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

        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            align-items: center;
            padding: 14px;
        }

        .container {
            background: white;
            border-radius: 20px;
            box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
            padding: 26px 24px 28px;
            max-width: 900px;
            width: 100%;
            margin-top: 12px;
        }

        h1 {
            color: #333;
            font-size: 24px;
            margin-bottom: 0;
            line-height: 1.05;
            text-align: center;
        }

        .subtitle {
            color: #666;
            text-align: center;
            margin-bottom: 16px;
            font-size: 13px;
        }

        .hero-note {
            margin-top: -2px;
            margin-bottom: 0;
            font-size: 13px;
            color: #555;
            text-align: center;
        }

        .hero-note summary {
            cursor: pointer;
            list-style: none;
            display: inline-flex;
            align-items: center;
            gap: 6px;
            justify-content: center;
            padding: 0;
            margin: 0;
        }

        .hero-note summary::-webkit-details-marker {
            display: none;
        }

        .hero-note summary::after {
            content: '+';
            font-weight: 600;
            font-size: 14px;
        }

        .hero-note[open] summary::after {
            content: '-';
        }

        .hero-note p {
            margin-top: 6px;
            line-height: 1.4;
        }

        .hero-inline {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            justify-content: center;
            flex-wrap: wrap;
            width: 100%;
        }

        .hero-inline .hero-note {
            margin: 0;
        }

        /* Collapsible wrappers to keep SEO text present but tucked away */
        .seo-accordions {
            width: 100%;
            max-width: 900px;
            margin: 32px auto;
            display: flex;
            flex-direction: column;
            gap: 0;
        }

        .seo-accordion {
            width: 100%;
            border: 1px solid #e5e7eb;
            border-radius: 12px;
            background: #fff;
            overflow: hidden;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
        }

        .seo-accordion + .seo-accordion {
            border-top: 0;
        }

        .seo-accordion summary {
            padding: 14px 16px;
            font-weight: 600;
            cursor: pointer;
            list-style: none;
            display: flex;
            align-items: center;
            gap: 10px;
            background: #f7f7fb;
            min-height: 48px;
        }

        .seo-accordion summary::-webkit-details-marker {
            display: none;
        }

        .seo-accordion summary::after {
            content: '+';
            margin-left: auto;
            font-size: 18px;
            line-height: 1;
        }

        .seo-accordion[open] summary::after {
            content: '-';
        }

        .seo-accordion-body {
            padding: 16px;
            background: #fff;
        }

        /* ===== SIMPLE MODE ===== */
        .mode-simple {
            display: flex;
            flex-direction: column;
            gap: 20px;
        }

        .mode-simple.hidden {
            display: none;
        }

        .two-column {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 30px;
        }

        @media (max-width: 768px) {
            .two-column {
                grid-template-columns: 1fr;
            }
        }

        .file-input-wrapper {
            display: flex;
            flex-direction: column;
        }

        .file-input-label {
            font-weight: 600;
            color: #333;
            margin-bottom: 10px;
            font-size: 16px;
        }

        .file-input-group {
            position: relative;
            cursor: pointer;
        }

        .file-input-group input[type="file"] {
            display: none;
        }

        .file-input-display {
            padding: 20px;
            border: 2px dashed #667eea;
            border-radius: 12px;
            text-align: center;
            transition: all 0.3s ease;
            background: #f8f9fa;
            cursor: pointer;
            min-height: 200px;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
        }

        .file-input-display:hover {
            border-color: #764ba2;
            background: #f0f0ff;
        }

        .file-input-display.has-file {
            border-color: #667eea;
            background: #f0f4ff;
        }

        .file-input-display.upload-error-glow,
        .drop-zone.upload-error-glow {
            border-color: #e24b4b;
            animation: uploadErrorGlow 0.9s ease;
        }

        @keyframes uploadErrorGlow {
            0% {
                box-shadow: 0 0 0 0 rgba(226, 75, 75, 0);
            }
            35% {
                box-shadow: 0 0 0 4px rgba(226, 75, 75, 0.35), 0 0 18px rgba(226, 75, 75, 0.5);
            }
            100% {
                box-shadow: 0 0 0 0 rgba(226, 75, 75, 0);
            }
        }

        .file-input-icon {
            font-size: 32px;
            margin-bottom: 10px;
        }

