:root {
      --primary-color: #6366f1;
      --secondary-color: #a855f7;
      --accent-color: #ec4899;
      --dark-text: #0f172a;
      --muted-text: #475569;
      --light-bg: #f8fafc;
      --card-bg: #ffffff;
      --border-color: #e2e8f0;
      --rainbow-gradient: linear-gradient(135deg, #6366f1 0%, #a855f7 33%, #ec4899 66%, #06b6d4 100%);
      --rainbow-subtle: linear-gradient(135deg, rgba(99, 102, 241, 0.05) 0%, rgba(168, 85, 247, 0.05) 50%, rgba(236, 72, 153, 0.05) 100%);
      --shadow-sm: 0 2px 8px rgba(15, 23, 42, 0.05);
      --shadow-md: 0 10px 25px -5px rgba(15, 23, 42, 0.08);
      --shadow-lg: 0 20px 30px -10px rgba(99, 102, 241, 0.15);
      --radius: 12px;
      --container-width: 1200px;
    }

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

    html {
      scroll-behavior: smooth;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
      background-color: var(--light-bg);
      color: var(--dark-text);
      line-height: 1.6;
    }

    body {
      overflow-x: hidden;
      background-color: var(--light-bg);
    }

    .container {
      width: 100%;
      max-width: var(--container-width);
      margin: 0 auto;
      padding: 0 20px;
    }

    /* Header & Nav */
    header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }

    .brand-group {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .ai-page-logo {
      height: 40px;
      width: auto;
      object-fit: contain;
    }

    .ai-page-home-link {
      font-weight: 600;
      color: var(--primary-color);
      text-decoration: none;
      font-size: 15px;
      padding: 6px 12px;
      background: rgba(99, 102, 241, 0.08);
      border-radius: 20px;
      transition: all 0.3s ease;
    }

    .ai-page-home-link:hover {
      background: var(--rainbow-gradient);
      color: #fff;
    }

    /* Required CSS constraint */
    .nav-links {
      display: flex;
      align-items: center;
      gap: 0;
      list-style: none;
    }

    .nav-links li a {
      color: var(--dark-text);
      text-decoration: none;
      font-size: 14px;
      font-weight: 500;
      padding: 8px 10px;
      white-space: nowrap;
      transition: color 0.3s ease;
    }

    .nav-links li a:hover {
      color: var(--secondary-color);
    }

    .nav-cta {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 10px 20px;
      border-radius: 30px;
      font-size: 14px;
      font-weight: 600;
      text-decoration: none;
      cursor: pointer;
      border: none;
      transition: all 0.3s ease;
      white-space: nowrap;
    }

    .btn-rainbow {
      background: var(--rainbow-gradient);
      color: #ffffff;
      box-shadow: 0 4px 15px rgba(168, 85, 247, 0.3);
    }

    .btn-rainbow:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 20px rgba(168, 85, 247, 0.4);
    }

    .btn-outline {
      background: #ffffff;
      color: var(--dark-text);
      border: 1px solid var(--border-color);
    }

    .btn-outline:hover {
      border-color: var(--secondary-color);
      color: var(--secondary-color);
      background: rgba(168, 85, 247, 0.05);
    }

    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 24px;
      color: var(--dark-text);
      cursor: pointer;
    }

    /* Sections Shared Styles */
    section {
      padding: 70px 0;
      position: relative;
    }

    .section-header {
      text-align: center;
      max-width: 800px;
      margin: 0 auto 50px auto;
    }

    .badge-rainbow {
      display: inline-block;
      padding: 4px 16px;
      border-radius: 20px;
      background: var(--rainbow-gradient);
      color: #ffffff;
      font-size: 12px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 1px;
      margin-bottom: 12px;
    }

    .section-title {
      font-size: 32px;
      font-weight: 800;
      color: var(--dark-text);
      margin-bottom: 12px;
      line-height: 1.3;
    }

    .section-subtitle {
      font-size: 16px;
      color: var(--muted-text);
    }

    /* Hero Section - STRICTLY NO IMAGES */
    .hero-section {
      padding: 90px 0 70px 0;
      background: var(--rainbow-subtle);
      border-bottom: 1px solid var(--border-color);
      text-align: center;
    }

    .hero-content {
      max-width: 900px;
      margin: 0 auto;
    }

    .hero-h1 {
      font-size: 36px;
      font-weight: 900;
      color: var(--dark-text);
      margin-bottom: 20px;
      line-height: 1.25;
      letter-spacing: -0.5px;
    }

    .hero-h1 span {
      background: var(--rainbow-gradient);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .hero-desc {
      font-size: 18px;
      color: var(--muted-text);
      margin-bottom: 35px;
      line-height: 1.7;
    }

