/* CSS reset & variables */
        :root {
            --primary-gradient: linear-gradient(135deg, #4f46e5, #7c3aed, #ec4899);
            --secondary-gradient: linear-gradient(135deg, #06b6d4, #3b82f6, #6366f1);
            --warm-gradient: linear-gradient(135deg, #f43f5e, #fb7185, #fda4af);
            --text-main: #1e293b;
            --text-muted: #64748b;
            --bg-light: #f8fafc;
            --bg-card: #ffffff;
            --border-color: #e2e8f0;
            --accent-color: #7c3aed;
        }

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

        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans CJK SC", sans-serif;
            color: var(--text-main);
            background-color: var(--bg-light);
            line-height: 1.6;
            overflow-x: hidden;
            position: relative;
        }

        /* Variegated Background Blobs */
        .ambient-blob {
            position: absolute;
            border-radius: 50%;
            filter: blur(120px);
            opacity: 0.12;
            z-index: -1;
            pointer-events: none;
        }
        .blob-1 { top: 10%; left: 5%; width: 400px; height: 400px; background: #4f46e5; }
        .blob-2 { top: 30%; right: 5%; width: 500px; height: 500px; background: #ec4899; }
        .blob-3 { top: 60%; left: 10%; width: 450px; height: 450px; background: #06b6d4; }
        .blob-4 { top: 85%; right: 10%; width: 400px; height: 400px; background: #7c3aed; }

        /* Container */
        .container {
            width: 100%;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }

        /* Typography & Headings */
        h1, h2, h3, h4 {
            font-weight: 700;
            color: #0f172a;
            line-height: 1.25;
        }
        .section-title-wrapper {
            text-align: center;
            margin-bottom: 50px;
        }
        .section-title {
            font-size: 2rem;
            display: inline-block;
            background: var(--primary-gradient);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            margin-bottom: 10px;
            position: relative;
        }
        .section-subtitle {
            font-size: 1rem;
            color: var(--text-muted);
            max-width: 600px;
            margin: 0 auto;
        }

        /* Header & Navigation */
        header {
            position: sticky;
            top: 0;
            background: rgba(255, 255, 255, 0.85);
            backdrop-filter: blur(10px);
            border-bottom: 1px solid var(--border-color);
            z-index: 1000;
            transition: all 0.3s ease;
        }
        .nav-wrapper {
            display: flex;
            justify-content: space-between;
            align-items: center;
            height: 70px;
        }
        .logo-area {
            display: flex;
            align-items: center;
            gap: 10px;
        }
        .ai-page-logo {
            height: 40px;
            width: auto;
        }
        .brand-name {
            font-size: 1.3rem;
            font-weight: 800;
            background: var(--primary-gradient);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }
        .nav-links {
            display: flex;
            gap: 20px;
            align-items: center;
        }
        .nav-item {
            text-decoration: none;
            color: var(--text-main);
            font-size: 0.95rem;
            font-weight: 500;
            transition: color 0.3s ease;
            position: relative;
        }
        .nav-item:hover {
            color: var(--accent-color);
        }
        .nav-dropdown {
            position: relative;
        }
        .dropdown-menu {
            position: absolute;
            top: 100%;
            left: 50%;
            transform: translateX(-50%) translateY(10px);
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            border-radius: 8px;
            box-shadow: 0 10px 25px rgba(0,0,0,0.08);
            padding: 10px 0;
            min-width: 160px;
            opacity: 0;
            pointer-events: none;
            transition: all 0.3s ease;
            z-index: 1010;
        }
        .nav-dropdown:hover .dropdown-menu {
            opacity: 1;
            pointer-events: auto;
            transform: translateX(-50%) translateY(0);
        }
        .dropdown-item {
            display: block;
            padding: 8px 20px;
            font-size: 0.85rem;
            color: var(--text-main);
            text-decoration: none;
            transition: background 0.3s ease, color 0.3s ease;
        }
        .dropdown-item:hover {
            background-color: var(--bg-light);
            color: var(--accent-color);
        }
        .nav-btn {
            background: var(--primary-gradient);
            color: #fff;
            padding: 8px 20px;
            border-radius: 30px;
            text-decoration: none;
            font-weight: 600;
            font-size: 0.9rem;
            box-shadow: 0 4px 15px rgba(124, 58, 237, 0.3);
            transition: transform 0.3s ease, box-shadow 0.3s ease;
        }
        .nav-btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 6px 20px rgba(124, 58, 237, 0.4);
        }
        .mobile-toggle {
            display: none;
            background: none;
            border: none;
            cursor: pointer;
            padding: 5px;
        }
        .mobile-toggle span {
            display: block;
            width: 25px;
            height: 3px;
            background: var(--text-main);
            margin: 5px 0;
            transition: 0.3s;
        }

