/* Light theme (default) */
        :root {
            --bg-primary: #f8fafc;
            --bg-secondary: #ffffff;
            --bg-card: #e2e8f0;
            --text-primary: #1e293b;
            --text-secondary: #64748b;
            --accent-green: #22c55e;
            --accent-red: #ef4444;
            --accent-blue: #3b82f6;
            --accent-yellow: #eab308;
            --accent-purple: #a855f7;
            --accent-cyan: #06b6d4;
            --chart-grid: #e2e8f0;
            --chart-text: #64748b;
        }

        /* Dark theme */
        [data-theme="dark"] {
            --bg-primary: #0f172a;
            --bg-secondary: #1e293b;
            --bg-card: #334155;
            --text-primary: #f1f5f9;
            --text-secondary: #94a3b8;
            --chart-grid: #334155;
            --chart-text: #94a3b8;
        }

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

        body {
            font-family: 'Segoe UI', -apple-system, BlinkMacSystemFont, sans-serif;
            background: var(--bg-primary);
            color: var(--text-primary);
            min-height: 100vh;
            transition: background 0.3s, color 0.3s;
        }

        .container {
            max-width: 1400px;
            margin: 0 auto;
            padding: 20px;
        }

        header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 20px;
            padding-bottom: 20px;
            border-bottom: 1px solid var(--bg-card);
        }

        h1 {
            font-size: 1.8rem;
            font-weight: 600;
        }

        .subtitle {
            color: var(--text-secondary);
            font-size: 0.9rem;
            margin-top: 5px;
        }

        .header-right {
            display: flex;
            align-items: center;
            gap: 20px;
        }

        .nav-links {
            display: flex;
            gap: 10px;
        }

        .nav-links a {
            color: var(--text-secondary);
            text-decoration: none;
            padding: 8px 16px;
            border-radius: 8px;
            transition: all 0.2s;
        }

        .nav-links a:hover {
            background: var(--bg-card);
            color: var(--text-primary);
        }

        .nav-links a.active {
            background: var(--bg-card);
            color: var(--text-primary);
            font-weight: 500;
        }

        /* Theme Toggle */
        .theme-toggle {
            display: flex;
            align-items: center;
            gap: 8px;
            padding: 6px 12px;
            background: var(--bg-secondary);
            border: 1px solid var(--bg-card);
            border-radius: 8px;
            cursor: pointer;
            color: var(--text-secondary);
            font-size: 0.85rem;
            transition: all 0.2s;
        }

        .theme-toggle:hover {
            background: var(--bg-card);
            color: var(--text-primary);
        }

        .theme-icon {
            font-size: 1.1rem;
        }

        /* Top Bar */
        .top-bar {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 20px;
            flex-wrap: wrap;
            gap: 15px;
        }

        .update-info {
            color: var(--text-secondary);
            font-size: 0.85rem;
        }

        /* Tab Navigation */
        .tab-container {
            display: flex;
            gap: 5px;
            margin-bottom: 25px;
            flex-wrap: wrap;
            background: var(--bg-secondary);
            padding: 10px;
            border-radius: 12px;
        }

        .tab-btn {
            padding: 10px 16px;
            border: none;
            background: transparent;
            color: var(--text-secondary);
            cursor: pointer;
            border-radius: 8px;
            font-size: 0.9rem;
            transition: all 0.2s;
            white-space: nowrap;
        }

        .tab-btn:hover {
            background: var(--bg-card);
            color: var(--text-primary);
        }

        .tab-btn.active {
            background: var(--accent-blue);
            color: white;
        }

        /* Dropdown for "其他" */
        .tab-dropdown {
            position: relative;
            display: inline-block;
        }

        .tab-dropdown-btn {
            padding: 10px 16px;
            border: none;
            background: transparent;
            color: var(--text-secondary);
            cursor: pointer;
            border-radius: 8px;
            font-size: 0.9rem;
            transition: all 0.2s;
            white-space: nowrap;
            display: flex;
            align-items: center;
            gap: 4px;
        }

        .tab-dropdown-btn:hover {
            background: var(--bg-card);
            color: var(--text-primary);
        }

        .tab-dropdown-btn.has-active {
            background: var(--accent-blue);
            color: white;
        }

