:root {
      --primary: #d32f2f;
      --primary-dark: #b71c1c;
      --primary-light: #ffebee;
      --accent: #ff5252;
      --accent-warm: #ff7961;
      --text-main: #1f2429;
      --text-muted: #5c6470;
      --bg-light: #fbfbfc;
      --bg-card: #ffffff;
      --border-color: #f0d8d8;
      --border-light: #f5e4e4;
      --shadow-sm: 0 4px 12px rgba(211, 47, 47, 0.06);
      --shadow-md: 0 10px 28px rgba(211, 47, 47, 0.1);
      --radius: 12px;
      --transition: all 0.28s ease-in-out;
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      background-color: var(--bg-light);
      color: var(--text-main);
      line-height: 1.65;
      overflow-x: hidden;
    }

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

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

    .container {
      width: 100%;
      max-width: 1240px;
      margin: 0 auto;
      padding: 0 20px;
    }

    /* Header & Navigation */
    .header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(255, 255, 255, 0.96);
      backdrop-filter: blur(10px);
      border-bottom: 1px solid var(--border-light);
      box-shadow: var(--shadow-sm);
    }

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

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

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

    .brand-title {
      font-size: 1.3rem;
      font-weight: 800;
      color: var(--primary);
      letter-spacing: -0.5px;
    }

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

    .nav-links li a {
      font-size: 0.94rem;
      font-weight: 600;
      color: var(--text-main);
      padding: 8px 12px;
      border-radius: 6px;
      transition: var(--transition);
    }

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

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

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 10px 22px;
      font-size: 0.95rem;
      font-weight: 600;
      border-radius: 8px;
      cursor: pointer;
      border: 1px solid transparent;
      transition: var(--transition);
      text-align: center;
    }

    .btn-primary {
      background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
      color: #ffffff !important;
      box-shadow: 0 4px 14px rgba(211, 47, 47, 0.3);
    }

    .btn-primary:hover {
      background: linear-gradient(135deg, var(--accent) 0%, var(--primary) 100%);
      transform: translateY(-2px);
      box-shadow: 0 6px 18px rgba(211, 47, 47, 0.4);
    }

    .btn-outline {
      background: #ffffff;
      color: var(--primary) !important;
      border-color: var(--primary);
    }

    .btn-outline:hover {
      background: var(--primary-light);
      border-color: var(--primary-dark);
    }

    .btn-large {
      padding: 14px 32px;
      font-size: 1.05rem;
    }

    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.6rem;
      color: var(--text-main);
      cursor: pointer;
    }

    /* Hero Section (No Images Allowed) */
    .hero-section {
      position: relative;
      background: linear-gradient(180deg, #fff7f7 0%, #ffffff 100%);
      padding: 84px 0 64px 0;
      border-bottom: 1px solid var(--border-light);
      text-align: center;
      overflow: hidden;
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      background: #ffe8e8;
      color: var(--primary);
      padding: 6px 16px;
      border-radius: 30px;
      font-size: 0.88rem;
      font-weight: 700;
      margin-bottom: 24px;
      border: 1px solid #ffd0d0;
    }

    .hero-title {
      font-size: 2.7rem;
      font-weight: 900;
      line-height: 1.25;
      color: #1a1a1a;
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }

    .hero-title span {
      color: var(--primary);
    }

    .hero-subtitle {
      max-width: 820px;
      margin: 0 auto 36px;
      font-size: 1.12rem;
      color: var(--text-muted);
      line-height: 1.7;
    }

    .hero-cta-group {
      display: flex;
      justify-content: center;
      align-items: center;
      gap: 16px;
      flex-wrap: wrap;
      margin-bottom: 48px;
    }

    .hero-metrics {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      max-width: 1040px;
      margin: 0 auto;
    }

    .metric-card {
      background: #ffffff;
      padding: 24px 16px;
      border-radius: var(--radius);
      border: 1px solid var(--border-light);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }

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

    .metric-value {
      font-size: 2rem;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 6px;
    }

    .metric-label {
      font-size: 0.9rem;
      color: var(--text-muted);
      font-weight: 500;
    }

    /* Section Styles */
    .section-block {
      padding: 80px 0;
      border-bottom: 1px solid #f2e6e6;
    }

    .section-header {
      text-align: center;
      max-width: 760px;
      margin: 0 auto 52px;
    }

    .section-tag {
      display: inline-block;
      color: var(--primary);
      font-size: 0.85rem;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 1px;
      margin-bottom: 10px;
    }

    .section-title {
      font-size: 2.1rem;
      font-weight: 800;
      color: #1a1a1a;
      margin-bottom: 14px;
    }

    .section-desc {
      font-size: 1.02rem;
      color: var(--text-muted);
      line-height: 1.65;
    }

