:root {
            --primary-blue: #2563eb;
            --secondary-blue: #3b82f6;
            --accent-blue: #60a5fa;
            --dark-bg: #0f172a;
            --card-bg: #1e293b;
            --text-primary: #f8fafc;
            --text-secondary: #cbd5e1;
            --border-color: #334155;
            --success: #10b981;
            --warning: #f59e0b;
            --error: #ef4444;
        }

        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
            background: var(--dark-bg);
            color: var(--text-primary);
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            line-height: 1.6;
        }

        /* 顶部导航栏 */
        .header {
            background: var(--card-bg);
            border-bottom: 1px solid var(--border-color);
            padding: 1.5rem 2rem;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .logo {
            display: flex;
            align-items: center;
            gap: 12px;
            font-weight: 600;
            font-size: 1.5rem;
        }

        .logo-icon {
            color: var(--primary-blue);
            font-size: 1.8rem;
        }

        .nav-links {
            display: flex;
            gap: 2rem;
        }

        .nav-link {
            color: var(--text-secondary);
            text-decoration: none;
            font-weight: 500;
            transition: color 0.2s;
        }

        .nav-link:hover {
            color: var(--accent-blue);
        }

        /* 主要内容区域 */
        .main-content {
            flex: 1;
            display: flex;
            align-items: center;
            justify-content: center;
            padding: 3rem 2rem;
        }

        .error-container {
            max-width: 1200px;
            width: 100%;
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 4rem;
            align-items: center;
        }

        @media (max-width: 768px) {
            .error-container {
                grid-template-columns: 1fr;
                gap: 2rem;
            }
        }

        /* 错误代码区域 */
        .error-code-section {
            text-align: center;
        }

        .error-code {
            font-size: 12rem;
            font-weight: 700;
            color: var(--primary-blue);
            line-height: 1;
            margin-bottom: 1rem;
            position: relative;
        }

        .error-code::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 50%;
            transform: translateX(-50%);
            width: 120px;
            height: 4px;
            background: linear-gradient(90deg, var(--primary-blue), var(--accent-blue));
            border-radius: 2px;
        }

        .error-subtitle {
            font-size: 1.5rem;
            color: var(--text-secondary);
            margin-top: 1rem;
        }

        /* 信息面板 */
        .info-panel {
            background: var(--card-bg);
            border: 1px solid var(--border-color);
            border-radius: 12px;
            padding: 2.5rem;
            box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
        }

        .info-title {
            font-size: 1.8rem;
            margin-bottom: 1rem;
            color: var(--text-primary);
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .info-title i {
            color: var(--primary-blue);
        }

        .info-text {
            color: var(--text-secondary);
            margin-bottom: 2rem;
            font-size: 1.1rem;
        }

        /* 可能的原因列表 */
        .causes-list {
            margin-bottom: 2.5rem;
        }

        .causes-title {
            font-size: 1.2rem;
            margin-bottom: 1rem;
            color: var(--text-primary);
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .causes-title i {
            color: var(--warning);
        }

        .cause-item {
            display: flex;
            align-items: flex-start;
            gap: 12px;
            margin-bottom: 1rem;
            padding: 0.8rem;
            background: rgba(255, 255, 255, 0.03);
            border-radius: 8px;
            transition: background 0.2s;
        }

        .cause-item:hover {
            background: rgba(255, 255, 255, 0.05);
        }

        .cause-icon {
            color: var(--accent-blue);
            font-size: 1.2rem;
            margin-top: 2px;
        }

        .cause-text {
            color: var(--text-secondary);
            flex: 1;
        }

        /* 操作按钮 */
        .actions {
            display: flex;
            gap: 1rem;
            flex-wrap: wrap;
        }

        .action-btn {
            padding: 0.9rem 1.8rem;
            border-radius: 8px;
            font-weight: 500;
            font-size: 1rem;
            cursor: pointer;
            transition: all 0.2s;
            border: none;
            display: inline-flex;
            align-items: center;
            gap: 10px;
            text-decoration: none;
        }

        .action-btn.primary {
            background: var(--primary-blue);
            color: white;
        }

        .action-btn.primary:hover {
            background: var(--secondary-blue);
            transform: translateY(-2px);
            box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
        }

        .action-btn.secondary {
            background: rgba(255, 255, 255, 0.1);
            color: var(--text-primary);
            border: 1px solid var(--border-color);
        }

        .action-btn.secondary:hover {
            background: rgba(255, 255, 255, 0.15);
            transform: translateY(-2px);
        }

        .action-btn.outline {
            background: transparent;
            color: var(--primary-blue);
            border: 1px solid var(--primary-blue);
        }

        .action-btn.outline:hover {
            background: rgba(37, 99, 235, 0.1);
        }

        /* 系统状态指示器 */
        .system-status {
            display: flex;
            gap: 2rem;
            margin-top: 2.5rem;
            padding-top: 2rem;
            border-top: 1px solid var(--border-color);
        }

        .status-item {
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .status-dot {
            width: 10px;
            height: 10px;
            border-radius: 50%;
            background: var(--success);
        }

        .status-dot.warning {
            background: var(--warning);
        }

        .status-text {
            color: var(--text-secondary);
            font-size: 0.9rem;
        }

        /* 页脚 */
        .footer {
            background: var(--card-bg);
            border-top: 1px solid var(--border-color);
            padding: 2rem;
            text-align: center;
            color: var(--text-secondary);
        }

        .footer-links {
            display: flex;
            justify-content: center;
            gap: 2rem;
            margin-bottom: 1rem;
            flex-wrap: wrap;
        }

        .footer-link {
            color: var(--text-secondary);
            text-decoration: none;
            font-size: 0.9rem;
            transition: color 0.2s;
        }

        .footer-link:hover {
            color: var(--accent-blue);
        }

        .copyright {
            font-size: 0.85rem;
            opacity: 0.8;
        }

        /* 简约动画 */
        @keyframes fadeIn {
            from { opacity: 0; transform: translateY(10px); }
            to { opacity: 1; transform: translateY(0); }
        }

        .error-code-section, .info-panel {
            animation: fadeIn 0.6s ease-out forwards;
        }

        .info-panel {
            animation-delay: 0.2s;
        }

        /* 简约背景图案 */
        .bg-pattern {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-image: 
                radial-gradient(circle at 10% 20%, rgba(37, 99, 235, 0.05) 0%, transparent 20%),
                radial-gradient(circle at 90% 80%, rgba(59, 130, 246, 0.05) 0%, transparent 20%);
            z-index: -1;
        }

        /* 响应式调整 */
        @media (max-width: 768px) {
            .header {
                flex-direction: column;
                gap: 1rem;
                padding: 1rem;
            }
            
            .nav-links {
                gap: 1rem;
            }
            
            .error-code {
                font-size: 8rem;
            }
            
            .info-panel {
                padding: 1.5rem;
            }
            
            .actions {
                flex-direction: column;
            }
            
            .action-btn {
                justify-content: center;
            }
            
            .system-status {
                flex-direction: column;
                gap: 1rem;
            }
        }