CSS参考手册
级联和继承 | Cascading & Inheritance
未设置 | unset
unset
CSS关键词当它从其父继承了继承值,而其初始值没有,则unset
重置属性。换句话说,它inherit
在第一种情况下就像initial
关键字,而在第二种情况下就像关键字一样。它可以应用于任何CSS属性,包括CSS简写all
。
示例
颜色
.foo {
color: blue;
}
.bar {
color: green;
}
p {
color: red;
}
.bar p {
color: unset;
}
<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>
结果:
边界
div {
border: 1px solid green;
}
p {
border: 1px solid red;
}
.bar p {
border-color: unset;
}
<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 has a black border (initial default, not inherited).</p>
</div>
结果:
规范
Specification |
Status |
Comment |
---|---|---|
CSS Cascading and Inheritance Level 4The definition of 'unset' in that specification. |
Working Draft |
No changes from Level 3. |
CSS Cascading and Inheritance Level 3The definition of 'unset' in that specification. |
Candidate Recommendation |
Initial definition. |
浏览器兼容性
Feature |
Chrome |
Firefox (Gecko) |
Internet Explorer |
Opera |
Safari |
---|---|---|---|---|---|
Basic support |
41 |
27 (27) |
Edge build 10565+ |
28 |
9.1 |
Feature |
Android |
Firefox Mobile (Gecko) |
IE Phone |
Opera Mobile |
Safari Mobile |
---|---|---|---|---|---|
Basic support |
No support |
27.0 (27) |
No support |
No support |
9.3 |
级联和继承 | Cascading & Inheritance相关
层叠样式表( Cascading Style Sheets )是一种用来表现 HTML 或 XML 等文件样式的计算机语言。CSS 不仅可以静态地修饰网页,还可以配合各种脚本语言动态地对网页各元素进行格式化。