index.html

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<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Welcome</title>
    <style>
        div {
            width: 600px;
            margin: 15% auto auto auto;
            text-align: center;
            font-size: 20px;
            color: #555;
        }
    </style>
</head>

<body>
    <div>
        <p>欢迎来到 MY MALL</p>
        <p>本站仅用于测试，用测试数据模拟后台接口。</p>
        <p>
            页面将在
            <span id="second-clock"></span>
            秒后跳转到网站首页
        </p>
    </div>
    <script>          
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        function timeCount() {
            console.log('11');
            document.getElementById('second-clock').innerHTML=num;
            num=num-1;
            if (num!=-1) {
                i=setTimeout("timeCount()",1000);
            }else{
                window.location.href='dist/view/index.html';
            }
        }
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</body>

</html>