Class selectors
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The CSS class selector matches elements based on the contents of their class
attribute.
css
/* All elements with class="spacious" */
.spacious {
margin: 2em;
}
/* All <li> elements with class="spacious" */
li.spacious {
margin: 2em;
}
/* All <li> elements with a class list that includes both "spacious" and "elegant" */
/* For example, class="elegant retro spacious" */
li.spacious.elegant {
margin: 2em;
}
Syntax
css
.class_name { style properties }
Note that this is equivalent to the following attribute selector:
css
[class~=class_name] { style properties }
The class_name
value must be a valid CSS identifier. HTML class
attributes which are not valid CSS identifiers must be escaped before they can be used in class selectors.
Examples
Valid class selectors
HTML
html
<p class="red">This paragraph has red text.</p>
<p class="red yellow-bg">
This paragraph has red text and a yellow background.
</p>
<p class="red fancy">This paragraph has red text and "fancy" styling.</p>
<p>This is just a regular paragraph.</p>
html
<!-- The next two paragraphs have class attributes
that contain characters which must be escaped in CSS -->
<p class="item?one">This paragraph has a pink background.</p>
<p class="123item">This paragraph has a yellow background.</p>
CSS
css
.red {
color: #f33;
}
.yellow-bg {
background: #ffa;
}
.fancy {
font-weight: bold;
text-shadow: 4px 4px 3px #77f;
}
css
/* In the next two rules, the class attributes must be escaped */
.item\?one {
background-color: pink;
}
.\00003123item {
background-color: yellow;
}
Result
Invalid class selectors
The class selectors in the following rules are not valid CSS identifiers, and will be ignored.
css
.item?one {
background-color: green;
}
.123item {
background-color: green;
}
Specifications
Specification |
---|
Selectors Level 4 # class-html |
Browser compatibility
Report problems with this compatibility data on GitHubdesktop | mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Class selector ( .className ) |
Legend
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- Full support
- Full support
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.