* {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    :root {
      --rose: #e63f6b;
      --rose-deep: #c22e56;
      --rose-soft: #fdecf1;
      --rose-glow: #ffb3c6;
      --ink: #1f1a1c;
      --ink-soft: #4a3f42;
      --ink-muted: #74666a;
      --paper: #fffafb;
      --white: #ffffff;
      --border: #f0d9e0;
      --shadow: 0 18px 40px -22px rgba(210, 50, 90, 0.25);
      --radius: 22px;
      --font: 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Noto Sans SC', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
      --container: 1180px;
      --gap: 24px;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      background: linear-gradient(180deg, #fff6f9 0%, #ffffff 45%, #fff4f8 100%);
      color: var(--ink);
      font-family: var(--font);
      line-height: 1.6;
      min-height: 100vh;
      padding: 0 20px;
    }
    .ai-container {
      width: 100%;
      max-width: var(--container);
      margin-left: auto;
      margin-right: auto;
      padding-left: 0;
      padding-right: 0;
    }
    /* 全局按钮 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      padding: 13px 32px;
      border-radius: 999px;
      font-weight: 600;
      font-size: 1rem;
      text-decoration: none;
      border: 1px solid transparent;
      cursor: pointer;
      transition: transform .18s ease, box-shadow .25s ease, background .2s, color .2s;
      white-space: nowrap;
      letter-spacing: .3px;
      line-height: 1.2;
    }
    .btn-primary {
      background: var(--rose);
      color: #fff;
      box-shadow: 0 10px 22px -8px rgba(230, 63, 107, .45);
    }
    .btn-primary:hover {
      background: var(--rose-deep);
      transform: translateY(-2px);
      box-shadow: 0 18px 28px -12px rgba(230, 63, 107, .55);
    }
    .btn-outline {
      border-color: var(--rose);
      background: rgba(255,255,255,.6);
      color: var(--rose-deep);
    }
    .btn-outline:hover {
      background: var(--rose-soft);
      transform: translateY(-2px);
    }
    .btn-light {
      background: rgba(255,255,255,.9);
      color: var(--ink);
      border: 1px solid var(--border);
      box-shadow: 0 6px 16px -12px rgba(0,0,0,.12);
    }
    .btn-light:hover {
      background: #fff;
      border-color: var(--rose-light);
      transform: translateY(-2px);
    }
    .btn-sm {
      padding: 9px 22px;
      font-size: .875rem;
    }
    /* 导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 60;
      backdrop-filter: blur(8px);
      background: rgba(255, 248, 250, .86);
      border-bottom: 1px solid rgba(240, 217, 224, .7);
      padding: 12px 0;
      margin-bottom: 8px;
    }
    .nav-bar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 10px;
    }
    .brand {
      display: flex;
      align-items: center;
      gap: 10px;
      text-decoration: none;
    }
    .ai-page-logo {
      width: 40px;
      height: auto;
      display: block;
      border-radius: 10px;
    }
    .brand-text {
      font-weight: 700;
      font-size: 1.25rem;
      color: var(--ink);
      letter-spacing: .5px;
    }
    .brand-text span {
      color: var(--rose);
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 0;
      flex-wrap: wrap;
      list-style: none;
      margin: 0;
      padding: 0;
    }
    .nav-links li {
      margin: 0;
      padding: 0 10px;
    }
    .nav-links a {
      font-size: .94rem;
      color: var(--ink-soft);
      text-decoration: none;
      font-weight: 500;
      padding: 6px 0;
      position: relative;
      transition: color .2s;
      white-space: nowrap;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      left: 0;
      right: 0;
      bottom: -4px;
      height: 2px;
      background: var(--rose);
      border-radius: 4px;
      transform: scaleX(0);
      transform-origin: left;
      transition: transform .25s ease;
    }
    .nav-links a:hover {
      color: var(--rose);
    }
    .nav-links a:hover::after {
      transform: scaleX(1);
    }
    .nav-extra {
      display: flex;
      align-items: center;
      gap: 10px;
    }
    .menu-toggle {
      display: none;
      background: transparent;
      border: 1px solid var(--border);
      border-radius: 10px;
