CSS :optional

By  on  

A decade ago HTML and CSS added the ability to, at least signal, validation of form fields. The required attribute helped inform users which fields were required, while pattern allowed developers to provide a regular expression to match against an <input>'s value. Targeting required fields and validation values with just CSS and HTML was very useful.

Did you know that CSS provides :optional to allow you to style form elements that aren't required?

input:optional, select:optional, textarea:optional {
  border: 1px solid #eee;
}

[required] {
  border: 1px solid red;
}

In a sense, it feels like :optional represents :not([required]), but :optional is limited to just form fields.

Recent Features

  • By
    fetch API

    One of the worst kept secrets about AJAX on the web is that the underlying API for it, XMLHttpRequest, wasn't really made for what we've been using it for.  We've done well to create elegant APIs around XHR but we know we can do better.  Our effort to...

  • By
    Responsive and Infinitely Scalable JS Animations

    Back in late 2012 it was not easy to find open source projects using requestAnimationFrame() - this is the hook that allows Javascript code to synchronize with a web browser's native paint loop. Animations using this method can run at 60 fps and deliver fantastic...

Incredible Demos

Discussion

  1. It’s probably more like :not(:required), right?

Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!