JavaScript clicks to make the entire page gray (can be used as an exit effect). _javascript skills

Click to make the entire page gray (can be used to exit).
Note:
nbsp;html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
must be added to the header of the page, otherwise the effect cannot be achieved

Safe exit
<script> <BR><!-- <BR>function log_out() <BR>{ <BR> ht = document.getElementsByTagName("html"); <BR> ht[0].style.filter = "progid:DXImageTransform.Microsoft.BasicImage(grayscale=1)"; <BR> if (confirm('你确定要退出管理？')) <BR> { <BR> window.location.href="Logout.asp"; <BR> } <BR> else <BR> { <BR> ht[0].style.filter = ""; <BR> return false; <BR> } <BR>} <BR>--> <BR></script>