:root

概述

:root 这个 CSS 伪类匹配文档树的根元素。对于 HTML 来说，:root 表示 <html> 元素，除了优先级更高之外，与 html 选择器相同。

语法

:root

示例

在声明全局 CSS 变量时 :root 会很有用：

:root {
  --main-color: hotpink;
  --pane-padding: 5px 42px;
}

规范

Specification Status Comment
Selectors Level 4
:root		 Working Draft No change
Selectors Level 3
:root		 Recommendation Initial definition

浏览器兼容性

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!
Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support 1 (Yes) 1.0 (1.7 or earlier) 9 9.5 1.0
Feature Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support ? (Yes) ? ? ? ?
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