:root {
      --primary-color: #4f46e5;
      --primary-gradient: linear-gradient(135deg, #6366f1 0%, #a855f7 50%, #ec4899 100%);
      --primary-hover: #4338ca;
      --secondary-color: #06b6d4;
      --accent-color: #f59e0b;
      --bg-main: #f8fafc;
      --bg-card: #ffffff;
      --bg-subtle: #f1f5f9;
      --text-main: #0f172a;
      --text-muted: #475569;
      --border-color: #e2e8f0;
      --shadow-sm: 0 2px 4px rgba(0,0,0,0.05);
      --shadow-md: 0 10px 25px -5px rgba(99, 102, 241, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.05);
      --shadow-lg: 0 20px 30px -10px rgba(79, 70, 229, 0.15);
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 20px;
      --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(--bg-main);
      color: var(--text-main);
      line-height: 1.6;
    }

    body {
      overflow-x: hidden;
    }

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

    /* Header & Navigation */
    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);
    }

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

    .brand-logo {
      display: flex;
      align-items: center;
      gap: 12px;
      text-decoration: none;
      color: var(--text-main);
      font-weight: 700;
      font-size: 1.25rem;
    }

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

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

    .nav-links li a {
      text-decoration: none;
      color: var(--text-muted);
      font-size: 0.95rem;
      font-weight: 500;
      padding: 8px 14px;
      border-radius: var(--radius-sm);
      transition: all 0.2s ease;
      display: inline-block;
    }

    .nav-links li a:hover,
    .nav-links li a.active {
      color: var(--primary-color);
      background-color: rgba(99, 102, 241, 0.08);
    }

    .nav-cta {
      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: 99px;
      text-decoration: none;
      transition: all 0.3s ease;
      cursor: pointer;
      border: none;
      outline: none;
    }

    .btn-primary {
      background: var(--primary-gradient);
      color: #ffffff;
      box-shadow: 0 4px 14px rgba(99, 102, 241, 0.35);
    }

    .btn-primary:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 20px rgba(99, 102, 241, 0.45);
    }

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

    .btn-secondary:hover {
      border-color: var(--primary-color);
      color: var(--primary-color);
      background-color: #fafafa;
    }

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

    /* Section Styling */
    section {
      padding: 80px 0;
      position: relative;
    }

    .section-title-wrap {
      text-align: center;
      max-width: 760px;
      margin: 0 auto 50px auto;
    }

    .section-badge {
      display: inline-block;
      padding: 4px 14px;
      background: rgba(99, 102, 241, 0.1);
      color: var(--primary-color);
      font-size: 0.85rem;
      font-weight: 700;
      border-radius: 50px;
      margin-bottom: 12px;
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }

    .section-title {
      font-size: 2.25rem;
      font-weight: 800;
      color: var(--text-main);
      margin-bottom: 16px;
      line-height: 1.3;
    }

    .section-desc {
      font-size: 1.05rem;
      color: var(--text-muted);
    }

    /* 首屏 Hero Section (严禁图片) */
    .hero-section {
      padding: 100px 0 80px 0;
      background: radial-gradient(circle at 50% 0%, rgba(168, 85, 247, 0.12) 0%, rgba(99, 102, 241, 0.05) 50%, rgba(248, 250, 252, 0) 100%);
      text-align: center;
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      background: #ffffff;
      border: 1px solid rgba(99, 102, 241, 0.2);
      padding: 6px 18px;
      border-radius: 50px;
      font-size: 0.9rem;
      color: var(--primary-color);
      font-weight: 600;
      margin-bottom: 24px;
      box-shadow: var(--shadow-sm);
    }

    .hero-title {
      font-size: 3rem;
      font-weight: 900;
      line-height: 1.25;
      margin-bottom: 20px;
      background: linear-gradient(135deg, #1e1b4b 0%, #4338ca 50%, #6b21a8 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .hero-subtitle {
      font-size: 1.2rem;
      color: var(--text-muted);
      max-width: 800px;
      margin: 0 auto 36px auto;
    }