    .hero-buttons {
      display: flex;
      justify-content: center;
      gap: 16px;
      margin-bottom: 50px;
      flex-wrap: wrap;
    }

    .hero-stats {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
      gap: 20px;
      margin-top: 40px;
    }

    .stat-card {
      background: var(--card-bg);
      padding: 24px 16px;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
      transition: transform 0.3s ease;
    }

    .stat-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-md);
    }

    .stat-number {
      font-size: 32px;
      font-weight: 800;
      background: var(--rainbow-gradient);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      margin-bottom: 6px;
    }

    .stat-label {
      font-size: 14px;
      color: var(--muted-text);
      font-weight: 500;
    }

    /* Cards Grid */
    .grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
    .grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
    .grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }

    .card {
      background: var(--card-bg);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      transition: all 0.3s ease;
      position: relative;
      overflow: hidden;
    }

    .card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-4px);
      border-color: var(--secondary-color);
    }

    .card-icon {
      width: 48px;
      height: 48px;
      border-radius: 10px;
      background: var(--rainbow-subtle);
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 22px;
      margin-bottom: 16px;
      border: 1px solid rgba(168, 85, 247, 0.2);
    }

    .card-title {
      font-size: 18px;
      font-weight: 700;
      color: var(--dark-text);
      margin-bottom: 10px;
    }

    .card-desc {
      font-size: 14px;
      color: var(--muted-text);
      line-height: 1.6;
    }

    /* Tags Cloud / Models List */
    .tag-container {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      margin-top: 15px;
    }

    .tag-item {
      background: #f1f5f9;
      color: var(--dark-text);
      padding: 6px 14px;
      border-radius: 20px;
      font-size: 13px;
      font-weight: 500;
      border: 1px solid var(--border-color);
      transition: all 0.2s;
    }

    .tag-item:hover {
      background: var(--rainbow-gradient);
      color: #fff;
      border-color: transparent;
    }

    /* Process steps */
    .process-steps {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
      gap: 20px;
      position: relative;
    }

    .step-card {
      background: var(--card-bg);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      position: relative;
    }

    .step-num {
      font-size: 36px;
      font-weight: 900;
      color: rgba(99, 102, 241, 0.2);
      position: absolute;
      top: 15px;
      right: 20px;
    }

    /* Rating & Compare Table */
    .compare-box {
      background: var(--card-bg);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 30px;
      box-shadow: var(--shadow-sm);
    }

    .rating-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding-bottom: 20px;
      border-bottom: 1px solid var(--border-color);
      margin-bottom: 24px;
      flex-wrap: wrap;
      gap: 16px;
    }

    .rating-score {
      display: flex;
      align-items: center;
      gap: 16px;
    }

    .score-big {
      font-size: 44px;
      font-weight: 900;
      color: var(--primary-color);
      line-height: 1;
    }

    .stars {
      color: #f59e0b;
      font-size: 20px;
    }

    .compare-table-wrapper {
      overflow-x: auto;
    }

    .compare-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
    }

    .compare-table th, .compare-table td {
      padding: 14px 16px;
      border-bottom: 1px solid var(--border-color);
      font-size: 14px;
    }

    .compare-table th {
      background: #f8fafc;
      font-weight: 700;
      color: var(--dark-text);
    }

    .highlight-col {
      background: rgba(99, 102, 241, 0.04);
      font-weight: 600;
      color: var(--primary-color);
    }

    /* FAQ Accordion */
    .faq-list {
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .faq-item {
      background: var(--card-bg);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      overflow: hidden;
    }

    .faq-question {
      width: 100%;
      text-align: left;
      padding: 18px 24px;
      background: none;
      border: none;
      font-size: 16px;
      font-weight: 700;
      color: var(--dark-text);
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
    }

    .faq-answer {
      padding: 0 24px 18px 24px;
      font-size: 14px;
      color: var(--muted-text);
      display: none;
      line-height: 1.6;
    }

    .faq-item.active .faq-answer {
      display: block;
    }

    .faq-item.active .faq-icon {
      transform: rotate(180deg);
    }

    .faq-icon {
      transition: transform 0.3s ease;
      font-size: 18px;
    }

    /* Review Cards */
    .review-card {
      background: var(--card-bg);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      box-shadow: var(--shadow-sm);
    }

    .review-user {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 14px;
    }

    .user-avatar {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: var(--rainbow-gradient);
      color: #fff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
    }

    .user-info h4 {
      font-size: 15px;
      color: var(--dark-text);
    }

    .user-info p {
      font-size: 12px;
      color: var(--muted-text);
    }

    /* Showcase & Banner Images Section */
    .showcase-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 20px;
    }

