[a11y][D11] Smooth scroll ignores reduced-motion preference

[BrianGenisio]

Finding

D11 — Smooth scroll ignores reduced-motion preference
Severity: minor
WCAG: 2.3.3 Animation from Interactions
Theme: both

Where

components/modal/modal.js — scrollIntoView({ behavior: 'smooth' })

Current behavior

In-modal hash link scrolling always uses smooth behavior.

Expected behavior

Use auto (or skip smooth) when prefers-reduced-motion: reduce.

Suggested approach

Safe to land with D8/D10 modal hygiene PR.

Acceptance criteria

• Reduced-motion preference disables smooth scroll-into-view
• Default motion unchanged when preference is not set

Reference

ChatCPT a11y-audits/8-5-26/audit.md → D11
ChatCPT a11y-audits/8-5-26/wave-4-plan.md → Wave 4e

[BrianGenisio]

XS — safe to include in D8/D10 modal hygiene PR (#19).

[BrianGenisio]

Verified on main after merging #24.

In-modal hash links now use scrollIntoView({ behavior: prefersReducedMotion() ? 'auto' : 'smooth' }). Covered by tests/modal-a11y.spec.js.

Closing as fixed by #24.