CSS animation-fill-mode

By  on  

We're always super excited to get into CSS animations because, quite frankly, they're incredibly awesome.  One overlooked animation property, however, is the animation-fill-mode property.  This CSS property sets the state of the end animation when the animation is not running.  Here's a quick example:

@keyframes fadeIn{
	0% { opacity: 0 }
	100% { opacity: 1 }
}

.fadeIn {
	animation-name: fadeIn;
	animation-duration: 1s;
	animation-fill-mode: forwards;
}

In the case of my fadeIn animation, I want the element to stay at an opacity of 1 when the animation is complete.  If I don't set the value to forwards, the element would go back to an opacity of 0 after the animation runs.  In most cases, you'll likely want the the value of animation-fill-mode to be forwards, so don't forget to add it!

Recent Features

  • By
    5 Ways that CSS and JavaScript Interact That You May Not Know About

    CSS and JavaScript:  the lines seemingly get blurred by each browser release.  They have always done a very different job but in the end they are both front-end technologies so they need do need to work closely.  We have our .js files and our .css, but...

  • By
    An Interview with Eric Meyer

    Your early CSS books were instrumental in pushing my love for front end technologies. What was it about CSS that you fell in love with and drove you to write about it? At first blush, it was the simplicity of it as compared to the table-and-spacer...

Incredible Demos

  • By
    Event Delegation with MooTools

    Events play a huge role in JavaScript. I can't name one website I've created in the past two years that hasn't used JavaScript event handling on some level. Ask yourself: how often do I inject elements into the DOM and not add an...

  • By
    Duplicate the jQuery Homepage Tooltips

    The jQuery homepage has a pretty suave tooltip-like effect as seen below: The amount of jQuery required to duplicate this effect is next to nothing;  in fact, there's more CSS than there is jQuery code!  Let's explore how we can duplicate jQuery's tooltip effect. The HTML The overall...

Discussion

  1. MaxArt

    Indeed, animation-fill-mode defaults to “none”, which means no animation style is applied when the animation starts or ends. You could expect “forwards” to be the default one, but… nope.

    The other values are “backwards” and “both”. Cue to MDN page:
    https://developer.mozilla.org/en-US/docs/Web/CSS/animation-fill-mode

  2. tomByrer

    > You could expect “forwards” to be the default one, but… nope.

    This is why Max: http://www.w3.org/TR/css3-animations/

    > The keyframes specify the behavior of one cycle of the animation… If a 0% or “from” keyframe is not specified, then the user agent constructs a 0% keyframe using the computed values of the properties being animated. If a 100% or “to” keyframe is not specified, then the user agent constructs a 100% keyframe using the computed values of the properties being animated.
    > …by default an animation does not affect property values after the animation ends. The ‘animation-fill-mode’ property can override this behavior.

    So, it is assumed that the non-animated state is the ‘default’ resting state for the animation.

  3. This definitely helped me out a few times. I also like the “animation-direction” property, it can lead to interesting effects: http://cdpn.io/Kdslg

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