frontend-syntax-css-has-selector
Installation
SKILL.md
Frontend Syntax : CSS :has() Relational Selector
Authoritative reference for the relational pseudo-class. Replaces JS-driven parent-state classes with native CSS while avoiding the well-known performance trap.
Quick Reference
Baseline status
| Attribute | Value | Source |
|---|---|---|
| Baseline Newly Available | December 2023 | MDN : :has() (verified 2026-05-19) |
| Baseline Widely Available | 2026 (30-month rule, around mid-2026) | [[frontend-core-web-standards-baseline]] |
Per evergreen-2026, :has() no longer requires a gate by default in 2026; legacy code paths that still target Newly-tier browsers SHOULD gate with @supports selector(:has(*)).