Another one of those nuances that I cannot really see any pattern to is when to use the words "soir" or "nuit". "Soir" seems to be used more frequently with the phrase "every night" ("tous les soirs", "chaque soir") but not exclusively. Every now & then I see "tous les nuits" or "chaque nuit" for the same phrase.
Should "nuit" be used only when there is a specific time frame, like when somebody works a night shift or the specific time is given that makes it obvious that the action is taking place "at night", & "soir" be used in a more generic sense?