Plan step 23, containment.md § Missing ("Carousel: the uncontained
multi-aspect-ratio layout"). `<x-carousel layout="multi-aspect">` is the
layout M3 added in November 2025: each `<x-carousel-item aspect="…">`
keeps its own ratio at the row's fixed height, held inside M3's 9:16 to
16:9 range (a square by default), with 16dp leading padding, 8dp gaps,
the extra-large corner and uncontained (default) scrolling.
The keyline machinery does not fit it: an Arrangement counts items of
one size each, and every snap position and mask follows from that size.
So the layout is a plain flex row, unmasked, and carousel.js only
measures each item's resting position off the DOM, which keeps the
previous/next buttons, the arrow keys, Home/End and bring-into-view
working. The header and SKILL.md say so.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qwx5USif3wFFmxtHg5U1g9
The scrim is --md-sys-color-scrim, black in every scheme, theme and contrast level,
so the ink over it is the absolute the theme keeps rather than inverse-on-surface,
which is dark in a dark scheme (containment C-25, revisited).
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qwx5USif3wFFmxtHg5U1g9
Plan step 19, containment.md C-11. The full-screen layout was another
horizontal row with a 28px corner and a mask, where M3's "shows one
edge-to-edge large item at a time and scrolls vertically". It is now a
vertical scroll-snap column: items fill the row with no corner and no
mask, 16dp apart, no end padding, the previous/next buttons point up and
down and the arrow keys are Up and Down. The row is capped at the 840px
medium window, which with the portrait rule in the header comment is as
far as CSS can hold M3's "compact and medium, portrait only". The ported
FullScreenCarouselStrategy keylines go with it: nothing measures them
any more.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qwx5USif3wFFmxtHg5U1g9
Plan step 19, containment.md C-18. The row was the focusable `region`
and the items were not focusable at all, which is the thing M3's
accessibility page draws a Don't for: "use Tab to place initial focus on
the first carousel item", "avoid focusing on the carousel container".
Each item is now `tabindex="0"` with the focus ring drawn inside it, the
row is out of the tab order, and from a focused item the arrows move one
item (moving focus with them), Home and End go to the ends, and Space or
Enter opens one that is not fully in view.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qwx5USif3wFFmxtHg5U1g9
Plan step 19, containment.md C-12 and C-25. `padding` defaulted to 0
where M3's specs table gives every layout 16dp of leading and trailing
padding — leading only for `uncontained`, none for the edge-to-edge
`full-screen` — so the default is 16 and each layout now says which
ends it applies to (`data-padding`, `data-padding-end`). The row gains
the 8dp above and below that goes with it, without shortening the
items. The overlay label is `inverse-on-surface` instead of a literal
`white`, which no scheme or contrast profile follows.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qwx5USif3wFFmxtHg5U1g9
Multi-browse, hero, uncontained and full-screen layouts on a native
scroll-snap row, with Compose's keyline maths masking each item as it
scrolls. Completes Phase 5.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01V9NnLxnPp8vaaurb3Z1MFy
