CSS Pseudo-Elements | CSS for Beginners - Class 6 PDF Download

What are Pseudo-Elements?

A CSS pseudo-element is used to style specified parts of an element.
For example, it can be used to:

• Style the first letter, or line, of an element
• Insert content before, or after, the content of an element

Syntax

The syntax of pseudo-elements:

selector::pseudo-element {

  property: value;

}

The ::first-line Pseudo-element

The ::first-line pseudo-element is used to add a special style to the first line of a text.
The following example formats the first line of the text in all <p> elements:
Example 

p::first-line {

  color: #ff0000;

  font-variant: small-caps;

}

Note: The ::first-line pseudo-element can only be applied to block-level elements.
The following properties apply to the ::first-line pseudo-element:

• font properties
• color properties
• background properties
• word-spacing
• letter-spacing
• text-decoration
• vertical-align
• text-transform
• line-height
• clear

Notice the double colon notation - ::first-line versus :first-line
The double colon replaced the single-colon notation for pseudo-elements in CSS3. This was an attempt from W3C to distinguish between pseudo-classes and pseudo-elements.
The single-colon syntax was used for both pseudo-classes and pseudo-elements in CSS2 and CSS1.
For backward compatibility, the single-colon syntax is acceptable for CSS2 and CSS1 pseudo-elements.

The ::first-letter Pseudo-element

The ::first-letter pseudo-element is used to add a special style to the first letter of a text.
The following example formats the first letter of the text in all <p> elements:
Example

p::first-letter {

  color: #ff0000;

  font-size: xx-large;

}

Note: The ::first-letter pseudo-element can only be applied to block-level elements.
The following properties apply to the ::first-letter pseudo- element:

• font properties
• color properties 
• background properties
• margin properties
• padding properties
• border properties
• text-decoration
• vertical-align (only if "float" is "none")
• text-transform
• line-height
• float
• clear

Pseudo-elements and HTML Classes

Pseudo-elements can be combined with HTML classes:  
Example

p.intro::first-letter {

  color: #ff0000;

  font-size: 200%;

}

The example above will display the first letter of paragraphs with class="intro", in red and in a larger size.

Multiple Pseudo-elements

Several pseudo-elements can also be combined.
In the following example, the first letter of a paragraph will be red, in an xx-large font size. The rest of the first line will be blue, and in small-caps. The rest of the paragraph will be the default font size and color:
Example

p::first-letter {

  color: #ff0000;

  font-size: xx-large;

}

p::first-line {

  color: #0000ff;

  font-variant: small-caps;

}

CSS - The ::before Pseudo-element

The ::before pseudo-element can be used to insert some content before the content of an element.
The following example inserts an image before the content of each <h1> element:
Example

h1::before {

  content: url(smiley.gif);

}

CSS - The ::after Pseudo-element

The ::after pseudo-element can be used to insert some content after the content of an element.
The following example inserts an image after the content of each <h1> element:
Example

h1::after {

  content: url(smiley.gif);

}

CSS - The ::marker Pseudo-element

The ::marker pseudo-element selects the markers of list items.
The following example styles the markers of list items:
Example

::marker {

  color: red;

  font-size: 23px;

}

CSS - The ::selection Pseudo-element

The ::selection pseudo-element matches the portion of an element that is selected by a user.
The following CSS properties can be applied to ::selection: color, background, cursor, and outline.
The following example makes the selected text red on a yellow background:
Example

::selection {

  color: red;

  background: yellow;

}

Test Yourself With Exercises

Exercise:
Set the background-color to red, of the first line of the paragraph.
<style>

____ {

  background-color: red;

}

</style>

<body>

<p class="intro">

In my younger and more vulnerable years

my father gave me some advice that I've

been turning over in my mind ever since.

'Whenever you feel like criticizing anyone,' he told me,

'just remember that all the people in this world

haven't had the advantages that you've had.'

</p>

</body>

<style>

.intro::first-line {

  background-color: red;

}

</style>

<body>

<p class="intro">

In my younger and more vulnerable years

my father gave me some advice that I've

been turning over in my mind ever since.

'Whenever you feel like criticizing anyone,' he told me,

'just remember that all the people in this world

haven't had the advantages that you've had.'

</p>

</body>

All CSS Pseudo Elements

All CSS Pseudo Classes