      font-size: 1.5rem;
      line-height: 1;
      padding: 6px 12px;
      color: var(--ink);
      cursor: pointer;
      transition: background .2s;
    }
    .menu-toggle:hover {
      background: var(--rose-soft);
    }
    /* 首屏 hero */
    .hero {
      position: relative;
      padding: 48px 0 40px;
      margin-bottom: 10px;
      overflow: hidden;
      border-radius: 0 0 48px 48px;
      background: radial-gradient(circle at 15% 30%, rgba(253, 231, 238, .9), transparent 55%),
                  radial-gradient(circle at 90% 20%, rgba(255, 223, 233, .7), transparent 50%),
                  linear-gradient(135deg, #fff5f8 0%, #ffffff 80%);
    }
    .hero::after {
      content: '';
      position: absolute;
      inset: 0;
      background-image: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Ccircle cx='4' cy='4' r='2' fill='%23fbd3df' opacity='0.5'/%3E%3C/svg%3E");
      opacity: .5;
      pointer-events: none;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 760px;
    }
    .hero-tag {
      display: inline-block;
      background: rgba(230, 63, 107, .12);
      color: var(--rose-deep);
      font-size: .85rem;
      font-weight: 600;
      letter-spacing: .6px;
      padding: 6px 18px;
      border-radius: 999px;
      margin-bottom: 22px;
      border: 1px solid rgba(230, 63, 107, .2);
    }
    .hero h1 {
      font-size: clamp(2.2rem, 5vw, 3.6rem);
      line-height: 1.2;
      font-weight: 800;
      color: var(--ink);
      margin-bottom: 20px;
      letter-spacing: -.5px;
    }
    .hero h1 .accent {
      color: var(--rose);
      position: relative;
      display: inline-block;
    }
    .hero h1 .accent::after {
      content: '';
      position: absolute;
      left: 0;
      right: 0;
      bottom: 6px;
      height: 10px;
      background: rgba(230, 63, 107, .18);
      border-radius: 6px;
      z-index: -1;
    }
    .hero-desc {
      font-size: 1.2rem;
      color: var(--ink-soft);
      max-width: 600px;
      margin-bottom: 32px;
    }
    .hero-actions {
      display: flex;
      flex-wrap: wrap;
      gap: 14px;
      align-items: center;
      margin-bottom: 48px;
    }
    .hero-stats {
      display: flex;
      flex-wrap: wrap;
      gap: 30px 48px;
      padding-top: 20px;
      border-top: 1px solid rgba(240, 217, 224, .8);
    }
    .hero-stat-item {
      display: flex;
      flex-direction: column;
    }
    .hero-stat-num {
      font-size: 1.9rem;
      font-weight: 800;
      color: var(--rose-deep);
      line-height: 1.2;
      letter-spacing: -.5px;
    }
    .hero-stat-label {
      font-size: .87rem;
      color: var(--ink-muted);
    }
    /* 区块标题 */
    .section {
      padding: 58px 0 48px;
    }
    .section-head {
      text-align: center;
      max-width: 720px;
      margin: 0 auto 40px;
    }
    .section-eyebrow {
      display: inline-block;
      font-size: .82rem;
      font-weight: 600;
      text-transform: uppercase;
      letter-spacing: 2px;
      color: var(--rose);
      background: var(--rose-soft);
      padding: 5px 16px;
      border-radius: 999px;
      margin-bottom: 14px;
    }
    .section-title {
      font-size: clamp(1.8rem, 4vw, 2.4rem);
      font-weight: 700;
      color: var(--ink);
      line-height: 1.3;
      margin-bottom: 14px;
    }
    .section-sub {
      color: var(--ink-muted);
      font-size: 1.05rem;
    }
    /* 卡片网格 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: var(--gap);
      align-items: stretch;
    }
    .grid-2 {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: var(--gap);
      align-items: stretch;
    }
    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: var(--gap);
    }
    .card {
      background: var(--white);
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 28px 24px;
      box-shadow: 0 4px 18px -12px rgba(0,0,0,.08);
      transition: transform .25s ease, box-shadow .3s ease, border-color .2s;
      display: flex;
      flex-direction: column;
      height: 100%;
    }
    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow);
      border-color: var(--rose-glow);
    }
    .card-icon {
      width: 48px;
      height: 48px;
      background: var(--rose-soft);