    /* Grid Layouts */
    .grid-2 {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 32px;
      align-items: center;
    }

    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

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

    /* Cards */
    .card {
      background: var(--bg-card);
      border-radius: var(--radius);
      border: 1px solid var(--border-light);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
    }

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

    .card-icon {
      width: 48px;
      height: 48px;
      border-radius: 10px;
      background: var(--primary-light);
      color: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.4rem;
      margin-bottom: 18px;
      font-weight: 800;
    }

    .card-title {
      font-size: 1.2rem;
      font-weight: 700;
      color: #1a1a1a;
      margin-bottom: 12px;
    }

    .card-text {
      font-size: 0.94rem;
      color: var(--text-muted);
      line-height: 1.6;
      flex-grow: 1;
    }

    /* Model Tag Cloud */
    .tag-cloud {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
      margin-top: 32px;
    }

    .tag-item {
      background: #ffffff;
      border: 1px solid var(--border-light);
      padding: 8px 18px;
      border-radius: 24px;
      font-size: 0.9rem;
      font-weight: 600;
      color: var(--text-main);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }

    .tag-item:hover {
      background: var(--primary);
      color: #ffffff;
      border-color: var(--primary);
      transform: translateY(-2px);
    }

    /* Process Flow */
    .process-steps {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      position: relative;
    }

    .step-box {
      background: #ffffff;
      padding: 28px 20px;
      border-radius: var(--radius);
      border: 1px solid var(--border-light);
      text-align: center;
      position: relative;
    }

    .step-number {
      width: 36px;
      height: 36px;
      border-radius: 50%;
      background: var(--primary);
      color: #ffffff;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      margin-bottom: 16px;
    }

    .step-title {
      font-size: 1.1rem;
      font-weight: 700;
      margin-bottom: 10px;
    }

    .step-desc {
      font-size: 0.88rem;
      color: var(--text-muted);
    }

    /* Rating & Review */
    .rating-banner {
      background: linear-gradient(135deg, #b71c1c 0%, #d32f2f 100%);
      color: #ffffff;
      border-radius: var(--radius);
      padding: 40px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 40px;
      box-shadow: var(--shadow-md);
    }

    .rating-score {
      font-size: 3.4rem;
      font-weight: 900;
      line-height: 1;
    }

    .rating-stars {
      color: #ffd700;
      font-size: 1.4rem;
      margin-top: 6px;
    }

    .rating-info h3 {
      font-size: 1.6rem;
      margin-bottom: 8px;
    }

    .rating-info p {
      opacity: 0.9;
      font-size: 0.98rem;
    }

    /* Comparison Table */
    .table-container {
      overflow-x: auto;
      background: #ffffff;
      border-radius: var(--radius);
      border: 1px solid var(--border-light);
      box-shadow: var(--shadow-sm);
    }

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

    .custom-table th, .custom-table td {
      padding: 16px 20px;
      border-bottom: 1px solid #f2e6e6;
      font-size: 0.94rem;
    }

    .custom-table th {
      background: #fff3f3;
      color: var(--primary-dark);
      font-weight: 700;
    }

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

    .custom-table .highlight-col {
      background: #fff8f8;
      font-weight: 700;
      color: var(--primary-dark);
    }

    /* FAQ Accordion */
    .faq-list {
      max-width: 960px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 14px;
    }

    .faq-item {
      background: #ffffff;
      border-radius: 8px;
      border: 1px solid var(--border-light);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }

    .faq-question {
      padding: 18px 24px;
      font-weight: 700;
      font-size: 1.02rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      user-select: none;
      background: #ffffff;
      color: var(--text-main);
    }

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

    .faq-icon {
      font-size: 1.2rem;
      transition: transform 0.28s ease;
      color: var(--primary);
    }

    .faq-answer {
      padding: 0 24px;
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      font-size: 0.94rem;
      color: var(--text-muted);
      background: #fffdfd;
      line-height: 1.7;
    }

    .faq-item.active .faq-answer {
      padding: 16px 24px 22px;
      max-height: 300px;
      border-top: 1px solid #fcedec;
    }

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

    /* Form Section */
    .form-wrapper {
      background: #ffffff;
      border-radius: var(--radius);
      border: 1px solid var(--border-light);
      box-shadow: var(--shadow-md);
      padding: 40px;
      max-width: 800px;
      margin: 0 auto;
    }

    .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: 600;
      color: var(--text-main);
    }

    .form-control {
      padding: 12px 16px;
      border: 1px solid #dcd1d1;
      border-radius: 8px;
      font-size: 0.95rem;
      outline: none;
      transition: var(--transition);
      background: #fdfbfb;
      font-family: inherit;
    }

