Demo Page

CSS3 Transitions Using :disabled

Below is a set of radio buttons. If you select the final one, the text box will become active by toggling the disabled attribute. The background color of the text box animates using CSS3 transitions.

Turtles
Muppets
Sasquatches
Something Else:

When the disabled attribute is added or removed, the :disabled pseudo-class takes effect, animating the background color of the text box. The animation of the color is pure CSS.