CSS top 顶部距离属性动画示例-实例在线编辑器(cainiaoplus.com)

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Example of CSS top Property Animation- 基础教程(cainiaoplus.com)</title>
<style>
.container{
	position: relative;
}
.animated {
	width: 150px;
	padding: 40px 0;
	position: absolute;
	top: 0;
	font: bold 46px sans-serif;
	text-align: center;
    background: #9acd32;	
    border: 1px solid #7da628;
    -webkit-animation: test 4s infinite; /* Chrome, Safari, Opera */
    animation: test 4s infinite;
}
/* Chrome, Safari, Opera */
@-webkit-keyframes test {
    50% {top: 300px;}
}
/* Standard syntax */
@keyframes test {
    50% {top: 300px;}
}
</style>
</head>
<body>
	<p><strong>Warning:</strong> CSS Animations do not work in Internet Explorer 9 and earlier versions.</p>
	<p><strong>Note:</strong> The top position of the following DIV element is animating from its initial value "0" to "300px", and back to the initial value "0" again up to infinite times.<p>
	<div class="container">
		<div class="animated">Box</div>
	</div>	
</body>
</html>