Hit&Lock

Hit & Lock is a small puzzle PWA where players guess a four-digit number to unlock a padlock and open a treasure chest. The idea started with a simple question: could a puzzle that reveals a coupon or reward after completion be useful for business promotions? From there, the concept evolved naturally: treasure chest → lock → number-based unlocking → Hit & Blow, which became Hit & Lock. Rather than focusing on building a highly polished game from the beginning, the main goal was to test how quickly a small idea could be turned into a working product with minimal manual effort using AI-assisted development. The concept and requirements took about three hours to define, and the first playable version was built in roughly two more hours with AI assistance. After that, I refined the UI, added automated testing, Japanese and English support, PWA functionality, accessibility features, and the production environment before release. Main features: - Four-digit number deduction game - Daily puzzle and free-play mode - Japanese and English support - Hints, coins, and streak tracking - Sharing to X - Offline-capable PWA - Color-vision support - Reduced-motion support - Save and resume game progress