1HDC 08.01 - Theft Proof Bicycles Discussion

Are we limited to just the Bike Lock (to fit on a variety of bikes) or are could we design a whole bike?

EDIT: I had a spare hour and quick idea so went for a Lock… It would be better to design a steal proof bike in terms of security… are we allowed to have a go at a few concepts in these comps or is it just the one?, also is the brief just a bike lock?