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CSS :focus pseudo-class


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Definition

The :focus pseudo-class adds a special style to an element while the element has focus.

Examples

a:link {color: #FF0000}     /* unvisited link */
a:focus {color: #00FF00}  /* focused link */

Note: Pseudo-class names are not case-sensitive.

Note: Pseudo-classes can be also be combined with CSS classes: 

a.red:visited {color: #FF0000}
<a class="red" href="css_syntax.asp">CSS Syntax</a>

If the link in the example above has been visited, it will be displayed in red.


Try-It-Yourself Demos

Hyperlink: use of :focus (does not work in IE)
This example demonstrates how to use the :focus pseudo-class on a hyperlink.


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From http://www.w3schools.com (Copyright Refsnes Data)