Scroll down and the section locks; the row of project photos slides sideways instead, then the page carries on.
✕ Breaks rule: pinned horizontal scroll Scrolling down moves things sideways, which nobody expects on a phone; the page feels frozen, the last photos are effectively hidden, and keyboard and screen-reader users can't reach them in order.
Best for: Architects and design studios with 4-6 curated projects, seen on desktop. How: ScrollTrigger pins the section for exactly the track's extra width and scrubs x. No JS: a normal swipeable strip. Weight: 1.3 KB gzipped (our CSS + JS) + GSAP from jsDelivr: GSAP core 28.3 + ScrollTrigger 18 KB gzipped. Plugins: ScrollTrigger. Page-level effect: it takes over the whole page, so it runs inside the phone frame below (open it full screen to try it at full size).