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

        body {
            font-family: "Inter", "Noto Sans TC", "Roboto Condensed", ui-sans-serif, system-ui, -apple-system, "Segoe UI", "PingFang TC", "Microsoft JhengHei", Arial, sans-serif;
            background: linear-gradient(145deg, #111827 0%, #1f2937 60%, #292217 100%);
            min-height: 100vh;
            display: flex;
            justify-content: center;
            align-items: center;
            padding: 20px;
        }

        .login-container {
            background: #fff;
            padding: 44px 40px;
            border-radius: 16px;
            box-shadow: 0 4px 8px rgba(0,0,0,0.06), 0 20px 60px rgba(0,0,0,0.18), 0 0 0 1px rgba(245,158,11,0.1);
            width: 100%;
            max-width: 400px;
            border-top: 3px solid #f59e0b;
        }

        .login-header {
            text-align: center;
            margin-bottom: 30px;
        }

        .login-header h1 {
            color: #111827;
            font-size: 26px;
            font-weight: 700;
            margin-bottom: 8px;
            letter-spacing: 1px;
        }

        .login-header p {
            color: #6b7280;
            font-size: 13px;
            letter-spacing: 0.5px;
        }

        .login-form {
            display: flex;
            flex-direction: column;
            gap: 20px;
        }

        .form-group {
            display: flex;
            flex-direction: column;
            gap: 8px;
        }

        .form-group label {
            color: #374151;
            font-weight: 600;
            font-size: 14px;
        }

        .form-group input {
            padding: 12px 14px;
            border: 1.5px solid #e5e7eb;
            border-radius: 8px;
            font-size: 16px;
            transition: border-color 0.2s, box-shadow 0.2s;
            background: #f9fafb;
            color: #111827;
        }

        .form-group input:focus {
            outline: none;
            border-color: #f59e0b;
            box-shadow: 0 0 0 3px rgba(245,158,11,0.18);
            background: #fff;
        }

        .login-btn {
            padding: 13px;
            background: #f59e0b;
            color: #000;
            border: none;
            border-radius: 9px;
            font-size: 15px;
            font-weight: 700;
            cursor: pointer;
            transition: transform 0.18s, box-shadow 0.18s, background 0.18s;
            letter-spacing: 0.08em;
            text-transform: uppercase;
        }

        .login-btn:hover {
            transform: translateY(-2px);
            background: #d97706;
            color: #fff;
            box-shadow: 0 5px 15px rgba(245, 158, 11, 0.4);
        }

        .login-btn:active {
            transform: translateY(0);
        }

        .error-message {
            padding: 12px;
            background: #fef2f2;
            border: 1px solid #fecaca;
            border-radius: 4px;
            color: #b91c1c;
            font-size: 14px;
            text-align: center;
        }

        /* 深色模式 */
        [data-theme="dark"] .login-container {
            background: #1f2937;
            border-top-color: #d97706;
            box-shadow: 0 10px 40px rgba(0,0,0,0.5);
        }
        [data-theme="dark"] .login-header h1 { color: #f3f4f6; }
        [data-theme="dark"] .login-header p  { color: #9ca3af; }
        [data-theme="dark"] .form-group label { color: #d1d5db; }
        [data-theme="dark"] .form-group input {
            background: #374151;
            border-color: #4b5563;
            color: #f9fafb;
        }
        [data-theme="dark"] .form-group input:focus {
            border-color: #d97706;
            background: #374151;
        }
        [data-theme="dark"] .login-btn {
            background: #d97706;
            color: #fff;
        }
        [data-theme="dark"] .login-btn:hover {
            background: #b45309;
        }

        /* 語言切換按鈕 */
        .lang-toggle {
            background: transparent;
            border: 1px solid rgba(245,158,11,0.5);
            color: #d97706;
            padding: 5px 12px;
            border-radius: 4px;
            font-size: 12px;
            font-weight: 700;
            cursor: pointer;
            letter-spacing: 1px;
            transition: background 0.2s, color 0.2s;
            font-family: inherit;
        }
        .lang-toggle:hover {
            background: #f59e0b;
            color: #000;
        }
        [data-theme="dark"] .lang-toggle {
            border-color: rgba(217,119,6,0.6);
            color: #fbbf24;
        }
        [data-theme="dark"] .lang-toggle:hover {
            background: #d97706;
            color: #fff;
        }