theme/admin.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Login</title>
    <style>
        html{
            width: 100%;
            height: 100%;
            overflow: hidden;
            font-style: sans-serif;
        }
        body{
            width: 100%;
            height: 100%;
            font-family: 'Open Sans',sans-serif;
            margin: 0;
            background-color: #4A374A;
        }
        #login{
            position: absolute;
            top: 50%;
            left:50%;
            margin: -150px 0 0 -150px;
            width: 300px;
            height: 300px;
        }
        #login h1{
            color: #fff;
            text-shadow:0 0 10px;
            letter-spacing: 1px;
            text-align: center;
        }
        h1{
            font-size: 2em;
            margin: 0.67em 0;
        }
        input{
            width: 278px;
            height: 18px;
            margin-bottom: 10px;
            outline: none;
            padding: 10px;
            font-size: 13px;
            color: #fff;
            text-shadow:1px 1px 1px;
            border-top: 1px solid #312E3D;
            border-left: 1px solid #312E3D;
            border-right: 1px solid #312E3D;
            border-bottom: 1px solid #56536A;
            border-radius: 4px;
            background-color: #2D2D3F;
        }
        .but{
            width: 300px;
            min-height: 20px;
            display: block;
            background-color: #4a77d4;
            border: 1px solid #3762bc;
            color: #fff;
            padding: 9px 14px;
            font-size: 15px;
            line-height: normal;
            border-radius: 5px;
            margin: 0;
        }
    </style>
</head>
<body>
<div id="login">
    <h1>Login</h1>
        <input type="text" required="required" id="pin" placeholder="用户名" name="u" />
        <button class="but" onclick="login()">登录</button>
</div>

<script>

    function login()
    {
        const userName = document.querySelector('#pin').value
        sessionStorage.setItem('pin',document.getElementById("pin").value);
        var xmlhttp = window.XMLHttpRequest ? new XMLHttpRequest() : new ActiveXObject("Microsoft.XMLHTTP");
        xmlhttp.onreadystatechange = function() {
            if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
                var results = xmlhttp.responseText
                console.log(results)
                switch (results) {
                    case "授权登录未确认":
                        break;
                    case "登录":
                        setTimeout(() => {
                            window.location.href = "/admin"
                        }, 1000);
                        break;
                    case "成功":
                        setTimeout(() => {
                            window.location.href = "/admin"
                        }, 1000);
                        break;
                    default:
                        break;
                }
            }
        }
        xmlhttp.open("POST","/api/login/admin", true);
        xmlhttp.setRequestHeader("Content-Type","application/x-www-form-urlencoded")
        xmlhttp.send("pin="+userName);
    }
</script>
</body>
</html>