CSS技巧之国家公祭日

* {
       filter: grayscale(100%);
       -webkit-filter: grayscale(100%);
       -moz-filter:grayscale(100%);
       -ms-filter: grayscale(100%);
       -o-filter:grayscale(100%);
}

img {
       filter: grayscale(100%);
       -webkit-filter: grayscale(100%);
       -moz-filter:grayscale(100%);
       -ms-filter: grayscale(100%);
       -o-filter:grayscale(100%);
}