/* roulang page: index */
:root {
      --primary-deep: #2E1A47;
      --primary-mid: #6C3A8B;
      --accent-orange: #E94E1F;
      --accent-orange-dark: #C43D15;
      --bg-warm: #FDFAF6;
      --text-main: #333333;
      --text-muted: #6B6B7B;
      --card-bg: #FFFFFF;
      --border-light: rgba(108, 58, 139, 0.1);
      --shadow-sm: 0 4px 20px rgba(46, 26, 71, 0.06);
      --shadow-hover: 0 12px 30px rgba(46, 26, 71, 0.12);
      --radius-card: 12px;
      --radius-btn: 50px;
      --transition: 0.3s ease;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-warm);
      color: var(--text-main);
      line-height: 1.7;
      font-weight: 400;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition);
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 卡片化导航面板 */
    .navbar-card {
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(10px);
      border-radius: 16px;
      box-shadow: 0 4px 15px rgba(0,0,0,0.05);
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 24px;
      height: 72px;
      max-width: 1200px;
      margin: 20px auto 0;
      position: sticky;
      top: 20px;
      z-index: 1000;
      border: 1px solid rgba(108,58,139,0.08);
    }
    .logo-area {
      font-weight: 800;
      font-size: 1.6rem;
      color: var(--primary-deep);
      letter-spacing: -0.5px;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo-area i {
      color: var(--accent-orange);
      font-size: 2rem;
    }
    .nav-links {
      display: flex;
      gap: 8px;
      align-items: center;
      flex-wrap: wrap;
    }
    .nav-item {
      background: transparent;
      padding: 8px 14px;
      border-radius: 40px;
      font-weight: 500;
      font-size: 0.95rem;
      color: var(--primary-deep);
      display: flex;
      align-items: center;
      gap: 6px;
      transition: all var(--transition);
    }
    .nav-item i {
      font-size: 1rem;
      color: var(--primary-mid);
    }
    .nav-item:hover {
      color: var(--accent-orange);
      background: rgba(233,78,31,0.05);
    }
    .cta-btn {
      background: var(--accent-orange);
      color: white;
      padding: 10px 24px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 0.95rem;
      transition: background var(--transition);
      white-space: nowrap;
    }
    .cta-btn:hover {
      background: var(--accent-orange-dark);
    }
    .hamburger {
      display: none;
      font-size: 1.8rem;
      cursor: pointer;
      color: var(--primary-deep);
    }
    /* Hero */
    .hero-section {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 40px;
      padding: 80px 0 100px;
    }
    .hero-left {
      flex: 1 1 50%;
    }
    .hero-left h1 {
      font-size: 3.5rem;
      font-weight: 800;
      line-height: 1.2;
      letter-spacing: -1px;
      color: var(--primary-deep);
      margin-bottom: 24px;
    }
    .hero-left .subtitle {
      font-size: 1.2rem;
      color: var(--text-muted);
      margin-bottom: 36px;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--accent-orange);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
    }
    .btn-outline {
      border: 1px solid var(--primary-mid);
      color: var(--primary-deep);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      background: transparent;
    }
    .btn-outline:hover {
      background: rgba(108,58,139,0.05);
    }
    .hero-right {
      flex: 1 1 45%;
      position: relative;
    }
    .hero-right img {
      border-radius: 24px;
      box-shadow: var(--shadow-hover);
      width: 100%;
    }
    .hero-glow {
      position: absolute;
      width: 300px;
      height: 300px;
      background: radial-gradient(circle, rgba(233,78,31,0.15) 0%, transparent 70%);
      top: -20px;
      right: -20px;
      z-index: -1;
    }
    section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 2.5rem;
      font-weight: 700;
      color: var(--primary-deep);
      text-align: center;
      margin-bottom: 16px;
    }
    .title-decor {
      width: 60px;
      height: 4px;
      background: var(--accent-orange);
      margin: 0 auto 48px;
      border-radius: 2px;
    }
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .feature-card, .product-card, .scenario-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-light);
      transition: all var(--transition);
    }
    .feature-card:hover, .product-card:hover, .scenario-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .feature-icon {
      font-size: 2.2rem;
      color: var(--primary-mid);
      margin-bottom: 20px;
    }
    .card-title {
      font-size: 1.25rem;
      font-weight: 600;
      color: var(--primary-deep);
      margin-bottom: 12px;
    }
    .product-img {
      width: 100%;
      height: 180px;
      object-fit: cover;
      border-radius: 8px;
      margin-bottom: 20px;
    }
    .tag {
      color: var(--accent-orange);
      font-weight: 600;
      font-size: 0.9rem;
    }
    .scenario-card img {
      border-radius: 8px;
      height: 140px;
      object-fit: cover;
      margin-bottom: 16px;
    }
    .data-board {
      display: flex;
      justify-content: center;
      gap: 60px;
      flex-wrap: wrap;
      text-align: center;
    }
    .data-number {
      font-size: 3rem;
      font-weight: 800;
      color: var(--accent-orange);
    }
    .faq-item {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 24px;
      margin-bottom: 16px;
      box-shadow: var(--shadow-sm);
      cursor: pointer;
      display: flex;
      align-items: center;
      gap: 16px;
      transition: background var(--transition);
    }
    .faq-item i {
      color: var(--accent-orange);
      font-size: 1.2rem;
    }
    .faq-content {
      flex:1;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-muted);
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      margin-top: 12px;
    }
    .cta-section {
      background: var(--primary-deep);
      text-align: center;
      border-radius: 24px;
      padding: 80px 24px;
      color: white;
    }
    .footer {
      background: #2E1A47;
      color: #D1C4E9;
      padding: 60px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 30px;
    }
    .footer h4 {
      color: white;
      margin-bottom: 16px;
    }
    .footer a:hover {
      color: var(--accent-orange);
    }
    .copyright {
      background: #1F1233;
      text-align: center;
      padding: 16px;
      margin-top: 40px;
      font-size: 0.9rem;
    }
    @media (max-width: 1024px) {
      .hero-section {
        flex-direction: column;
      }
      .grid-3 {
        grid-template-columns: repeat(2,1fr);
      }
    }
    @media (max-width: 768px) {
      .navbar-card {
        flex-wrap: wrap;
        height: auto;
        padding: 16px;
      }
      .nav-links {
        display: none;
        width: 100%;
        flex-direction: column;
        margin-top: 12px;
      }
      .nav-links.active {
        display: flex;
      }
      .hamburger {
        display: block;
      }
      .hero-left h1 {
        font-size: 2.2rem;
      }
      .section-title {
        font-size: 1.8rem;
      }
      .grid-3 {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: repeat(2,1fr);
      }
      .data-board {
        gap: 24px;
      }
    }
    @media (max-width: 520px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }