做了CSS3的动画，但是无效

做了css3动画后，没有反应

不要有空格hover样式li:first-child img:hover

<style>
    @keyframes anima{
    from{transform:rotate(0deg)}
    to{transform:rotate(360deg)}
    }
    li:first-child img:hover{
    animation-name:anima;
    animation-duration:10s;
    animation-iteration-count:infinite
    }
</style>
<ul>
    <li>
        <img src="https://img1.baidu.com/it/u=2897436077,1965736138&fm=26&fmt=auto" />
    </li>
</ul>