:root {
      --primary-purple: #6a11cb;
      --deep-purple: #2575fc;
      --vibrant-purple: #8e2de2;
      --light-purple-bg: #f8f9fe;
      --card-bg: #ffffff;
      --text-main: #1f2438;
      --text-muted: #5e6479;
      --border-color: #e6e8f2;
      --accent-glow: rgba(110, 43, 238, 0.08);
      --purple-gradient: linear-gradient(135deg, #7928ca 0%, #ff0080 100%);
      --soft-gradient: linear-gradient(135deg, #fbfbfe 0%, #f4f0ff 100%);
      --btn-gradient: linear-gradient(135deg, #6a11cb 0%, #8e2de2 100%);
      --container-width: 1200px;
    }

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

    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      background-color: var(--light-purple-bg);
      color: var(--text-main);
      line-height: 1.6;
      overflow-x: hidden;
      font-size: 15px;
    }

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

    /* 顶部导航 */
    .site-header {
      position: sticky;
      top: 0;
      background: rgba(255, 255, 255, 0.96);
      backdrop-filter: blur(10px);
      border-bottom: 1px solid var(--border-color);
      z-index: 1000;
      transition: all 0.3s ease;
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 70px;
    }
    .logo-container {
      display: flex;
      align-items: center;
      gap: 12px;
      text-decoration: none;
    }
    .ai-page-logo {
      height: 38px;
      width: auto;
      display: block;
    }
    .brand-title {
      font-size: 18px;
      font-weight: 700;
      color: var(--text-main);
      letter-spacing: 0.5px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      list-style: none;
      gap: 0;
    }
    .nav-links a {
      text-decoration: none;
      color: var(--text-main);
      font-weight: 500;
      padding: 8px 14px;
      border-radius: 6px;
      transition: color 0.2s ease, background 0.2s ease;
      font-size: 14px;
      display: inline-block;
    }
    .nav-links a:hover {
      color: var(--primary-purple);
      background: rgba(142, 45, 226, 0.05);
    }
    .header-actions {
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 9px 20px;
      font-size: 14px;
      font-weight: 600;
      border-radius: 8px;
      text-decoration: none;
      cursor: pointer;
      transition: all 0.25s ease;
      border: 1px solid transparent;
      white-space: nowrap;
    }
    .btn-primary {
      background: var(--btn-gradient);
      color: #ffffff;
      box-shadow: 0 4px 14px rgba(110, 43, 238, 0.25);
    }
    .btn-primary:hover {
      opacity: 0.95;
      transform: translateY(-1px);
      box-shadow: 0 6px 18px rgba(110, 43, 238, 0.35);
    }
    .btn-outline {
      border-color: var(--primary-purple);
      color: var(--primary-purple);
      background: #ffffff;
    }
    .btn-outline:hover {
      background: rgba(110, 43, 238, 0.05);
    }
    .mobile-menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 24px;
      color: var(--text-main);
      cursor: pointer;
    }

    /* 首屏 Hero (无图片) */
    .hero-section {
      background: var(--soft-gradient);
      padding: 70px 0 60px;
      border-bottom: 1px solid var(--border-color);
      position: relative;
    }
    .hero-content {
      text-align: center;
      max-width: 860px;
      margin: 0 auto;
    }
    .badge-pill {
      display: inline-block;
      padding: 6px 16px;
      background: #efe9ff;
      color: var(--primary-purple);
      border-radius: 30px;
      font-size: 13px;
      font-weight: 600;
      margin-bottom: 20px;
      border: 1px solid #d9c8fe;
    }
    .hero-title {
      font-size: 38px;
      line-height: 1.3;
      font-weight: 800;
      color: #1a1638;
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }
    .hero-subtitle {
      font-size: 17px;
      color: var(--text-muted);
      line-height: 1.7;
      margin-bottom: 34px;
    }
    .hero-cta-group {
      display: flex;
      justify-content: center;
      gap: 16px;
      flex-wrap: wrap;
      margin-bottom: 40px;
    }
    .btn-large {
      padding: 13px 32px;
      font-size: 16px;
    }
    .hero-data-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 16px;
      margin-top: 20px;
    }
    .data-item {
      background: #ffffff;
      padding: 18px 12px;
      border-radius: 12px;
      border: 1px solid var(--border-color);
      box-shadow: 0 4px 12px var(--accent-glow);
    }
    .data-number {
      font-size: 26px;
      font-weight: 800;
      color: var(--primary-purple);
      margin-bottom: 4px;
    }
    .data-label {
      font-size: 13px;
      color: var(--text-muted);
    }

