/* CSS Root Variable Definitions - 缤纷糖果亮色风 */
    :root {
      --bg-main: #FAFAFD;
      --bg-card: #FFFFFF;
      --primary-color: #FF5E7E;
      --primary-hover: #E04867;
      --secondary-color: #6C5CE7;
      --accent-yellow: #FFD166;
      --accent-cyan: #00CEC9;
      --accent-purple: #A29BFE;
      --text-dark: #1E272E;
      --text-muted: #4B6584;
      --border-color: #F0F2F5;
      --shadow-sm: 0 4px 12px rgba(108, 92, 231, 0.08);
      --shadow-md: 0 10px 25px rgba(255, 94, 126, 0.12);
      --shadow-hover: 0 16px 35px rgba(108, 92, 231, 0.18);
      --radius-sm: 10px;
      --radius-md: 16px;
      --radius-lg: 24px;
      --container-width: 1240px;
      --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    }

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

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

    body {
      overflow-x: hidden;
      background: linear-gradient(180deg, #FFF6F8 0%, #FAFAFD 30%, #F4F5FB 100%);
    }

    a {
      color: var(--secondary-color);
      text-decoration: none;
      transition: var(--transition);
    }

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

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

    /* Section Component Structure */
    section {
      padding: 75px 0;
      position: relative;
    }

    .section-header {
      text-align: center;
      margin-bottom: 50px;
    }

    .section-tag {
      display: inline-block;
      padding: 6px 18px;
      background: linear-gradient(135deg, rgba(255, 94, 126, 0.1), rgba(108, 92, 231, 0.1));
      color: var(--primary-color);
      font-weight: 700;
      font-size: 0.9rem;
      border-radius: 50px;
      margin-bottom: 12px;
      border: 1px solid rgba(255, 94, 126, 0.2);
    }

    .section-title {
      font-size: 2.3rem;
      color: var(--text-dark);
      font-weight: 800;
      letter-spacing: -0.5px;
      margin-bottom: 12px;
    }

    .section-desc {
      font-size: 1.05rem;
      color: var(--text-muted);
      max-width: 720px;
      margin: 0 auto;
    }

    /* Modern Buttons */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 14px 32px;
      font-size: 1rem;
      font-weight: 700;
      border-radius: 50px;
      cursor: pointer;
      border: none;
      transition: var(--transition);
      box-shadow: var(--shadow-sm);
    }

    .btn-primary {
      background: linear-gradient(135deg, var(--primary-color), #FF8E53);
      color: #FFFFFF !important;
    }

    .btn-primary:hover {
      transform: translateY(-3px);
      box-shadow: var(--shadow-md);
      background: linear-gradient(135deg, var(--primary-hover), #FF7B39);
    }

    .btn-secondary {
      background: linear-gradient(135deg, var(--secondary-color), var(--accent-purple));
      color: #FFFFFF !important;
    }

    .btn-secondary:hover {
      transform: translateY(-3px);
      box-shadow: 0 10px 25px rgba(108, 92, 231, 0.3);
    }

    .btn-outline {
      background: #FFFFFF;
      color: var(--text-dark) !important;
      border: 2px solid var(--border-color);
    }

    .btn-outline:hover {
      border-color: var(--secondary-color);
      color: var(--secondary-color) !important;
      transform: translateY(-3px);
    }

    /* Header & Navigation (Rule: .nav-links gap must be 0) */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(15px);
      border-bottom: 1px solid rgba(240, 242, 245, 0.8);
      box-shadow: 0 4px 20px rgba(0, 0, 0, 0.03);
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 80px;
    }

    .brand-logo-area {
      display: flex;
      align-items: center;
      gap: 15px;
    }

    .ai-page-logo {
      height: 42px;
      width: auto;
      object-fit: contain;
    }

    .ai-page-home-link {
      font-weight: 700;
      font-size: 1rem;
      padding: 6px 14px;
      background: rgba(255, 94, 126, 0.08);
      color: var(--primary-color);
      border-radius: 20px;
    }

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

    .nav-links li a {
      display: block;
      padding: 10px 14px;
      font-size: 0.92rem;
      font-weight: 600;
      color: var(--text-dark);
      border-radius: 8px;
    }

    .nav-links li a:hover {
      color: var(--primary-color);
      background: rgba(255, 94, 126, 0.05);
    }

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

    .mobile-menu-btn {
      display: none;
      font-size: 1.5rem;
      background: none;
      border: none;
      cursor: pointer;
      color: var(--text-dark);
    }

    /* Hero Section (FIRST SCREEN - NO IMAGES ALLOWED) */
    .hero-section {
      padding: 90px 0 70px 0;
      background: radial-gradient(circle at 10% 20%, rgba(255, 209, 102, 0.15) 0%, transparent 40%),
                  radial-gradient(circle at 90% 80%, rgba(108, 92, 231, 0.15) 0%, transparent 40%),
                  radial-gradient(circle at 50% 50%, rgba(255, 94, 126, 0.1) 0%, transparent 60%);
      text-align: center;
      position: relative;
    }

