微信扫码下载，H5引导页

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width,initial-scale=1,maximum-scale=1,minimum-scale=1,user-scalable=no">
    <script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>
    <link href="css/layout.css" rel="stylesheet" type="text/css" />
    <title>云油</title>
</head>
<style>
    * {
        padding: 0;
        margin: 0;
    }

    body {
         100%;
        height: 100%;
        background: #FFFFFF;
        opacity: 0.8;
    }
    
    .bg {
        display: none;
        position: fixed;
        left: 0;
        top: 0;
        right: 0;
        bottom: 0;
        z-index: 10;
        background: rgba(0, 0, 0, 0.9);
        text-align: end;
        overflow: hidden;
        padding: 1rem 5px 0 1rem;
    }
    
    .bg img {
         93%;
        height: auto;
    }
    .htbg {
        background: url(images/bg.png);
        background-repeat: no-repeat;
         100%;
        height: 100%;
        background-size: 100% 100%;
        background-attachment: fixed;
        position: absolute;
        /* 500px;
        height: 700px;
        background-size: 100% 100%;
        filter: progid:DXImageTransform.Microsoft.AlphaImageLoader(src='images/bg.png',sizingMethod='scale');*/
    }
</style>

<body>
    <!--https://img-blog.csdnimg.cn/20201216150438676.png-->
    <div class="app">
        <div class="bg"><img src="images/13.png" alt=""></div>
    </div>
    <div class="htbg">
        <div align="center">
            <a href="javascript:void(0)" id="downloadButton">
                点击下载APP
            </a>
        </div>
       
    </div>
    <!--<div>
        <img src="images/logo.png" />
    </div>-->
    <!--<div class="main">
        <div class="xiazai_1">
            APP
        </div>
        <a href="javascript:void(0)" id="downloadButton" class="dianjianzhuang">点击安装</a>
    </div>-->
    <script>
        window.onload = function() {
                      var button = document.getElementById("downloadButton");
                       button.style.visibility = "visible";
                         button.onclick = function() {
                           window.location="http://www.qdgaoshanyun.com:9731/yunyou/yunyou1.apk";
                         }
	        var fontSize = $(window).width() / 18.75; //屏幕的宽
	        $("html").css("font-size", fontSize + "px");
	        if (IsWeixinOrAlipay() == 13) {
	                $(".bg").css('display', 'block')
	            } else {
	                console.log(IsWeixinOrAlipay())
	            }
        }

        function IsWeixinOrAlipay() {
            var ua = window.navigator.userAgent.toLowerCase();
            //判断是不是微信
            if (ua.match(/MicroMessenger/i) == 'micromessenger') {
                return 13;
            }
            //判断是不是支付宝
            if (ua.match(/AlipayClient/i) == 'alipayclient') {
                return 12;
            }
            //哪个都不是
            return 0;
        }
    </script>
</body>

</html>
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