Toast — accessibility

Keyboard

The close button and the action button are real <button>s, so Tab reaches them.
But the toast appears without moving focus, and it lives at the end of the DOM: a keyboard user who wants the undo has to tab past the rest of the page to reach it, usually within the four seconds before it disappears. Treat the action as a convenience, never as the only way to undo.
The host is pointer-events: none; each toast re-enables them, so the page underneath stays clickable.
There is no shortcut to focus or dismiss the stack.

error toasts carry role="alert" (assertive — it interrupts); every other type carries role="status" (polite). That split is deliberate: a failure is worth interrupting for, a confirmation is not.
The host is role="region" with aria-label="Oznámení", so the stack is findable as a landmark.
The icon is decorative; the title and description are the announced content.
The close button is labelled Zavřít.
A loading toast that later resolves re-renders as a new type; the polite region announces the new title.

Both buttons take the foundation ring from ds.css (outline: 2px solid var(--accent); outline-offset: 1px).
Focus is never stolen and never restored — nothing to restore, since nothing was taken.

Computed from packages/ui/src/tokens/tokens.css:

Title .toast-t in --fg on --surface-100 (--surface-75 in dark) — 17.59:1 light, well clear in dark.
Description .toast-d uses the muted tone — 2.85:1 light, below AA; keep it genuinely secondary.
Type icons: --positive 3.10:1 light / 5.50:1 dark · --accent 4.44 / 3.83 · --warning 1.80:1 light / 9.45 dark · --critical 3.91 / 4.35. The warning icon in the light theme is far under the 3:1 non-text threshold, so the icon never carries the meaning alone — the words do.

Four seconds is below the WCAG 2.2.1 expectation for timed content, and there is no user setting to extend it. Hovering pauses, which does not help a keyboard-only user.
The action is hard to reach from the keyboard before the toast goes.
The warning icon is effectively invisible in the light theme.
Three simultaneous polite regions can queue up and read one after another.