Product Stage Commerce Page is a single-product store page built around a 3D hero. A glossy torus ring stands on a pedestal, lit by a procedural studio environment (soft boxes, gradient and floor bounce computed in the shader, no textures) and shaded with a small PBR-style model: fresnel, GGX-flavoured specular, a clear-coat layer, engraved grooves and soft contact shadows. Visitors drag to orbit with inertia, use the keyboard arrows, or jump to Front / Side / Top / Detail camera presets.

Around the stage is a complete, working shop UI for a fictional brand. Five finish swatches (gloss blue, brushed gold, rose, obsidian, pearl) change the 3D material live and update the price; a size selector with a size guide, quantity stepper and Add to cart feed a slide-in cart drawer with quantity controls, remove, promo code, shipping and totals, all persisted in localStorage. Below sit feature cards, a specifications list and related items whose thumbnails are generated as inline SVG.

Everything is front end only: vanilla JS, no libraries (about 57 KB of unminified JavaScript in total). The cart is isolated in a single file with TODO: connect your API comments so you can plug in Shopify, Stripe or your own backend. It falls back to a static SVG ring without WebGL, pauses when hidden or off-screen, caps the pixel ratio and respects reduced-motion.