Optilang told me each room has a ceiling and I assumed, maybe he did tell me, that each also has a floor. So, I thought there were at least two floors in a car, one in the front, another in the back. maybe the trunk also has a floor.
GG is using the word floor as "story" or "level". You are using it as "lowest surface". Cars only have one floor (story), and they have only one floor (lowest surface), as far as I have ever heard of.