      border-radius: 14px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 18px;
      font-size: 1.5rem;
      color: var(--rose);
    }
    .card h3 {
      font-size: 1.2rem;
      margin-bottom: 8px;
      color: var(--ink);
      font-weight: 700;
    }
    .card p {
      font-size: .95rem;
      color: var(--ink-muted);
      flex: 1;
    }
    .card-tag {
      display: inline-block;
      margin-top: 16px;
      font-size: .8rem;
      color: var(--rose-deep);
      background: var(--rose-soft);
      padding: 3px 12px;
      border-radius: 999px;
      align-self: flex-start;
    }
    /* 平台介绍双列 */
    .platform-intro {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
    }
    .intro-highlight {
      background: linear-gradient(145deg, #fff4f8, #fff);
      border: 1px solid var(--border);
      border-radius: 28px;
      padding: 32px;
    }
    .intro-highlight h3 {
      font-size: 1.6rem;
      margin-bottom: 16px;
      color: var(--ink);
    }
    .intro-highlight p {
      color: var(--ink-soft);
      margin-bottom: 24px;
    }
    .intro-list {
      list-style: none;
    }
    .intro-list li {
      display: flex;
      gap: 12px;
      align-items: flex-start;
      margin-bottom: 18px;
      color: var(--ink-soft);
      font-size: .98rem;
    }
    .intro-list .mark {
      color: var(--rose);
      font-weight: 800;
      font-size: 1.2rem;
      line-height: 1.3;
      flex-shrink: 0;
    }
    /* 服务能力卡片 */
    .service-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 20px;
    }
    .service-item {
      background: #fff;
      border-radius: 20px;
      border: 1px solid var(--border);
      padding: 22px 20px;
      transition: all .25s;
      display: flex;
      flex-direction: column;
    }
    .service-item:hover {
      border-color: var(--rose-glow);
      background: #fffafc;
      box-shadow: var(--shadow);
    }
    .service-item h4 {
      font-size: 1.05rem;
      color: var(--ink);
      margin-bottom: 6px;
      font-weight: 700;
    }
    .service-item p {
      font-size: .9rem;
      color: var(--ink-muted);
      flex: 1;
    }
    /* 流程步骤 */
    .steps {
      display: flex;
      gap: 16px;
      counter-reset: step;
      flex-wrap: wrap;
      justify-content: center;
    }
    .step {
      flex: 1 1 180px;
      background: #fff;
      border-radius: 60px 20px 20px 60px;
      padding: 20px 22px 20px 76px;
      position: relative;
      border: 1px solid var(--border);
      counter-increment: step;
      transition: transform .2s, box-shadow .2s;
      min-width: 180px;
    }
    .step::before {
      content: counter(step);
      position: absolute;
      left: 16px;
      top: 50%;
      transform: translateY(-50%);
      width: 44px;
      height: 44px;
      background: var(--rose);
      color: #fff;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      font-size: 1.2rem;
      box-shadow: 0 6px 16px -6px rgba(230, 63, 107, .5);
    }
    .step h4 {
      font-size: 1rem;
      margin-bottom: 4px;
      color: var(--ink);
    }
    .step p {
      font-size: .85rem;
      color: var(--ink-muted);
    }
    .step:hover {
      transform: translateY(-3px);
      box-shadow: var(--shadow);
    }
    /* 对比评测卡片 */
    .compare-section {
      background: linear-gradient(135deg, #fff6f9, #fff);
      border-radius: 36px;
      padding: 48px 32px;
      border: 1px solid #f7dce4;
      margin: 20px 0 0;
    }
    .rating-big {
      display: flex;
      align-items: baseline;
      gap: 8px;
      justify-content: center;
      margin-bottom: 24px;
      flex-wrap: wrap;
    }
    .rating-score {
      font-size: 4rem;
      font-weight: 900;
      line-height: 1;
      color: var(--rose-deep);
      letter-spacing: -1px;
    }
    .rating-full {
      font-size: 1.4rem;
      color: var(--ink-muted);
    }
    .rating-stars {
      color: #f5b342;
      font-size: 1.8rem;
      letter-spacing: 4px;
    }
    .table-wrap {
      width: 100%;
      overflow-x: auto;
      border-radius: 20px;
      border: 1px solid var(--border);
      background: #fff;
      margin-top: 20px;
    }
    table {
      width: 100%;
      border-collapse: collapse;
