/* roulang page: index */
:root {
      --primary: #4E6EF2;
      --primary-dark: #3A5AD9;
      --secondary: #00B578;
      --bg: #F5F6FA;
      --surface: #FFFFFF;
      --text: #1F2329;
      --text-secondary: #86909C;
      --border: #E5E8EF;
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-card: 0 2px 12px rgba(0,0,0,0.04);
      --shadow-card-hover: 0 8px 24px rgba(0,0,0,0.08);
      --transition: 200ms ease-out;
      --container: 1200px;
      --page-gutter: 24px;
      --section-gap: 80px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: -apple-system, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      background: var(--bg);
      color: var(--text);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      outline: none;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
    }
    .container {
      max-width: var(--container);
      margin: 0 auto;
      padding: 0 var(--page-gutter);
    }
    /* 导航 */
    .header {
      background: var(--surface);
      position: sticky;
      top: 0;
      z-index: 1000;
      border-bottom: 1px solid var(--border);
      backdrop-filter: blur(8px);
      background: rgba(255,255,255,0.92);
    }
    .nav-bar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 64px;
    }
    .logo {
      font-size: 22px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: 0.5px;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo-icon {
      width: 28px;
      height: 28px;
      background: var(--primary);
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 14px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }
    .nav-links a {
      font-size: 16px;
      font-weight: 500;
      color: var(--text);
      position: relative;
      padding: 4px 0;
      transition: color var(--transition);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width var(--transition);
    }
    .nav-links a:hover {
      color: var(--primary);
    }
    .nav-links a:hover::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      padding: 8px;
    }
    .hamburger span {
      display: block;
      width: 24px;
      height: 2px;
      background: var(--text);
      border-radius: 2px;
      transition: var(--transition);
    }
    /* Hero */
    .hero {
      background: linear-gradient(135deg, #F5F6FA 0%, #EDF0F8 100%);
      padding: 60px 0 40px;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-text {
      flex: 1;
    }
    .hero-text h1 {
      font-size: 44px;
      font-weight: 700;
      line-height: 1.3;
      color: var(--text);
      margin-bottom: 20px;
    }
    .hero-text .subtitle {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 32px;
      line-height: 1.6;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
    }
    .btn-primary:hover {
      background: var(--primary-dark);
    }
    .btn-secondary {
      background: #F0F2F5;
      color: var(--text);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
    }
    .btn-secondary:hover {
      background: #E5E8EF;
    }
    .hero-visual {
      flex: 1;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: var(--radius-card);
      min-height: 340px;
      box-shadow: var(--shadow-card);
      background-color: #dce1f0;
    }
    .metrics-bar {
      display: flex;
      justify-content: center;
      gap: 48px;
      margin-top: 40px;
      background: var(--surface);
      padding: 28px 40px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
    }
    .metric-item {
      text-align: center;
    }
    .metric-number {
      font-size: 32px;
      font-weight: 700;
      color: var(--primary);
    }
    .metric-label {
      font-size: 14px;
      color: var(--text-secondary);
      margin-top: 4px;
    }
    /* Section 通用 */
    section {
      padding: var(--section-gap) 0;
    }
    .section-title {
      font-size: 32px;
      font-weight: 600;
      margin-bottom: 16px;
      color: var(--text);
      text-align: center;
    }
    .section-sub {
      color: var(--text-secondary);
      font-size: 16px;
      text-align: center;
      margin-bottom: 48px;
      max-width: 640px;
      margin-left: auto;
      margin-right: auto;
    }
    /* 功能分组 */
    .feature-row {
      display: flex;
      flex-direction: column;
      gap: 48px;
    }
    .feature-item {
      display: flex;
      align-items: center;
      gap: 48px;
      background: var(--surface);
      padding: 32px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .feature-item:hover {
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-2px);
    }
    .feature-img {
      width: 40%;
      aspect-ratio: 4/3;
      background: #EAF0FE;
      border-radius: var(--radius-card);
      background-size: cover;
      background-position: center;
    }
    .feature-content {
      flex: 1;
    }
    .feature-content h3 {
