Tools

CSS and the cascade

Every rule that applies to an element, with layers, container queries and var() chains.

The Element tab#

Select an element and open the side panel. The Element tab shows its selector, size and box model, then every CSS rule that applies to it.

Matched rules#

Rules in cascade order, with overridden declarations struck through
Cascade layers, nesting, @scope and container queries resolved as the browser does
var() chains followed back to the value that won
Rules for pseudo-elements, and values inherited from ancestors, in their own sections
A collapsed section for rules that only apply in other states, such as :hover
Shadow DOM: rules from open shadow roots

Stylesheets served from another origin cannot be read yet; the panel tells you how many were skipped. Reading them, and a computed-values view you can copy, are coming at launch.