CSS Pseudo-elements - Explained with Examples

Elevate styling finesse with CSS Pseudo-elements! A comprehensive guide with examples for crafting intricate design details and enhancing visual appeal effortlessly.

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;
}

All CSS Pseudo Elements

SelectorExampleExample description
::afterp::afterInsert something after the content of each <p> element
::beforep::beforeInsert something before the content of each <p> element
::first-letterp::first-letterSelects the first letter of each <p> element
::first-linep::first-lineSelects the first line of each <p> element
::marker::markerSelects the markers of list items
::selectionp::selectionSelects the portion of an element that is selected by a user

All CSS Pseudo Classes

SelectorExampleExample description
:activea:activeSelects the active link
:checkedinput:checkedSelects every checked <input> element
:disabledinput:disabledSelects every disabled <input> element
:emptyp:emptySelects every <p> element that has no children
:enabledinput:enabledSelects every enabled <input> element
:first-childp:first-childSelects every <p> elements that is the first child of its parent
:first-of-typep:first-of-typeSelects every <p> element that is the first <p> element of its parent
:focusinput:focusSelects the <input> element that has focus
:hovera:hoverSelects links on mouse over
:in-rangeinput:in-rangeSelects <input> elements with a value within a specified range
:invalidinput:invalidSelects 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-childp:last-childSelects every <p> elements that is the last child of its parent
:last-of-typep:last-of-typeSelects every <p> element that is the last <p> element of its parent
:linka:linkSelects 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-typep:only-of-typeSelects every <p> element that is the only <p> element of its parent
:only-childp:only-childSelects every <p> element that is the only child of its parent
:optionalinput:optionalSelects <input> elements with no "required" attribute
:out-of-rangeinput:out-of-rangeSelects <input> elements with a value outside a specified range
:read-onlyinput:read-onlySelects <input> elements with a "readonly" attribute specified
:read-writeinput:read-writeSelects <input> elements with no "readonly" attribute
:requiredinput:requiredSelects <input> elements with a "required" attribute specified
:rootrootSelects the document's root element
:target#news:targetSelects the current active #news element (clicked on a URL containing that anchor name)
:validinput:validSelects all <input> elements with a valid value
:visiteda:visitedSelects all visited links

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CSS Pseudo-elements - Explained with Examples
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