    /* 通用板块与排版 */
    .section {
      padding: 70px 0;
      position: relative;
    }
    .section-alt {
      background: #ffffff;
    }
    .section-header {
      text-align: center;
      max-width: 700px;
      margin: 0 auto 44px;
    }
    .section-tag {
      font-size: 13px;
      font-weight: 700;
      color: var(--primary-purple);
      text-transform: uppercase;
      letter-spacing: 1px;
      margin-bottom: 8px;
      display: block;
    }
    .section-title {
      font-size: 28px;
      font-weight: 700;
      color: #1a1638;
      margin-bottom: 12px;
    }
    .section-desc {
      font-size: 15px;
      color: var(--text-muted);
    }

    /* 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: 28px;
    }

    .feature-card {
      background: var(--card-bg);
      border: 1px solid var(--border-color);
      border-radius: 12px;
      padding: 26px;
      transition: all 0.3s ease;
      display: flex;
      flex-direction: column;
      height: 100%;
    }
    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: 0 10px 24px rgba(110, 43, 238, 0.09);
      border-color: #c9b1ff;
    }
    .feature-icon-box {
      width: 44px;
      height: 44px;
      background: #f1e9ff;
      color: var(--primary-purple);
      border-radius: 10px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 20px;
      margin-bottom: 18px;
      font-weight: 700;
    }
    .feature-title {
      font-size: 18px;
      font-weight: 700;
      margin-bottom: 10px;
      color: #1a1638;
    }
    .feature-text {
      color: var(--text-muted);
      font-size: 14px;
      line-height: 1.6;
      flex-grow: 1;
    }

    /* 平台支持模型标签流 */
    .model-tag-stream {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
      justify-content: center;
      margin-top: 24px;
    }
    .model-pill {
      background: #ffffff;
      border: 1px solid #e0e2ec;
      padding: 5px 12px;
      border-radius: 20px;
      font-size: 12px;
      font-weight: 500;
      color: #3b4256;
      transition: all 0.2s ease;
    }
    .model-pill:hover {
      background: var(--primary-purple);
      color: #ffffff;
      border-color: var(--primary-purple);
    }

    /* 媒体与图文混排 */
    .media-card {
      background: #ffffff;
      border-radius: 12px;
      overflow: hidden;
      border: 1px solid var(--border-color);
      display: flex;
      flex-direction: column;
    }
    .media-card-img-wrap {
      width: 100%;
      aspect-ratio: 16 / 9;
      background: #eceffd;
      overflow: hidden;
    }
    .media-card-img-wrap.square {
      aspect-ratio: 1 / 1;
    }
    .media-card-img-wrap img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
      transition: transform 0.4s ease;
    }
    .media-card:hover .media-card-img-wrap img {
      transform: scale(1.03);
    }
    .media-card-body {
      padding: 20px;
      flex-grow: 1;
    }

    /* 对比评测专属区域 */
    .rating-banner {
      background: #fdf6ff;
      border: 1px solid #e9d5ff;
      border-radius: 12px;
      padding: 24px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 30px;
      flex-wrap: wrap;
      gap: 16px;
    }
    .rating-left {
      display: flex;
      align-items: center;
      gap: 18px;
    }
    .score-badge {
      font-size: 32px;
      font-weight: 900;
      color: #7928ca;
      line-height: 1;
    }
    .stars {
      color: #ff9900;
      font-size: 20px;
      letter-spacing: 2px;
    }
    .comparison-table-wrapper {
      overflow-x: auto;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 12px;
    }
    .comp-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      font-size: 14px;
    }
    .comp-table th, .comp-table td {
      padding: 16px 20px;
      border-bottom: 1px solid var(--border-color);
    }
    .comp-table th {
      background: #fafaff;
      color: #1a1638;
      font-weight: 700;
    }
    .comp-highlight {
      background: #faf6ff;
      font-weight: 600;
      color: var(--primary-purple);
    }

    /* 流程步骤 */
    .step-list {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
    }
    .step-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 12px;
      padding: 24px;
      position: relative;
    }
    .step-number {
      font-size: 24px;
      font-weight: 800;
      color: #d1b9fd;
      margin-bottom: 12px;
    }

