The page turns into a deck of full-screen panels: one swipe or wheel flick slides the next panel in.
✕ Breaks rule: scroll-jacking Every swipe jumps a whole screen, so you can't skim or stop halfway, content gets cut to one screen per idea, and find-in-page, back-to-top and the browser's own scrolling stop working normally.
Best for: One-off event or launch microsites. Not a business's main site. How: Observer (wheel, touch, pointer) blocks native scroll and calls goto(next / prev); panels slide with yPercent. Arrow keys and dots work. No JS: normal stacked sections. Weight: 1.8 KB gzipped (our CSS + JS) + GSAP from jsDelivr: GSAP core 28.3 + Observer 4.3 KB gzipped. Plugins: Observer. 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).