Pretty nice idea! Didn't really get the "Eureka" moment there, but that's primarily because it felt a little trial and error-y, to have an eureka/aha moment I'd need to have more data points that I don't just gather from trying random combinations :P
From a UX standpoint I'd prefer to have some more fluidity in the gameplay (it feels very disorienting to lock in your combination and have it reset, instead of letting me tinker with it by modifying bits). It would help reduce the trial and error feeling as it'd let me modify my answer more cleanly and make adjustments based on intuition and previous data points.
I did really like the take on the theme though, and these are mostly notes on how you could improve the experience!
I think the concept and execution are quite clever, and the simple graphics make the objective non-ambiguous, so overall, good job on this one :D