      min-width: 640px;
      font-size: .95rem;
    }
    th, td {
      padding: 16px 20px;
      text-align: left;
      border-bottom: 1px solid #f5e4eb;
      color: var(--ink);
    }
    th {
      background: #fef7fa;
      font-weight: 700;
      color: var(--rose-deep);
      font-size: .9rem;
      letter-spacing: .3px;
    }
    tr:last-child td {
      border-bottom: none;
    }
    tr:hover td {
      background: #fffafc;
    }
    /* FAQ */
    .faq-list {
      display: flex;
      flex-direction: column;
      gap: 12px;
      max-width: 860px;
      margin: 0 auto;
    }
    .faq-item {
      background: #fff;
      border: 1px solid var(--border);
      border-radius: 16px;
      overflow: hidden;
      transition: box-shadow .2s;
    }
    .faq-question {
      width: 100%;
      padding: 18px 24px;
      background: transparent;
      border: none;
      text-align: left;
      font-size: 1rem;
      font-weight: 600;
      color: var(--ink);
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      gap: 16px;
      line-height: 1.4;
    }
    .faq-question:hover {
      background: #fff9fb;
    }
    .faq-question .arrow {
      transition: transform .25s;
      color: var(--rose);
      font-size: 1.1rem;
    }
    .faq-item.open .faq-question .arrow {
      transform: rotate(180deg);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height .3s ease, padding .2s;
      padding: 0 24px;
      color: var(--ink-soft);
      font-size: .95rem;
      background: #fff;
    }
    .faq-item.open .faq-answer {
      max-height: 220px;
      padding: 0 24px 20px;
    }
    /* 用户评论 */
    .review-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 20px;
    }
    .review-card {
      background: #fff;
      border-radius: 24px;
      border: 1px solid var(--border);
      padding: 26px 22px;
      transition: transform .2s, box-shadow .2s;
    }
    .review-card:hover {
      transform: translateY(-3px);
      box-shadow: var(--shadow);
    }
    .review-head {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 16px;
    }
    .review-avatar {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: linear-gradient(145deg, #fbd3df, #fdeef3);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      color: var(--rose-deep);
      font-size: 1.1rem;
    }
    .review-name {
      font-weight: 700;
      font-size: .96rem;
      color: var(--ink);
    }
    .review-role {
      font-size: .8rem;
      color: var(--ink-muted);
    }
    .review-stars {
      color: #f5b342;
      font-size: .9rem;
      letter-spacing: 2px;
      margin-bottom: 8px;
    }
    .review-text {
      font-size: .93rem;
      color: var(--ink-soft);
      line-height: 1.7;
    }
    /* 案例展示 */
    .case-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }
    .case-card {
      display: flex;
      flex-direction: column;
      background: #fff;
      border-radius: 24px;
      border: 1px solid var(--border);
      overflow: hidden;
      transition: transform .25s, box-shadow .25s;
    }
    .case-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow);
    }
    .case-img-wrap {
      background: #fdf2f6;
      padding: 28px;
      display: flex;
      justify-content: center;
      align-items: center;
      min-height: 180px;
    }
    .case-img-wrap img {
      max-width: 100%;
      height: auto;
      max-height: 200px;
      border-radius: 12px;
      object-fit: contain;
      display: block;
    }
    .case-body {
      padding: 20px 22px 24px;
      flex: 1;
      display: flex;
      flex-direction: column;
    }
    .case-body h3 {
      font-size: 1.15rem;
      margin-bottom: 6px;
    }
    .case-body p {
      font-size: .9rem;
      color: var(--ink-muted);
      flex: 1;
    }
    .case-link {
      margin-top: 14px;
      color: var(--rose);
      font-weight: 600;
      font-size: .9rem;
      text-decoration: none;
      align-self: flex-start;
    }
    .case-link:hover {
      text-decoration: underline;
    }
    /* 文章列表 & 标签 */
    .articles-tags-wrap {
      display: grid;
      grid-template-columns: 3fr 2fr;
      gap: 40px;
      align-items: start;
    }