        .tab-dropdown-content {
            display: none;
            position: absolute;
            top: 100%;
            right: 0;
            background: var(--bg-secondary);
            border: 1px solid var(--bg-card);
            border-radius: 8px;
            min-width: 180px;
            box-shadow: 0 4px 12px rgba(0,0,0,0.15);
            z-index: 100;
            margin-top: 4px;
        }

        .tab-dropdown:hover .tab-dropdown-content,
        .tab-dropdown.open .tab-dropdown-content {
            display: block;
        }

        .tab-dropdown-content .tab-btn {
            display: block;
            width: 100%;
            text-align: left;
            border-radius: 0;
            padding: 10px 14px;
        }

        .tab-dropdown-content .tab-btn:first-child {
            border-radius: 8px 8px 0 0;
        }

        .tab-dropdown-content .tab-btn:last-child {
            border-radius: 0 0 8px 8px;
        }

        .tab-dropdown-content .tab-btn.deprecated {
            color: var(--text-secondary);
            font-size: 0.85rem;
        }

        .tab-dropdown-content .tab-btn.deprecated::after {
            content: " ⚠️ 已停更";
            font-size: 0.7rem;
            opacity: 0.7;
        }

        /* Cards Grid */
        .grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
            gap: 12px;
            margin-bottom: 20px;
        }

        .card {
            background: var(--bg-secondary);
            border-radius: 10px;
            padding: 15px;
            border: 1px solid var(--bg-card);
            transition: background 0.3s, border 0.3s;
        }

        .card-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 10px;
        }

        .card-title {
            font-size: 0.9rem;
            color: var(--text-secondary);
            font-weight: 500;
        }

        .card-value {
            font-size: 1.6rem;
            font-weight: 700;
        }

        .card-change {
            font-size: 0.9rem;
            padding: 4px 8px;
            border-radius: 4px;
        }

        .positive {
            color: var(--accent-green);
            background: rgba(34, 197, 94, 0.1);
        }

        .negative {
            color: var(--accent-red);
            background: rgba(239, 68, 68, 0.1);
        }

        .neutral {
            color: var(--text-secondary);
            background: rgba(148, 163, 184, 0.1);
        }

        .section-title {
            font-size: 1.2rem;
            margin-bottom: 20px;
            padding-bottom: 10px;
            border-bottom: 1px solid var(--bg-card);
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 10px;
            flex-wrap: wrap;
        }

        /* Zoom Controls */
        .zoom-controls {
            display: flex;
            gap: 5px;
            flex-wrap: wrap;
        }

        .zoom-btn {
            padding: 5px 12px;
            border: 1px solid var(--bg-card);
            background: transparent;
            color: var(--text-secondary);
            cursor: pointer;
            border-radius: 4px;
            font-size: 0.8rem;
            transition: all 0.2s;
        }

        .zoom-btn:hover {
            background: var(--bg-card);
            color: var(--text-primary);
        }

        .zoom-btn.active {
            background: var(--accent-blue);
            color: white;
            border-color: var(--accent-blue);
        }

        /* Table */
        .data-table {
            width: 100%;
            border-collapse: collapse;
            font-size: 0.9rem;
        }

        .data-table th,
        .data-table td {
            padding: 10px 12px;
            text-align: right;
            border-bottom: 1px solid var(--bg-card);
        }

        .data-table th:first-child,
        .data-table td:first-child {
            text-align: left;
            position: sticky;
            left: 0;
            background: var(--bg-secondary);
            z-index: 1;
        }

        .data-table th {
            color: var(--text-secondary);
            font-weight: 500;
            font-size: 0.85rem;
            position: sticky;
            top: 0;
            background: var(--bg-secondary);
        }

        .data-table th:first-child {
            z-index: 2;
        }

        .data-table tr:hover td:first-child {
            background: var(--bg-card);
        }

        .data-table tr:hover {
            background: var(--bg-card);
        }

        .table-container {
            max-height: 600px;
            overflow: auto;
        }

        /* Chart Container */
        .chart-container {
            height: 400px;
            margin-top: 20px;
        }

        /* Info Box */
        .info-box {
            background: linear-gradient(135deg, var(--bg-card), var(--bg-secondary));
            border-radius: 12px;
            padding: 20px;
            border-left: 4px solid var(--accent-blue);
            margin-bottom: 30px;
        }

        .info-box h3 {
            margin-bottom: 10px;
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .info-box p {
            color: var(--text-secondary);
            line-height: 1.6;
        }

