:root {
      --primary: #4f46e5;
      --primary-hover: #4338ca;
      --accent: #ec4899;
      --accent-glow: #f43f5e;
      --secondary: #06b6d4;
      --bg-base: #f8fafc;
      --bg-surface: #ffffff;
      --bg-soft: #f1f5f9;
      --text-main: #0f172a;
      --text-muted: #475569;
      --text-light: #64748b;
      --border-color: #e2e8f0;
      --border-light: #f1f5f9;
      --card-shadow: 0 10px 25px -5px rgba(15, 23, 42, 0.04), 0 8px 10px -6px rgba(15, 23, 42, 0.04);
      --card-shadow-hover: 0 20px 30px -10px rgba(79, 70, 229, 0.12), 0 10px 15px -5px rgba(15, 23, 42, 0.04);
      --radius-sm: 8px;
      --radius-md: 14px;
      --radius-lg: 20px;
      --radius-full: 9999px;
      --max-width: 1200px;
    }

    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      -webkit-tap-highlight-color: transparent;
    }

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

    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
      background-color: var(--bg-base);
      color: var(--text-main);
      line-height: 1.6;
      overflow-x: hidden;
      display: flex;
      flex-direction: column;
      min-height: 100vh;
      background-image: 
        radial-gradient(at 0% 0%, rgba(79, 70, 229, 0.05) 0px, transparent 50%),
        radial-gradient(at 100% 100%, rgba(236, 72, 153, 0.05) 0px, transparent 50%),
        radial-gradient(at 50% 50%, rgba(6, 182, 212, 0.03) 0px, transparent 50%);
      background-attachment: fixed;
    }

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

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

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

    /* 顶部导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(255, 255, 255, 0.88);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border-bottom: 1px solid rgba(226, 232, 240, 0.8);
      transition: all 0.3s ease;
    }

    .header-inner {
      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;
    }

    .brand-text {
      font-size: 1.25rem;
      font-weight: 800;
      letter-spacing: -0.5px;
      background: linear-gradient(135deg, var(--primary), var(--accent));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

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

    .nav-links li a {
      padding: 8px 14px;
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--text-muted);
      border-radius: var(--radius-sm);
      display: inline-block;
    }

    .nav-links li a:hover,
    .nav-links li a.active {
      color: var(--primary);
      background: rgba(79, 70, 229, 0.06);
    }

    .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: var(--radius-full);
      border: 1px solid transparent;
      cursor: pointer;
      transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
      white-space: nowrap;
    }

    .btn-primary {
      background: linear-gradient(135deg, var(--primary), #6366f1);
      color: #ffffff;
      box-shadow: 0 4px 14px rgba(79, 70, 229, 0.3);
    }

    .btn-primary:hover {
      background: linear-gradient(135deg, var(--primary-hover), var(--primary));
      box-shadow: 0 6px 20px rgba(79, 70, 229, 0.4);
      transform: translateY(-1px);
    }

    .btn-accent {
      background: linear-gradient(135deg, var(--accent), var(--accent-glow));
      color: #ffffff;
      box-shadow: 0 4px 14px rgba(236, 72, 153, 0.3);
    }

    .btn-accent:hover {
      opacity: 0.95;
      transform: translateY(-1px);
      box-shadow: 0 6px 20px rgba(236, 72, 153, 0.4);
    }

    .btn-outline {
      border-color: var(--border-color);
      background: var(--bg-surface);
      color: var(--text-main);
    }

    .btn-outline:hover {
      border-color: var(--primary);
      color: var(--primary);
      background: rgba(79, 70, 229, 0.04);
    }

    .menu-toggle {
      display: none;
      background: none;
      border: none;
      padding: 8px;
      cursor: pointer;
      color: var(--text-main);
    }

    /* 首屏 Hero (无图设计) */
    .hero-section {
      padding: 80px 0 60px;
      position: relative;
      overflow: hidden;
    }

    .hero-content {
      text-align: center;
      max-width: 880px;
      margin: 0 auto;
      position: relative;
      z-index: 2;
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      padding: 6px 16px;
      border-radius: var(--radius-full);
      background: linear-gradient(90deg, rgba(79, 70, 229, 0.1), rgba(236, 72, 153, 0.1));
      border: 1px solid rgba(79, 70, 229, 0.2);
      color: var(--primary);
      font-size: 0.875rem;
      font-weight: 600;
      margin-bottom: 24px;
    }