    .article-list {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 14px;
    }
    .article-list li a {
      display: flex;
      justify-content: space-between;
      align-items: center;
      gap: 16px;
      text-decoration: none;
      color: var(--ink-soft);
      font-size: .96rem;
      border-bottom: 1px dashed #f0d9e0;
      padding-bottom: 12px;
      transition: color .2s, border-color .2s;
    }
    .article-list li a:hover {
      color: var(--rose);
      border-color: var(--rose-glow);
    }
    .article-list .date {
      font-size: .8rem;
      color: var(--ink-muted);
      white-space: nowrap;
    }
    .tag-cloud {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
    }
    .tag-cloud span {
      background: #fff;
      border: 1px solid var(--border);
      padding: 6px 16px;
      border-radius: 999px;
      font-size: .85rem;
      color: var(--ink-soft);
      transition: background .2s, color .2s, border-color .2s;
      cursor: default;
    }
    .tag-cloud span:hover {
      background: var(--rose-soft);
      color: var(--rose-deep);
      border-color: var(--rose-glow);
    }
    /* 表单 */
    .form-card {
      background: #fff;
      border-radius: 28px;
      border: 1px solid var(--border);
      padding: 32px;
      box-shadow: 0 10px 30px -24px rgba(0,0,0,.15);
    }
    .form-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 18px;
    }
    .form-group {
      display: flex;
      flex-direction: column;
      gap: 6px;
    }
    .form-group.full {
      grid-column: 1 / -1;
    }
    .form-group label {
      font-size: .9rem;
      font-weight: 600;
      color: var(--ink-soft);
    }
    .form-group input,
    .form-group select,
    .form-group textarea {
      padding: 12px 16px;
      border: 1px solid var(--border);
      border-radius: 14px;
      font-size: .95rem;
      font-family: var(--font);
      background: #fefafb;
      color: var(--ink);
      transition: border-color .2s, box-shadow .2s;
      outline: none;
      width: 100%;
    }
    .form-group input:focus,
    .form-group select:focus,
    .form-group textarea:focus {
      border-color: var(--rose);
      box-shadow: 0 0 0 4px rgba(230,63,107,.1);
      background: #fff;
    }
    .form-group textarea {
      resize: vertical;
      min-height: 100px;
    }
    .form-actions {
      grid-column: 1 / -1;
      display: flex;
      justify-content: flex-start;
      margin-top: 6px;
    }
    /* footer */
    .site-footer {
      background: #2b1e22;
      color: #f5e9ed;
      border-radius: 36px 36px 0 0;
      padding: 48px 0 24px;
      margin-top: 40px;
      width: 100%;
    }
    .footer-inner {
      width: 100%;
      max-width: var(--container);
      margin: 0 auto;
      padding: 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1.4fr 1.6fr;
      gap: 32px;
      align-items: start;
    }
    .footer-brand .brand-text {
      color: #fff;
    }
    .footer-brand p {
      color: #d9c2ca;
      font-size: .9rem;
      margin: 14px 0 12px;
    }
    .footer-contact a {
      color: #ffb3c6;
      text-decoration: none;
      font-size: .9rem;
      display: block;
      margin-bottom: 6px;
    }
    .footer-contact a:hover {
      text-decoration: underline;
    }
    .footer-links-col h4,
    .footer-qr-col h4 {
      color: #fff;
      font-size: .95rem;
      margin-bottom: 16px;
      font-weight: 600;
    }
    .footer-links-col ul {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 8px;
    }
    .footer-links-col ul a {
      color: #d6bfc7;
      text-decoration: none;
      font-size: .88rem;
      transition: color .2s;
    }
    .footer-links-col ul a:hover {
      color: #ffb3c6;
    }
    .footer-qr-col img {
      width: 100px;
      height: 100px;
      border-radius: 10px;
      background: #fff;
      padding: 5px;
      object-fit: contain;
      display: block;
      margin-bottom: 10px;
    }
    .footer-qr-col p {
      font-size: .8rem;
      color: #b9a0a8;
    }
    .footer-bottom {
      border-top: 1px solid rgba(255,255,255,.08);
      margin-top: 36px;
      padding-top: 22px;
      text-align: center;
      font-size: .85rem;
      color: #b299a2;
    }
    /* 浮动客服 */