        /* Responsive */
        @media (max-width: 768px) {
            header {
                flex-direction: column;
                align-items: flex-start;
                gap: 15px;
            }

            h1 {
                font-size: 1.3rem;
                display: flex;
                align-items: center;
                flex-wrap: wrap;
                gap: 8px;
            }

            h1 .footer-internal {
                font-size: 0.65rem;
            }

            .subtitle {
                font-size: 0.8rem;
            }

            .header-right {
                width: 100%;
                flex-direction: row;
                justify-content: space-between;
                align-items: center;
            }

            .nav-links {
                gap: 6px;
            }

            .nav-links a {
                padding: 6px 12px;
                font-size: 0.85rem;
                white-space: nowrap;
            }

            .theme-toggle {
                padding: 4px 8px;
                font-size: 0.8rem;
            }

            .tab-container {
                overflow-x: auto;
                overflow-y: visible;
                flex-wrap: nowrap;
                padding-bottom: 15px;
            }

            /* 手機版 dropdown 使用 fixed 定位避免被 overflow 裁切 */
            .tab-dropdown-content {
                position: fixed;
                top: auto;
                right: 10px;
                left: auto;
                max-height: 60vh;
                overflow-y: auto;
            }

            .grid {
                grid-template-columns: repeat(2, 1fr);
                gap: 8px;
            }

            .card {
                padding: 12px;
            }

            .card-value {
                font-size: 1.3rem;
            }

            .card-title {
                font-size: 0.8rem;
            }
        }

        /* Footer */
        .footer {
            margin-top: 40px;
            padding: 20px;
            text-align: center;
            border-top: 1px solid var(--bg-card);
            color: var(--text-secondary);
            font-size: 0.85rem;
        }

        .footer-links {
            margin-bottom: 12px;
        }

        .footer-links a {
            color: var(--text-secondary);
            text-decoration: none;
            transition: color 0.2s;
        }

        .footer-links a:hover {
            color: var(--text-primary);
        }

        .footer-divider {
            margin: 0 8px;
            color: var(--bg-card);
        }

        .footer-brand {
            font-weight: 600;
            color: var(--text-primary);
        }

        .footer-internal {
            display: inline-block;
            margin-left: 8px;
            padding: 2px 8px;
            background: var(--accent-yellow);
            color: #000;
            border-radius: 4px;
            font-size: 0.75rem;
            font-weight: 500;
        }

        .version {
            margin-top: 8px;
            font-size: 0.75rem;
            color: var(--text-secondary);
            opacity: 0.6;
        }

        /* Indicator Info Toggle */
        .indicator-info {
            margin-bottom: 20px;
        }

        .info-toggle {
            display: inline-flex;
            align-items: center;
            gap: 6px;
            padding: 8px 12px;
            background: var(--bg-card);
            border: none;
            border-radius: 6px;
            color: var(--text-secondary);
            font-size: 0.85rem;
            cursor: pointer;
            transition: all 0.2s;
        }

        .info-toggle:hover {
            background: var(--bg-secondary);
            color: var(--text-primary);
        }

        .info-toggle .arrow {
            transition: transform 0.2s;
        }

        .info-toggle.open .arrow {
            transform: rotate(180deg);
        }

        .info-content {
            display: none;
            margin-top: 12px;
            padding: 16px;
            background: var(--bg-secondary);
            border: 1px solid var(--bg-card);
            border-radius: 8px;
            color: var(--text-secondary);
            font-size: 0.9rem;
            line-height: 1.7;
        }

        .info-content.open {
            display: block;
        }

        /* Pivot Matrix Styles */
        .pivot-section {
            margin-top: 30px;
        }

        .pivot-section-title {
            font-size: 1.1rem;
            font-weight: 600;
            margin-bottom: 15px;
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .pivot-variant-label {
            font-size: 0.75rem;
            padding: 3px 8px;
            background: var(--accent-purple);
            color: white;
            border-radius: 4px;
            font-weight: 500;
        }

        /* Pivot Region Tabs (方案 C) */
        .pivot-tabs {
            display: flex;
            gap: 4px;
            margin-bottom: 15px;
            flex-wrap: wrap;
            background: var(--bg-card);
            padding: 6px;
            border-radius: 10px;
        }

        .pivot-tab {
            padding: 8px 14px;
            border: none;
            background: transparent;
            color: var(--text-secondary);
            cursor: pointer;
            border-radius: 6px;
            font-size: 0.85rem;
            transition: all 0.2s;
            white-space: nowrap;
        }

