I built a scroll-driven product page with a 3D lamp that rotates as you scroll. Looked great on desktop. Then I opened it on my phone and the frame rate dropped to about 12 fps. Not usable.

So I rendered stills from the scene at each scroll position (WebP, transparent background) and swapped them in under 768 px. Same choreography, same finishes you can pick, same story. The phone just shows photos of the lamp instead of drawing it live. People who set prefers-reduced-motion get the stills too.

The page scores 99 on Lighthouse mobile now. You can try it: https://orbit-lamp.vercel.app (scroll on your phone, then on desktop, and compare).