Tiered Bundle & Save Section — No-App Multi-Add-to-Cart for Shopify

A drop-in Shopify Online Store 2.0 section that lets shoppers build a mini bundle from 2–4 of your products and add them all to cart in one click — no app, no subscription fee, no build step.

Design Pattern: A checkbox card grid (each card pre-selected) paired with a live progress bar that fills as more items are chosen, echoing the "add multiple products, no app required" bundle-section pattern that's been gaining traction in the Shopify OS 2.0 open-source community — extended here with merchant-defined quantity tiers ("Buy 2, save 10%", "Buy 3, save 15%"...) instead of a flat one-click add.
Conversion Intent: Increase average order value by making the next item feel like a small, obvious upgrade instead of a separate purchase decision.
Emotional Outcome: Effortless, reward-driven — shoppers see exactly how close they are to unlocking the next discount.

Features:
- Checkbox product-card grid, 2–4 merchant-picked products via the theme editor (no code required)
- Live tier progress bar + status line that updates instantly as items are checked/unchecked
- One click adds every selected item to cart via Shopify's native Cart AJAX API (vanilla JS, zero dependencies)
- Optional per-tier discount-code redirect (/discount/CODE) that hands off to an Automatic Discount you set up in Shopify Admin — full instructions included
- Light background/accent color controls, fully responsive (2 columns on mobile)
- Editable heading, subheading, button label, and all four tier labels
- 2-minute install: copy one .liquid file into Sections, one .css + one .js file into Assets

Download the section files (.zip) — includes the Liquid section, CSS, JS, and a full install + discount-setup README.

Delivered as a single self-contained Shopify section (Liquid + CSS + JS + install README). Single-site commercial license.