        /* Hero Section (No Images allowed) */
        .hero-section {
            padding: 100px 0 120px 0;
            text-align: center;
            position: relative;
        }
        .hero-badge {
            display: inline-block;
            background: linear-gradient(135deg, rgba(79, 70, 229, 0.1), rgba(236, 72, 153, 0.1));
            color: var(--accent-color);
            padding: 6px 18px;
            border-radius: 50px;
            font-size: 0.85rem;
            font-weight: 600;
            margin-bottom: 25px;
            border: 1px solid rgba(124, 58, 237, 0.2);
        }
        .hero-title {
            font-size: 3rem;
            line-height: 1.2;
            margin-bottom: 25px;
            background: var(--primary-gradient);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }
        .hero-desc {
            font-size: 1.2rem;
            color: var(--text-muted);
            max-width: 800px;
            margin: 0 auto 40px auto;
        }
        .hero-btn-group {
            display: flex;
            justify-content: center;
            gap: 20px;
            flex-wrap: wrap;
        }
        .btn-primary {
            background: var(--primary-gradient);
            color: #fff;
            padding: 15px 35px;
            border-radius: 50px;
            text-decoration: none;
            font-weight: 700;
            font-size: 1.1rem;
            box-shadow: 0 8px 25px rgba(124, 58, 237, 0.35);
            transition: all 0.3s ease;
        }
        .btn-primary:hover {
            transform: translateY(-3px);
            box-shadow: 0 12px 30px rgba(124, 58, 237, 0.45);
        }
        .btn-secondary {
            background: #fff;
            color: var(--text-main);
            padding: 15px 35px;
            border-radius: 50px;
            text-decoration: none;
            font-weight: 700;
            font-size: 1.1rem;
            border: 2px solid var(--border-color);
            transition: all 0.3s ease;
        }
        .btn-secondary:hover {
            border-color: var(--accent-color);
            color: var(--accent-color);
            transform: translateY(-3px);
        }

        /* Section Layouts */
        section {
            padding: 80px 0;
            position: relative;
        }

        /* Data Indicators */
        .data-indicators {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
            gap: 25px;
            margin-top: -40px;
            margin-bottom: 40px;
        }
        .indicator-card {
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            padding: 30px;
            border-radius: 16px;
            text-align: center;
            box-shadow: 0 4px 20px rgba(0,0,0,0.02);
            transition: all 0.3s ease;
        }
        .indicator-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 12px 30px rgba(0,0,0,0.06);
            border-color: var(--accent-color);
        }
        .indicator-number {
            font-size: 2.5rem;
            font-weight: 800;
            background: var(--secondary-gradient);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            margin-bottom: 5px;
        }
        .indicator-label {
            font-size: 0.9rem;
            color: var(--text-muted);
            font-weight: 600;
        }

