:root {
      --primary-cyan: #0fa3b1;
      --primary-teal: #008080;
      --accent-cyan: #2ceaa3;
      --bg-base: #f5faf9;
      --bg-surface: #ffffff;
      --bg-subtle: #ebf6f5;
      --border-subtle: #d3ebe7;
      --border-focus: #0fa3b1;
      --text-main: #132a2f;
      --text-muted: #4e6b70;
      --text-soft: #7a989d;
      --shadow-sm: 0 2px 8px rgba(15, 163, 177, 0.06);
      --shadow-md: 0 8px 24px rgba(15, 163, 177, 0.1);
      --shadow-lg: 0 16px 36px rgba(15, 163, 177, 0.14);
      --radius-sm: 6px;
      --radius-md: 12px;
      --radius-lg: 18px;
      --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
      background-color: var(--bg-base);
    }

    body {
      font-family: var(--font-stack);
      color: var(--text-main);
      background: radial-gradient(circle at 10% 20%, #eefbf9 0%, #f7fbfb 90%);
      line-height: 1.65;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

    a {
      color: inherit;
      text-decoration: none;
      transition: all 0.25s ease;
    }

    ul, ol {
      list-style: none;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

    .container {
      width: 100%;
      max-width: 1200px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 20px;
      padding-right: 20px;
    }

    .section {
      padding: 72px 0;
      position: relative;
    }

    .section-header {
      text-align: center;
      margin-bottom: 48px;
    }

    .section-badge {
      display: inline-block;
      padding: 5px 14px;
      background: rgba(15, 163, 177, 0.1);
      color: var(--primary-teal);
      border: 1px solid var(--border-subtle);
      border-radius: 20px;
      font-size: 0.85rem;
      font-weight: 600;
      margin-bottom: 12px;
      letter-spacing: 0.5px;
    }

    .section-title {
      font-size: 2.15rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 14px;
      line-height: 1.3;
    }

    .section-subtitle {
      font-size: 1rem;
      color: var(--text-muted);
      max-width: 640px;
      margin: 0 auto;
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 11px 26px;
      font-size: 0.95rem;
      font-weight: 600;
      border-radius: var(--radius-sm);
      cursor: pointer;
      transition: all 0.28s cubic-bezier(0.4, 0, 0.2, 1);
      border: 1px solid transparent;
      gap: 8px;
    }

    .btn-primary {
      background: linear-gradient(135deg, var(--primary-cyan) 0%, var(--primary-teal) 100%);
      color: #ffffff;
      box-shadow: 0 4px 14px rgba(15, 163, 177, 0.35);
    }

    .btn-primary:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 20px rgba(15, 163, 177, 0.45);
      background: linear-gradient(135deg, #11b3c3 0%, #008d8d 100%);
      color: #ffffff;
    }

    .btn-outline {
      background: var(--bg-surface);
      color: var(--primary-teal);
      border-color: var(--border-subtle);
    }

    .btn-outline:hover {
      background: var(--bg-subtle);
      border-color: var(--primary-cyan);
      transform: translateY(-2px);
    }

    .btn-accent {
      background: #112d32;
      color: #ffffff;
    }

    .btn-accent:hover {
      background: #000000;
      color: #ffffff;
      transform: translateY(-2px);
    }

    .site-header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-subtle);
      transition: all 0.3s ease;
    }

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

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

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

    .brand-text {
      font-size: 1.25rem;
      font-weight: 700;
      color: var(--primary-teal);
      letter-spacing: -0.5px;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 0;
    }

    .nav-links li a {
      font-size: 0.92rem;
      font-weight: 500;
      color: var(--text-main);
      padding: 8px 14px;
      border-radius: var(--radius-sm);
      transition: color 0.2s, background 0.2s;
    }

    .nav-links li a:hover {
      color: var(--primary-cyan);
      background: var(--bg-subtle);
    }

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

    .nav-toggle {
      display: none;
      background: none;
      border: 1px solid var(--border-subtle);
      padding: 8px;
      border-radius: var(--radius-sm);
      cursor: pointer;
    }

    .nav-toggle span {
      display: block;
      width: 22px;
      height: 2px;
      background: var(--text-main);
      margin: 4px 0;
      transition: 0.3s;
    }

