react项目，将下列代码粘贴到global 直接挂到 #root 上即可
filter: grayscale(100%);
-webkit-filter: grayscale(100%);
-moz-filter: grayscale(100%);
-ms-filter: grayscale(100%);
-o-filter: grayscale(100%);
filter: url(data:image/svg+xml;utf8,#grayscale);
filter: progid:DXImageTransform.Microsoft.BasicImage(grayscale=1);
-webkit-filter: grayscale(1`);`
