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<!-- animation container -->
<h2 class="animation-title">Frame by Frame Animation: #4 Transform (CSS + JavaScript for IE Fallback)</h2>
<div class="eye-animation__wrapper">
<!-- sprite container(we will move this one) -->
<div class="eye-animation"></div>
</div>
.animation-title {
font-family: sans-serif;
text-align: center;
}
.eye-animation {
// we move the HTML element inside its wrapper so we set the element's width accordingly
width: 1800%;
height: 100%;
background-image: url('https://s3-us-west-2.amazonaws.com/s.cdpn.io/123941/blinking-eye-sprite.svg');
background-size: 100%, 100%;
background-repeat: no-repeat;
// 'animation-timing-function' ensures users won’t see half of one frame and half of the following frame both at the same time
// we set the number of steps to 17 because we have 18 frames
animation-name: eye-fill;
animation-duration: 1.3s;
animation-timing-function: steps(17);
animation-iteration-count: infinite;
// we position the sprite so that left frame is visible
position: absolute;
left: 0;
top: 0;
// this is the wrapper around the HTML element being moved
&__wrapper {
// place it in the middle of the screen
margin: auto;
// show only one frame at a time, hide unnecesary parts of the moving HTML element
overflow: hidden;
// allow inner HTML element to be absolutely positioned
position: relative;
width: 300px;
height: 300px;
}
}
// move element from left to right
@keyframes eye-fill {
from {
transform: translateX(0);
}
to {
transform: translateX(-94.44444444%);
}
}
// fallback for IE
.ie {
.eye-animation {
// tell the browser to move the element into a separate compositing layer to improve performance
transform: translate3d(0, 0, 0);
animation-name: eye-fill-ie;
}
}
// move element from left to right
@keyframes eye-fill-ie {
from {
left: 0;
}
to {
left: -1700%;
}
}
// we check if browser is Internet Explorer and if yes then we apply special class which we use in SCSS
var isIE = /Edge\/\d./i.test(navigator.userAgent) || /trident/i.test(navigator.userAgent);
if (_this.isIE) {
$('html').addClass('ie');
}
Also see: Tab Triggers