div窗口随浏览器滚动一直居中
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style type="text/css">
.one{width:100%;height:3000px;text-align: center;}
.a1{display:inline-block;font-size: 16px;line-height: 35px;border:1px solid #ddd;border-radius: 3px;padding: 5px 10px;}
.two{text-align: center;padding:15px 30px;border:1px solid #ddd;display: none;position: fixed;top:50%;left:50%;margin-left: -100px;margin-top: -68px;}
p{margin-top: 20px;}
.a3{display:inline-block;font-size: 16px;line-height: 35px;border:1px solid #ddd;border-radius: 3px;padding: 5px 10px;background-color: #0088CC;color:#fff;margin-right: 30px;}
.a4{display:inline-block;font-size: 16px;line-height: 35px;border:1px solid #ddd;border-radius: 3px;padding: 5px 10px;}
</style>
</head>
<body>
<div class="one">
<a class="a1">快来点我呀</a><!--点击按钮-->
</div>
<!--弹窗-->
<div class="two">
<span class="a2">是否取消?</span>
<p><a class="a3">取消</a><a class="a4">确定</a></p>
</div>
<script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
<script type="text/javascript">
$(function(){
$(".a1").on("click",function(){
$(".two").css("display","inline-block");
});
});
</script>
</body>
</html>
