CSS shadow parts

The CSS shadow parts module defines the ::part() pseudo-element that can be set on a shadow host. Using this pseudo-element, you can enable shadow hosts to expose the selected element in the shadow tree to the outside page for styling purposes.

By default, elements in a shadow tree can be styled only within their respective shadow roots. The CSS shadow parts module enables including a part attribute on <template> descendants that make up the custom element, exposing the shadow tree node to external styling via the ::part() pseudo-element.

Reference

Selectors

HTML attributes

Definitions

Guides

CSS pseudo-elements

Alphabetical list of pseudo-elements defined by all the CSS specifications and WebVTT

Web components

Overview of the different APIs that enable creating reusable custom elements or web components.

Specifications

Specification
CSS Shadow Parts

See also