CSS Selectors

Pseudo-classes :checked

The :checked pseudo-class represents input elements(only for checkboxes or radio buttons) that are in an enabled state.

Syntax

:checked{ properties }

Example

[style.css]

 input:checked + label{
   font-weight: bold;
 }

[index.html]

<body>
<form>
  <input type="radio" id="m" name="gender" value="male">
  <label for="m">male</label>
  <input type="radio" id="f" name="gender" value="female">
  <label for="f">female</label>
</form>
</body>

CSS defines the :checked pseudo-class in 6.6.4.2. The :checked pseudo-class.