movie trivia: a difference in height

The difference in height between Humphrey Bogart and Ingrid Bergman changes throughout the film. This is because Bergman was actually a few inches taller than Bogart, though to create the illusion that it was vice versa, Michael Curtiz had Bogart stand on boxes and sit on pillows in some shots, or had Bergman slouch down (as evident when she sits on the couch in the "franc for your thoughts" scene).