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
    Vibration API

    Many of the new APIs provided to us by browser vendors are more targeted toward the mobile user than the desktop user.  One of those simple APIs the Vibration API.  The Vibration API allows developers to direct the device, using JavaScript, to vibrate in...

  • By
    5 More HTML5 APIs You Didn’t Know Existed

    The HTML5 revolution has provided us some awesome JavaScript and HTML APIs.  Some are APIs we knew we've needed for years, others are cutting edge mobile and desktop helpers.  Regardless of API strength or purpose, anything to help us better do our job is a...

Incredible Demos

  • By
    Full Width Textareas

    Working with textarea widths can be painful if you want the textarea to span 100% width.  Why painful?  Because if the textarea's containing element has padding, your "width:100%" textarea will likely stretch outside of the parent container -- a frustrating prospect to say the least.  Luckily...

  • By
    jQuery UI DatePicker:  Disable Specified Days

    One project I'm currently working on requires jQuery. The project also features a datepicker for requesting a visit to their location. jQuery UI's DatePicker plugin was the natural choice and it does a really nice job. One challenge I encountered was the...

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!