CSS Pseudo-classes

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CSS

Pseudo-classes

What are Pseudo-classes?

A pseudo-class is used to define a special state
of an element.

For example, it can be used to:

  • Style an element when a user mouses over it
  • Style visited and unvisited links differently
  • Style an element when it gets focus

Mouse Over Me

Syntax

The syntax of pseudo-classes:

selector:pseudo-class {
  property: value;
}

Anchor Pseudo-classes

Links can be displayed in different ways:

Example

/* unvisited link */
a:link {
  color: #FF0000;
}

/* visited
link */
a:visited {
  color: #00FF00;
}

/* mouse over link */
a:hover {
  color: #FF00FF;
}

/* selected link */
a:active {
  color: #0000FF;
}

Try it Yourself »

Note: a:hover MUST come after a:link and
a:visited in the CSS definition in order to be effective! a:active MUST come after
a:hover in the CSS definition in order to be effective!
Pseudo-class names are not case-sensitive.

Pseudo-classes and HTML Classes

Pseudo-classes can be combined with HTML classes:

When you hover over the link in the example, it will change color:

Hover on <div>

An example of using the :hover pseudo-class on a <div> element:

Simple Tooltip Hover

Hover over a <div> element to show a <p> element (like a tooltip):

Hover over me to show the <p> element.

Tada! Here I am!

Example

p {
  display: none;
 
background-color: yellow;
  padding: 20px;
}

div:hover p {
  display: block;
}

Try it Yourself »

CSS – The :first-child Pseudo-class

The :first-child pseudo-class matches a specified element that is the first child of another element.

Match the first <p> element

In the following example, the selector matches any <p> element that is the first child of any element:

Match the first <i> element in all <p> elements

In the following example, the selector matches the first <i> element in all <p> elements:

Example

p i:first-child
{
 
color: blue;
}

Try it Yourself »

Match all <i> elements in all first child <p> elements

In the following example, the selector matches all <i> elements in <p> elements that are the first child of another element:

Example

p:first-child i
{
  color: blue;
}

Try it Yourself »

CSS – The :lang Pseudo-class

The :lang pseudo-class allows you to define special rules for different languages.

In the example below, :lang defines the quotation marks for <q> elements with lang=”no”:

Example

<html>
<head>
<style>
q:lang(no) {
  quotes: “~” “~”;
}
</style>
</head>
<body>

<p>Some text <q lang=”no”>A quote in a paragraph</q>
Some text.</p>

</body>
</html>

Try it Yourself »

More Examples

Add different styles to hyperlinks
This example demonstrates how to add other styles to hyperlinks.

Use of :focus
This example demonstrates how to use the :focus pseudo-class.

Test Yourself With Exercises

Exercise:

Set the background-color to red, when you mouse over a link.

<style>
 {
  background-color: red;
}
</style>

<body>

<h1>This is a header.</h1>
<p>This is a paragraph.</p>
<a href="https://w3schools.com">This is a link.</a>

</body>

Start the Exercise

All CSS Pseudo Classes

Selector
Example
Example description

:active
a:active
Selects the active link

:checked
input:checked
Selects every checked <input> element

:disabled
input:disabled
Selects every disabled <input> element

:empty
p:empty
Selects every <p> element that has no children

:enabled
input:enabled
Selects every enabled <input> element

:first-child
p:first-child
Selects every <p> elements that is the first child of its parent

:first-of-type
p:first-of-type
Selects every <p> element that is the first <p> element of its parent

:focus
input:focus
Selects the <input> element that has focus

:hover
a:hover
Selects links on mouse over

:in-range
input:in-range
Selects <input> elements with a value within a specified range

:invalid
input:invalid
Selects all <input> elements with an invalid value

:lang(language)
p:lang(it)
Selects every <p> element with a lang attribute value starting with “it”

:last-child
p:last-child
Selects every <p> elements that is the last child of its parent

:last-of-type
p:last-of-type
Selects every <p> element that is the last <p> element of its parent

:link
a:link
Selects all unvisited links

:not(selector)
:not(p)
Selects every element that is not a <p> element

:nth-child(n)
p:nth-child(2)
Selects every <p> element that is the second child of its parent

:nth-last-child(n)
p:nth-last-child(2)
Selects every <p> element that is the second child of its parent, counting from the last child

:nth-last-of-type(n)
p:nth-last-of-type(2)
Selects every <p> element that is the second <p> element of its parent, counting from the last child

:nth-of-type(n)
p:nth-of-type(2)
Selects every <p> element that is the second <p> element of its parent

:only-of-type
p:only-of-type
Selects every <p> element that is the only <p> element of its parent

:only-child
p:only-child
Selects every <p> element that is the only child of its parent

:optional
input:optional
Selects <input> elements with no “required” attribute

:out-of-range
input:out-of-range
Selects <input> elements with a value outside a specified range

:read-only
input:read-only
Selects <input> elements with a “readonly” attribute specified

:read-write
input:read-write
Selects <input> elements with no “readonly” attribute

:required
input:required
Selects <input> elements with a “required” attribute specified

:root
root
Selects the document’s root element

:target
#news:target
Selects the current active #news element (clicked on a URL containing that anchor name)

:valid
input:valid
Selects all <input> elements with a valid value

:visited
a:visited
Selects all visited links

All CSS Pseudo Elements

Selector
Example
Example description

::after
p::after
Insert content after every <p> element

::before
p::before
Insert content before every <p> element

::first-letter
p::first-letter
Selects the first letter of every <p> element

::first-line
p::first-line
Selects the first line of every <p> element

::selection
p::selection
Selects the portion of an element that is selected by a user

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