    .hero-section {
      padding: 80px 0 60px;
      position: relative;
      background: linear-gradient(180deg, rgba(235, 246, 245, 0.6) 0%, rgba(245, 250, 249, 0) 100%);
    }

    .hero-wrapper {
      display: grid;
      grid-template-columns: 1fr;
      text-align: center;
      max-width: 900px;
      margin: 0 auto;
    }

    .hero-tag {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      background: #e3f5f3;
      color: var(--primary-teal);
      padding: 6px 16px;
      border-radius: 30px;
      font-size: 0.85rem;
      font-weight: 600;
      margin: 0 auto 20px;
      border: 1px solid #c2ece5;
    }

    .hero-title {
      font-size: 2.75rem;
      font-weight: 800;
      color: #0b2226;
      line-height: 1.25;
      letter-spacing: -1px;
      margin-bottom: 20px;
    }

    .hero-title span {
      background: linear-gradient(90deg, #0fa3b1 0%, #008080 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .hero-desc {
      font-size: 1.15rem;
      color: var(--text-muted);
      line-height: 1.7;
      margin-bottom: 34px;
      max-width: 760px;
      margin-left: auto;
      margin-right: auto;
    }

    .hero-actions {
      display: flex;
      justify-content: center;
      flex-wrap: wrap;
      gap: 16px;
      margin-bottom: 40px;
    }

    .hero-btn-official {
      padding: 13px 32px;
      font-size: 1.05rem;
      background: linear-gradient(135deg, #008080 0%, #0fa3b1 100%);
      color: #ffffff;
      font-weight: 700;
      border-radius: 30px;
      box-shadow: 0 8px 25px rgba(0, 128, 128, 0.35);
      animation: pulseHover 3s infinite alternate;
    }

    @keyframes pulseHover {
      0% { box-shadow: 0 4px 15px rgba(0, 128, 128, 0.3); }
      100% { box-shadow: 0 8px 28px rgba(15, 163, 177, 0.5); }
    }

    .hero-btn-official:hover {
      transform: translateY(-3px) scale(1.02);
      color: #ffffff;
    }

    .hero-stats {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 16px;
      background: var(--bg-surface);
      padding: 24px;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-subtle);
    }

    .stat-item {
      text-align: center;
      border-right: 1px solid var(--border-subtle);
    }

    .stat-item:last-child {
      border-right: none;
    }

    .stat-number {
      font-size: 1.6rem;
      font-weight: 800;
      color: var(--primary-teal);
      display: block;
      margin-bottom: 4px;
    }

    .stat-label {
      font-size: 0.85rem;
      color: var(--text-soft);
    }

    .grid-cards {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 24px;
    }

    .card {
      background: var(--bg-surface);
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-md);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      transition: all 0.3s ease;
      display: flex;
      flex-direction: column;
      position: relative;
    }

    .card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-md);
      border-color: var(--primary-cyan);
    }

    .card-icon {
      width: 48px;
      height: 48px;
      background: var(--bg-subtle);
      color: var(--primary-teal);
      border-radius: 10px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.3rem;
      margin-bottom: 18px;
    }

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

    .card-desc {
      font-size: 0.92rem;
      color: var(--text-muted);
      line-height: 1.6;
      flex-grow: 1;
    }

    .service-badge {
      display: inline-block;
      font-size: 0.75rem;
      background: #eef7f6;
      color: var(--primary-teal);
      padding: 2px 8px;
      border-radius: 4px;
      margin-bottom: 8px;
      width: fit-content;
      font-weight: 600;
    }

    .tag-cloud {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
      margin-top: 24px;
    }

    .tag-pill {
      background: var(--bg-surface);
      border: 1px solid var(--border-subtle);
      padding: 8px 16px;
      border-radius: 20px;
      font-size: 0.85rem;
      color: var(--text-muted);
      font-weight: 500;
      box-shadow: var(--shadow-sm);
      transition: all 0.2s;
    }

    .tag-pill:hover {
      border-color: var(--primary-cyan);
      color: var(--primary-teal);
      background: var(--bg-subtle);
    }

    .media-card {
      background: var(--bg-surface);
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: transform 0.3s;
    }

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

    .media-card-img {
      width: 100%;
      height: 200px;
      object-fit: cover;
      background-color: var(--bg-subtle);
    }

    .media-card-body {
      padding: 20px;
    }

    .banner-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
      gap: 16px;
      margin-top: 30px;
    }