        .file-input-text {
            color: #667eea;
            font-weight: 600;
            font-size: 14px;
        }

        .file-input-subtext {
            color: #999;
            font-size: 12px;
            margin-top: 5px;
        }

        .file-name {
            color: #333;
            font-weight: 600;
            margin-top: 10px;
            word-break: break-word;
            font-size: 15px;
        }

        .file-size {
            color: #999;
            font-size: 14px;
            margin-top: 5px;
        }

        .file-clear-btn {
            background: none;
            border: none;
            color: #999;
            cursor: pointer;
            font-size: 13px;
            margin-top: 8px;
            text-decoration: underline;
            transition: color 0.2s;
            padding: 0;
        }

        .file-clear-btn:hover {
            color: #667eea;
        }

        .expand-section {
            text-align: center;
            padding: 20px 0;
            margin-top: 20px;
        }

        /* ===== SIMPLE MODE REORGANIZED ===== */
        
        .simple-merge-section {
            padding: 0;
            text-align: center;
            margin: 20px 0 0 0;
        }

        .merge-btn-large {
            width: 100%;
            padding: 20px 40px !important;
            font-size: 18px !important;
            letter-spacing: 0.5px;
            box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4) !important;
            margin-bottom: 2px !important;
        }

        .merge-btn-large:hover:not(:disabled) {
            transform: translateY(-3px) !important;
            box-shadow: 0 8px 25px rgba(102, 126, 234, 0.5) !important;
        }

        .merge-btn-large:disabled {
            opacity: 0.5;
            cursor: not-allowed;
        }

        .simple-merge-hint {
            color: #999;
            font-size: 13px;
            margin-top: 2px;
            margin-bottom: 0;
            font-style: italic;
        }

        .compression-partner-link {
            margin-top: 10px;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            flex-wrap: wrap;
            font-size: 13px;
            color: #6b7280;
        }

        .compression-partner-text {
            white-space: nowrap;
        }

        .compression-partner-link a {
            display: inline-flex;
            align-items: center;
            gap: 6px;
            color: #0f766e;
            font-weight: 700;
            text-decoration: none;
            padding: 4px 8px;
            border-radius: 999px;
            border: 1px solid #99f6e4;
            background: #f0fdfa;
            transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
        }

        .compression-partner-link a:hover {
            background: #ccfbf1;
            border-color: #5eead4;
            color: #115e59;
        }

        .compression-partner-link img {
            display: block;
            border-radius: 4px;
        }

        .simple-options-section {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 2px;
            margin-top: 2px;
        }

        .simple-options-btn {
            background: linear-gradient(135deg, #10b981 0%, #059669 100%);
            color: white;
            border: none;
            padding: 14px 15px;
            border-radius: 10px;
            font-weight: 600;
            font-size: 14px;
            cursor: pointer;
            transition: all 0.2s;
            box-shadow: 0 4px 12px rgba(16, 185, 129, 0.3);
        }

        .simple-options-btn:hover:not(:disabled) {
            transform: translateY(-2px);
            box-shadow: 0 6px 16px rgba(16, 185, 129, 0.4);
        }

        .simple-options-btn:disabled {
            opacity: 0.5;
            cursor: not-allowed;
        }

        .expand-btn {
            background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%) !important;
            color: white !important;
            border: none !important;
        }

        .expand-btn:hover:not(:disabled) {
            transform: translateY(-2px) !important;
            box-shadow: 0 6px 16px rgba(245, 158, 11, 0.4) !important;
        }

        @media (max-width: 768px) {
            .simple-options-section {
                grid-template-columns: 1fr;
            }

            .compression-partner-link {
                flex-direction: column;
                gap: 6px;
            }

            .compression-partner-text {
                white-space: normal;
            }
        }

        /* ===== FILENAME INPUT (NEW) ===== */
        .filename-input-row {
            margin-top: 8px;
            display: flex;
            justify-content: center;
            align-items: center;
            gap: 8px;
            font-size: 13px;
            color: #555;
            grid-column: 1 / -1;
        }

        .filename-input-row input {
            padding: 6px 10px;
            border-radius: 8px;
            border: 1px solid #ddd;
            font-size: 13px;
            width: 230px;
        }

        /* ===== EXPANDED MODE ===== */
        .mode-expanded {
            display: none;
        }

        .mode-expanded.active {
            display: flex;
            flex-direction: column;
            gap: 20px;
        }

        .mode-toggle-header {
            display: flex;
            align-items: center;
            gap: 15px;
            margin-bottom: 20px;
            padding-bottom: 20px;
            border-bottom: 1px solid #eee;
        }

        .back-to-simple {
            background: none;
            border: none;
            color: #667eea;
            cursor: pointer;
            font-weight: 600;
            text-decoration: underline;
            font-size: 14px;
            transition: color 0.2s;
        }

        .back-to-simple:hover {
            color: #764ba2;
        }

        .mode-title {
            font-size: 20px;
            font-weight: 600;
            color: #333;
            flex: 1;
        }

        .document-count {
            background: #667eea;
            color: white;
            padding: 4px 12px;
            border-radius: 20px;
            font-size: 13px;
            font-weight: 600;
        }

        .drop-zone {
            border: 2px dashed #667eea;
            border-radius: 12px;
            padding: 40px 20px;
            text-align: center;
            cursor: pointer;
            transition: all 0.3s ease;
            background: #f8f9fa;
        }

        .drop-zone:hover {
            border-color: #764ba2;
            background: #f0f0ff;
        }

        .drop-zone.dragover {
            border-color: #764ba2;
            background: #e0e7ff;
            transform: scale(1.02);
        }

        .drop-zone-text {
            color: #667eea;
            font-weight: 600;
            font-size: 16px;
        }

        .drop-zone-subtext {
            color: #999;
            font-size: 14px;
            margin-top: 8px;
        }

        .drop-zone input[type="file"] {
            display: none;
        }

        .pdf-list {
            display: flex;
            flex-direction: column;
            gap: 12px;
        }

        .pdf-card {
            background: #f8f9fa;
            border: 1px solid #e0e0e0;
            border-radius: 10px;
            padding: 15px;
            display: flex;
            align-items: center;
            gap: 12px;
            cursor: grab;
            transition: all 0.2s ease;
        }

        .pdf-card.pdf-card-invalid {
            border-color: #f5c6cb;
            background: #fdf2f3;
        }

        .pdf-card.pdf-card-invalid .pdf-name,
        .pdf-card.pdf-card-invalid .pdf-size {
            color: #8b2b2f;
        }

        .pdf-issue {
            margin-top: 6px;
            font-size: 12px;
            font-weight: 600;
            color: #b2343b;
        }

        .pdf-card:hover {
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
            border-color: #667eea;
        }

        .pdf-card.dragging {
            opacity: 0.5;
            cursor: grabbing;
        }

        .drag-handle {
            color: #999;
            cursor: grab;
            font-size: 20px;
            display: flex;
            align-items: center;
            justify-content: center;
            width: 24px;
            flex-shrink: 0;
        }

        .pdf-card.dragging .drag-handle {
            cursor: grabbing;
        }

        .pdf-order {
            background: #667eea;
            color: white;
            width: 32px;
            height: 32px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 600;
            font-size: 14px;
            flex-shrink: 0;
        }

        .pdf-info {
            flex: 1;
            min-width: 0;
        }

        .pdf-name {
            font-weight: 600;
            color: #333;
            word-break: break-word;
            font-size: 15px;
        }

        .pdf-size {
            color: #999;
            font-size: 13px;
            margin-top: 4px;
        }

        .pdf-delete {
            background: none;
            border: none;
            color: #999;
            cursor: pointer;
            font-size: 20px;
            padding: 5px;
            flex-shrink: 0;
            transition: color 0.2s;
        }

        .pdf-delete:hover {
            color: #ff4757;
        }

        .add-more-section {
            text-align: center;
            padding: 20px;
            background: #f8f9fa;
            border-radius: 10px;
            border: 1px dashed #ddd;
        }

        .add-more-btn {
            background: none;
            border: none;
            color: #667eea;
            cursor: pointer;
            font-weight: 600;
            font-size: 15px;
            text-decoration: underline;
            transition: color 0.2s;
        }

        .add-more-btn:hover {
            color: #764ba2;
        }

        /* ===== BUTTONS ===== */
        .button-group {
            display: flex;
            gap: 15px;
            justify-content: center;
            margin-top: 20px;
            flex-wrap: wrap;
        }

