CSS Transitions

By  on  

There are two ways to create animations with pure CSS:  CSS animations and CSS transitions.  CSS transitions provide a simple method for animation one or multiple properties from one value to another.    CSS transitions do not require @keyframes -- simply provide the desired transition properties to a selector.  CSS transitions traditionally occur upon state changes, like :hover or :focus.

A Basic CSS Transitions

Let's create a basic CSS transition of opacity (a fade in and out):

/* from */
.myElement {
	opacity: 0.5;
	transition-property: opacity;
}

/* to */
.myElement:hover {
	opacity: 1;
}

In the example above, when the element is hovered over, its opacity animates from 50% opacity to 100% opacity.  When the mouse leaves the element, its opacity animates back down to 50%.

CSS Transition Properties

Outside of simply providing a CSS property to transition, there are a number of other helpful transition properties:

  • transition-property: one or more properties, or "all", to transition
  • transition-duration: amount of time the transition should take to complete (ex: 2s or 0.5s)
  • transition-delay: delay before starting the transition
  • transition-timing-function: traditional timing curve function for the transition

These transition properties allow complete control over the simple animation.  Here's a CSS transition example using all of the properties available:

/* from */
.myElement {
	color: #333;

	transition-property: color;
	transition-duration: 1s;
	transition-delay: .2s;
	transition-timing-function: linear;
}

/* to */
.myElement:focus {
	color: #999;
}

/* shorthand: property duration timingFunc delay */
.myElement {
	transition: all 2s linear 0.3s;
}

In most cases, the default duration, delay,and timing function wont need to be changed.

Transitioning Multiple Properties

Multiple transition properties should be separated by commas:

.myElement {
	/* padding-left, opacity, height, and color here */

	transition-property: padding-left, opacity, height, color;
	transition-duration: 1s, 2s, 3s, 4s;
}

The "all" keyword can also be used to signify all properties should be transformed.  Separate transitions may also be strung together in a shorthand syntax:

.myElement {
	transition: padding-left 1s, opacity 2s, height 3s, color: 4s;
}

The property value can get quite long, but the flexibility is quite nice!

Detecting Transition End with JavaScript

If you're looking to detect transition end with JavaScript, that's quite easy:

myElement.addEventListener("transitionend", function() {

	// Do something now that the transition has ended

}, true);

The transitionend event on the node will fire once the transition has completed.

CSS Transition Examples

My blog has featured a number of CSS transition examples:

Recent Features

  • By
    From Webcam to Animated GIF: the Secret Behind chat.meatspac.es!

    My team mate Edna Piranha is not only an awesome hacker; she's also a fantastic philosopher! Communication and online interactions is a subject that has kept her mind busy for a long time, and it has also resulted in a bunch of interesting experimental projects...

  • By
    Responsive Images: The Ultimate Guide

    Chances are that any Web designers using our Ghostlab browser testing app, which allows seamless testing across all devices simultaneously, will have worked with responsive design in some shape or form. And as today's websites and devices become ever more varied, a plethora of responsive images...

Incredible Demos

  • By
    Printing MooTools Accordion Items

    Sometimes we're presented with unforeseen problems when it comes to our JavaScript effects. In this case, I'm talking about printing jQuery and MooTools accordions. Each "closed" accordion content element has its height set to 0 which means it will be hidden when the...

  • By
    CSS Transforms

    CSS has become more and more powerful over the past few years and CSS transforms are a prime example. CSS transforms allow for sophisticated, powerful transformations of HTML elements.  One or more transformations can be applied to a given element and transforms can even be animated...

Discussion

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