    .hero-title {
      font-size: 2.75rem;
      font-weight: 900;
      line-height: 1.25;
      letter-spacing: -1px;
      margin-bottom: 20px;
      color: var(--text-main);
    }

    .hero-title-highlight {
      background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 50%, var(--secondary) 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: 36px;
      max-width: 720px;
      margin-left: auto;
      margin-right: auto;
    }

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

    .hero-stats {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      padding: 24px;
      background: var(--bg-surface);
      border-radius: var(--radius-lg);
      border: 1px solid var(--border-color);
      box-shadow: var(--card-shadow);
      margin-top: 20px;
    }

    .stat-item {
      text-align: center;
      position: relative;
    }

    .stat-item:not(:last-child)::after {
      content: "";
      position: absolute;
      right: 0;
      top: 15%;
      height: 70%;
      width: 1px;
      background: var(--border-color);
    }

    .stat-num {
      font-size: 1.85rem;
      font-weight: 800;
      color: var(--text-main);
      display: block;
      margin-bottom: 4px;
      background: linear-gradient(135deg, var(--primary), var(--accent));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .stat-label {
      font-size: 0.85rem;
      color: var(--text-light);
      font-weight: 500;
    }

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

    .section-header {
      text-align: center;
      max-width: 700px;
      margin: 0 auto 50px;
    }

    .section-tag {
      font-size: 0.825rem;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 1.5px;
      color: var(--primary);
      margin-bottom: 10px;
      display: block;
    }

    .section-title {
      font-size: 2.1rem;
      font-weight: 800;
      color: var(--text-main);
      margin-bottom: 16px;
      line-height: 1.3;
    }

    .section-subtitle {
      font-size: 1rem;
      color: var(--text-muted);
    }

    /* 平台矩阵与标签云 */
    .model-pills {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
      margin-bottom: 30px;
    }

    .model-pill {
      background: var(--bg-surface);
      border: 1px solid var(--border-color);
      padding: 8px 18px;
      border-radius: var(--radius-full);
      font-size: 0.9rem;
      font-weight: 600;
      color: var(--text-main);
      box-shadow: 0 2px 6px rgba(0,0,0,0.02);
      transition: all 0.2s ease;
    }

    .model-pill:hover {
      border-color: var(--primary);
      color: var(--primary);
      transform: translateY(-2px);
      box-shadow: 0 6px 12px rgba(79, 70, 229, 0.08);
    }

    /* 卡片网格 */
    .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;
      align-items: center;
    }

    .feature-card {
      background: var(--bg-surface);
      border-radius: var(--radius-md);
      padding: 30px 24px;
      border: 1px solid var(--border-color);
      box-shadow: var(--card-shadow);
      transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
      display: flex;
      flex-direction: column;
      height: 100%;
    }

    .feature-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--card-shadow-hover);
      border-color: rgba(79, 70, 229, 0.3);
    }

    .card-icon {
      width: 50px;
      height: 50px;
      border-radius: 12px;
      background: linear-gradient(135deg, rgba(79, 70, 229, 0.1), rgba(236, 72, 153, 0.1));
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--primary);
      font-size: 1.5rem;
    }

    .card-title {
      font-size: 1.25rem;
      font-weight: 700;
      margin-bottom: 12px;
      color: var(--text-main);
    }

    .card-text {
      font-size: 0.925rem;
      color: var(--text-muted);
      line-height: 1.65;
      flex-grow: 1;
    }

    /* 案例展示 */
    .media-card {
      background: var(--bg-surface);
      border-radius: var(--radius-md);
      overflow: hidden;
      border: 1px solid var(--border-color);
      box-shadow: var(--card-shadow);
      transition: all 0.3s ease;
    }

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

    .media-img-wrap {
      width: 100%;
      background: var(--bg-soft);
      overflow: hidden;
    }

    .media-img-wrap img {
      width: 100%;
      height: 220px;
      object-fit: cover;
      transition: transform 0.4s ease;
    }

    .media-card:hover .media-img-wrap img {
      transform: scale(1.04);
    }

    .media-body {
      padding: 20px;
    }

    .media-tag {
      font-size: 0.75rem;
      font-weight: 700;
      color: var(--accent);
      text-transform: uppercase;
      margin-bottom: 6px;
      display: inline-block;
    }

