Foundation · stable · v1.0.0 · owner: Site system lead · contract 19 of 20 points (open: figma)
Reference
Source reference; not an executed check.
ground- --cotton
text- --ink
links- --link
Do and don't
2 positive / 2 negative authored documentation examples (2 each required); 1 reference (1 required); 0 failed. References and failures do not count; this is not behavior acceptance.
Do: Semantic section heading
Authored by base.tsRendered consumer example; not an executed correctness check. heading Isolated document follows the browser's colour and contrast preferences. The outer theme toolbar does not control this document.
Open example: Base styles · Do: Semantic section heading Use the full-page example to follow page links.
Do: Readable document text
Authored by base.tsRendered consumer example; not an executed correctness check. text Isolated document follows the browser's colour and contrast preferences. The outer theme toolbar does not control this document.
Open example: Base styles · Do: Readable document text Use the full-page example to follow page links.
Don't: A component selector placed in base CSS
Authored by base.tsRule illustration; not an executed check. base / base.elements-only
styles/core/base.css
.promo-tile { padding: var(--space-8); }Don't: A page-specific default for every heading
Authored by base.tsRule illustration; not an executed check. base / base.elements-only
styles/core/base.css
.campaign-page h2 { color: var(--madder); }Rules
| Rule | Why | Check |
|---|---|---|
| Base styles target elements (h1, p, a), not classes, except the shared field contexts. | Classes belong to elements; base is the default. | Automated: scripts/site/system/check.ts (ownership) |
API
No props.
Contract details
The full contract: identity, anatomy, variants, states, tokens, layout, motion, accessibility, content, tests
Identity
| Aspect | Value |
|---|---|
| Id | base |
| Layer | Foundations |
| Category | foundation |
| Owner | Site system lead |
| Status | stable |
| Version | 1.0.0 |
| Source | apps/showcase/site/system/foundations/base.ts (private repository; the contract and the render function are this one module) |
| Version | Date | Change |
|---|---|---|
| 1.0.0 | 2026-10-26 | Base styles as one module: its markup moved out of the page builder (scripts/site) into the system. |
Use when
- Loaded first in every bundle. Why: Elements build on one shared default.
Do not use when
- To style a specific element. Why: Element styles live in the element's own stylesheet.
Anatomy
| Part | What it is |
|---|---|
| site | styles/core/base.css, styles/site/base.css |
| apps | styles/{health-check,contact,tour,ja-display}/base.css |
Made of: nothing (a base element).
Used in: pages directly.
Variants
| Variant | When | Why |
|---|---|---|
| light and dark | Every page, following the reader's setting. | The same roles resolve to light or dark values, so no element chooses its own. |
States
| State | Rendered or not applicable |
|---|---|
| default | The specimen. |
| hover | Not applicable: A foundation is not interactive. |
| focus-visible | Not applicable: Not focusable. |
| active | Not applicable: Not interactive. |
| disabled | Not applicable: Nothing to disable. |
| loading | Not applicable: Values are built into the stylesheet. |
| empty | Not applicable: The build fails if a value is missing. |
| error | Not applicable: Unresolved values fail the brand gate, not the reader. |
| current | Not applicable: No current item. |
| visited | Not applicable: Not a link. |
| expanded | Not applicable: Does not open. |
Tokens
| Part | Token |
|---|---|
| body.background | --cotton |
| body.color | --ink |
| a.color | --link |
| :focus-visible | --focus |
Layout
| Aspect | Value |
|---|---|
| breakpoints | Required review at 390, 768, 1024 and 1440 px; execution is not implied by this declaration; columns stack under 768 px; the wrap keeps a 16 px gutter on phones. |
| wrapping | Text wraps; nothing scrolls sideways. |
| textExpansion | Japanese runs 20 to 40% longer; headings break between phrases (jaBreaks) and blocks grow downwards. |
Spacing and rhythm
| Aspect | Value |
|---|---|
| internal | Not applicable: a foundation has no box of its own. |
| external | Not applicable. |
| rhythm | Applies to every element that reads it. |
Motion
| Aspect | Value |
|---|---|
| None | A foundation does not move. |
Runtime and reuse
Render-only element; mount any registered child enhancements separately. Preserve required Site CSS, fonts, responsive and locale rules from nativeElement.
Accessibility passport
| Aspect | Value |
|---|---|
| role | Not rendered on the site; its specimen in the Library is a list |
| name | The foundation's name |
| keyboard | Not interactive. |
| focus | Not focusable. |
| screenReader | The specimen is a plain list of names and values. |
| contrast | Every text and ground pair in the palette is checked (check-brand). |
| target | Not a target. |
Content
| Slot | Length | Voice |
|---|---|---|
| document headings and paragraphs (consumer-owned) | Heading or page-template budgets; base CSS imposes no copy length | Use semantic headings and readable paragraphs. Base styles supply defaults, not permission to turn body copy into a visual heading. |
| link wording (consumer-owned) | The link element's declared budget | Name the destination or action in the words; the shared underline and focus treatment do not explain a vague label. |
Good: “What happens next (Heading's section title)” · “Book a conversation (Button's named destination)”
Bad: “OVERVIEW (Heading's rejected capitals label)” · “Click here (Button's rejected vague label)”
Japanese: The document or consuming element sets Japanese language and wording; base CSS supplies :lang(ja) line breaking, headings with zero letter spacing and non-italic emphasis. Keep token and code names unchanged. Recheck Japanese wrapping and preserve the native-review-pending notice; these defaults do not translate content or complete native review.
Icons and illustrations
None: this element uses no icon or illustration of its own.
Decisions and exceptions
- None.
Usage
376 owned-class occurrences in built pages plus metadata-token references in built CSS (measured by npm run site:system).
No application mechanism is declared.
Current check result: not assessed by this report. Declarations and source-file presence do not establish executed enforcement or accepted coverage.
Tests
| Aspect | Value |
|---|---|
| unit | tests/unit/site-system.test.ts: renders every do and don't example through the registry and checks the classes it owns |
| visual | Not yet: there are no screenshot baselines; the Library page is checked for sideways scroll at 1440 px by tests/site/system.spec.ts |
| a11y | tests/site/system.spec.ts: axe (0 serious or critical) on the element's Library page in light and dark |
| parity | scripts/site/system/check.ts: Library examples are rendered by the same render function the site imports |
Figma
not-yet: The Loom Site Figma library is the last stage of the plan; this element is not mapped yet.