:root {
      --primary: #2563eb;
      --primary-light: #3b82f6;
      --primary-dark: #1d4ed8;
      --accent: #f97316;
      --accent-soft: #fff7ed;
      --bg-main: #f8fafc;
      --bg-card: #ffffff;
      --bg-alt: #f1f5f9;
      --text-main: #0f172a;
      --text-muted: #475569;
      --text-light: #64748b;
      --border-color: #e2e8f0;
      --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
      --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
      --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -4px rgba(0, 0, 0, 0.04);
      --radius: 12px;
      --transition: all 0.25s ease-in-out;
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      background-color: var(--bg-main);
      color: var(--text-main);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    a {
      color: inherit;
      text-decoration: none;
      transition: var(--transition);
    }
    .container {
      width: 100%;
      max-width: 1200px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 20px;
      padding-right: 20px;
    }
    .header-nav {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(255, 255, 255, 0.95);
      backdrop-filter: blur(8px);
      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-area {
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .ai-page-logo {
      height: 38px;
      width: auto;
      object-fit: contain;
      display: block;
    }
    .brand-text {
      font-size: 18px;
      font-weight: 700;
      color: var(--text-main);
    }
    .nav-menu {
      display: flex;
      align-items: center;
    }
    .nav-links {
      display: flex;
      align-items: center;
      list-style: none;
      gap: 0;
    }
    .nav-links li a {
      display: block;
      padding: 8px 12px;
      font-size: 14px;
      font-weight: 500;
      color: var(--text-muted);
      border-radius: 6px;
    }
    .nav-links li a:hover,
    .nav-links li a.active {
      color: var(--primary);
      background-color: #eff6ff;
    }
    .nav-actions {
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 10px 20px;
      font-size: 14px;
      font-weight: 600;
      border-radius: 8px;
      cursor: pointer;
      border: 1px solid transparent;
      transition: var(--transition);
      text-align: center;
    }
    .btn-primary {
      background-color: var(--primary);
      color: #ffffff;
      box-shadow: 0 2px 4px rgba(37, 99, 235, 0.2);
    }
    .btn-primary:hover {
      background-color: var(--primary-dark);
      transform: translateY(-1px);
    }
    .btn-accent {
      background-color: var(--accent);
      color: #ffffff;
      box-shadow: 0 2px 4px rgba(249, 115, 22, 0.25);
    }
    .btn-accent:hover {
      background-color: #ea580c;
      transform: translateY(-1px);
    }
    .btn-outline {
      background-color: #ffffff;
      border-color: var(--border-color);
      color: var(--text-main);
    }
    .btn-outline:hover {
      border-color: var(--primary);
      color: var(--primary);
      background-color: #f8fafc;
    }
    .menu-toggle {
      display: none;
      background: none;
      border: none;
      cursor: pointer;
      padding: 6px;
    }
    .menu-toggle span {
      display: block;
      width: 24px;
      height: 2px;
      background-color: var(--text-main);
      margin: 5px 0;
      transition: var(--transition);
    }
    .hero-section {
      background: linear-gradient(180deg, #eff6ff 0%, #ffffff 100%);
      padding: 80px 0 60px;
      border-bottom: 1px solid var(--border-color);
      text-align: center;
      position: relative;
    }
    .hero-tag {
      display: inline-flex;
      align-items: center;
      padding: 6px 16px;
      background-color: #dbeafe;
      color: var(--primary-dark);
      font-size: 13px;
      font-weight: 600;
      border-radius: 9999px;
      margin-bottom: 24px;
      border: 1px solid #bfdbfe;
    }
    .hero-title {
      font-size: 38px;
      line-height: 1.3;
      font-weight: 800;
      color: var(--text-main);
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }
    .hero-desc {
      font-size: 18px;
      color: var(--text-muted);
      max-width: 820px;
      margin: 0 auto 36px;
      line-height: 1.7;
    }
    .hero-buttons {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 16px;
      flex-wrap: wrap;
      margin-bottom: 48px;
    }
    .hero-stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      max-width: 980px;
      margin: 0 auto;
      text-align: left;
    }
    .stat-card {
      background: #ffffff;
      padding: 20px;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }
    .stat-card-title {
      font-size: 13px;
      color: var(--text-light);
      margin-bottom: 6px;
    }
    .stat-card-val {
      font-size: 24px;
      font-weight: 700;
      color: var(--primary);
    }
    .stat-card-sub {
      font-size: 12px;
      color: var(--text-muted);
      margin-top: 4px;
    }
    section {
      padding: 70px 0;
      border-bottom: 1px solid var(--border-color);
      background-color: #ffffff;
    }
    section:nth-of-type(even) {
      background-color: var(--bg-main);
    }
    .section-header {
      text-align: center;
      max-width: 760px;
      margin: 0 auto 48px;
    }
    .section-subtitle {
      font-size: 13px;
      font-weight: 700;
      text-transform: uppercase;
      color: var(--primary);
      letter-spacing: 1px;
      margin-bottom: 8px;
      display: block;
    }
    .section-title {
      font-size: 30px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 14px;
      line-height: 1.35;