      font-size: 22px;
      font-weight: 600;
      margin-bottom: 12px;
    }
    .feature-content p {
      color: var(--text-secondary);
      margin-bottom: 12px;
    }
    .feature-list {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 8px;
    }
    .feature-list li::before {
      content: "✓";
      color: var(--secondary);
      font-weight: bold;
      margin-right: 8px;
    }
    /* 场景 2x2 */
    .scenes-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }
    .scene-card {
      background: var(--surface);
      border-radius: var(--radius-card);
      padding: 24px;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      text-align: center;
    }
    .scene-card:hover {
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-2px);
    }
    .scene-img {
      width: 100%;
      aspect-ratio: 16/10;
      background: #eef1fb;
      border-radius: var(--radius-card);
      margin-bottom: 20px;
      background-size: cover;
      background-position: center;
      transition: transform 0.3s ease;
    }
    .scene-card:hover .scene-img {
      transform: scale(1.02);
    }
    .scene-card h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 8px;
    }
    /* 案例卡片 */
    .cases-scroll {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .case-card {
      background: var(--surface);
      border-radius: var(--radius-card);
      padding: 24px;
      box-shadow: var(--shadow-card);
      border-left: 4px solid var(--primary);
      transition: var(--transition);
    }
    .case-card:hover {
      box-shadow: var(--shadow-card-hover);
    }
    .case-company {
      font-weight: 600;
      font-size: 18px;
    }
    .case-stat {
      font-size: 28px;
      font-weight: 700;
      color: var(--secondary);
      margin: 12px 0;
    }
    .case-quote {
      color: var(--text-secondary);
    }
    /* 价格 */
    .pricing-grid {
      display: flex;
      gap: 24px;
      justify-content: center;
      flex-wrap: wrap;
    }
    .pricing-card {
      background: var(--surface);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-card);
      flex: 1;
      min-width: 260px;
      max-width: 340px;
      transition: var(--transition);
      position: relative;
    }
    .pricing-card.featured {
      border: 2px solid var(--primary);
      transform: scale(1.02);
    }
    .pricing-card:hover {
      box-shadow: var(--shadow-card-hover);
    }
    .price-amount {
      font-size: 36px;
      font-weight: 700;
      color: var(--primary);
    }
    /* FAQ 双列手风琴 */
    .faq-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 16px;
      align-items: start;
    }
    .faq-item {
      background: var(--surface);
      border-radius: var(--radius-card);
      padding: 16px 20px;
      box-shadow: var(--shadow-card);
      cursor: pointer;
    }
    .faq-question {
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-secondary);
      margin-top: 0;
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      margin-top: 12px;
    }
    .faq-item.open .faq-question {
      color: var(--primary);
    }
    /* CTA 底部 */
    .cta-block {
      background: var(--primary);
      color: white;
      text-align: center;
      padding: 60px 24px;
      border-radius: var(--radius-card);
      margin: 0 var(--page-gutter);
    }
    .cta-block h2 {
      font-size: 32px;
      font-weight: 700;
      margin-bottom: 16px;
    }
    .btn-light {
      background: white;
      color: var(--primary);
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      margin-top: 24px;
    }
    /* Footer */
    .footer {
      background: #1F2329;
      color: #cccccc;
      padding: 48px 0 24px;
    }
    .footer-grid {
      display: flex;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 32px;
    }
    .footer-col h4 {
      color: white;
      margin-bottom: 12px;
    }
    .footer-col a {
      display: block;
      color: #9aa0b0;
      margin-bottom: 8px;
      font-size: 14px;
    }
    .footer-bottom {
      border-top: 1px solid #333;
      margin-top: 32px;
      padding-top: 24px;
      display: flex;
      justify-content: space-between;
      font-size: 14px;
      color: #86909C;
    }
    /* 响应式 */
    @media (max-width: 1024px) {
      .cases-scroll { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero-grid { flex-direction: column; }
      .hero-visual { min-height: 240px; width: 100%; }
      .feature-item { flex-direction: column; }
      .feature-img { width: 100%; }
      .scenes-grid { grid-template-columns: 1fr; }
      .cases-scroll { grid-template-columns: 1fr; }
      .faq-grid { grid-template-columns: 1fr; }
      .metrics-bar { flex-wrap: wrap; gap: 24px; }
      .pricing-grid { flex-direction: column; align-items: center; }
      .footer-grid { flex-direction: column; }
    }