    .float-service {
      position: fixed;
      right: 20px;
      bottom: 80px;
      z-index: 80;
      display: flex;
      flex-direction: column;
      gap: 10px;
      align-items: center;
    }
    .float-btn {
      width: 54px;
      height: 54px;
      border-radius: 50%;
      background: #fff;
      box-shadow: 0 8px 20px -8px rgba(0,0,0,.25);
      display: flex;
      align-items: center;
      justify-content: center;
      border: 1px solid var(--border);
      color: var(--rose-deep);
      font-size: 1.4rem;
      text-decoration: none;
      transition: transform .2s, box-shadow .2s;
      cursor: pointer;
    }
    .float-btn:hover {
      transform: translateY(-3px);
      box-shadow: 0 16px 26px -10px rgba(230,63,107,.3);
      background: var(--rose-soft);
    }
    .float-qr-pop {
      display: none;
      position: absolute;
      right: 64px;
      bottom: 0;
      background: #fff;
      border: 1px solid var(--border);
      border-radius: 16px;
      padding: 14px;
      box-shadow: var(--shadow);
    }
    .float-service:hover .float-qr-pop {
      display: block;
    }
    .float-qr-pop img {
      width: 120px;
      height: auto;
      display: block;
      border-radius: 8px;
    }
    .back-top {
      position: fixed;
      right: 20px;
      bottom: 20px;
      z-index: 80;
      width: 46px;
      height: 46px;
      border-radius: 50%;
      background: var(--rose);
      color: #fff;
      border: none;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.2rem;
      cursor: pointer;
      box-shadow: 0 6px 16px -6px rgba(230,63,107,.6);
      opacity: 0;
      visibility: hidden;
      transition: opacity .25s, visibility .25s, transform .2s;
    }
    .back-top.show {
      opacity: 1;
      visibility: visible;
    }
    .back-top:hover {
      transform: translateY(-3px);
      background: var(--rose-deep);
    }
    /* 动画 */
    .reveal {
      opacity: 0;
      transform: translateY(18px);
      transition: opacity .6s ease, transform .6s ease;
    }
    .reveal.visible {
      opacity: 1;
      transform: translateY(0);
    }
    @media (prefers-reduced-motion: reduce) {
      .reveal { opacity: 1; transform: none; transition: none; }
      * { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
    }
    /* 响应式 */
    @media (max-width: 1024px) {
      .grid-3, .grid-4, .service-grid, .review-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: 28px;
      }
      .platform-intro {
        grid-template-columns: 1fr;
      }
      .articles-tags-wrap {
        grid-template-columns: 1fr;
      }
    }
    @media (max-width: 780px) {
      body { padding: 0 14px; }
      .nav-links {
        display: none;
        width: 100%;
        flex-direction: column;
        align-items: flex-start;
        background: #fff;
        border-radius: 16px;
        padding: 12px 0;
        margin-top: 8px;
        border: 1px solid var(--border);
        box-shadow: var(--shadow);
      }
      .nav-links.open {
        display: flex;
      }
      .nav-links li {
        width: 100%;
        padding: 0;
      }
      .nav-links a {
        display: block;
        padding: 10px 20px;
      }
      .nav-links a::after {
        display: none;
      }
      .menu-toggle {
        display: block;
      }
      .hero {
        padding: 32px 0 28px;
      }
      .hero h1 {
        font-size: 2rem;
      }
      .grid-3, .grid-4, .service-grid, .review-grid, .form-grid, .case-grid {
        grid-template-columns: 1fr;
      }
      .compare-section {
        padding: 28px 16px;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .float-service {
        right: 12px;
        bottom: 70px;
      }
      .back-top {
        right: 12px;
        bottom: 16px;
      }
      .hero-stats {
        gap: 20px;
      }
      .step {
        flex: 1 1 100%;
      }
      .ai-container {
        padding-left: 0;
        padding-right: 0;
      }
    }
    @media (max-width: 480px) {
      .hero-actions .btn {
        width: 100%;
      }
      .hero-actions {
        flex-direction: column;
        align-items: stretch;
      }
      .card {
        padding: 22px 18px;
      }
    }