使用 CSS Filter網頁變成黑白

source: https://free.com.tw/css-filter-grayscale/

html {
-webkit-filter: grayscale(100%);
-moz-filter: grayscale(100%);
-ms-filter: grayscale(100%);
-o-filter: grayscale(100%);
filter: progid:DXImageTransform.Microsoft.BasicImage(grayscale=1);
_filter: none;
}