IOS系统下，键盘回收时<header>标签样式异常

分类：MUI

1.本次代码：

<!doctype html>  
<html>  

    <head>  
        <meta charset="UTF-8">  
        <title></title>  
        <meta name="viewport" content="width=device-width,initial-scale=1,minimum-scale=1,maximum-scale=1,user-scalable=no" />  
        <link href="css/mui.min.css" rel="stylesheet" />  
    </head>  

    <body>  
        <header class="mui-bar mui-bar-nav" style="background: red;">  
            <h1 class="mui-title">头部标题头部标题头部标题</h1>  
        </header>  
        <div class="mui-content">  
            <img src="images/logo.png" />  
            <div class="mui-input-group mui-card">  
                <div class="mui-input-row">  
                    <label><span class="iconfont icon-shouji1" style="font-size: 25px"></span></label>  
                    <input id="tel" type="tel" class="mui-input-clear" maxlength="11" placeholder="输入手机号码">  
                </div>  
                <div class="mui-input-row">  
                    <label><span class="iconfont icon-yanzhengma01" style="font-size: 25px"></span></label>  
                    <input id="verity_code" type="tel" placeholder="输入短信验证码" maxlength="6">  
                </div>  
            </div>  
            <div class="mui-content-padded">  
                <button type="button" class="mui-btn mui-btn-blue mui-btn-block" id="btn_login">登录</button>  
            </div>  
        </div>  
        <script src="js/mui.min.js"></script>  
        <script type="text/javascript">  
            mui.init()  
        </script>  
    </body>  

</html>

2.本次测试机：iphone4s （版本7.1.2） iphone5s(版本9.3.2) iphone6(版本9.3.2)

3.重现步骤:
3.1 页面内容的高度超过，键盘弹出的高度，如附件图1