# Spec: Forms (Layer 04)

File: `src/layers/04-forms.css`

## Purpose

Form element styling. Inputs, selects, textareas, buttons, checkboxes, radios, fieldsets, labels. Accessible by default.

## Scope

### In scope
- `button`, `input[type="button"]`, `input[type="submit"]`, `input[type="reset"]`
- `input[type="text|email|password|number|search|url|tel|date|time|datetime-local"]`
- `select`, `textarea`
- `fieldset`, `legend`, `label`
- `input[type="checkbox"]`, `input[type="radio"]`
- `progress`, `meter`
- `:focus-visible` ring styling
- `aria-invalid`, `aria-busy` states
- `[disabled]` styling

### Out of scope
- Form layout/grid (→ layouts layer)
- Custom form components built with data-attributes (→ data-attributes layer)

## Constraints

- References only semantic aliases from `01-tokens.css`
- All interactive elements must have visible focus indicators
- Respects `prefers-color-scheme` and `prefers-contrast`