        /* Card grid styling */
        .card-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: 30px;
        }
        .service-card {
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            border-radius: 16px;
            padding: 30px;
            transition: all 0.3s ease;
            position: relative;
            overflow: hidden;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }
        .service-card::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            width: 4px;
            height: 100%;
            background: var(--primary-gradient);
            opacity: 0;
            transition: opacity 0.3s ease;
        }
        .service-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 15px 30px rgba(0,0,0,0.05);
            border-color: transparent;
        }
        .service-card:hover::before {
            opacity: 1;
        }
        .service-card h3 {
            font-size: 1.25rem;
            margin-bottom: 12px;
        }
        .service-card p {
            font-size: 0.9rem;
            color: var(--text-muted);
            margin-bottom: 20px;
        }
        .tag-cloud {
            display: flex;
            flex-wrap: wrap;
            gap: 8px;
        }
        .tag-item {
            background: var(--bg-light);
            padding: 4px 12px;
            border-radius: 20px;
            font-size: 0.75rem;
            font-weight: 600;
            color: var(--text-main);
            border: 1px solid var(--border-color);
        }

        /* Split layouts */
        .split-layout {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 50px;
            align-items: center;
        }
        .split-text h3 {
            font-size: 1.8rem;
            margin-bottom: 15px;
        }
        .split-text p {
            color: var(--text-muted);
            margin-bottom: 25px;
        }
        .feature-list {
            list-style: none;
        }
        .feature-list li {
            position: relative;
            padding-left: 25px;
            margin-bottom: 12px;
            font-size: 0.95rem;
            font-weight: 500;
        }
        .feature-list li::before {
            content: "✓";
            position: absolute;
            left: 0;
            color: #10b981;
            font-weight: bold;
        }
        .split-image-container {
            border-radius: 20px;
            overflow: hidden;
            box-shadow: 0 20px 40px rgba(0,0,0,0.1);
        }
        .split-image-container img {
            width: 100%;
            height: auto;
            display: block;
            transition: transform 0.5s ease;
        }
        .split-image-container:hover img {
            transform: scale(1.05);
        }

        /* Flow timeline steps */
        .timeline {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 20px;
            position: relative;
        }
        .timeline-step {
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            padding: 30px 20px;
            border-radius: 16px;
            text-align: center;
            position: relative;
            z-index: 1;
        }
        .step-number {
            width: 45px;
            height: 45px;
            background: var(--primary-gradient);
            color: #fff;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 800;
            margin: 0 auto 15px auto;
            box-shadow: 0 4px 10px rgba(124, 58, 237, 0.3);
        }
        .timeline-step h4 {
            font-size: 1.1rem;
            margin-bottom: 8px;
        }
        .timeline-step p {
            font-size: 0.85rem;
            color: var(--text-muted);
        }

        /* Tables & Evaluation styling */
        .table-responsive {
            width: 100%;
            overflow-x: auto;
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            border-radius: 16px;
            box-shadow: 0 10px 30px rgba(0,0,0,0.03);
        }
        table {
            width: 100%;
            border-collapse: collapse;
            text-align: left;
            font-size: 0.95rem;
        }
        th, td {
            padding: 16px 20px;
            border-bottom: 1px solid var(--border-color);
        }
        th {
            background-color: var(--bg-light);
            font-weight: 700;
            color: #0f172a;
        }
        tr:last-child td {
            border-bottom: none;
        }
        .rating-badge {
            background: var(--warm-gradient);
            color: #fff;
            padding: 4px 12px;
            border-radius: 20px;
            font-weight: 700;
            font-size: 0.85rem;
            display: inline-block;
        }
        .star-rating {
            color: #f59e0b;
            font-size: 1.1rem;
        }

