Static Site on GitHub Pages

I need a small, completely static website that I can share via a simple link with zero ongoing costs. The site will live on GitHub Pages (yourname.github.io), so please set up the repository, push the code, and enable the public URL.

Core requirements
• Design: clean, professional look that stays responsive on mobile.
• Contact: a visible WhatsApp “Chat Now” link or button that opens the user’s WhatsApp with my number pre-filled.
• Payments: embed a working Razorpay checkout (one-time payment) so visitors can pay without leaving the site.
• Hosting & domain: configure GitHub Pages, confirm the live sub-domain, and give me both the repo and the final URL.

Acceptance criteria
1. I can open the URL on any device and the site loads instantly.
2. WhatsApp link opens the chat with no errors.
3. Razorpay payment completes a test transaction in sandbox mode.
4. All source files are in my GitHub account with a clear README explaining how to update text or images.

Handle HTML, CSS (or a lightweight framework like Tailwind if you prefer), and any JavaScript needed for the checkout. No server-side code—everything must stay static. Once done, transfer the repository ownership to me and confirm the site remains live.