I want to launch a small-to-medium e-commerce site that sells downloadable products only. The stack should stay lean—pure Core PHP for the application logic, MySQL for data storage, and the usual front-end trio (HTML / CSS / JavaScript) for a responsive UI. Clean, reusable, well-commented code is a must; I’ll be reviewing structure and readability as closely as I review features. Minimum functional scope • Product catalogue with file-based digital items • Shopping cart that updates in real time and preserves state across pages • Order record written to MySQL and confirmation email (no payment gateway at this stage) • Basic admin area to add, edit, or retire products and view orders • Mobile-first layout that looks solid on modern browsers Technical expectations • Procedural or lightweight MVC in Core PHP—no heavy frameworks • Clear separation of concerns (views, logic, data) • Prepared statements or PDO for secure queries • Simple install guide and SQL dump so I can recreate the database locally • Git-based handover so I can track the commit history I’m open to small UX refinements or plug-ins you’d recommend, provided they don’t bloat the codebase. The goal is a deploy-ready, maintainable solution that I can extend later with user accounts and payment gateway integration.