        /* Accordion FAQ */
        .faq-wrapper {
            max-width: 800px;
            margin: 0 auto;
        }
        .faq-item {
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            border-radius: 12px;
            margin-bottom: 15px;
            overflow: hidden;
            transition: border-color 0.3s ease;
        }
        .faq-item.active {
            border-color: var(--accent-color);
        }
        .faq-header {
            padding: 20px;
            display: flex;
            justify-content: space-between;
            align-items: center;
            cursor: pointer;
            user-select: none;
            font-weight: 600;
            font-size: 1rem;
            color: #0f172a;
        }
        .faq-icon {
            font-size: 1.2rem;
            transition: transform 0.3s ease;
        }
        .faq-item.active .faq-icon {
            transform: rotate(45deg);
        }
        .faq-body {
            padding: 0 20px;
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.3s ease, padding 0.3s ease;
            font-size: 0.9rem;
            color: var(--text-muted);
            border-top: 1px solid transparent;
        }
        .faq-item.active .faq-body {
            padding: 20px;
            max-height: 200px;
            border-top: 1px solid var(--border-color);
        }

        /* Review Section Cards */
        .reviews-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 25px;
        }
        .review-card {
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            border-radius: 16px;
            padding: 30px;
            box-shadow: 0 4px 20px rgba(0,0,0,0.02);
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }
        .review-text {
            font-size: 0.95rem;
            color: var(--text-main);
            margin-bottom: 20px;
            font-style: italic;
        }
        .review-user-info {
            display: flex;
            align-items: center;
            gap: 12px;
        }
        .user-avatar-placeholder {
            width: 45px;
            height: 45px;
            border-radius: 50%;
            background: var(--primary-gradient);
            color: #fff;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 700;
        }
        .user-details h4 {
            font-size: 0.9rem;
            margin-bottom: 2px;
        }
        .user-details span {
            font-size: 0.8rem;
            color: var(--text-muted);
        }

        /* Article list */
        .article-card-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: 25px;
        }
        .article-card {
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            border-radius: 16px;
            overflow: hidden;
            display: flex;
            flex-direction: column;
            transition: all 0.3s ease;
        }
        .article-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 15px 30px rgba(0,0,0,0.05);
        }
        .article-content {
            padding: 20px;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
            flex-grow: 1;
        }
        .article-title {
            font-size: 1.05rem;
            margin-bottom: 12px;
            color: #0f172a;
            text-decoration: none;
            font-weight: 600;
            display: -webkit-box;
            -webkit-line-clamp: 2;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }
        .article-title:hover {
            color: var(--accent-color);
        }
        .article-meta {
            font-size: 0.8rem;
            color: var(--text-muted);
        }

        /* Form styling */
        .form-section-container {
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            border-radius: 24px;
            box-shadow: 0 20px 40px rgba(0,0,0,0.04);
            padding: 50px;
            max-width: 900px;
            margin: 0 auto;
        }
        .form-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 20px;
        }
        .form-group-full {
            grid-column: span 2;
        }
        .form-label {
            display: block;
            margin-bottom: 8px;
            font-weight: 600;
            font-size: 0.9rem;
        }
        .form-control {
            width: 100%;
            padding: 12px 16px;
            border: 1px solid var(--border-color);
            border-radius: 8px;
            background-color: var(--bg-light);
            font-size: 0.95rem;
            outline: none;
            transition: border-color 0.3s ease;
        }
        .form-control:focus {
            border-color: var(--accent-color);
        }
        textarea.form-control {
            resize: vertical;
            min-height: 120px;
        }
        .submit-btn {
            background: var(--primary-gradient);
            color: #fff;
            border: none;
            padding: 14px 35px;
            border-radius: 50px;
            font-size: 1rem;
            font-weight: 700;
            cursor: pointer;
            box-shadow: 0 8px 25px rgba(124, 58, 237, 0.3);
            transition: all 0.3s ease;
            width: 100%;
        }
        .submit-btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 12px 30px rgba(124, 58, 237, 0.4);
        }

