Facebook feed preloader animation

animation.css

.feed{
	-webkit-animation-duration: 1s;
	-webkit-animation-fill-mode: forwards;
	-webkit-animation-iteration-count: infinite;
	-webkit-animation-name: placeHolderShimmer;
	-webkit-animation-timing-function: linear;
	background: #f6f7f8;
	background-image: -webkit-linear-gradient(left, #f6f7f8 0%, #edeef1 20%, #f6f7f8 40%, #f6f7f8 100%);
	background-image: linear-gradient(left, #f6f7f8 0%, #edeef1 20%, #f6f7f8 40%, #f6f7f8 100%);
	background-repeat: no-repeat;
	background-size: 800px 104px;
	height: 104px;
	position: relative;
}