KeelrLeek
0878659f6a
The pane could scroll ~850px (1971px at a tall window) past the last content pixel: at max scroll ZERO of 11 release rows were on screen, the whole viewport empty page. The sheet is 300vh of absolutely positioned decoration, and an abs-positioned descendant extends its scroller's scrollable overflow. .content's scrollHeight tracked the sheet's box — pin flow origin + the sheet's live translate + 300vh — instead of the page. Because that translate is scroll-driven, the range also breathed with scroll position and depended on scroll history: the same scrollTop measured 4167, 4329 and 4368 depending on the route taken. Hiding the sheet gave exactly 1797, the page plus the pane's padding-top. Wrap the sheet in a .sheetclip box with overflow: clip, sized to the pane's client box, so the sheet paints exactly the region the pane can show and contributes nothing to the scroll range. - The clip box is ABSOLUTE and the pin stays height: 0. Sizing the pin itself and cancelling with a negative margin-bottom leaves +24px behind — the margin collapses against the neighbouring height-0 pins and walks the hero zone from 24 to 48. Out of flow there is no margin to collapse, and the sticky constraint is untouched. - overflow-clip-margin is not an option for the sheet's 28px bleed: it re-expands the overflow region right back to 2440. The bleed moves onto the clip box instead. - The sheet's offsets are now clip-box relative. --band-from-pin is pin-relative and the box sits --pin-origin above the pin, so the two cancel: --band-from-pin + --pin-origin is --band-top. - --frame-h (measure()'s scroller.clientHeight) becomes unconditional. It fed the scroll-driven-only .fade-frame; .sheetclip needs it on both branches. Setting it on the fallback path is inert — .fade-frame's rule lives inside the @supports block and never matches there. Verified live against the pre-change rendering at identical scrollTop, each comparison bracketed by two baseline captures so the hero's 20s rotation could not be mistaken for a difference: 0 differing pixels at four of five stops (the fifth is one chip's hover ring, 83px), hero zone and scrollbody unmoved at every stop. Scroll range is now content-exact with the clip box flush to the pane at 1280x800, 1600x1100, 1100x620 and 1920x1400, and across artists with 4, 10, 11 and 22 rows. At max scroll all 11 rows are on screen instead of none.