    .hero-actions {
      display: flex;
      justify-content: center;
      gap: 16px;
      flex-wrap: wrap;
      margin-bottom: 60px;
    }

    .hero-actions .btn {
      padding: 14px 36px;
      font-size: 1.05rem;
    }

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

    .hero-feature-card {
      background: var(--bg-card);
      padding: 24px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
      transition: all 0.3s ease;
    }

    .hero-feature-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
      border-color: rgba(99, 102, 241, 0.3);
    }

    .hero-feature-icon {
      width: 48px;
      height: 48px;
      background: var(--primary-gradient);
      border-radius: var(--radius-sm);
      display: flex;
      align-items: center;
      justify-content: center;
      color: #fff;
      font-size: 1.25rem;
      font-weight: bold;
      margin-bottom: 16px;
    }

    .hero-feature-title {
      font-size: 1.1rem;
      font-weight: 700;
      margin-bottom: 8px;
    }

    .hero-feature-desc {
      font-size: 0.9rem;
      color: var(--text-muted);
    }

    /* 关于我们与平台介绍 */
    .about-card {
      background: var(--bg-card);
      border-radius: var(--radius-lg);
      padding: 40px;
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-md);
    }

    .about-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
    }

    .about-highlights {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 20px;
      margin-top: 24px;
    }

    .highlight-item {
      background: var(--bg-subtle);
      padding: 16px;
      border-radius: var(--radius-sm);
      border-left: 4px solid var(--primary-color);
    }

    .highlight-item h4 {
      font-size: 1rem;
      color: var(--text-main);
      margin-bottom: 4px;
    }

    .highlight-item p {
      font-size: 0.85rem;
      color: var(--text-muted);
    }

    /* Cards & Grids */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .service-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 28px;
      transition: all 0.3s ease;
      display: flex;
      flex-direction: column;
    }

    .service-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-lg);
      border-color: rgba(99, 102, 241, 0.4);
    }

    .service-tag {
      align-self: flex-start;
      font-size: 0.75rem;
      font-weight: 700;
      color: var(--primary-color);
      background: rgba(99, 102, 241, 0.1);
      padding: 2px 10px;
      border-radius: 12px;
      margin-bottom: 14px;
    }

    .service-title {
      font-size: 1.2rem;
      font-weight: 700;
      margin-bottom: 10px;
    }

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

    /* Model Badges */
    .models-wrapper {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 30px;
      margin-top: 40px;
    }

    .models-title {
      font-size: 1.1rem;
      font-weight: 700;
      margin-bottom: 20px;
      text-align: center;
    }

    .models-tags {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
    }

    .model-badge {
      background: var(--bg-subtle);
      border: 1px solid var(--border-color);
      color: var(--text-main);
      padding: 6px 14px;
      border-radius: 20px;
      font-size: 0.88rem;
      font-weight: 600;
      transition: all 0.2s;
    }

    .model-badge:hover {
      background: var(--primary-gradient);
      color: #fff;
      border-color: transparent;
    }

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

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

    .process-num {
      font-size: 2.5rem;
      font-weight: 900;
      color: rgba(99, 102, 241, 0.15);
      position: absolute;
      top: 15px;
      right: 20px;
    }

    .process-title {
      font-size: 1.1rem;
      font-weight: 700;
      margin-bottom: 8px;
    }

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

    /* 案例展示区 */
    .case-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

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

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

    .case-img-wrap {
      width: 100%;
      height: 200px;
      overflow: hidden;
      background: var(--bg-subtle);
    }

    .ai-page-image {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
    }

    .case-content {
      padding: 20px;
    }

    .case-title {
      font-size: 1.1rem;
      font-weight: 700;
      margin-bottom: 8px;
    }

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

    /* 对比评测 */
    .comparison-card {
      background: var(--bg-card);
      border-radius: var(--radius-lg);
      padding: 36px;
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-md);
    }

