better-accessibility v1.0.0A

Immutable. This exact content is served forever at /api/v1/blob/435b3e6703e37556.

---
name: better-accessibility
description: "Accessibility engineering for product interfaces, from focus states and keyboard support to ARIA, forms, and screen readers. Use when building or reviewing UI components, modals, menus, forms, custom widgets, or when the user says make this accessible or reports keyboard or screen-reader issues. Triggers on accessibility, a11y, WCAG, aria, focus ring, focus-visible, focus trap, keyboard navigation, tab order, tabindex, screen reader, sr-only, aria-live, alt text, hit area, touch target, prefers-reduced-motion, autoplay, toast duration, skip link, semantic HTML, aria-label, form errors, disabled buttons, not keyboard accessible."
license: MIT
metadata:
  version: "1.0.0"
---

# Accessibility that comes with the craft

Accessibility is not a compliance checkbox bolted on at the end; it is the floor for interface craft. Most of it is free if you use the platform: native elements ship with keyboard support, real labels announce themselves, and a visible focus ring is one CSS rule. Apply these principles when building or reviewing UI code, and match the project's existing styling system (Tailwind vs. plain CSS vs. CSS-in-JS) when applying fixes.

When reviewing, walk the interface as a keyboard-only user first (every flow must complete without a mouse), then as a screen-reader user: does each control announce a name, a role, and its state? When unsure, prefer the platform default over a custom rebuild, and remove ARIA rather than add it.

Rendered-pair contrast measurement and color remediation are covered by the `better-colors` skill; visual text sizing and iOS input zoom by `better-typography`; spatial RTL layout by `better-layout`.

## Quick Reference

| Category | When to Use |
| --- | --- |
| [Focus & Keyboard](references/focus-and-keyboard.md) | Focus rings, skip links, tabindex, focus trapping, APG keyboard patterns |
| [Semantics & ARIA](references/semantics-and-aria.md) | Native elements first, button vs link, landmarks, accessible names, disabled states |
| [Forms](references/forms.md) | Labels, autocomplete, error messaging, input types |
| [Screen Readers](references/screen-readers.md) | Visually hidden content, live regions, toasts, alt text, SVG |
| [Hit Areas](references/hit-areas.md) | Target sizes, expanding hit areas, collision rules |
| [Motion & Zoom](references/motion-and-zoom.md) | `prefers-reduced-motion`, autoplay and timed UI, 200% zoom, reflow, rem vs px |

## Core Principles

### 1. Native Elements First

The first rule of ARIA: don't use ARIA when a native element exists. `<button>` for actions, `<a href>` for navigation (it must support Cmd/Ctrl/middle-click), never `<div onClick>`. No ARIA is better than bad ARIA.

### 2. Visible Focus Rings

Style `:focus-visible`, not bare `:focus`, so keyboard users get a ring and mouse users usually don't. Prefer the browser's unmodified focus indicator. If the design needs a custom ring, use a project focus token or another explicit color and verify the complete indicator against every adjacent color it crosses; `currentColor` is acceptable only after the same check. Use at least a `2px` solid perimeter or an equivalent visible area. Never use `outline: none` without a verified replacement, and preserve system colors in forced-colors mode.

### 3. Full Keyboard Support

Every pointer interaction needs a keyboard path, following the ARIA APG patterns: Escape closes overlays, arrow keys move within composite widgets (tabs, menus, listboxes), Tab moves between widgets, Enter and Space activate. Only `tabindex="0"` (join the natural tab order) and `tabindex="-1"` (programmatic focus), never positive values, which break the natural order. Composite widgets use roving tabindex: the active item is `0`, all others `-1`.

### 4. Trap and Restore Focus

Modals set `inert` on the background content, move focus inside on open, and return focus to the trigger on close. Add `overscroll-behavior: contain` so background content doesn't scroll.

### 5. Minimum Hit Area

WCAG 2.5.8's Level AA baseline is a 24×24 CSS-pixel target or one of its five defined exceptions: `Spacing`, `Equivalent`, `Inline`, `User Agent Control`, and `Essential`. For easier activation, aim for 44×44px in touch contexts and 40×40px in desktop interfaces when density permits. Extend with a pseudo-element if the visible element should stay smaller. Never let extended hit areas overlap.

### 6. Label and Type Every Control

Every input gets a `<label for>` or wrapping `<label>`; a placeholder is never a label, and label and control share one hit target: no dead zones between a checkbox and its text. Add `autocomplete` with a meaningful `name`, and the correct `type` and `inputmode` for the keyboard. Never block paste; users paste passwords and one-time codes.

### 7. Errors That Announce

Keep submit enabled until the request starts, then disable with a spinner while keeping the original label. Validate on submit: mark failing fields with `aria-invalid="true"`, point `aria-describedby` at the inline error text, and focus the first invalid field. Use native `disabled` when a native control is genuinely unavailable. Use `aria-disabled="true"` only when retaining focusability or discoverability is intentional; then block pointer, keyboard, and form behavior in code and style the state explicitly.

