CSS animations

The animations CSS module lets you animate the values of CSS properties, such as background-position and transform, over time by using keyframes. Each keyframe describes how the animated element should render at a given time during the animation sequence. You can use the properties in the animations module to control the duration, number of repetitions, delayed start, and other aspects of an animation.

Animations in action

To view the animation in the box below, click the checkbox 'Play the animation' or hover the cursor over the box. When the animating is active, the cloud at the top changes shape, snowflakes fall, and the snow level at the bottom rises. To pause the animation, uncheck the checkbox or move your cursor away from the box.

This sample animation uses animation-iteration-count to make the flakes fall repeatedly, animation-direction to make the cloud move back and forth, animation-fill-mode to raise the snow level in response to the cloud movement, and animation-play-state to pause the animation. To see the code for this animation, view the source on Github.

Reference

Properties

At-rules

Functions

Events

All animations, even those with 0 seconds duration, throw animation events.

Interfaces

Guides

Using CSS animations

Step-by-step tutorial on how to create animations using CSS. This article describes the animation-related CSS properties and at-rule and how they interact with each other.

CSS animations tips and tricks

Tips and tricks to help you get the most out of CSS animations.

Specifications

Specification
CSS Animations Level 2
CSS Animations Level 1

See also