Software Architecture Document for a game

Hey guys, I don't know if this is the right place for this, but I have a question. I need to write an Software Architecture Design Document for my final year project, which is a game. I could only find examples on internet for applications. I'm not really sure how I should write it. I researched about it and looked at some examples, so I have an idea of what it is. I'm not really sure of what I could write as a use-case, or to the logical view part. My game is not online, it is an offline mobile rpg game.

Any help will be appreciated!