    .form-control:focus {
      border-color: var(--primary);
      background: #ffffff;
      box-shadow: 0 0 0 3px rgba(211, 47, 47, 0.12);
    }

    /* Contact Card Area */
    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
      margin-top: 40px;
    }

    .contact-info-card {
      background: #ffffff;
      border: 1px solid var(--border-light);
      border-radius: var(--radius);
      padding: 32px;
      box-shadow: var(--shadow-sm);
    }

    .contact-item {
      display: flex;
      align-items: center;
      gap: 16px;
      margin-bottom: 20px;
    }

    .contact-qr {
      text-align: center;
      padding: 20px;
      background: #fff8f8;
      border-radius: 8px;
      border: 1px dashed var(--accent-warm);
    }

    .contact-qr img {
      width: 140px;
      height: 140px;
      margin: 0 auto 10px;
      border-radius: 6px;
      object-fit: contain;
      background: #fff;
    }

    /* Articles */
    .article-links-box {
      background: #ffffff;
      padding: 24px;
      border-radius: var(--radius);
      border: 1px solid var(--border-light);
      box-shadow: var(--shadow-sm);
    }

    .article-list {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .article-list li a {
      font-size: 0.95rem;
      color: var(--text-main);
      display: flex;
      align-items: center;
      gap: 10px;
    }

    .article-list li a:hover {
      color: var(--primary);
      padding-left: 6px;
    }

    /* Image Gallery Cards */
    .media-card {
      background: #ffffff;
      border-radius: var(--radius);
      border: 1px solid var(--border-light);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }

    .media-card img {
      width: 100%;
      height: 220px;
      object-fit: cover;
    }

    .media-body {
      padding: 20px;
    }

    /* Footer */
    .footer {
      background: #191c20;
      color: #abb3bf;
      padding: 60px 0 30px;
      border-top: 4px solid var(--primary);
      font-size: 0.92rem;
    }

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

    .footer-brand h4 {
      color: #ffffff;
      font-size: 1.3rem;
      margin-bottom: 14px;
    }

    .footer-brand p {
      line-height: 1.7;
      margin-bottom: 16px;
      color: #8f98a5;
    }

    .footer-col h5 {
      color: #ffffff;
      font-size: 1rem;
      margin-bottom: 16px;
      position: relative;
      padding-bottom: 8px;
    }

    .footer-col h5::after {
      content: "";
      position: absolute;
      left: 0;
      bottom: 0;
      width: 24px;
      height: 2px;
      background: var(--primary);
    }

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

    .footer-links a {
      color: #abb3bf;
    }

    .footer-links a:hover {
      color: #ffffff;
      padding-left: 4px;
    }

    .friend-links {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      margin-top: 10px;
    }

    .friend-links a {
      background: #252a30;
      color: #abb3bf;
      padding: 4px 10px;
      border-radius: 4px;
      font-size: 0.85rem;
    }

    .friend-links a:hover {
      background: var(--primary);
      color: #ffffff;
    }

    .footer-bottom {
      border-top: 1px solid #2d333b;
      padding-top: 24px;
      text-align: center;
      color: #6e7681;
      font-size: 0.88rem;
    }

    /* Float Bar */
    .float-contact {
      position: fixed;
      right: 20px;
      bottom: 30px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .float-btn {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: var(--primary);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 4px 16px rgba(211, 47, 47, 0.4);
      cursor: pointer;
      border: none;
      font-size: 1.2rem;
      transition: var(--transition);
    }

    .float-btn:hover {
      transform: scale(1.1);
      background: var(--primary-dark);
    }

    /* Responsive */
    @media (max-width: 992px) {
      .hero-title {
        font-size: 2.2rem;
      }
      .grid-4, .process-steps {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-3 {
        grid-template-columns: repeat(2, 1fr);
      }
      .hero-metrics {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #ffffff;
        flex-direction: column;
        padding: 20px;
        box-shadow: var(--shadow-md);
        border-bottom: 1px solid var(--border-light);
      }
      .nav-links.active {
        display: flex;
      }
      .menu-toggle {
        display: block;
      }
      .contact-grid {
        grid-template-columns: 1fr;
      }
    }

    @media (max-width: 640px) {
      .hero-title {
        font-size: 1.8rem;
      }
      .grid-2, .grid-3, .grid-4, .process-steps, .hero-metrics, .footer-grid {
        grid-template-columns: 1fr;
      }
      .rating-banner {
        flex-direction: column;
        text-align: center;
        gap: 20px;
      }
      .form-grid {
        grid-template-columns: 1fr;
      }
      .form-group.full-width {
        grid-column: span 1;
      }
      .form-wrapper {
        padding: 24px 16px;
      }
    }