    .banner-item {
      border-radius: var(--radius-md);
      overflow: hidden;
      border: 1px solid var(--border-subtle);
      box-shadow: var(--shadow-sm);
    }

    .banner-item img {
      width: 100%;
      height: 180px;
      object-fit: cover;
      transition: transform 0.3s;
    }

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

    .table-container {
      background: var(--bg-surface);
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-md);
      overflow-x: auto;
      box-shadow: var(--shadow-sm);
    }

    .custom-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      min-width: 680px;
    }

    .custom-table th,
    .custom-table td {
      padding: 16px 20px;
      border-bottom: 1px solid var(--border-subtle);
      font-size: 0.92rem;
    }

    .custom-table th {
      background: #f1f8f7;
      color: var(--text-main);
      font-weight: 700;
    }

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

    .custom-table tr:hover td {
      background: #fbfdfd;
    }

    .rating-badge {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      background: #fff8e6;
      color: #b78103;
      padding: 4px 10px;
      border-radius: 4px;
      font-weight: 700;
      font-size: 0.85rem;
    }

    .timeline {
      position: relative;
      max-width: 860px;
      margin: 0 auto;
    }

    .timeline-item {
      display: flex;
      gap: 24px;
      margin-bottom: 32px;
      position: relative;
    }

    .timeline-node {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: var(--primary-teal);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      flex-shrink: 0;
      box-shadow: 0 0 0 6px var(--bg-subtle);
    }

    .timeline-content {
      background: var(--bg-surface);
      border: 1px solid var(--border-subtle);
      padding: 20px 24px;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
      flex-grow: 1;
    }

    .timeline-title {
      font-size: 1.15rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 6px;
    }

    .timeline-desc {
      font-size: 0.92rem;
      color: var(--text-muted);
    }

    .faq-list {
      max-width: 840px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    .faq-item {
      background: var(--bg-surface);
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-sm);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: border-color 0.25s;
    }

    .faq-item:hover {
      border-color: var(--primary-cyan);
    }

    .faq-question {
      width: 100%;
      text-align: left;
      padding: 18px 22px;
      background: none;
      border: none;
      font-size: 1rem;
      font-weight: 600;
      color: var(--text-main);
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .faq-icon {
      font-size: 1.2rem;
      transition: transform 0.3s;
      color: var(--primary-teal);
    }

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

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      background: #fafdfd;
      border-top: 1px solid transparent;
    }

    .faq-item.active .faq-answer {
      border-top-color: var(--border-subtle);
      max-height: 240px;
    }

    .faq-answer-inner {
      padding: 18px 22px;
      font-size: 0.92rem;
      color: var(--text-muted);
      line-height: 1.7;
    }

    .reviews-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
      gap: 24px;
    }

    .review-card {
      background: var(--bg-surface);
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-md);
      padding: 24px;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

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

    .review-avatar {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: linear-gradient(135deg, #0fa3b1, #008080);
      color: #fff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
    }

    .review-meta h4 {
      font-size: 0.98rem;
      color: var(--text-main);
      font-weight: 600;
    }

    .review-meta p {
      font-size: 0.8rem;
      color: var(--text-soft);
    }

    .review-text {
      font-size: 0.92rem;
      color: var(--text-muted);
      line-height: 1.6;
      margin-bottom: 14px;
    }

    .review-stars {
      color: #f59e0b;
      font-size: 0.85rem;
    }

    .form-wrapper {
      max-width: 640px;
      margin: 0 auto;
      background: var(--bg-surface);
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-md);
      padding: 36px;
      box-shadow: var(--shadow-md);
    }

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

    .form-label {
      display: block;
      font-size: 0.9rem;
      font-weight: 600;
      color: var(--text-main);
      margin-bottom: 8px;
    }

    .form-control {
      width: 100%;
      padding: 12px 16px;
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-sm);
      font-size: 0.95rem;
      color: var(--text-main);
      background: #fafdfd;
      transition: border-color 0.2s, box-shadow 0.2s;
      outline: none;
    }

    .form-control:focus {
      border-color: var(--primary-cyan);
      box-shadow: 0 0 0 3px rgba(15, 163, 177, 0.15);
      background: #ffffff;
    }

    textarea.form-control {
      resize: vertical;
      min-height: 110px;
    }

    .articles-list {
      display: flex;
      flex-direction: column;
      gap: 12px;
      background: var(--bg-surface);
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-md);
      padding: 24px;
    }

