Primitives (`tngCollapsible`)
Behavior-only primitive with explicit trigger/content wiring.
Open Enabled
Primitive content region. Use Enter/Space on the trigger button to toggle visibility.
Collapsible Demo
Compare headless primitive wiring and the component wrapper with the same open/disabled control flow.
Components (`tng-collapsible`)
Styled wrapper that forwards the same accessibility contract.
Closed Enabled
- Run lint and Vitest in affected projects.
- Validate demo pages in both tailwind and plain-css apps.
- Commit with component-scoped change set.