        .pivot-tab:hover {
            background: var(--bg-secondary);
            color: var(--text-primary);
        }

        .pivot-tab.active {
            background: var(--accent-blue);
            color: white;
        }

        /* Pivot Region Dropdown (方案 A) */
        .pivot-dropdown-container {
            margin-bottom: 15px;
        }

        .pivot-dropdown {
            padding: 10px 14px;
            border: 1px solid var(--bg-card);
            background: var(--bg-secondary);
            color: var(--text-primary);
            border-radius: 8px;
            font-size: 0.9rem;
            cursor: pointer;
            min-width: 150px;
        }

        .pivot-dropdown:focus {
            outline: none;
            border-color: var(--accent-blue);
        }

        .pivot-nav-btn {
            padding: 8px 12px;
            border: 1px solid var(--bg-card);
            background: var(--bg-secondary);
            color: var(--text-primary);
            border-radius: 6px;
            font-size: 0.9rem;
            cursor: pointer;
            transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
        }

        .pivot-nav-btn:hover:not(:disabled) {
            background: var(--accent-blue);
            color: white;
            border-color: var(--accent-blue);
        }

        .pivot-nav-btn:focus-visible {
            outline: 2px solid var(--accent-blue);
            outline-offset: 2px;
        }

        .pivot-nav-btn:disabled {
            opacity: 0.5;
            cursor: not-allowed;
        }

        /* Pivot Table */
        .pivot-table {
            width: 100%;
            border-collapse: collapse;
            font-size: 0.9rem;
        }

        .pivot-table th,
        .pivot-table td {
            padding: 10px 12px;
            text-align: center;
            border: 1px solid var(--bg-card);
        }

        .pivot-table th {
            background: var(--bg-card);
            color: var(--text-secondary);
            font-weight: 600;
            font-size: 0.85rem;
        }

        .pivot-table th:first-child {
            text-align: left;
            width: 80px;
        }

        .pivot-table td:first-child {
            text-align: left;
            font-weight: 600;
            background: var(--bg-card);
        }

        .pivot-table .year-total {
            background: rgba(59, 130, 246, 0.1);
            font-weight: 600;
            color: var(--accent-blue);
        }

        .pivot-table tr:hover td:not(:first-child) {
            background: rgba(59, 130, 246, 0.05);
        }

        /* Table + Chart Layout (左表右圖) */
        .table-chart-layout {
            display: grid;
            grid-template-columns: 2fr 1fr;
            gap: 15px;
            align-items: start;
        }

        .table-chart-layout .pivot-table-side {
            min-width: 0;
            overflow-x: auto;
        }

        .table-chart-layout .chart-side {
            min-width: 0;
            height: 180px;
        }

        .table-chart-layout .pivot-table {
            font-size: 0.8rem;
        }

        .table-chart-layout .pivot-table th,
        .table-chart-layout .pivot-table td {
            padding: 6px 8px;
            white-space: nowrap;
        }

        @media (max-width: 900px) {
            .table-chart-layout {
                grid-template-columns: 1fr;
            }

            .table-chart-layout .chart-side {
                height: 160px;
            }
        }

        /* Stacked Matrices (方案 D) */
        .stacked-matrices {
            display: flex;
            flex-direction: column;
            gap: 25px;
        }

        .stacked-matrix-item {
            border: 1px solid var(--bg-card);
            border-radius: 10px;
            padding: 15px;
            background: var(--bg-primary);
        }

        .stacked-matrix-title {
            font-size: 1rem;
            font-weight: 600;
            margin-bottom: 12px;
            padding-bottom: 8px;
            border-bottom: 2px solid var(--accent-blue);
            color: var(--accent-blue);
        }

        /* Comparison Matrix (方案 E) */
        .comparison-table {
            width: 100%;
            border-collapse: collapse;
            font-size: 0.85rem;
        }

        .comparison-table th,
        .comparison-table td {
            padding: 10px 8px;
            text-align: right;
            border: 1px solid var(--bg-card);
        }

        .comparison-table th {
            background: var(--bg-card);
            color: var(--text-secondary);
            font-weight: 600;
            font-size: 0.8rem;
        }

        .comparison-table th:first-child {
            text-align: left;
        }

        .comparison-table td:first-child {
            text-align: left;
            font-weight: 500;
            background: var(--bg-card);
        }

        .comparison-table .change-positive {
            color: var(--accent-green);
        }

