Anchor position container queries
Anchor position container queries with the @container anchored(fallback: …) at-rule apply styles to an element based on the element's anchor position.
Browser support
| Feature | Desktop | Mobile | ||||
|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Safari | Chrome Android | Safari iOS | |
css.at-rules.container.anchor_position_queries Experimental | 143 | 143 | | | 143 | |
| CSS at-rule | ||||||
anchor position queries.fallback Experimental `fallback` feature | 143 | 143 | | | 143 | |
anchor position queries.fallback.any value Experimental `any` query value | 143 | 143 | | | 143 | |
| CSS property | ||||||
anchored Experimental | 143 | 143 | | | 143 | |
1+Supported (version) Not supported ※Has note Sub-feature descriptions sourced from MDN Web Docs (CC BY-SA 2.5)
Syntax
CSS
.tooltip {
position: absolute;
position-anchor: --trigger;
}
@container anchored(fallback: bottom) {
.tooltip::before { transform: rotate(180deg); }
}Live demo
Use cases
-
Browser-native behavior
Use Anchor position container queries to rely on the platform for behavior that would otherwise require extra code or CSS complexity.
-
Progressive enhancement
Enhance the experience where support exists while keeping a solid baseline elsewhere.
Cautions
- Check browser support and actual product need before adding a new platform feature widely.
- Keep feature usage understandable so future contributors know why it was chosen.
Accessibility
- New platform features should still preserve readable defaults and robust interaction patterns.
- Verify that enhancement paths do not leave unsupported environments with a broken experience.