Native Nesting

Acceptable Support Updated: Dec 17, 2025

The ability to nest one style rule inside of another.

Baseline:
Newly
Functional:
Supported
Usage:
Cross-Context

Native CSS nesting works as expected within shadow DOM when applied to non-:host elements. However, nesting within :host selectors has mixed browser support: Safari versions earlier than 18.1 have known issues, nesting states on :host (e.g., :hover) fails, and the featureless & does not reference :host.

Shadow DOM Related Issues

Allowing & after ::part()

Discussion has closed on allowing & after ::part()

Stable

Web Platform Tests for

Chrome 148: Passes
Edge 148: Passes
Firefox 150: Passes
Safari 26.5: Passes
WPT sources: host-nesting-001, host-nesting-002, host-nesting-003, host-nesting-004, host-nesting-005