Covering the Implication and Basics of CSS Animation

Over the past few months, I’ve been embracing progressive enhancement on a new(er) level. I’ve been using CSS3 to make my life easier, leaving other browsers in the dust with the extra touches. I’ve lost all interest in making sure a design looks equally sophisticated in substandard browsers, and instead opted to leave that last column in my table left aligned instead of making the table a bit easier to read with right justification.

Of course I still support IE, and I don’t want to bring that up for debate at this time. That poor horse has been long gone for quite a while, so we can all put our sticks down for a bit. I have, however, taken a more aggressive personal stance in my lack of attention to detail when it comes to that browser family.

A tweet by Jeffrey Zeldman really got me hooked to the prospect of further adoption of CSS3:

When all browsers except IE support CSS3, it will test the limits of progressive enhancement as a design philosophy.

With my further embrace of and focus on CSS3 came an increased interest in other bleeding edge techniques in Web design, primarily CSS animation.

Does CSS animation belong?

One of the ways in which I’ve been trying to raise the overall comprehensiveness of my projects is incorporating CSS animation where it may enhance the experience of a particular design. Animation in CSS has, from time to time, been a hot topic in Web design. Does animation belong in CSS? Does it constitute behavioral modification to the document, and therefore find its proper place through JavaScript? Is animation technically behavior?

Trying to classify the true placement of animation has proven to be a personal challenge to me. I can see both sides of the argument. I agree that animation can be correctly implemented through JavaScript, as has been done for some time. On the other side of my personal coin, I see that animation is more of a visual stimulus as opposed to direct behavioral change (e.g. updating the DOM with data received via AJAX).

The basics of CSS animation

As with all new technologies, you should take a minute to familiarize yourself with implementation as well as implication to make a more educated (and therefore accurate) decision to (not) use it.

The WebKit team provided a very nice write up upon the release of a nightly build that supports CSS animation. In the post, an overview of animation with CSS is provided, as well as a bit of documentation and example.

The WebKit implementation of CSS animation has a bit of a learning curve, but once you decipher how it works, it’s quite elegant (in my opinion). Applying a CSS animation comes in two steps. You’ll first designate your style as you would normally, defining any properties you’d like, with the addition of something new: -webkit-transition.

-webkit-transition is actually shorthand for three transition properties:

  • transition-property: The property to which the animation will be applied
  • transition-duration: The length of time the transition will last
  • transition-timing-function: Possibly better explained as the easing method you’d like to use

With these three properties, you’re provided a set of tools that can directly affect the richness of your designs, bringing the level of interaction up a notch or two. To make things even more elaborate, the WebKit team has also included support for comma delimited transition declarations, allowing you to animate multiple values using a single property declaration.

A finished implementation of WebKit CSS animation may look something like this:

div.message a.dismiss {
  -webkit-transition:opacity 0.3s ease-in-out;

div.message a.dismiss:hover {

If you’re using a recent build of WebKit that supports CSS animation, check out the example.

CSS animation can have dramatic affect on your designs, especially in Web application enahcements. Jonathan Snook recently published a screencast outlining his use of CSS animations while playing with Titanium, a platform I’m actively researching as well.

Jonathan’s use of CSS animation in his screencast really brings its potential to the surface. With animations such as the combination of scale and opacity to achieve stellar effects really helps to make CSS animations shine.

What should control animation?

Truly classifying CSS animation has been a personal challenge for me as a designer; what are your thoughts? Do you feel that animation belongs in the realm of style or behavior? Do you feel animation is something else entirely? Now that an option beyond JavaScript has surfaced, did that change your opinion? Do you see animation in CSS being continually adopted on a more consistent level when it comes to adding ‘that little something extra’ for those using an applicable browser?