Accessibility

WCAG 2.2 Level AA is the mandatory baseline on every platform — web, iOS, Android, and the browser extension. We additionally claim a small AAA "stretch" set we already meet; we do not pursue full AAA. This section governs: where an older rule in this doc conflicts (notably any "40–50% opacity" text tier — in Philosophy, Typography, Data Source Attribution, etc.), the contrast floors here win.

Level commitment

• AA 2.2 — required. Aligns with KR (KWCAG 2.2 / 장차법), US (Section 508 / ADA → WCAG AA), and EU (EN 301 549 → 2.1 AA).
• AAA stretch — only these (already met or near-free): 2.5.5 Target Size 44px (we already mandate 44/48); 2.3.3 animation-from-interaction (reduced-motion respected); 1.4.6 7:1 contrast aspired for primary body text. All other AAA is out of scope.

Perceivable

Contrast floors — these replace the opacity tiers. Text tone is limited to contrast-validated tokens; never lower text below its floor with opacity. The 40–50% muted/caption tier is removed — captions differ by size/weight.

• Color is never the only signal (1.4.1). Active/status/error states pair color with icon, text, shape, or weight — never color alone.
• Meaningful images carry alt text / labels (1.1.1).

Operable

• Full keyboard (2.1.1 / 2.1.2). Every action reachable and operable by keyboard, no traps. (The "every navigation is a real anchor" rule already serves this on web.)
• Focus visible + unobscured (2.4.7 / 2.4.11 / 2.4.13). Every interactive element shows a focus indicator ≥ 3:1 vs. adjacent colors; never outline: none without a stronger replacement. Sticky chrome (top glass bar, FAB, bottom nav) must not cover the focused element — use scroll-padding / offsets so focus stays on screen.
• Target size 44pt+ (exceeds AA's 24px 2.5.8; meets AAA 2.5.5).
• Dragging alternative (2.5.7). Any reorder/drag offers a non-drag path (menu / buttons).
• Reduced motion — every non-essential animation respects prefers-reduced-motion / Reduce Motion.

Understandable

• Labels above fields, never placeholder-only (3.3.2); errors inline + specific, not page-level only (3.3.1 / 3.3.3).
• Accessible Authentication (3.3.8). Login / PIN / OTP fields allow paste + password managers; no transcription, memorization, or puzzle step. Applies to the PIN gate and the extension OAuth sign-in.
• Predictable navigation + consistent help location (3.2.3 / 3.2.6); no redundant re-entry of known info (3.3.7).

Robust

• Native components / valid semantic markup; name-role-value exposed (4.1.2). Web: aria-* + roles, status line aria-live. iOS: accessibilityLabel/Traits + Dynamic Type. Android: contentDescription + TalkBack + sp units.
• Reflow at 320px (1.4.10 — already mobile-first) and text resize to 200% (1.4.4 — rem / Dynamic Type / sp; never fixed-px text).

Per-platform a11y API