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• 范例
• 规范
• 浏览器兼容性
• 另请参阅
• 相关话题

unset CSS keyword resets a property to its inherited value if the property naturally inherits from its parent, and to its initial value if not. In other words, it behaves like the inherit keyword in the first case, when the property is an inherited property , and like the initial keyword in the second case, when the property is a non-inherited property .

unset can be applied to any CSS property, including the CSS shorthand all .

范例

Color

HTML

<p>This text is red.</p>
<div class="foo">
  <p>This text is also red.</p>
</div>
<div class="bar">
  <p>This text is green (default inherited value).</p>
</div>
					

CSS

.foo {
  color: blue;
}
.bar {
  color: green;
}
p {
  color: red;
}
.bar p {
  color: unset;
}
					

结果

Border

HTML

<p>This text has a red border.</p>
<div>
  <p>This text has a red border.</p>
</div>
<div class="bar">
  <p>This text has a black border (initial default, not inherited).</p>
</div>
					

CSS

div {
  border: 1px solid green;
}
p {
  border: 1px solid red;
}
.bar p {
  border-color: unset;
}
					

结果

规范

规范	状态	注释
CSS Cascading and Inheritance Level 4 The definition of 'unset' in that specification.	候选推荐	No changes from Level 3.
CSS Cascading and Inheritance Level 3 The definition of 'unset' in that specification.	候选推荐	初始定义。

浏览器兼容性

The compatibility table on 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. 更新 GitHub 上的兼容性数据

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
unset	Chrome 完整支持 41	Edge 完整支持 13	Firefox 完整支持 27	IE 不支持 No	Opera 完整支持 28	Safari 完整支持 9.1	WebView Android 完整支持 41	Chrome Android 完整支持 41	Firefox Android 完整支持 27	Opera Android 完整支持 28	Safari iOS 完整支持 9.3	Samsung Internet Android 完整支持 4.0

图例

完整支持

完整支持

不支持

不支持

另请参阅

• 使用 initial to set a property to its initial value.
• 使用 revert to reset a property to the value established by the user-agent stylesheet (or by user styles, if any exist).
• 使用 inherit to make an element's property the same as its parent.
• all property lets you reset all properties to their initial, inherited, reverted, or unset state at once.

元数据

• 最后修改： Jul 16, 2020

相关话题

1. CSS
2. CSS 参考