### 8. Accessible Names Everywhere

Icon-only buttons need a descriptive `aria-label`. Visible label text must appear in the accessible name. Decorative elements get `aria-hidden="true"`, never on a focusable element.

### 9. Don't Rely on Color Alone

Status needs a redundant cue: icon, text, or underline alongside the color. Determine which contrast requirement applies from the content and state, then use `better-colors` to measure the rendered foreground/background pair; that skill decides which algorithm settles the verdict and will answer in WCAG ratios whenever a conformance level is named. Without it, still report the pair: name the foreground and background you resolved, state the WCAG level that applies, and mark the ratio **Not measured** rather than guessing — an unmeasured pair is a finding about missing evidence, not a passing check. When contrast fails, report the pair and the requirement it misses; do not change the project's colors unless asked.

### 10. Honor prefers-reduced-motion

Wrap motion in `@media (prefers-reduced-motion: no-preference)` so it is opt-in. Under reduced motion, replace slides and scales with opacity crossfades, and stop parallax and auto-advancing UI — carousels that rotate themselves, auto-scrolling tickers. This is about motion the interface starts on its own, not about media playback: an autoplaying video is governed by the pause-control rule below, which applies regardless of the preference. Independent of the preference: autoplaying media needs a visible pause control, and toasts carrying actions or errors stay until dismissed.

### 11. Announce Dynamic Content

Use `aria-describedby` for field-specific validation, a polite live region (`role="status"`) for non-urgent updates not tied to a control such as toasts or result counts, and `role="alert"` only for urgent errors not tied to a control. For reliable repeated polite announcements, render a stable empty region before updating its text; dynamically inserted alerts have different support and must be tested with the target screen readers.

### 12. Alt Text by Purpose

Decorative images get `alt=""`, informative images describe the meaning, functional images describe the action: a search icon button is `alt="Search"`, not `alt="magnifying glass"`.

### 13. Structure Is Navigation

Use headings that describe their sections and form a coherent outline; one page-level `<h1>` and properly nested levels are the recommended default, not standalone WCAG pass/fail rules. Expose one visible primary `<main>` landmark. When repeated navigation or chrome precedes it, make a "Skip to content" link the first focusable element. Anchored headings get `scroll-margin-top`.

### 14. Survive Zoom and Text Resize

The page must work at 200% zoom and reflow at 320px width without horizontal scrolling. Use `min-height` instead of fixed `height` on text containers, prefer `rem` breakpoints where they fit the codebase's conventions, and never use `user-scalable=no` or `maximum-scale=1`.

### 15. Keep the Focused Element Visible

WCAG 2.2 SC 2.4.11 (AA): when a component receives keyboard focus, it must not be *entirely* hidden by author-created content. Sticky headers, fixed footers, cookie banners, and floating action bars are the usual culprits — Tab into a control that scrolls under a sticky header and the focus ring is invisible even though focus is correct.

Set `scroll-padding-block` on the scroll container to at least the height of the fixed chrome so programmatic scrolling stops short of it, and check the first and last focusable element of every long form, which is where this fails first. Note the criterion says *entirely* hidden: partial obscuring passes AA and fails the stricter 2.4.12 (AAA).

### 16. Give Dragging a Single-Pointer Alternative

WCAG 2.2 SC 2.5.7 (AA): any functionality operated by dragging must also be achievable with a single pointer without dragging — unless dragging is essential or the behaviour belongs to the user agent. Reorderable lists, sliders, kanban boards, drag-to-resize panes, and map panning are the common cases.

Keyboard support alone does not satisfy this: the criterion is about pointer input, so a sortable list with arrow-key reordering still needs a tap-reachable alternative such as move-up/move-down buttons or a menu. Dragging may remain the primary interaction; it just cannot be the only one.

### 17. Make Hover and Focus Content Dismissible, Hoverable, Persistent

WCAG 2.2 SC 1.4.13 (AA): content revealed on hover or focus — tooltips, popovers, hover cards — must satisfy three things. **Dismissible**: it can be dismissed without moving pointer or focus, which in practice means Escape. **Hoverable**: the pointer can travel from the trigger into the content without it vanishing, so no gap between them and no `pointer-events: none` on the panel. **Persistent**: it stays until the trigger is released, the user dismisses it, or the information stops being valid — never on a timeout.

The frequent failure is a tooltip bound to `mouseleave` on the trigger alone: moving toward the tooltip crosses a dead zone and it disappears before it can be read. The exception is narrow — it covers only presentation the user agent controls, such as a native `title` tooltip.

