animation
A propriedade CSS abreviada animation
, aplica uma animação entre estilos. É uma abreviação de animation-name
(en-US), animation-duration
(en-US), animation-timing-function
(en-US), animation-delay
, animation-iteration-count
(en-US), animation-direction
(en-US), animation-fill-mode
, e animation-play-state
(en-US).
Experimente
/* @keyframes duration | timing-function | delay |
iteration-count | direction | fill-mode | play-state | name */
animation: 3s ease-in 1s 2 reverse both paused slidein;
/* @keyframes name | duration | timing-function | delay */
animation: 3s linear 1s slidein;
/* @keyframes name | duration */
animation: slidein 3s;
A description of which properties are animatable (en-US) is available; it's worth noting that this description is also valid for CSS transitions (en-US).
Initial value | as each of the properties of the shorthand: |
---|---|
Aplica-se a | all elements, ::before and ::after pseudo-elements |
Inherited | não |
Computed value | as each of the properties of the shorthand:
|
Animation type | Not animatable |
Syntax
A propriedade animation
é especificada como uma ou mais animações, separadas por commas.
Cada animação individual é especificada como:
- zero or one occurrences of the following values:
- an optional name for the animation, which may be
none
, a<custom-ident>
(en-US), or a<string>
(en-US) - zero, one, or two
<time>
values
A ondem dos valores definidos dentro de cada animação é importante: o primeiro valor pode ser analisado com um <time>
é atribuido para o animation-duration
(en-US), and the second one is assigned to animation-delay
.
The order within each animation definition is also important for distinguishing animation-name
(en-US) values from other keywords. When parsed, keywords that are valid for properties other than animation-name
(en-US), and whose values were not found earlier in the shorthand, must be accepted for those properties rather than for animation-name
(en-US). Furthermore, when serialized, default values of other properties must be output in at least the cases necessary to distinguish an animation-name
(en-US) that could be a value of another property, and may be output in additional cases.
Values
<single-animation-iteration-count>
-
The number of times the animation is played. The value must be one of those available in
animation-iteration-count
(en-US). <single-animation-direction>
-
The direction in which the animation is played. The value must be one of those available in
animation-direction
(en-US). <single-animation-fill-mode>
-
Determines how styles should be applied to the animation's target before and after its execution. The value must be one of those available in
animation-fill-mode
. <single-animation-play-state>
-
Determines whether the animation is playing or not. The value must be one of those available in
animation-play-state
(en-US).
Formal syntax
animation =
<single-animation>#
<single-animation> =
<time> ||
<easing-function> ||
<time> ||
<single-animation-iteration-count> ||
<single-animation-direction> ||
<single-animation-fill-mode> ||
<single-animation-play-state> ||
[ none | <keyframes-name> ]
<easing-function> =
linear |
<linear-easing-function> |
<cubic-bezier-easing-function> |
<step-easing-function>
<single-animation-iteration-count> =
infinite |
<number [0,∞]>
<single-animation-direction> =
normal |
reverse |
alternate |
alternate-reverse
<single-animation-fill-mode> =
none |
forwards |
backwards |
both
<single-animation-play-state> =
running |
paused
<keyframes-name> =
<custom-ident> (en-US) |
<string> (en-US)
<linear-easing-function> =
linear( <linear-stop-list> )
<cubic-bezier-easing-function> =
ease |
ease-in |
ease-out |
ease-in-out |
cubic-bezier( <number [0,1]> , <number> , <number [0,1]> , <number> )
<step-easing-function> =
step-start |
step-end |
steps( <integer> (en-US) [, <step-position> ]? )
<linear-stop-list> =
[ <linear-stop> ]#
<step-position> =
jump-start |
jump-end |
jump-none |
jump-both |
start |
end
<linear-stop> =
<number> &&
<linear-stop-length>?
<linear-stop-length> =
<percentage> (en-US){1,2}
Examples
Cylon Eye
<div class="view_port">
<div class="polling_message">
Listening for dispatches
</div>
<div class="cylon_eye"></div>
</div>
.polling_message {
color: white;
float: left;
margin-right: 2%;
}
.view_port {
background-color: black;
height: 25px;
width: 100%;
overflow: hidden;
}
.cylon_eye {
background-color: red;
background-image: linear-gradient(to right,
rgba(0, 0, 0, .9) 25%,
rgba(0, 0, 0, .1) 50%,
rgba(0, 0, 0, .9) 75%);
color: white;
height: 100%;
width: 20%;
-webkit-animation: 4s linear 0s infinite alternate move_eye;
animation: 4s linear 0s infinite alternate move_eye;
}
@-webkit-keyframes move_eye { from { margin-left: -20%; } to { margin-left: 100%; } }
@keyframes move_eye { from { margin-left: -20%; } to { margin-left: 100%; } }
See Using CSS animations for additional examples.
Accessibility concerns
Blinking and flashing animation can be problematic for people with cognitive concerns such as Attention Deficit Hyperactivity Disorder (ADHD). Additionally, certain kinds of motion can be a trigger for Vestibular disorders, epilepsy, and migraine and Scotopic sensitivity.
Consider providing a mechanism for pausing or disabling animation, as well as using the Reduced Motion Media Query (en-US) to create a complimentary experience for users who have expressed a preference for no animated experiences.
- Designing Safer Web Animation For Motion Sensitivity · An A List Apart Article
- An Introduction to the Reduced Motion Media Query | CSS-Tricks
- Responsive Design for Motion | WebKit
- MDN Understanding WCAG, Guideline 2.2 explanations (en-US)
- Understanding Success Criterion 2.2.2 | W3C Understanding WCAG 2.0
Specifications
Specification | Status | Comment |
---|---|---|
CSS Animations Level 1 The definition of 'animation' in that specification. |
Rascunho atual | Initial definition. |
Compatibilidade com navegadores
BCD tables only load in the browser
Quantum CSS notes
- Gecko has a bug whereby when you animate an offscreen element onscreen but specify a delay, Gecko does not repaint on some platforms, e.g. Windows (bug 1383239). This has been fixed in Firefox's new parallel CSS engine (also known as Quantum CSS or Stylo, planned for release in Firefox 57).
- Another Gecko bug means that
<details>
elements can't be made open by default using theopen
attribute if they have an animation active on them (bug 1382124). Quantum CSS fixes this. - A further bug means that animations using em units are not affected by changes to the
font-size
on the animated element's parent, whereas they should be (bug 1254424). Quantum CSS fixes this.
See also
- Using CSS animations
- JavaScript
AnimationEvent
API