<html>
<head>
<title>alpha滤镜</title>
<style>
<!--
body{
background:url(bg1.jpg);
margin:20px;
}
img{
border:1px solid #d58000;
}
.alpha{
filter:alpha(opacity=50);
}
-->
</style>
</head>
<body>
<img src="building1.jpg" border="0">
<img src="building1.jpg" border="0" class="alpha">
</body>
</html>