    .rating-banner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: linear-gradient(135deg, rgba(99, 102, 241, 0.08) 0%, rgba(236, 72, 153, 0.08) 100%);
      padding: 24px 32px;
      border-radius: var(--radius-md);
      margin-bottom: 30px;
      border: 1px solid rgba(99, 102, 241, 0.2);
    }

    .rating-score {
      display: flex;
      align-items: baseline;
      gap: 10px;
    }

    .score-num {
      font-size: 3rem;
      font-weight: 900;
      color: var(--primary-color);
    }

    .score-max {
      font-size: 1.2rem;
      color: var(--text-muted);
    }

    .rating-stars {
      color: #f59e0b;
      font-size: 1.5rem;
      letter-spacing: 2px;
    }

    .table-responsive {
      overflow-x: auto;
    }

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

    .comp-table th, .comp-table td {
      padding: 16px 20px;
      border-bottom: 1px solid var(--border-color);
    }

    .comp-table th {
      background: var(--bg-subtle);
      font-weight: 700;
      color: var(--text-main);
    }

    .comp-table td.highlight {
      font-weight: 700;
      color: var(--primary-color);
      background: rgba(99, 102, 241, 0.03);
    }

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

    .price-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 30px;
      text-align: center;
      position: relative;
    }

    .price-card.popular {
      border: 2px solid var(--primary-color);
      box-shadow: var(--shadow-md);
    }

    .popular-badge {
      position: absolute;
      top: -12px;
      left: 50%;
      transform: translateX(-50%);
      background: var(--primary-gradient);
      color: #fff;
      padding: 2px 14px;
      border-radius: 12px;
      font-size: 0.75rem;
      font-weight: 700;
    }

    .price-val {
      font-size: 2.25rem;
      font-weight: 800;
      color: var(--text-main);
      margin: 16px 0;
    }

    .price-val span {
      font-size: 0.9rem;
      color: var(--text-muted);
      font-weight: normal;
    }

    .price-list {
      list-style: none;
      text-align: left;
      margin: 20px 0;
      font-size: 0.9rem;
      color: var(--text-muted);
    }

    .price-list li {
      padding: 6px 0;
      border-bottom: 1px dashed var(--border-color);
    }

    /* FAQ 折叠面板 */
    .faq-container {
      max-width: 900px;
      margin: 0 auto;
    }

    .faq-item {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-sm);
      margin-bottom: 12px;
      overflow: hidden;
    }

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

    .faq-question::after {
      content: '+';
      font-size: 1.4rem;
      color: var(--primary-color);
      transition: transform 0.3s;
    }

    .faq-item.active .faq-question::after {
      content: '−';
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      background: var(--bg-subtle);
      color: var(--text-muted);
      font-size: 0.95rem;
    }

    .faq-item.active .faq-answer {
      max-height: 300px;
      padding: 20px 24px;
      border-top: 1px solid var(--border-color);
    }

    /* 客户评论 */
    .reviews-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

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

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

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

    .user-info h5 {
      font-size: 1rem;
      color: var(--text-main);
    }

    .user-info span {
      font-size: 0.8rem;
      color: var(--text-muted);
    }

    .review-text {
      font-size: 0.92rem;
      color: var(--text-muted);
      font-style: italic;
    }

    /* 文章与百科 */
    .articles-grid {
      display: grid;
      grid-template-columns: 2fr 1fr;
      gap: 30px;
    }

    .article-list {
      list-style: none;
    }

    .article-item {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      padding: 16px 20px;
      border-radius: var(--radius-sm);
      margin-bottom: 12px;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .article-item a {
      text-decoration: none;
      color: var(--text-main);
      font-weight: 600;
      transition: color 0.2s;
    }

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

    .wiki-box {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 24px;
    }

    .wiki-title {
      font-size: 1.1rem;
      font-weight: 700;
      margin-bottom: 14px;
      border-bottom: 2px solid var(--primary-color);
      padding-bottom: 8px;
    }