    .hero-badge-group {
      display: flex;
      justify-content: center;
      flex-wrap: wrap;
      gap: 10px;
      margin-bottom: 24px;
    }

    .candy-tag {
      padding: 6px 16px;
      font-size: 0.85rem;
      font-weight: 700;
      border-radius: 30px;
      color: #2D3436;
      box-shadow: 0 4px 10px rgba(0,0,0,0.04);
    }
    .candy-tag-1 { background: #FFEAA7; }
    .candy-tag-2 { background: #74B9FF; color: #FFF; }
    .candy-tag-3 { background: #55E6C1; }
    .candy-tag-4 { background: #FD79A8; color: #FFF; }

    .hero-title {
      font-size: 2.8rem;
      font-weight: 900;
      line-height: 1.25;
      color: var(--text-dark);
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }

    .hero-subtitle {
      font-size: 1.2rem;
      color: var(--text-muted);
      max-width: 860px;
      margin: 0 auto 36px auto;
      line-height: 1.7;
    }

    .hero-cta-box {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 18px;
      margin-bottom: 55px;
      flex-wrap: wrap;
    }

    .hero-stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      max-width: 1000px;
      margin: 0 auto;
    }

    .stat-card {
      background: #FFFFFF;
      padding: 24px 15px;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-color);
      transition: var(--transition);
    }

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

    .stat-num {
      font-size: 2rem;
      font-weight: 900;
      color: var(--primary-color);
      margin-bottom: 4px;
    }

    .stat-label {
      font-size: 0.9rem;
      color: var(--text-muted);
      font-weight: 600;
    }

    /* Grid Layouts for Content */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
    }

    .grid-2 {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 30px;
    }

    /* Card Base */
    .candy-card {
      background: #FFFFFF;
      border-radius: var(--radius-md);
      padding: 30px;
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      position: relative;
      overflow: hidden;
    }

    .candy-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
      border-color: rgba(108, 92, 231, 0.3);
    }

    .card-icon-bubble {
      width: 54px;
      height: 54px;
      border-radius: 16px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.5rem;
      font-weight: bold;
      margin-bottom: 18px;
    }
    .bubble-pink { background: rgba(255, 94, 126, 0.12); color: var(--primary-color); }
    .bubble-purple { background: rgba(108, 92, 231, 0.12); color: var(--secondary-color); }
    .bubble-yellow { background: rgba(255, 209, 102, 0.25); color: #D68910; }
    .bubble-cyan { background: rgba(0, 206, 201, 0.15); color: #008B8B; }

    .card-title {
      font-size: 1.25rem;
      font-weight: 700;
      color: var(--text-dark);
      margin-bottom: 10px;
    }

    .card-text {
      font-size: 0.95rem;
      color: var(--text-muted);
      line-height: 1.6;
    }

    /* Model Cloud Matrix Tags */
    .model-tags-wrapper {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      justify-content: center;
      margin-top: 30px;
    }

    .model-tag-pill {
      background: #FFFFFF;
      padding: 10px 20px;
      border-radius: 30px;
      font-size: 0.92rem;
      font-weight: 700;
      color: var(--text-dark);
      border: 1px solid var(--border-color);
      box-shadow: 0 2px 8px rgba(0,0,0,0.03);
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .model-tag-pill span {
      width: 8px;
      height: 8px;
      border-radius: 50%;
      background: var(--primary-color);
    }

    /* Comparison Table Styling */
    .table-container {
      background: #FFFFFF;
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-md);
      overflow-x: auto;
      border: 1px solid var(--border-color);
    }

    .comp-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      min-width: 750px;
    }

    .comp-table th, .comp-table td {
      padding: 18px 24px;
      border-bottom: 1px solid var(--border-color);
    }

    .comp-table th {
      background: #F8F9FE;
      font-size: 1rem;
      font-weight: 800;
      color: var(--text-dark);
    }

    .comp-table tr:last-child td {
      border-bottom: none;
    }

    .highlight-cell {
      background: rgba(255, 94, 126, 0.04);
      font-weight: 700;
      color: var(--primary-color);
    }

    .rating-banner {
      background: linear-gradient(135deg, #FF6B6B, #6C5CE7);
      color: #FFFFFF;
      border-radius: var(--radius-md);
      padding: 30px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 30px;
      flex-wrap: wrap;
      gap: 20px;
    }

    .rating-score {
      font-size: 2.8rem;
      font-weight: 900;
      line-height: 1;
    }

    /* Process Workflow Steps */
    .process-steps {
      display: grid;
      grid-template-columns: repeat(5, 1fr);
      gap: 15px;
      position: relative;
    }

    .step-card {
      background: #FFFFFF;
      padding: 24px 16px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      text-align: center;
      box-shadow: var(--shadow-sm);
    }