        .comparison-table .change-negative {
            color: var(--accent-red);
        }

        .comparison-table tr:hover td {
            background: rgba(59, 130, 246, 0.05);
        }

        .comparison-table tr:hover td:first-child {
            background: var(--bg-card);
        }

        /* Responsive for pivot */
        @media (max-width: 768px) {
            .pivot-tabs {
                overflow-x: auto;
                flex-wrap: nowrap;
                -webkit-overflow-scrolling: touch;
            }

            .pivot-table-side {
                overflow-x: auto;
                -webkit-overflow-scrolling: touch;
            }

            .pivot-table {
                font-size: 0.8rem;
                min-width: 320px;
            }

            .pivot-table th,
            .pivot-table td {
                padding: 6px 4px;
                white-space: nowrap;
            }
        }

        /* Data Source */
        .data-source {
            margin-top: 16px;
            padding: 10px 14px;
            background: var(--bg-card);
            border-radius: 6px;
            font-size: 0.8rem;
            color: var(--text-secondary);
        }

        .data-source strong {
            color: var(--text-primary);
        }

        .data-footnote {
            margin-top: 12px;
            padding: 8px 14px;
            font-size: 0.75rem;
            color: var(--text-secondary);
            border-left: 3px solid var(--accent-blue);
            background: rgba(59, 130, 246, 0.05);
            border-radius: 0 4px 4px 0;
        }

        .data-footnote sup {
            color: var(--accent-blue);
            font-weight: 600;
        }

        /* Export Buttons (AI-friendly) */
        .export-toolbar {
            display: flex;
            gap: 8px;
            margin-top: 12px;
            flex-wrap: wrap;
        }

        .export-btn {
            display: inline-flex;
            align-items: center;
            gap: 6px;
            padding: 8px 14px;
            border: 1px solid var(--bg-card);
            background: var(--bg-secondary);
            color: var(--text-secondary);
            border-radius: 6px;
            font-size: 0.8rem;
            cursor: pointer;
            transition: all 0.2s;
        }

        .export-btn:hover {
            background: var(--bg-card);
            color: var(--text-primary);
            border-color: var(--accent-blue);
        }

        .export-btn.success {
            background: var(--accent-green);
            color: white;
            border-color: var(--accent-green);
        }

        .export-btn .icon {
            font-size: 1rem;
        }

        /* Table export wrapper (for screenshot) */
        .table-export-wrapper {
            background: #ffffff;
            padding: 16px;
            border-radius: 8px;
        }

        .table-export-title {
            font-size: 1.1rem;
            font-weight: 600;
            color: var(--text-primary);
            margin-bottom: 12px;
            padding-bottom: 8px;
            border-bottom: 2px solid var(--accent-blue);
        }

        .table-export-source {
            margin-top: 12px;
            font-size: 0.8rem;
            color: var(--text-secondary);
        }

        /* Watermark overlay */
        .watermark-container {
            position: relative;
        }

        .watermark-container::after {
            content: '';
            position: absolute;
            top: 12%;
            left: 4%;
            width: 140px;
            height: 50px;
            background-image: url('/data/HRE_logo.png');
            background-size: contain;
            background-repeat: no-repeat;
            background-position: center;
            opacity: 0.35;
            pointer-events: none;
            z-index: 10;
        }

        /* Mobile watermark adjustment */
        @media (max-width: 768px) {
            .watermark-container::after {
                top: 15%;
                left: 12%;
                width: 115px;
                height: 42px;
            }
        }

        /* Building transfer specific watermark adjustment */
        .watermark-container.building-transfer::after {
            top: 14%;
            left: 8%;
        }

        @media (max-width: 768px) {
            .watermark-container.building-transfer::after {
                top: 17%;
                left: 16%;
            }
        }

        /* Collapsible Sections */
        .collapsible-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            cursor: pointer;
            user-select: none;
            padding: 12px 0;
            margin: 0;
        }

        .collapsible-header:hover {
            color: var(--accent-blue);
        }

        .collapse-arrow {
            transition: transform 0.2s;
            font-size: 0.8rem;
            color: var(--text-secondary);
        }

        .collapsible-header.collapsed .collapse-arrow {
            transform: rotate(-90deg);
        }

        .collapsible-content {
            transition: max-height 0.3s ease-out;
            overflow: hidden;
        }

        .collapsible-content.collapsed {
            display: none;
        }