Featured images in section cards

A card’s featured image declares the width its layout box can occupy, so the browser fetches a variant sized for a card rather than for a full-width image.

Cards render featured.webp through be-best/layouts/_partials/images/image-variants.html, which already emits webp and jpeg srcsets at 320, 640, 960, 1280, 1600 and 1920. The hint that drives the choice is wrong for a card: all 12 srcsets on public/post/index.html read sizes="(min-width: 1024px) 100vw, 50vw", while be-best/layouts/_partials/posts/card.html sits in be-best/layouts/post/section.html:6, a grid of one column below 768px, two columns to 1280px and three columns above, inside a .container with a 1px border, padding: min(2em, 10%) and a 16px gap, set in a main gutter of min(30px, 7%). At a 1280px viewport that leaves 372px per card, so 744px is needed at 2x density, yet the current hint sends the browser to the 1920w variant. For garden/featured.webp that is 363 KB against 135 KB at 960w.

Featured images in section cards

• image-variants.html takes the sizes hint from its caller, and the card path passes one that names the 768px and 1280px breakpoints and the resulting card widths.
• A card srcset stops at 960w: no 1280, 1600 or 1920 variant is generated for a card image.
• The post page keeps the existing full-width hint; only the card path changes.
• No page is illustrated by an ancestor section’s image: the inherit flag and the .Parent lookup are deleted, a hero is read from the page’s own bundle as a card image already is, and the decision that a featured image is shown only when it is unique to a page is recorded in the decision record.

Acceptance Criteria

• grep -o 'sizes="[^"]*"' public/post/index.html reports one hint only, and it names the 768px and 1280px breakpoints.
• The widest candidate in any card srcset on public/post/index.html is 960w.
• At a 1280px viewport and 2x density the featured image fetched per card is the 960w variant: 135 KB for garden/featured.webp, not the 363 KB 1920w file.
• public/post/garden/spring-2021-try-again/index.html is byte-identical to the build before the change. Its ladder has always stopped at 960w: its featured.webp is 1230px wide, so the source caps the ladder below 1280. Page-level heroes with a wider source, as public/post/cryengine/matrices-vectors-quaternions-and-cryengine-3/index.html at 1920w, still list 1280, 1600 and 1920 with the full-width hint.
• pnpm run test passes.
• grep -rn '\.Parent\|inherit' be-best/layouts/_partials/images/ reports nothing: the fallback has no code left behind, and images/featured.html, written for the two lookup paths, is folded into featured-image.html.
• No page is drawn with an ancestor section’s image. For each page under public/, no featured_h* URL on that page names a directory above the page’s own: 0 pages, against 95 pages and 1140 such URLs in the build before the change. 37 pages render a featured image, down from 132: the 95 that lose a hero are articles whose bundle carries no featured.webp.
• Listings are byte-identical to the build before the change: public/index.html and public/post/index.html are unchanged, as a card already read the bundle of the page it lists. Pages that own their image, as public/post/garden/spring-2021-try-again/index.html, are unchanged too.

Not in scope

• The placeholder class no rule styles on cards: p2-is-card-lqip-placeholder-unused.
• Alt text and captions from image metadata: p2-us-card-image-alt-text.
• The section-image fallback that repeats one image across a listing: p2-is-card-image-parent-fallback.
• Variant quality and weight: p2-us-image-processing.

Notes

• Completing the last item removes the page-hero half of p2-is-card-image-parent-fallback, which had kept the fallback for pages; the card’s own image path is untouched.