css3 黑白改变

<style>

    img:hover{
        -webkit-transition:-webkit-filter 1s ease-in;
        -moz-transition:-webkit-filter 1s ease-in;
        -webkit-filter: grayscale(100%); 
        -moz-filter: grayscale(100%); 
    }
</style>
<img src="http://b.hiphotos.baidu.com/album/w%3D310/sign=ecb207c8902397ddd6799e056983b216/b58f8c5494eef01fb3a326eae1fe9925bc317d6d.jpg">

可以打开后看看效果,