    }
    .section-desc {
      font-size: 15px;
      color: var(--text-muted);
      line-height: 1.65;
    }
    .grid-2 {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
      align-items: stretch;
    }
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      align-items: stretch;
    }
    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      align-items: stretch;
    }
    .card {
      background-color: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      transition: var(--transition);
    }
    .card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-2px);
      border-color: #cbd5e1;
    }
    .card-icon {
      width: 44px;
      height: 44px;
      border-radius: 10px;
      background-color: #eff6ff;
      color: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 18px;
      margin-bottom: 16px;
    }
    .card-title {
      font-size: 18px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 10px;
    }
    .card-text {
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.6;
      flex-grow: 1;
    }
    .card-footer-info {
      margin-top: 16px;
      padding-top: 12px;
      border-top: 1px dashed var(--border-color);
      font-size: 12px;
      color: var(--text-light);
      display: flex;
      justify-content: space-between;
    }
    .model-tags-wrap {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
      margin-top: 20px;
    }
    .model-tag {
      padding: 6px 12px;
      background: #f1f5f9;
      border-radius: 6px;
      font-size: 13px;
      color: var(--text-main);
      border: 1px solid #e2e8f0;
      font-weight: 500;
    }
    .media-card {
      overflow: hidden;
      padding: 0;
    }
    .media-box {
      width: 100%;
      height: 200px;
      overflow: hidden;
      background: #e2e8f0;
    }
    .media-box img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
      transition: var(--transition);
    }
    .media-card:hover .media-box img {
      transform: scale(1.03);
    }
    .media-content {
      padding: 20px;
      display: flex;
      flex-direction: column;
      flex-grow: 1;
    }
    .step-list {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
    }
    .step-item {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 24px 20px;
      position: relative;
    }
    .step-number {
      font-size: 32px;
      font-weight: 800;
      color: #bfdbfe;
      line-height: 1;
      margin-bottom: 12px;
    }
    .step-title {
      font-size: 16px;
      font-weight: 700;
      margin-bottom: 8px;
    }
    .step-desc {
      font-size: 13px;
      color: var(--text-muted);
    }
    .table-container {
      width: 100%;
      overflow-x: auto;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      box-shadow: var(--shadow-sm);
    }
    .custom-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      font-size: 14px;
    }
    .custom-table th,
    .custom-table td {
      padding: 16px 20px;
      border-bottom: 1px solid var(--border-color);
      vertical-align: middle;
    }
    .custom-table th {
      background-color: #f8fafc;
      font-weight: 700;
      color: var(--text-main);
    }
    .custom-table tr:last-child td {
      border-bottom: none;
    }
    .custom-table .highlight-col {
      background-color: #f0fdf4;
      font-weight: 600;
      color: #166534;
    }
    .rating-banner {
      background: linear-gradient(135deg, #1e293b 0%, #0f172a 100%);
      color: #ffffff;
      padding: 28px 32px;
      border-radius: var(--radius);
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 32px;
      flex-wrap: wrap;
      gap: 20px;
    }
    .rating-title {
      font-size: 20px;
      font-weight: 700;
      color: #ffffff;
      margin-bottom: 4px;
    }
    .rating-subtitle {
      font-size: 14px;
      color: #94a3b8;
    }
    .rating-score-box {
      display: flex;
      align-items: baseline;
      gap: 8px;
    }
    .score-number {
      font-size: 36px;
      font-weight: 800;
      color: #38bdf8;
    }
    .score-max {
      font-size: 16px;
      color: #94a3b8;
    }
    .stars {
      color: #f59e0b;
      font-size: 18px;
      letter-spacing: 2px;
    }
    .faq-list {
      max-width: 900px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 14px;
    }
    .faq-item {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      overflow: hidden;
      transition: var(--transition);
    }
    .faq-item.active {
      border-color: #93c5fd;
      box-shadow: var(--shadow-sm);
    }
    .faq-question {
      padding: 18px 24px;
      font-size: 16px;
      font-weight: 600;
      color: var(--text-main);
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: space-between;
      user-select: none;
    }
    .faq-icon {
      font-size: 18px;
      color: var(--text-light);
      transition: transform 0.25s ease;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
      color: var(--primary);
    }
    .faq-answer {
      display: none;
      padding: 0 24px 18px;
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.65;
    }
    .faq-item.active .faq-answer {
      display: block;
    }
    .review-header {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 12px;
    }
    .avatar-placeholder {
      width: 42px;
      height: 42px;
      border-radius: 50%;
      background-color: #e0e7ff;
      color: #4338ca;
      font-weight: 700;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 15px;
    }
    .user-info-name {
      font-size: 15px;
      font-weight: 700;
      color: var(--text-main);
    }
    .user-info-role {
