<html>
<head>
<title>Title</title>
<style>
.bannerbox {
width:100%;
position:relative;
overflow:hidden;
height:200px;
}
.banner {
width:3000px; /*图片宽度*/
position:absolute;
left:50%;
margin-left:-1500px; /*图片宽度的一半*/
}
</style>
</head>
<body>
<div class="bannerbox">
<div class="banner">
<img src="t1.jpg">
</div>
</div>
</body>
</html>