    .step-num {
      width: 36px;
      height: 36px;
      border-radius: 50%;
      background: var(--primary-color);
      color: #FFF;
      font-weight: 800;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 14px auto;
    }

    /* FAQ Accordion */
    .faq-wrapper {
      max-width: 900px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 14px;
    }

    .faq-item {
      background: #FFFFFF;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }

    .faq-header {
      padding: 20px 24px;
      font-size: 1.05rem;
      font-weight: 700;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      background: #FFFFFF;
      user-select: none;
    }

    .faq-header:hover {
      color: var(--primary-color);
    }

    .faq-icon {
      font-weight: 900;
      font-size: 1.2rem;
      transition: transform 0.3s ease;
    }

    .faq-content {
      padding: 0 24px 20px 24px;
      font-size: 0.95rem;
      color: var(--text-muted);
      display: none;
      border-top: 1px dashed var(--border-color);
      margin-top: 5px;
      padding-top: 15px;
    }

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

    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }

    /* Testimonials Cards */
    .review-card {
      background: #FFFFFF;
      border-radius: var(--radius-md);
      padding: 28px;
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

    .reviewer-profile {
      display: flex;
      align-items: center;
      gap: 14px;
      margin-top: 18px;
    }

    .avatar-placeholder {
      width: 46px;
      height: 46px;
      border-radius: 50%;
      background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
      color: #FFF;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
    }

    /* Form Styles */
    .form-wrapper {
      background: #FFFFFF;
      border-radius: var(--radius-lg);
      padding: 40px;
      box-shadow: var(--shadow-md);
      border: 1px solid var(--border-color);
    }

    .form-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 20px;
    }

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

    .form-group.full-width {
      grid-column: span 2;
    }

    .form-group label {
      font-size: 0.92rem;
      font-weight: 700;
      color: var(--text-dark);
    }

    .form-control {
      padding: 14px 18px;
      border: 1.5px solid var(--border-color);
      border-radius: var(--radius-sm);
      font-size: 0.95rem;
      outline: none;
      transition: var(--transition);
    }

    .form-control:focus {
      border-color: var(--primary-color);
      box-shadow: 0 0 0 3px rgba(255, 94, 126, 0.15);
    }

    /* Footer Styling */
    .site-footer {
      background: #1E272E;
      color: #D2D7D9;
      padding: 60px 0 30px 0;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 40px;
      margin-bottom: 50px;
    }

    .footer-title {
      color: #FFFFFF;
      font-size: 1.1rem;
      font-weight: 700;
      margin-bottom: 20px;
    }

    .footer-links {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .footer-links a {
      color: #B2BEC3;
      font-size: 0.9rem;
    }

    .footer-links a:hover {
      color: #FFFFFF;
    }

    .friend-links-area {
      border-top: 1px solid #34495E;
      padding-top: 25px;
      margin-bottom: 30px;
      display: flex;
      flex-wrap: wrap;
      gap: 15px;
      align-items: center;
    }

    .friend-links-area a {
      color: #95A5A6;
      font-size: 0.88rem;
    }

    .friend-links-area a:hover {
      color: var(--accent-yellow);
    }

    .copyright-area {
      border-top: 1px solid #2C3E50;
      padding-top: 25px;
      text-align: center;
      font-size: 0.85rem;
      color: #7F8C8D;
    }

    /* Floating Customer Service Box */
    .floating-kefu {
      position: fixed;
      right: 25px;
      bottom: 25px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .kefu-btn {
      width: 54px;
      height: 54px;
      border-radius: 50%;
      background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
      color: #FFF;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 8px 20px rgba(0,0,0,0.2);
      cursor: pointer;
      font-size: 1.3rem;
      text-decoration: none;
    }

    /* Image Container Responsiveness */
    .ai-page-image {
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
      display: block;
    }

    /* Article Links Box */
    .articles-container {
      background: #FFFFFF;
      padding: 30px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
    }

    .article-item {
      padding: 12px 0;
      border-bottom: 1px solid var(--border-color);
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .article-item:last-child {
      border-bottom: none;
    }

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

    @media (max-width: 768px) {
      .hero-title { font-size: 2rem; }
      .hero-stats-grid { grid-template-columns: repeat(2, 1fr); }
      .grid-3, .grid-4, .grid-2 { grid-template-columns: 1fr; }
      .process-steps { grid-template-columns: 1fr; }
      .form-grid { grid-template-columns: 1fr; }
      .form-group.full-width { grid-column: span 1; }
      .mobile-menu-btn { display: block; }
      .nav-links {
        display: none;
        position: absolute;
        top: 80px;
        left: 0;
        width: 100%;
        background: #FFFFFF;
        flex-direction: column;
        padding: 20px;
        box-shadow: 0 10px 20px rgba(0,0,0,0.1);
      }
      .nav-links.active { display: flex; }
      .footer-grid { grid-template-columns: 1fr; }
    }