效果图：
代码如下：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>jquery点击弹出登陆窗口</title>
<link rel="stylesheet" type="text/css" href="./lanrenzhijia.css">
<script type="text/javascript" src="./jquery-1.8.0.min.js"></script>
<script>
jQuery(document).ready(function($) {
$('.theme-login').click(function(){
$('.theme-popover-mask').fadeIn(100);
$('.theme-popover').slideDown(200);
})
$('.theme-poptit .close').click(function(){
$('.theme-popover-mask').fadeOut(100);
$('.theme-popover').slideUp(200);
})
})
</script>
</head>
<body>
<div class="theme-buy">
<a class="btn btn-primary btn-large theme-login" href="javascript:;">点击查看效果</a>
</div>
<div class="theme-popover">
<div class="theme-poptit">
<a href="javascript:;" title="关闭" class="close">×</a>
<h3>登录 是一种态度</h3>
</div>
<div class="theme-popbod dform">
<form class="theme-signin" name="loginform" action="" method="post">
<ol>
<li><h4>你必须先登录！</h4></li>
<li><strong>用户名：</strong><input class="ipt" type="text" name="log" value="9958.pw" size="20" /></li>
<li><strong>密码：</strong><input class="ipt" type="password" name="pwd" value="***" size="20" /></li>
<li><input class="btn btn-primary" type="submit" name="submit" value=" 登 录 " /></li>
</ol>
</form>
</div>
</div>
<div class="theme-popover-mask"></div>
</body>
</html>
<style></style>
<script></script>