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

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

    .article-link {
      font-size: 0.95rem;
      color: var(--text-main);
      font-weight: 500;
    }

    .article-link:hover {
      color: var(--primary-cyan);
      padding-left: 4px;
    }

    .article-date {
      font-size: 0.82rem;
      color: var(--text-soft);
    }

    .site-footer {
      background: #0f1d21;
      color: #e2e8f0;
      padding: 60px 0 30px;
      border-top: 1px solid #1c3238;
    }

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

    .footer-brand h3 {
      font-size: 1.3rem;
      color: #ffffff;
      margin-bottom: 12px;
    }

    .footer-brand p {
      font-size: 0.88rem;
      color: #94a3b8;
      line-height: 1.6;
      margin-bottom: 16px;
    }

    .footer-title {
      font-size: 1rem;
      color: #ffffff;
      margin-bottom: 16px;
      font-weight: 600;
    }

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

    .footer-links-list a {
      font-size: 0.88rem;
      color: #94a3b8;
    }

    .footer-links-list a:hover {
      color: var(--accent-cyan);
    }

    .contact-info-list li {
      font-size: 0.88rem;
      color: #94a3b8;
      margin-bottom: 8px;
    }

    .contact-qr-wrap {
      display: flex;
      align-items: center;
      gap: 16px;
      margin-top: 12px;
    }

    .contact-qr-wrap img {
      width: 90px;
      height: 90px;
      border-radius: var(--radius-sm);
      border: 1px solid rgba(255, 255, 255, 0.2);
    }

    .footer-bottom {
      border-top: 1px solid #1c3238;
      padding-top: 24px;
      text-align: center;
      font-size: 0.85rem;
      color: #64748b;
    }

    .friend-links-box {
      margin-bottom: 24px;
      padding-bottom: 20px;
      border-bottom: 1px solid #1c3238;
      font-size: 0.85rem;
      color: #94a3b8;
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      gap: 14px;
    }

    .friend-links-box a {
      color: #94a3b8;
    }

    .friend-links-box a:hover {
      color: var(--accent-cyan);
    }

    .float-widget {
      position: fixed;
      right: 20px;
      bottom: 30px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .float-btn {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: var(--bg-surface);
      border: 1px solid var(--border-subtle);
      box-shadow: var(--shadow-md);
      display: flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
      color: var(--primary-teal);
      font-weight: 700;
      transition: all 0.2s;
    }

    .float-btn:hover {
      background: var(--primary-teal);
      color: #ffffff;
      transform: scale(1.08);
    }

    .float-qr-pop {
      display: none;
      position: absolute;
      right: 56px;
      bottom: 0;
      background: #ffffff;
      padding: 12px;
      border-radius: var(--radius-sm);
      box-shadow: var(--shadow-lg);
      border: 1px solid var(--border-subtle);
      text-align: center;
      width: 140px;
    }

    .float-qr-pop img {
      width: 116px;
      height: 116px;
      margin: 0 auto 6px;
    }

    .float-qr-pop span {
      font-size: 0.75rem;
      color: var(--text-main);
    }

    .float-widget .float-kefu-btn:hover + .float-qr-pop,
    .float-qr-pop:hover {
      display: block;
    }

    @media (max-width: 992px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      .nav-links {
        display: none;
      }
      .nav-links.active {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: #ffffff;
        border-bottom: 1px solid var(--border-subtle);
        padding: 20px;
        box-shadow: var(--shadow-md);
      }
      .nav-toggle {
        display: block;
      }
      .hero-title {
        font-size: 2.15rem;
      }
      .hero-stats {
        grid-template-columns: repeat(2, 1fr);
        row-gap: 20px;
      }
      .stat-item:nth-child(2) {
        border-right: none;
      }
    }

    @media (max-width: 640px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .hero-title {
        font-size: 1.85rem;
      }
      .hero-stats {
        grid-template-columns: 1fr;
      }
      .stat-item {
        border-right: none;
        border-bottom: 1px solid var(--border-subtle);
        padding-bottom: 12px;
      }
      .stat-item:last-child {
        border-bottom: none;
      }
      .form-wrapper {
        padding: 20px;
      }
    }