:default
        
        
          
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      This feature is well established and works across many devices and browser versions. It’s been available across browsers since January 2020.
The :default CSS pseudo-class selects form elements that are the default in a group of related elements.
Try it
label,
input[type="submit"] {
  display: block;
  margin-top: 1em;
}
input:default {
  border: none;
  outline: 2px solid deeppink;
}
<form>
  <p>How did you find out about us?</p>
  <label
    ><input name="origin" type="radio" value="google" checked /> Google</label
  >
  <label><input name="origin" type="radio" value="facebook" /> Facebook</label>
  <p>Please agree to our terms:</p>
  <label
    ><input name="newsletter" type="checkbox" checked /> I want to subscribe to
    a personalized newsletter.</label
  >
  <label
    ><input name="privacy" type="checkbox" /> I have read and I agree to the
    Privacy Policy.</label
  >
  <input type="submit" value="Submit form" />
</form>
What this selector matches is defined in HTML Standard §4.16.3 Pseudo-classes — it may match the <button>, <input type="checkbox">, <input type="radio">, and <option> elements:
- A default option element is the first one with the selectedattribute, or the first enabled option in DOM order.multiple<select>s can have more than oneselectedoption, so all will match:default.
- <input type="checkbox">and- <input type="radio">match if they have the- checkedattribute.
- <button>matches if it is a- <form>'s default submission button: the first- <button>in DOM order that belongs to the form. This also applies to- <input>types that submit forms, like- imageor- submit.
Syntax
css
:default {
  /* ... */
}
Examples
>HTML
html
<fieldset>
  <legend>Favorite season</legend>
  <input type="radio" name="season" id="spring" value="spring" />
  <label for="spring">Spring</label>
  <input type="radio" name="season" id="summer" value="summer" checked />
  <label for="summer">Summer</label>
  <input type="radio" name="season" id="fall" value="fall" />
  <label for="fall">Fall</label>
  <input type="radio" name="season" id="winter" value="winter" />
  <label for="winter">Winter</label>
</fieldset>
CSS
css
input:default {
  box-shadow: 0 0 2px 1px coral;
}
input:default + label {
  color: coral;
}
Result
Specifications
| Specification | 
|---|
| HTML> # selector-default> | 
| Selectors Level 4> # default-pseudo> | 
Browser compatibility
Loading…
See also
- Web forms — Working with user data
- Styling web forms
- Related HTML elements: <button>,<input type="checkbox">,<input type="radio">, and<option>