<!DOCTYPE html>
<html lang="ch">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>错误</title>
    <style>
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            min-height: 100vh;
            display: flex;
            justify-content: center;
            align-items: center;
            background-color: #f5f5f5;
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Microsoft YaHei', sans-serif;
        }

        .error-container {
            width: 100%;
            max-width: 400px;
            padding: 40px;
            background: #ffffff;
            text-align: center;
        }

        .error-icon {
            font-size: 48px;
            color: #333;
            margin-bottom: 24px;
        }

        .error-message {
            color: #666;
            font-size: 14px;
            line-height: 1.8;
            margin-bottom: 40px;
            min-height: 40px;
        }

        .action-links {
            display: flex;
            flex-direction: column;
            gap: 12px;
        }

        .action-link {
            display: block;
            padding: 10px;
            color: #333;
            text-decoration: none;
            border-bottom: 1px solid #e0e0e0;
            font-size: 13px;
            transition: all 0.3s ease;
        }

        .action-link:hover {
            border-bottom-color: #333;
            background-color: #f9f9f9;
        }

        .action-link:last-child {
            border-bottom: none;
        }
    </style>
</head>
<body>
<div class="error-container">
    <div class="error-icon">⚠️</div>

    <div class="error-message">未登录</div>

    <div class="action-links">
        <a href="javascript:history.back()" class="action-link">← 返回上一页</a>
        <a href="/admin" class="action-link">→ 返回系统主页</a>
        <a href="/" class="action-link">→ 返回登录页</a>
    </div>
</div>
</body>
</html>