## Common Mistakes

| Mistake | Fix |
| --- | --- |
| `outline: none` to remove the focus ring | Style `:focus-visible` instead; mouse clicks won't show it |
| Custom focus color assumed to work everywhere | Verify the full indicator against every adjacent color and in forced-colors mode |
| `<div onClick>` for a button or link | `<button>` for actions, `<a href>` for navigation |
| Placeholder used as the only label | Add a visible `<label for>`; placeholders disappear on input |
| Positive `tabindex` to fix focus order | Fix the DOM order; only use `0` and `-1` |
| Repeated polite update inconsistently announced | Keep a stable empty status region and update its text; test the target screen readers |
| `assertive` live region for a routine toast | Use `polite`; reserve `assertive` for errors |
| `aria-hidden="true"` on a focusable element | Remove it or make the element non-focusable |
| Functional icon alt describes the picture | Describe the action: `alt="Search"`, not `alt="magnifying glass"` |
| `maximum-scale=1` to stop iOS input zoom | 16px input font on mobile (see `better-typography`); never block zoom |
| Submit disabled until the form is valid | Keep it enabled; validate on submit and focus the first error |

| Focused control scrolls under a sticky header | `scroll-padding-block` on the scroller at least the height of the fixed chrome (SC 2.4.11) |
| Reorder, resize, or slider works only by dragging | Add a single-pointer path: move buttons, a menu, or tap-to-place (SC 2.5.7) |
| Tooltip vanishes when the pointer moves toward it | No gap between trigger and panel, no `pointer-events: none`; dismiss on Escape (SC 1.4.13) |
| Tooltip auto-hides on a timer | Keep it until the trigger is released or the user dismisses it |
| `focusable="false"` carried on modern decorative SVG | `aria-hidden="true"` and no focusable descendant; drop the legacy attribute |

## Severity

- `HIGH` prevents a task, hides content from assistive technology, or creates a systemic accessibility failure.
- `MEDIUM` makes an interaction meaningfully harder.
- `LOW` is isolated polish.

## Review Output Format

Use this format only when the user asks for a standalone accessibility review. When `better-interface` orchestrates the review, provide domain evidence and findings to that skill and let its output format, severity scale, consolidation rules, cap, and verdict take precedence.

Present the standalone review in two parts.

### Findings

Group all confirmed findings by principle. Use a markdown table with **Severity**, **Location**, **Before**, **After**, and **Why** columns. Never use separate "Before:" / "After:" lines.

- **Location**: cite `path/to/file:line`. If the artifact has no source files, cite the exact screen and component instead.
- **Before / After**: show the current implementation and an actionable replacement.
- **Why**: name the violated principle and its user impact.

Consolidate a repeated systemic issue into one row and list every affected location. Omit principles with no findings.

### Example

#### Accessible names everywhere

| Severity | Location | Before | After | Why |
| --- | --- | --- | --- | --- |
| HIGH | `src/Dialog.tsx:42` | `<button><XIcon /></button>` | Add `aria-label="Close"`; mark the icon `aria-hidden="true"` | The icon-only control has no accessible name |
| HIGH | `src/Nav.tsx:18` | `<a href="/settings"><GearIcon /></a>` | Add `aria-label="Settings"` | The link destination is unavailable to screen readers |

#### Visible focus rings

| Severity | Location | Before | After | Why |
| --- | --- | --- | --- | --- |
| HIGH | `src/button.css:12` | `button:focus { outline: none; }` | `button:focus-visible { outline: 2px solid; outline-offset: 2px; }` | Keyboard users cannot see focus |
| HIGH | `src/Menu.tsx:31` | `focus:outline-none` | `focus-visible:outline-2 focus-visible:outline-offset-2` | Menu navigation has no visible focus indicator |

#### Errors that announce

| Severity | Location | Before | After | Why |
| --- | --- | --- | --- | --- |
| HIGH | `src/EmailField.tsx:27` | Error shown only as `border-red-500` | Add `aria-invalid="true"` + `aria-describedby="email-error"` with inline error text | Color alone neither explains nor announces the error |
| MEDIUM | `src/SignupForm.tsx:64` | Submit disabled until the form is valid | Keep submit enabled; on failure, focus the first invalid field | A disabled action hides what must be fixed |

#### Minimum hit area

| Severity | Location | Before | After | Why |
| --- | --- | --- | --- | --- |
| MEDIUM | `src/Toolbar.tsx:22` | `size-4` icon-only button | Extend the hit area to 44×44px with `after:absolute after:size-11` | The target is too small for reliable touch input |

### Verification and Verdict

After the findings:

1. **Verification**: list the exact checks run and their observed results, including keyboard traversal, accessible-name inspection, and screen-reader or automated checks when applicable. If a check was not run, state what still needs verification.
2. **Verdict**: `Block` if any `HIGH` finding remains, `Needs changes` if only `MEDIUM` or `LOW` findings remain, and `Approve` only when no actionable findings remain.

When there are no findings, omit the tables, state "No actionable accessibility findings", report verification, and end with `Approve`.