Shopify B2B "Ghost Store" Expert – Custom Matrix Grid & WhatsApp Integration

Short Project Summary

I am building a private B2B procurement portal for my apparel brand on the Shopify Ritual Theme. This is a "Ghost Store" for wholesale clients only. I need a developer to replace standard retail features with a high-density ordering matrix and a secure, WhatsApp-driven login system.

Scope of Work (The "Big Five"):

1. High-Density Ordering Matrix: Replace the "Add to Cart" button with a 15-color x 3-set matrix grid. It must support dynamic size-set logic (e.g., Set A: 30-36, Set B: 32-38) based on product tags.
2. WhatsApp-Only Security:Access must be restricted via **Magic Links** (Token-based URLs). Implement a **WhatsApp OTP** verification for new sessions to protect wholesale pricing (WSP).
3. Amazon-Style "Silent" Quick Add:** Add three background AJAX buttons ([+Set A], [+Set B], [+Set C]) to collection cards. **No popups or page refreshes.**
4. Proforma Workflow:** The "Checkout" button must be replaced by **"Request Proforma,"** which creates a Shopify Draft Order and generates a PDF with our bank details and a **UPI QR Code**.
5. PWA & Meta-Browser Optimization:** Integrate **Progressier PWA** for offline browsing and ensure the store is fully optimized for the **WhatsApp In-App Browser** (no auto-zoom, fixed viewports).

**Technical Requirements:**

**Theme:** Ritual (Online Store 2.0).
**Languages:** Liquid, JavaScript (AJAX), CSS.
**Design:** Minimalist, Rugged, Industrial (Carbon X Branding).