Did i interrupt the dark period?

I have 2 plants under a desk on a shelf. When its in the 12 hours of dark the lights go off but the room light may come on at times is that ok? its still very dark under the desk but you can still see the plant but is is hard to see.

there shouldn't be any light leaking through the cracks...Complete darkness or the plant could hermie

its ok to have the lights on for a couple minutes without going back into veg, going hermie, or stalling the flowering process

...but you should try to avoid it if you can...