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;
}

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-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

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 CSS Classes

Pseudo-elements can be combined with CSS 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 ::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 ::selectioncolorbackgroundcursor, and outline.

The following example makes the selected text red on a yellow background:

Example

::selection {
    color: red; 
    background: yellow;
}

All CSS Pseudo Elements

Selector Example Example description
::after p::after Insert something after the content of each <p> element
::before p::before Insert something before the content of each <p> element
::first-letter p::first-letter Selects the first letter of each <p> element
::first-line p::first-line Selects the first line of each <p> element
::selection p::selection Selects the portion of an element that is selected by a user

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