      font-size: 12px;
      color: var(--text-light);
    }
    .review-body {
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.6;
      font-style: italic;
    }
    .form-container {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 36px;
      box-shadow: var(--shadow-md);
    }
    .form-group {
      margin-bottom: 20px;
    }
    .form-group label {
      display: block;
      font-size: 14px;
      font-weight: 600;
      color: var(--text-main);
      margin-bottom: 6px;
    }
    .form-input,
    .form-select,
    .form-textarea {
      width: 100%;
      padding: 12px 14px;
      font-size: 14px;
      border: 1px solid var(--border-color);
      border-radius: 8px;
      background-color: #f8fafc;
      color: var(--text-main);
      outline: none;
      transition: var(--transition);
      font-family: inherit;
    }
    .form-input:focus,
    .form-select:focus,
    .form-textarea:focus {
      border-color: var(--primary);
      background-color: #ffffff;
      box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
    }
    .form-textarea {
      resize: vertical;
      min-height: 110px;
    }
    .article-list {
      display: flex;
      flex-direction: column;
      gap: 12px;
    }
    .article-item {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 14px 18px;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 8px;
      transition: var(--transition);
    }
    .article-item:hover {
      border-color: var(--primary);
      background-color: #f8fafc;
    }
    .article-title {
      font-size: 14px;
      font-weight: 600;
      color: var(--text-main);
    }
    .article-tag {
      font-size: 12px;
      color: var(--primary);
      background: #eff6ff;
      padding: 3px 8px;
      border-radius: 4px;
    }
    .footer-section {
      background-color: #0f172a;
      color: #94a3b8;
      padding: 60px 0 24px;
      border-top: 1px solid #1e293b;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 40px;
      margin-bottom: 40px;
    }
    .footer-col h4 {
      color: #f8fafc;
      font-size: 15px;
      font-weight: 700;
      margin-bottom: 18px;
    }
    .footer-links {
      list-style: none;
    }
    .footer-links li {
      margin-bottom: 10px;
    }
    .footer-links a {
      color: #94a3b8;
      font-size: 13px;
    }
    .footer-links a:hover {
      color: #ffffff;
    }
    .footer-qr-card {
      display: flex;
      flex-direction: column;
      align-items: flex-start;
      gap: 10px;
    }
    .footer-qr-card img {
      width: 105px;
      height: 105px;
      border-radius: 6px;
      border: 2px solid #334155;
      background: #ffffff;
    }
    .footer-friend-links {
      padding: 24px 0;
      border-top: 1px solid #1e293b;
      border-bottom: 1px solid #1e293b;
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      gap: 14px;
      font-size: 13px;
    }
    .footer-friend-links span {
      color: #f8fafc;
      font-weight: 600;
    }
    .footer-friend-links a {
      color: #94a3b8;
    }
    .footer-friend-links a:hover {
      color: #ffffff;
    }
    .footer-bottom {
      padding-top: 24px;
      text-align: center;
      font-size: 12px;
      color: #64748b;
    }
    .floating-service {
      position: fixed;
      right: 20px;
      bottom: 25px;
      z-index: 99;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }
    .float-btn {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background-color: var(--primary);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
      cursor: pointer;
      border: none;
      transition: var(--transition);
      font-size: 13px;
      font-weight: 700;
      text-align: center;
    }
    .float-btn:hover {
      transform: scale(1.08);
      background-color: var(--primary-dark);
    }
    .float-qr-panel {
      position: absolute;
      right: 58px;
      bottom: 0;
      background: #ffffff;
      padding: 14px;
      border-radius: var(--radius);
      box-shadow: var(--shadow-lg);
      border: 1px solid var(--border-color);
      display: none;
      flex-direction: column;
      align-items: center;
      width: 140px;
      text-align: center;
    }
    .float-qr-panel img {
      width: 110px;
      height: 110px;
      margin-bottom: 6px;
    }
    .float-qr-panel span {
      font-size: 12px;
      color: var(--text-main);
      font-weight: 600;
    }
    .floating-service:hover .float-qr-panel {
      display: flex;
    }
    @media (max-width: 992px) {
      .grid-4, .grid-3 {
        grid-template-columns: repeat(2, 1fr);
      }
      .step-list {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      .hero-stats-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 768px) {
      .menu-toggle {
        display: block;
      }
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #ffffff;
        flex-direction: column;
        padding: 16px 20px;
        border-bottom: 1px solid var(--border-color);
        box-shadow: var(--shadow-md);
      }
      .nav-links.active {
        display: flex;
      }
      .nav-links li {
        width: 100%;
      }
      .nav-links li a {
        padding: 10px 0;
      }
      .grid-2, .grid-3, .grid-4 {
        grid-template-columns: 1fr;
      }
      .step-list {
        grid-template-columns: 1fr;
      }
      .hero-stats-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .hero-title {
        font-size: 26px;
      }
      .section-title {
        font-size: 24px;
      }
      .rating-banner {
        flex-direction: column;
        align-items: flex-start;
      }
    }