keyframes应用在animation上，animation应用在元素上。
<html>
<style type="text/css">
.div1 {
100px;height:100px;border:1px solid #000;position:relative;
animation : move 800ms ease-out infinite alternate;
}
@keyframes move {
from {top:0px;}
to {top:100px;}
}
</style>
<body>
<div class="div1">
</div>
</body>
</html>