CSS :focus Selector

Select and style an input field when it gets focus:

input:focus {
background-color: yellow;
}

More "Try it Yourself" examples below.

Definition and Usage

The :focus selector is used to select the element that has focus.

Tip: The :focus selector is allowed on elements that accept keyboard events or other user inputs.

Version:	CSS2

The numbers in the table specifies the first browser version that fully supports the selector.

Selector
:focus	4.0	8.0	2.0	3.1	9.6

:focus {
css declarations;
} Demo

When an <input type="text"> gets focus, gradually change the width from 100px to 250px:

input[type=text] {
width: 100px;
transition: ease-in-out, width .35s ease-in-out;
}

input[type=text]:focus {
width: 250px;
}