Cross-Platform Store Management Software

I’m ready to commission a web-based store management system that runs smoothly on every modern browser and adapts perfectly to desktop, mobile, and tablet screens. The core features I need from day one are:

• Inventory management so I can add, edit, track, and automatically alert low-stock items.
• Real-time sales tracking with clear dashboards, basic reporting, and export options.
• Customer management that lets me create profiles, view purchase history, and segment contacts for marketing.

The interface must be fully responsive, touch-friendly, and tested on Chrome, Safari, Edge, and Firefox. I’m open to the framework or language you prefer—as long as the code is clean, well-documented, and easy to maintain.

Deliverables I expect:
1. A deployed, browser-based application accessible from desktop, mobile, and tablet.
2. Source code with installation notes and an ER diagram or equivalent schema documentation.
3. A short video or live walkthrough demonstrating the three core modules in action.
4. Post-deployment support for minor fixes during the first month.

Please outline your proposed tech stack, milestones, and estimated timeline when you place your bid.

I will give clear requrement doc once u guys bid this