经常看到很多网页全部变成黑白，好奇研究了下
<html>
<title>heibai</title>
<head>
<style>
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;
<span style="white-space:pre"> </span>}
<span style="white-space:pre"> </span></style>
</head>
<body>
<img src="1.png" />
<br />
<img src="2.jpg" />
</body>
</html><html>
<title>heiba
