将一下代码放到css文件中

html {filter: grayscale(100%);-webkit-filter: grayscale(100%);-moz-filter: grayscale(100%);-ms-filter: grayscale(100%);-o-filter: grayscale(100%);filter: url(desaturate.svg#grayscale);filter:progid:DXImageTransform.Microsoft.BasicImage(grayscale=1);-webkit-filter: grayscale(1);}