<!DOCTYPE html>
<html>
<head>
<style>
img {
-webkit-filter: grayscale(100%); /* Chrome, Safari, Opera */
filter: grayscale(100%);
}
</style>
</head>
<body>
<p>Convert the image to grayscale:</p>
<img src="flowers.jpg" alt="" width="350" height="200">
<p><strong>Note:</strong> The filter property is not supported in Internet Explorer.</p>
</body>
</html>