    .media-title {
      font-size: 1.1rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 8px;
    }

    /* 对比评测表格与评分卡 */
    .eval-container {
      display: grid;
      grid-template-columns: 320px 1fr;
      gap: 30px;
      align-items: start;
    }

    .score-card {
      background: linear-gradient(145deg, #1e1b4b, #312e81);
      color: #ffffff;
      border-radius: var(--radius-lg);
      padding: 36px 28px;
      text-align: center;
      box-shadow: 0 15px 30px rgba(49, 46, 129, 0.25);
    }

    .score-badge {
      display: inline-block;
      padding: 4px 12px;
      background: rgba(236, 72, 153, 0.3);
      border-radius: var(--radius-full);
      font-size: 0.8rem;
      font-weight: 600;
      color: #fbcfe8;
      margin-bottom: 16px;
    }

    .score-stars {
      color: #facc15;
      font-size: 1.3rem;
      margin-bottom: 12px;
      letter-spacing: 4px;
    }

    .score-value {
      font-size: 3.5rem;
      font-weight: 900;
      line-height: 1;
      margin-bottom: 8px;
      color: #ffffff;
    }

    .score-value small {
      font-size: 1.25rem;
      color: #c7d2fe;
      font-weight: 600;
    }

    .score-desc {
      font-size: 0.9rem;
      color: #e0e7ff;
      margin-bottom: 24px;
      line-height: 1.6;
    }

    .table-card {
      background: var(--bg-surface);
      border-radius: var(--radius-lg);
      border: 1px solid var(--border-color);
      box-shadow: var(--card-shadow);
      overflow-x: auto;
    }

    .eval-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      font-size: 0.925rem;
      min-width: 500px;
    }

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

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

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

    .eval-table td:nth-child(2) {
      color: var(--primary);
      font-weight: 600;
      background: rgba(79, 70, 229, 0.02);
    }

    /* 流程时间线 */
    .timeline {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      position: relative;
    }

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

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

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

    /* 用户评论 */
    .comment-card {
      background: var(--bg-surface);
      border-radius: var(--radius-md);
      padding: 26px;
      border: 1px solid var(--border-color);
      box-shadow: var(--card-shadow);
      display: flex;
      flex-direction: column;
      height: 100%;
    }

    .comment-header {
      display: flex;
      align-items: center;
      gap: 14px;
      margin-bottom: 16px;
    }

    .avatar-placeholder {
      width: 46px;
      height: 46px;
      border-radius: 50%;
      background: linear-gradient(135deg, var(--primary), var(--accent));
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 1.1rem;
      flex-shrink: 0;
    }

    .comment-meta h4 {
      font-size: 1rem;
      font-weight: 700;
      color: var(--text-main);
    }

    .comment-meta span {
      font-size: 0.8rem;
      color: var(--text-light);
    }

    .comment-body {
      font-size: 0.9rem;
      color: var(--text-muted);
      line-height: 1.6;
      flex-grow: 1;
    }

    /* FAQ 手风琴 */
    .faq-wrapper {
      max-width: 860px;
      margin: 0 auto;
    }

    .faq-item {
      background: var(--bg-surface);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      margin-bottom: 14px;
      overflow: hidden;
      box-shadow: 0 2px 6px rgba(0,0,0,0.02);
      transition: border-color 0.2s ease;
    }

    .faq-item:hover {
      border-color: rgba(79, 70, 229, 0.4);
    }

    .faq-question {
      padding: 20px 24px;
      font-size: 1.05rem;
      font-weight: 700;
      color: var(--text-main);
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: space-between;
      user-select: none;
    }

    .faq-question::after {
      content: "+";
      font-size: 1.4rem;
      font-weight: 400;
      color: var(--primary);
      transition: transform 0.2s ease;
    }

    .faq-item.active .faq-question::after {
      content: "-";
      transform: rotate(180deg);
    }

    .faq-answer {
      padding: 0 24px 20px;
      font-size: 0.925rem;
      color: var(--text-muted);
      line-height: 1.65;
      display: none;
      border-top: 1px solid var(--border-light);
      padding-top: 14px;
    }

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

    /* 表单与需求匹配 */
    .form-container {
      background: var(--bg-surface);
      border-radius: var(--radius-lg);
      padding: 40px;
      border: 1px solid var(--border-color);
      box-shadow: var(--card-shadow);
      max-width: 760px;
      margin: 0 auto;
    }

