Section Index

Preview

Rendered from the story the storybook (a11y) CI gate runs axe against — the preview can't show something that hasn't been verified.

Install

Two equivalent paths — the URL works in any shadcn-CLI setup; the alias works once you've registered @interlace in your components.json.

npx shadcn@latest add https://ds.interlace.tools/r/section-index.json

npx shadcn@latest add @interlace/section-index

Import

Single named export.

import { SectionIndex } from '@/components/ui/section-index';

Anatomy

Extracted from the primitive's JSDoc header. The source is the only documentation that can't drift.

<SectionIndex value={2} data-testid="…">The Agenda</SectionIndex>
  p                (data-slot="section-index" — the eyebrow line)
    ├─ span        (data-slot="section-index-numeral", aria-hidden)
    ├─ span        (sr-only "Section N:")
    └─ children    (the label — string or <DecodeText>)
Fits SectionHeader's `eyebrow` slot directly.

API reference

Parsed from the type declarations in the source — the same file the install writes into your tree, so this table can't drift from the component you get.

Accessibility

Every story for this component is rendered headlessly and checked with axe-core (wcag2aa, wcag22aa, best-practice, ACT) on every PR. That gate has no continue-on-error, so what ships has zero known violations.

What follows is what static analysis can see. Axe cannot press a key and never sees an overlay open, so the operable-without-a-mouse claim lives in Behavior instead, where the keyboard path is replayed step by step.

Focus + keyboard behaviour

Native element semantics — no interaction layer to get wrong.

Focus ring (WCAG 2.2 SC 2.4.13)

Not focusable — no focus indicator required.

Reduced motion

No animation to gate.

ARIA in the source

• aria-hidden

Examples

2 more states from the same story file.

Dependencies

Base UI primitive

Native / no Base UI dependency

Lucide icons

none

NPM dependencies

none

Registry dependencies

• @interlace/theme
• @interlace/cn

Source

The full implementation — components/ui/section-index.tsx once installed.

import * as React from 'react';

// @interlace/section-index v1.0.0 — Interlace design system.
// Docs, props and live preview: https://ds.interlace.tools/c/section-index
// What changed since: https://ds.interlace.tools/c/section-index#history
// Generated banner — keep it, the upgrade diff reads this version.

import { cn } from '@/lib/utils';

/**
 * SectionIndex — the numbered eyebrow: a zero-padded mono numeral in
 * the AAA brand orange beside an uppercase tracked label. The page's sections
 * become a legible sequence ("01 THE AGENDA … 04 THE PROOF"), telling
 * readers there is an order and where they stand in it.
 *
 * One reference law (BRAND_PHILOSOPHY §4): numbered section indices,
 * refracted through the terminal-decode voice — the numeral is
 * monospaced with tabular figures, the way a terminal counts, not a
 * display face. The numeral is the view's meaning-point accent in
 * `text-primary` — the 7:1 AAA-cleared brand orange, because at 14px

…70 more lines…

Registry JSON

The raw registry record — what the shadcn CLI fetches.