        .merge-btn {
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            border: none;
            padding: 16px 40px;
            border-radius: 10px;
            font-weight: 600;
            font-size: 16px;
            cursor: pointer;
            transition: all 0.3s ease;
            box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
        }

        .merge-btn:hover:not(:disabled) {
            transform: translateY(-2px);
            box-shadow: 0 6px 20px rgba(102, 126, 234, 0.6);
        }

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

        .merge-btn.loading {
            position: relative;
            color: transparent;
        }

        .merge-btn.loading::after {
            content: '';
            position: absolute;
            width: 20px;
            height: 20px;
            top: 50%;
            left: 50%;
            margin-left: -10px;
            margin-top: -10px;
            border: 3px solid rgba(255, 255, 255, 0.3);
            border-radius: 50%;
            border-top-color: white;
            animation: spin 0.8s linear infinite;
        }

        @keyframes spin {
            to { transform: rotate(360deg); }
        }

        .memory-warning {
            background: #fff3cd;
            border: 1px solid #ffc107;
            border-radius: 8px;
            padding: 12px 15px;
            color: #856404;
            font-size: 13px;
            margin-top: 15px;
            display: none;
        }

        .memory-warning.show {
            display: block;
        }

        .error-message {
            background: #f8d7da;
            border: 1px solid #f5c6cb;
            border-radius: 8px;
            padding: 12px 15px;
            color: #721c24;
            font-size: 14px;
            margin-top: 15px;
            display: none;
        }

        .error-message.show {
            display: block;
        }

        .error-action {
            display: none;
            margin-top: 8px;
        }

        .error-action.show {
            display: block;
        }

        .error-action-btn {
            background: #f8d7da;
            border: 1px solid #f5c6cb;
            color: #721c24;
            padding: 8px 12px;
            border-radius: 6px;
            font-size: 12px;
            cursor: pointer;
            font-weight: 600;
        }

        .error-action-btn:hover {
            background: #f3c8cd;
        }

        .status-area {
            margin-top: 20px;
            padding: 15px;
            border-radius: 10px;
            text-align: center;
            font-size: 14px;
            font-weight: 500;
            min-height: 50px;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .status-ready {
            background: #e0e7ff;
            color: #4c51bf;
        }

        .status-processing {
            background: #fef3c7;
            color: #d97706;
        }

        .status-success {
            background: #d1fae5;
            color: #059669;
        }

        .status-error {
            background: #fee2e2;
            color: #dc2626;
        }

        .affiliate-inline {
            font-size: 12px;
            color: #6b7280;
        }

        .affiliate-inline a {
            color: #4f46e5;
            font-weight: 600;
            text-decoration: none;
        }

        .affiliate-inline a:hover {
            color: #4338ca;
            text-decoration: underline;
        }

        /* ===== FEATURES & FAQ ===== */
        .features {
            background: white;
            border-radius: 20px;
            box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
            padding: 40px;
            max-width: 900px;
            width: 100%;
            margin-top: 20px;
        }

        .features h2 {
            color: #333;
            font-size: 24px;
            margin-bottom: 20px;
            text-align: center;
        }

        .feature-list {
            list-style: none;
        }

        .feature-list li {
            color: #555;
            margin-bottom: 15px;
            padding-left: 30px;
            position: relative;
            line-height: 1.6;
        }

        .feature-list li:before {
            content: "✓";
            position: absolute;
            left: 0;
            color: #667eea;
            font-weight: bold;
            font-size: 18px;
        }

        .seo-content {
            background: white;
            border-radius: 20px;
            box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
            padding: 40px;
            max-width: 900px;
            width: 100%;
            margin-top: 20px;
            margin-bottom: 20px;
        }

        .seo-content h2 {
            color: #333;
            font-size: 22px;
            margin-bottom: 15px;
        }

        .seo-content p {
            color: #555;
            line-height: 1.8;
            margin-bottom: 15px;
        }

        .seo-content h3 {
            color: #333;
            font-size: 18px;
            margin-top: 25px;
            margin-bottom: 10px;
        }

        .footer-links {
            text-align: center;
            padding: 20px;
            color: white;
        }

        .footer-links a {
            color: white;
            text-decoration: none;
            margin: 0 15px;
        }

        .footer-links a:hover {
            text-decoration: underline;
        }

        .footer-separator {
            color: white;
        }