JainCK/openinvo ? reverse-engineered prompt

Build me a clean, modern invoice generator web app for freelancers and small businesses.

I want a simple home page that leads into an invoice creation flow where I can enter my business details, client details, invoice number, dates, line items, taxes, currency, notes, and an authorized signatory. It should calculate totals automatically, support Indian GST as well as regular tax use cases, and let me add or remove items easily.

After that, I want a live preview page that updates in real time, looks professional, and is ready to print or save as a PDF. Make it mobile friendly too, with a layout that works well on smaller screens and a simple way to open customization options on mobile.

Use a modern, minimal design with reusable UI components, and keep the whole thing fast and lightweight. If you need to look up current docs online while building it, go ahead.