    .showcase-item {
      background: var(--card-bg);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      overflow: hidden;
    }

    .showcase-item img {
      width: 100%;
      height: auto;
      display: block;
      transition: transform 0.3s ease;
    }

    .showcase-item:hover img {
      transform: scale(1.03);
    }

    .showcase-info {
      padding: 16px;
    }

    /* Form Section */
    .form-wrapper {
      background: var(--card-bg);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 36px;
      box-shadow: var(--shadow-md);
      max-width: 700px;
      margin: 0 auto;
    }

    .form-group {
      margin-bottom: 20px;
    }

    .form-group label {
      display: block;
      font-size: 14px;
      font-weight: 600;
      margin-bottom: 8px;
      color: var(--dark-text);
    }

    .form-control {
      width: 100%;
      padding: 12px 16px;
      border: 1px solid var(--border-color);
      border-radius: 8px;
      font-size: 14px;
      background: #f8fafc;
      color: var(--dark-text);
      transition: border-color 0.3s ease;
    }

    .form-control:focus {
      outline: none;
      border-color: var(--primary-color);
      background: #ffffff;
    }

    textarea.form-control {
      resize: vertical;
      min-height: 120px;
    }

    /* Contact Details Grid */
    .contact-info-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
      gap: 20px;
      margin-top: 40px;
    }

    .contact-card {
      background: var(--card-bg);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 20px;
      text-align: center;
    }

    .qr-container img {
      width: 140px;
      height: 140px;
      object-fit: cover;
      border-radius: 8px;
      border: 1px solid var(--border-color);
    }

    /* Footer */
    footer {
      background: #ffffff;
      border-top: 1px solid var(--border-color);
      padding: 50px 0 30px 0;
      color: var(--dark-text);
    }

    .footer-content {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 40px;
      margin-bottom: 40px;
    }

    .footer-col h4 {
      font-size: 16px;
      font-weight: 700;
      margin-bottom: 16px;
      color: var(--dark-text);
    }

    .footer-links {
      list-style: none;
    }

    .footer-links li {
      margin-bottom: 8px;
    }

    .footer-links a {
      color: var(--muted-text);
      text-decoration: none;
      font-size: 14px;
      transition: color 0.2s;
    }

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

    .friend-links {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      padding-top: 20px;
      border-top: 1px solid var(--border-color);
      margin-bottom: 24px;
    }

    .friend-links a {
      color: var(--muted-text);
      text-decoration: none;
      font-size: 13px;
    }

    .friend-links a:hover {
      color: var(--secondary-color);
    }

    .copyright {
      text-align: center;
      color: var(--muted-text);
      font-size: 13px;
      padding-top: 20px;
      border-top: 1px solid var(--border-color);
    }

    /* Floating Customer Service */
    .float-kefu {
      position: fixed;
      right: 20px;
      bottom: 30px;
      z-index: 999;
      background: var(--card-bg);
      border: 1px solid var(--border-color);
      border-radius: 50px;
      padding: 10px 18px;
      box-shadow: var(--shadow-lg);
      display: flex;
      align-items: center;
      gap: 10px;
      text-decoration: none;
      color: var(--dark-text);
      font-weight: 600;
      font-size: 14px;
      transition: all 0.3s ease;
    }

    .float-kefu:hover {
      transform: translateY(-3px);
      box-shadow: 0 10px 25px rgba(99, 102, 241, 0.25);
    }

    .float-kefu-dot {
      width: 10px;
      height: 10px;
      border-radius: 50%;
      background: #10b981;
    }

    /* Responsive */
    @media (max-width: 1024px) {
      .grid-4 { grid-template-columns: repeat(2, 1fr); }
      .grid-3 { grid-template-columns: repeat(2, 1fr); }
      .footer-content { grid-template-columns: 1fr; }
    }

    @media (max-width: 768px) {
      .menu-toggle { display: block; }
      .nav-links-wrapper {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: #ffffff;
        border-bottom: 1px solid var(--border-color);
        padding: 20px;
        box-shadow: var(--shadow-md);
      }
      .nav-links-wrapper.active { display: block; }
      .nav-links {
        flex-direction: column;
        align-items: flex-start;
      }
      .nav-links li { width: 100%; }
      .nav-links li a {
        display: block;
        padding: 10px 0;
      }
      .nav-cta {
        margin-top: 15px;
        flex-direction: column;
        width: 100%;
      }
      .nav-cta .btn { width: 100%; }
      .hero-h1 { font-size: 26px; }
      .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
      .section-title { font-size: 24px; }
    }