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

    .form-group 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-radius: var(--radius-sm);
      border: 1px solid var(--border-color);
      font-size: 0.95rem;
      background: var(--bg-base);
      color: var(--text-main);
      transition: all 0.2s ease;
      font-family: inherit;
    }

    .form-control:focus {
      outline: none;
      border-color: var(--primary);
      background: #ffffff;
      box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
    }

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

    /* 文章列表 & 友情链接 */
    .article-links-wrap {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      margin-top: 20px;
    }

    .article-chip {
      background: var(--bg-surface);
      border: 1px solid var(--border-color);
      padding: 10px 18px;
      border-radius: var(--radius-sm);
      font-size: 0.9rem;
      color: var(--text-muted);
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }

    .article-chip:hover {
      border-color: var(--primary);
      color: var(--primary);
    }

    .friend-links {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
      margin-top: 14px;
    }

    .friend-links a {
      color: var(--text-light);
      font-size: 0.875rem;
    }

    .friend-links a:hover {
      color: var(--primary);
      text-decoration: underline;
    }

    /* 页脚 */
    .site-footer {
      background: #0f172a;
      color: #94a3b8;
      padding: 70px 0 30px;
      border-top: 1px solid #1e293b;
      margin-top: auto;
    }

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

    .footer-col h4 {
      color: #ffffff;
      font-size: 1.05rem;
      font-weight: 700;
      margin-bottom: 20px;
    }

    .footer-col ul {
      list-style: none;
    }

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

    .footer-col ul li a {
      color: #94a3b8;
      font-size: 0.9rem;
    }

    .footer-col ul li a:hover {
      color: #ffffff;
    }

    .qr-card {
      display: inline-flex;
      flex-direction: column;
      align-items: center;
      background: #1e293b;
      padding: 12px;
      border-radius: var(--radius-sm);
      border: 1px solid #334155;
    }

    .qr-card img {
      width: 110px;
      height: 110px;
      border-radius: 4px;
      object-fit: cover;
    }

    .qr-card span {
      font-size: 0.75rem;
      color: #cbd5e1;
      margin-top: 8px;
    }

    .footer-bottom {
      border-top: 1px solid #1e293b;
      padding-top: 24px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 0.85rem;
      flex-wrap: wrap;
      gap: 12px;
    }

    /* 浮动组件 */
    .float-panel {
      position: fixed;
      right: 24px;
      bottom: 30px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .float-btn {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: var(--bg-surface);
      color: var(--text-main);
      box-shadow: 0 4px 16px rgba(0,0,0,0.12);
      display: flex;
      align-items: center;
      justify-content: center;
      border: 1px solid var(--border-color);
      cursor: pointer;
      transition: all 0.2s ease;
      position: relative;
    }

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

    .float-qr-pop {
      position: absolute;
      right: 60px;
      bottom: 0;
      background: #ffffff;
      padding: 12px;
      border-radius: var(--radius-sm);
      box-shadow: 0 10px 25px rgba(0,0,0,0.15);
      border: 1px solid var(--border-color);
      display: none;
      width: 140px;
      text-align: center;
    }

    .float-btn:hover .float-qr-pop {
      display: block;
    }

    .float-qr-pop img {
      width: 100%;
      height: auto;
    }

    .float-qr-pop span {
      display: block;
      font-size: 0.75rem;
      color: var(--text-muted);
      margin-top: 6px;
    }

    /* 响应式调整 */
    @media (max-width: 1024px) {
      .grid-4 {
        grid-template-columns: repeat(2, 1fr);
      }
      .timeline {
        grid-template-columns: repeat(2, 1fr);
      }
      .eval-container {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #ffffff;
        flex-direction: column;
        padding: 20px;
        border-bottom: 1px solid var(--border-color);
        box-shadow: 0 10px 20px rgba(0,0,0,0.05);
      }
      .nav-links.active {
        display: flex;
      }
      .menu-toggle {
        display: block;
      }
      .hero-title {
        font-size: 2rem;
      }
      .hero-stats {
        grid-template-columns: repeat(2, 1fr);
      }
      .stat-item:nth-child(2)::after {
        display: none;
      }
      .grid-3 {
        grid-template-columns: 1fr;
      }
      .grid-2 {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .form-container {
        padding: 24px;
      }
    }