页面变灰效果

body *{
    -webkit-filter: grayscale(100%); /* webkit */
    -moz-filter: grayscale(100%); /*firefox*/
    -ms-filter: grayscale(100%); /*ie9*/
    -o-filter: grayscale(100%); /*opera*/
    filter: grayscale(100%);
    filter:progid:DXImageTransform.Microsoft.BasicImage(grayscale=1); 
    filter:gray; /*ie9- */
}