The ::part
CSS pseudo-element represents any element within a shadow tree that has a matching part
attribute.
custom-element::part(foo) {
/* Styles to apply to the `foo` part */
}
Syntax
::part( <ident>+ )
Examples
HTML
<template id="tabbed-custom-element">
<style type="text/css">
*, ::before, ::after {
box-sizing: border-box;
padding: 1rem;
}
:host {
display: flex;
}
</style>
<div part="tab active">Tab 1</div>
<div part="tab">Tab 2</div>
<div part="tab">Tab 3</div>
</template>
<tabbed-custom-element></tabbed-custom-element>
CSS
tabbed-custom-element::part(tab) {
color: #0c0dcc;
border-bottom: transparent solid 2px;
}
tabbed-custom-element::part(tab):hover {
background-color: #0c0d19;
border-color: #0c0d33;
}
tabbed-custom-element::part(tab):hover:active {
background-color: #0c0d33;
}
tabbed-custom-element::part(tab):focus {
box-shadow:
0 0 0 1px #0a84ff inset,
0 0 0 1px #0a84ff,
0 0 0 4px rgba(10, 132, 255, 0.3);
}
tabbed-custom-element::part(active) {
color: #0060df;
border-color: #0a84ff !important;
}
JavaScript
let template = document.querySelector("#tabbed-custom-element");
globalThis.customElements.define(template.id, class extends HTMLElement {
constructor() {
super();
this.attachShadow({ mode: "open" });
this.shadowRoot.appendChild(template.content);
}
});
Result
Specifications
Specification | Status | Comment |
---|---|---|
Shadow PartsThe definition of '::part' in that specification. | Working Draft | Initial definition. |
Browser compatibility
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
::part
|
Chrome
Full support 73 |
Edge
Full support 79 |
Firefox Full support 72 Full support 72 No support 69 — 72 Disabled' From version 69 until version 72 (exclusive): this feature is behind the |
IE
No support No |
Opera
Full support 60 |
Safari
Full support 13.1 |
WebView Android
Full support 73 |
Chrome Android
Full support 73 |
Firefox Android
No support No |
Opera Android
Full support 52 |
Safari iOS
Full support 13.4 |
Samsung Internet Android
Full support 11.0 |
Legend
- Full support
- Full support
- No support
- No support
- User must explicitly enable this feature.'
- User must explicitly enable this feature.
See also
- The
part
attribute - Used to define parts which can be selected by the::part()
selector - The
exportparts
attribute - Used to transitively export shadow parts from a nested shadow tree into a containing light tree. - Explainer: CSS Shadow ::part and ::theme
::part() by Mozilla Contributors is licensed under CC-BY-SA 2.5.