    /* 联系我们与表单 */
    .contact-card {
      background: var(--bg-card);
      border-radius: var(--radius-lg);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-lg);
      overflow: hidden;
    }

    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
    }

    .contact-info {
      padding: 40px;
      background: linear-gradient(135deg, #1e1b4b 0%, #312e81 100%);
      color: #ffffff;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

    .contact-info h3 {
      font-size: 1.8rem;
      margin-bottom: 16px;
      color: #ffffff;
    }

    .contact-info p {
      color: #cbd5e1;
      font-size: 0.95rem;
      margin-bottom: 24px;
    }

    .contact-detail-list {
      list-style: none;
      margin-bottom: 30px;
    }

    .contact-detail-list li {
      margin-bottom: 14px;
      font-size: 0.95rem;
      color: #e2e8f0;
    }

    .qr-container {
      background: #ffffff;
      padding: 16px;
      border-radius: var(--radius-sm);
      display: inline-block;
      text-align: center;
      width: 140px;
    }

    .qr-container img {
      width: 100%;
      height: auto;
      display: block;
    }

    .qr-container p {
      color: var(--text-main);
      font-size: 0.8rem;
      margin-top: 6px;
      margin-bottom: 0;
      font-weight: 600;
    }

    .form-wrap {
      padding: 40px;
    }

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

    .form-group label {
      display: block;
      font-size: 0.9rem;
      font-weight: 600;
      margin-bottom: 6px;
      color: var(--text-main);
    }

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

    .form-control:focus {
      border-color: var(--primary-color);
      background: #fff;
    }

    textarea.form-control {
      resize: vertical;
      min-height: 100px;
    }

    /* 页脚 Footer */
    footer {
      background: #0f172a;
      color: #94a3b8;
      padding: 60px 0 30px 0;
      border-top: 1px solid #1e293b;
    }

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

    .footer-brand h4 {
      color: #ffffff;
      font-size: 1.25rem;
      margin-bottom: 14px;
    }

    .footer-brand p {
      font-size: 0.9rem;
      line-height: 1.6;
    }

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

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

    .footer-links li {
      margin-bottom: 10px;
    }

    .footer-links a {
      color: #94a3b8;
      text-decoration: none;
      font-size: 0.9rem;
      transition: color 0.2s;
    }

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

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

    .friend-links a {
      color: #94a3b8;
      text-decoration: none;
      font-size: 0.85rem;
      background: #1e293b;
      padding: 4px 10px;
      border-radius: 4px;
      transition: all 0.2s;
    }

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

    .footer-bottom {
      border-top: 1px solid #1e293b;
      padding-top: 24px;
      text-align: center;
      font-size: 0.85rem;
      color: #64748b;
    }

    /* 浮动客服 */
    .floating-kefu {
      position: fixed;
      right: 20px;
      bottom: 30px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .kefu-btn {
      width: 50px;
      height: 50px;
      border-radius: 50%;
      background: var(--primary-gradient);
      color: #fff;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: var(--shadow-lg);
      text-decoration: none;
      font-size: 0.8rem;
      font-weight: bold;
      transition: transform 0.3s;
    }

    .kefu-btn:hover {
      transform: scale(1.1);
    }

    /* 响应式调整 */
    @media (max-width: 1024px) {
      .hero-features-grid, .services-grid, .case-grid, .reviews-grid, .price-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .process-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      .articles-grid {
        grid-template-columns: 1fr;
      }
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: #ffffff;
        flex-direction: column;
        padding: 20px;
        border-bottom: 1px solid var(--border-color);
        box-shadow: var(--shadow-md);
      }
      .nav-links.show {
        display: flex;
      }
      .mobile-toggle {
        display: block;
      }
      .hero-title {
        font-size: 2rem;
      }
      .hero-features-grid, .services-grid, .case-grid, .reviews-grid, .price-grid, .about-grid, .contact-grid {
        grid-template-columns: 1fr;
      }
      .process-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .about-card, .contact-info, .form-wrap {
        padding: 24px;
      }
      .rating-banner {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
      }
    }