taste-accessibility

taste-accessibility

AI-generated UI is inaccessible by default. This skill makes accessible the default. Every rule below is applied during generation — not as a fix-up pass.

1. SEMANTIC STRUCTURE (The Code Skeleton)

• One <h1> per page; heading levels never skip (h1 → h3 without h2 = failure); headings carry the page outline — test by reading only headings.
• Landmarks: <header>, <nav>, <main>, <footer>, plus <aside>/<section> with accessible names where meaningful.
• Lists for lists (<ul> for nav, features), <table> only for tabular data with <th scope> headers.
• Buttons are <button>; links are <a href>; both have visible text. Icon-only controls get aria-label matching their visible tooltip.
• Decorative images: alt="" (empty). Informative images: alt describing meaning, not appearance ("Chart: conversion fell from 18% to 9% in May" — not "a blue line chart").
• aria-hidden="true" + tabindex="-1" on decorative SVG/decor; never aria-hidden on focusable elements.

2. KEYBOARD COMPLETE (Nothing Requires a Mouse or Touch)

• Everything reachable: tab order follows visual order; no element focusable that isn't interactive (tabindex="0" only on purpose).
• Focus visible everywhere: 2px ring, 3:1 contrast vs adjacent, outline-offset ≥ 2px. Never outline: none without a replacement.
• Standard interactions: Enter activates buttons/links; Space toggles; Esc closes dialogs and menus.
• Dialogs/popovers: focus moves into the dialog on open, traps within (or the platform's native pattern), returns to the trigger on close; overlay has role="dialog" + aria-modal="true" + labeled.
• Skip link: first focusable element on every marketing page ("Skip to content"), visible on focus.
• Custom components (menu, tabs, combobox, slider): implement ARIA patterns correctly (e.g., role="tablist" with aria-selected, arrow-key navigation) or use the platform element instead — a native <select> beats a broken custom one.

3. CONTRAST & TARGETS (Exact Numbers, WCAG 2.2)

Rule	Requirement
Normal text	≥ 4.5:1
Large text (≥24px / ≥18.66px bold)	≥ 3:1
UI components & focus	≥ 3:1 vs adjacent
Pointer target size	≥ 24×24px (AA 2.2), ≥ 44×44px recommended & for touch
Spacing exception	24px targets with ≥ 24px gaps to neighbors pass

• Placeholder-only labels fail (4.1.2): every input needs a programmatically associated label (<label for> or aria-labelledby).
• Error states: never color-only — text message + icon; errors announced (aria-live="assertive" region); error messages identify the field and give the fix, not "invalid".
• Focus indicators on dark and light surfaces both; check focused state against ITS background, not page background.

4. FORMS (Generation Checklist)

• Correct type per input (email, tel, password, number, search) + correct autocomplete tokens (email, name, credit-card-number, etc.).
• required + aria-required; validation on :user-invalid styling (not just :invalid — don't punish pre-submit), with visible messages.
• One column layout for anything ≥ 4 fields; labels above inputs; hint text associated (aria-describedby) not detached.
• Multi-step wizards: progress announced, errors summarize at top, back/next keyboard-safe.

5. MOTION & COGNITION

• Everything under prefers-reduced-motion (see taste-motion §7): no parallax, no carousel autoplay, no marquees.
• No auto-playing media with sound; carousels pause on hover/focus; content doesn't move faster than the eye can read it.
• Timeouts (sessions, auto-advance): ≥ 20s warning or user control (WCAG 2.2.1).
• Plain language; expand abbreviations at first use; no emoji-only communication.

6. TESTING (Run These Checks Before Done)

1. Keyboard walk: Tab through the entire page — focus visible at every stop, order sane, nothing trapped.
2. Read with a screen reader (VoiceOver/NVDA): page title, heading outline, every control labeled, regions announced.
3. Contrast: sample every text/background pair used (at least: headings, body, muted, button text, placeholder, borders of inputs).
4. Resize: at 200% zoom (up to 1280px wide), no horizontal scroll, no text clipping.
5. Check aria-labels don't duplicate visible text unnecessarily; check no empty buttons/links exist.
6. Dark/light variants both pass (never assume one does).

7. CHECKLIST (Fail the Page If…)

• Any heading level skipped.
• Any input without an associated label.
• Any interactive element unreachable by keyboard.
• Any focus indicator invisible or outline: none without replacement.
• Any text pair below 4.5:1 (3:1 for large) that isn't a deliberate, documented exception.
• Any error communicated by color alone.
• No prefers-reduced-motion handling.
• Touch targets under 24px with less than 24px spacing.

Accessibility is not a feature. It is the interface working. Ship nothing that fails this checklist.