    /* FAQ 折叠 */
    .faq-container {
      max-width: 860px;
      margin: 0 auto;
    }
    .faq-item {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 10px;
      margin-bottom: 12px;
      overflow: hidden;
    }
    .faq-question {
      width: 100%;
      text-align: left;
      padding: 18px 22px;
      background: none;
      border: none;
      outline: none;
      font-size: 16px;
      font-weight: 600;
      color: var(--text-main);
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .faq-question:hover {
      color: var(--primary-purple);
    }
    .faq-icon {
      font-size: 18px;
      color: var(--primary-purple);
      transition: transform 0.25s ease;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s cubic-bezier(0, 1, 0, 1);
      padding: 0 22px;
      color: var(--text-muted);
      font-size: 14px;
      line-height: 1.7;
    }
    .faq-item.active .faq-answer {
      max-height: 500px;
      padding-bottom: 20px;
      transition: max-height 0.3s ease-in-out;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }

    /* 客户评论卡片 */
    .testimonial-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 12px;
      padding: 24px;
      display: flex;
      flex-direction: column;
      height: 100%;
    }
    .user-info {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 14px;
    }
    .user-avatar-text {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: #ebe4ff;
      color: var(--primary-purple);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 16px;
    }
    .user-meta h4 {
      font-size: 15px;
      font-weight: 700;
      color: #1a1638;
    }
    .user-meta span {
      font-size: 12px;
      color: var(--text-muted);
    }

    /* 表单与需求匹配 */
    .form-wrapper {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 14px;
      padding: 34px;
      box-shadow: 0 10px 30px rgba(110, 43, 238, 0.05);
      max-width: 680px;
      margin: 0 auto;
    }
    .form-group {
      margin-bottom: 20px;
    }
    .form-label {
      display: block;
      font-size: 14px;
      font-weight: 600;
      margin-bottom: 6px;
      color: #1a1638;
    }
    .form-control {
      width: 100%;
      padding: 12px 16px;
      border: 1px solid var(--border-color);
      border-radius: 8px;
      font-size: 14px;
      outline: none;
      transition: border-color 0.2s ease, box-shadow 0.2s ease;
      background: #fafaff;
      color: var(--text-main);
    }
    .form-control:focus {
      border-color: var(--primary-purple);
      box-shadow: 0 0 0 3px rgba(110, 43, 238, 0.12);
      background: #ffffff;
    }
    textarea.form-control {
      resize: vertical;
      min-height: 100px;
    }

    /* 底部专属布局 */
    .site-footer {
      background: #141324;
      color: #c5c7d5;
      padding: 60px 0 30px;
      font-size: 14px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 36px;
      margin-bottom: 40px;
    }
    .footer-col h4 {
      color: #ffffff;
      font-size: 16px;
      margin-bottom: 18px;
      font-weight: 600;
    }
    .footer-links {
      list-style: none;
    }
    .footer-links li {
      margin-bottom: 10px;
    }
    .footer-links a {
      color: #9ea2ba;
      text-decoration: none;
      transition: color 0.2s;
    }
    .footer-links a:hover {
      color: #ffffff;
    }
    .footer-qr-block {
      display: flex;
      flex-direction: column;
      gap: 10px;
      max-width: 130px;
    }
    .footer-qr-block img {
      width: 100%;
      height: auto;
      border-radius: 6px;
      border: 2px solid #2f2d48;
    }
    .footer-bottom {
      border-top: 1px solid #282640;
      padding-top: 24px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 12px;
      font-size: 13px;
      color: #797c96;
    }
    .friend-links-area {
      margin-top: 20px;
      padding-top: 20px;
      border-top: 1px solid #282640;
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      align-items: center;
      font-size: 13px;
    }
    .friend-links-area a {
      color: #8c90ab;
      text-decoration: none;
    }
    .friend-links-area a:hover {
      color: #ffffff;
    }

    /* 浮动客服 */
    .floating-service {
      position: fixed;
      right: 20px;
      bottom: 30px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }
    .float-btn {
      width: 50px;
      height: 50px;
      border-radius: 50%;
      background: var(--btn-gradient);
      color: #ffffff;
      border: none;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 4px 14px rgba(0, 0, 0, 0.25);
      cursor: pointer;
      text-decoration: none;
      font-size: 13px;
      font-weight: 700;
    }

    /* 响应式样式 */
    @media (max-width: 992px) {
      .hero-title {
        font-size: 30px;
      }
      .grid-4, .step-list {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-3 {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    @media (max-width: 768px) {
      .header-actions .btn-outline {
        display: none;
      }
      .mobile-menu-toggle {
        display: block;
      }
      .nav-links {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        width: 100%;
        background: #ffffff;
        flex-direction: column;
        padding: 16px 20px;
        border-bottom: 1px solid var(--border-color);
        box-shadow: 0 8px 20px rgba(0, 0, 0, 0.05);
      }
      .nav-links.show {
        display: flex;
      }
      .hero-data-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-3, .grid-2, .step-list {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .hero-title {
        font-size: 24px;
      }
    }