them again that day, regardless of whether they are going to bed nowor not. You could use it when leaving work, aslong as it was late enough.