        /* Footer styling */
        footer {
            background-color: #0f172a;
            color: #94a3b8;
            padding: 60px 0 30px 0;
            border-top: 1px solid #1e293b;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 40px;
            margin-bottom: 40px;
        }
        .footer-col h4 {
            color: #fff;
            font-size: 1.05rem;
            margin-bottom: 20px;
        }
        .footer-col p, .footer-col a {
            color: #94a3b8;
            text-decoration: none;
            font-size: 0.9rem;
            line-height: 1.8;
            display: block;
            margin-bottom: 8px;
        }
        .footer-col a:hover {
            color: #fff;
        }
        .footer-contact-qr {
            width: 120px;
            height: auto;
            border-radius: 8px;
            margin-top: 10px;
        }
        .friendship-links {
            border-top: 1px solid #1e293b;
            padding-top: 25px;
            margin-top: 20px;
            text-align: center;
        }
        .friendship-links h5 {
            color: #e2e8f0;
            margin-bottom: 12px;
            font-size: 0.9rem;
        }
        .friendship-links a {
            color: #94a3b8;
            text-decoration: none;
            margin: 0 10px;
            font-size: 0.85rem;
            display: inline-block;
        }
        .friendship-links a:hover {
            color: #fff;
        }
        .copyright-bar {
            border-top: 1px solid #1e293b;
            padding-top: 20px;
            text-align: center;
            font-size: 0.8rem;
        }

        /* Floating tools widget */
        .floating-widget {
            position: fixed;
            bottom: 40px;
            right: 25px;
            display: flex;
            flex-direction: column;
            gap: 12px;
            z-index: 999;
        }
        .widget-item {
            width: 48px;
            height: 48px;
            background: #fff;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            box-shadow: 0 8px 20px rgba(0,0,0,0.1);
            cursor: pointer;
            position: relative;
            transition: all 0.3s ease;
            text-decoration: none;
            color: var(--text-main);
        }
        .widget-item:hover {
            background: var(--primary-gradient);
            color: #fff;
            transform: translateY(-3px);
        }
        .widget-item svg {
            width: 22px;
            height: 22px;
            fill: currentColor;
        }
        .widget-dropdown {
            position: absolute;
            bottom: 60px;
            right: 0;
            background: #fff;
            border-radius: 12px;
            box-shadow: 0 10px 30px rgba(0,0,0,0.15);
            padding: 15px;
            width: 180px;
            opacity: 0;
            pointer-events: none;
            transform: translateY(10px);
            transition: all 0.3s ease;
            text-align: center;
            border: 1px solid var(--border-color);
        }
        .widget-item:hover .widget-dropdown {
            opacity: 1;
            pointer-events: auto;
            transform: translateY(0);
        }
        .widget-dropdown img {
            width: 100%;
            height: auto;
            border-radius: 6px;
        }
        .widget-dropdown p {
            color: var(--text-main);
            font-size: 0.8rem;
            margin-top: 8px;
            font-weight: 600;
        }

        /* Responsive Breakpoints */
        @media (max-width: 992px) {
            .split-layout {
                grid-template-columns: 1fr;
                gap: 30px;
            }
            .hero-title {
                font-size: 2.2rem;
            }
            .form-section-container {
                padding: 30px 20px;
            }
        }

        @media (max-width: 768px) {
            .mobile-toggle {
                display: block;
            }
            .nav-links {
                display: none;
                position: absolute;
                top: 70px;
                left: 0;
                width: 100%;
                background: #fff;
                flex-direction: column;
                padding: 20px;
                border-bottom: 1px solid var(--border-color);
                box-shadow: 0 10px 20px rgba(0,0,0,0.05);
            }
            .nav-links.active {
                display: flex;
            }
            .nav-dropdown:hover .dropdown-menu {
                position: relative;
                box-shadow: none;
                border: none;
                transform: none;
                opacity: 1;
                pointer-events: auto;
                left: 0;
                padding: 5px 0 5px 15px;
            }
            .form-grid {
                grid-template-columns: 1fr;
            }
            .form-group-full {
                grid-column: span 1;
            }
        }