:optional - CSS | MDN (original) (raw)
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The :optional
CSS pseudo-class represents any , , or element that does not have the required attribute set on it.
Try it
label {
display: block;
margin-top: 1em;
}
.req {
color: red;
}
*:optional {
background-color: palegreen;
}
<form>
<label for="name">Name: <span class="req">*</span></label>
<input id="name" name="name" type="text" required />
<label for="birth">Date of Birth:</label>
<input id="birth" name="birth" type="date" />
<label for="origin"
>How did you find out about us? <span class="req">*</span></label
>
<select id="origin" name="origin" required>
<option>Google</option>
<option>Facebook</option>
<option>Advertisement</option>
</select>
<p><span class="req">*</span> - Required field</p>
</form>
This pseudo-class is useful for styling fields that are not required to submit a form.
**Note:**The :required pseudo-class selects required form fields.
Syntax
Accessibility
If a form contains optional s, required inputs should be indicated using the required attribute. This will ensure that people navigating with the aid of assistive technology such as a screen reader will be able to understand which inputs need valid content to ensure a successful form submission.
Required inputs should also be indicated visually, using a treatment that does not rely solely on color to convey meaning. Typically, descriptive text and/or an icon are used.
- MDN Understanding WCAG, Guideline 3.3 explanations
- Understanding Success Criterion 3.3.2 | W3C Understanding WCAG 2.0
Examples
The optional field has a purple border
HTML
<form>
<div class="field">
<label for="url_input">Enter a URL:</label>
<input type="url" id="url_input" />
</div>
<div class="field">
<label for="email_input">Enter an email address:</label>
<input type="email" id="email_input" required />
</div>
</form>
CSS
label {
display: block;
margin: 1px;
padding: 1px;
}
.field {
margin: 1px;
padding: 1px;
}
input:optional {
border-color: rebeccapurple;
border-width: 3px;
}
Result
Specifications
Specification |
---|
HTML # selector-optional |
Selectors Level 4 # optional-pseudo |
Browser compatibility
See also
- Other validation-related pseudo-classes: :required, :invalid, :valid
- Form data validation