The class attribute assigns one or more classnames to the <summary> tag.
Classnames are defined in a stylesheet or in a local <style> element.
Classes, i.e. classnames, are used to style elements.
A class attribute styling a <summary> element.
You sold 125 shares of MSFT at 11:29 AM
You bought 200 shares of GOOG at 11:26 AM
<style>
.summary {
background: #edf2ff; outline: none;
padding: 15px; border-radius: 5px;
text-transform: uppercase;
}
</style>
<details>
<summary class="summary">Order 4A801</summary>
<p>You sold 125 shares of MSFT at 11:29 AM</p>
<p>You bought 200 shares of GOOG at 11:26 AM</p>
</details>
Classes (i.e. classnames) are used for styling the summary element.
Multiple classnames are separated by a space.
JavaScript uses classes to access elements by classname.
Tip: class is a global attribute that can be applied to any HTML element.
<summary class="classnames">
| Value | Description |
|---|---|
| classnames | One or more space-separated class names. |
A class attribute styling a <summary> element.
Clicking the button toggles a classname that changes the background and text colors.
You sold 125 shares of MSFT at 11:29 AM
You bought 200 shares of GOOG at 11:26 AM
<style>
.summary-light {
background: #edf2ff; outline: none;
padding: 15px; border-radius: 5px;
text-transform: uppercase;
}
.summary-dark { background: #3630a3; color: white; }
</style>
<details>
<summary id="mysummary" class="summary-light">Order 4A801</summary>
<p>You sold 125 shares of MSFT at 11:29 AM</p>
<p>You bought 200 shares of GOOG at 11:26 AM</p>
</details>
<br />
<button onclick="toggle();">Toggle class</button>
<script>
let toggle = () => {
let element = document.getElementById("mysummary");
element.classList.toggle("summary-dark");
}
</script>
Two CSS classes are defined in the <style> element.
The class attribute in <summary> assigns one classname.
Repeatedly clicking the button toggles the second class, changing the background and text color of the <summary>.
Here is when class support started for each browser:
 Chrome
|
12.0 | Jun 2011 |
 Firefox
|
48.0 | Aug 2016 |
 IE/Edge
|
Not supported | |
 Opera
|
15.0 | May 2013 |
 Safari
|
6.0 | Jul 2012 |
Back to <summary>
