/* roulang page: index */
:root {
      --primary: #FF6B35;
      --primary-dark: #E55A2B;
      --primary-light: #FF8C42;
      --secondary: #1A1A2E;
      --secondary-light: #16213E;
      --accent: #00C9A7;
      --bg: #F9FAFB;
      --card-bg: #FFFFFF;
      --text: #1F2937;
      --text-muted: #6B7280;
      --white: #FFFFFF;
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.06);
      --shadow-md: 0 8px 30px rgba(0,0,0,0.12);
      --shadow-btn: 0 6px 18px rgba(255,107,53,0.35);
      --radius-lg: 16px;
      --radius-md: 12px;
      --radius-btn: 30px;
      --radius-sm: 8px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", system-ui, sans-serif;
      --container-max: 1200px;
      --transition: 0.25s ease;
    }

    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      scroll-behavior: smooth;
    }

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

    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition);
    }

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

    /* 导航 */
    .nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: var(--white);
      box-shadow: 0 1px 8px rgba(0,0,0,0.05);
      z-index: 100;
      height: 64px;
      display: flex;
      align-items: center;
    }

    .nav .container {
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 22px;
      color: var(--primary);
    }

    .logo-icon {
      font-size: 26px;
      line-height: 1;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
    }

    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text);
      transition: color var(--transition);
    }

    .nav-links a:hover {
      color: var(--primary);
    }

    .btn-nav {
      background: var(--primary);
      color: var(--white) !important;
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      box-shadow: var(--shadow-btn);
      transition: background var(--transition), transform 0.2s;
      display: inline-block;
    }

    .btn-nav:hover {
      background: var(--primary-dark);
      transform: translateY(-1px);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      cursor: pointer;
    }

    .hamburger span {
      width: 24px;
      height: 2.5px;
      background: var(--text);
      border-radius: 2px;
      transition: 0.3s;
    }

    /* 移动端导航 */
    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 75%;
        max-width: 300px;
        height: 100vh;
        background: var(--white);
        flex-direction: column;
        padding: 100px 32px 40px;
        box-shadow: -5px 0 20px rgba(0,0,0,0.1);
        transition: right 0.35s ease;
        gap: 28px;
        align-items: flex-start;
      }

      .nav-links.active {
        right: 0;
      }

      .hamburger {
        display: flex;
        z-index: 110;
      }

      .nav-links .btn-nav {
        width: 100%;
        text-align: center;
      }
    }

    /* Hero */
    .hero {
      padding: 130px 0 80px;
      background: linear-gradient(180deg, #FFF5F0 0%, #F9FAFB 100%);
    }

    .hero .container {
      display: flex;
      align-items: center;
      gap: 50px;
      flex-wrap: wrap;
    }

    .hero-content {
      flex: 1;
      min-width: 280px;
    }

    .hero-content h1 {
      font-size: 36px;
      font-weight: 700;
      line-height: 1.2;
      color: var(--text);
      margin-bottom: 16px;
    }

    .hero-content .subtitle {
      font-size: 18px;
      color: var(--text-muted);
      margin-bottom: 32px;
      line-height: 1.5;
    }

    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: linear-gradient(135deg, #FF6B35 0%, #FF8C42 100%);
      color: var(--white);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      border: none;
      cursor: pointer;
      box-shadow: var(--shadow-btn);
      transition: transform 0.2s, box-shadow 0.2s, filter 0.2s;
      display: inline-block;
    }

    .btn-primary:hover {
      transform: scale(1.03);
      box-shadow: 0 8px 24px rgba(255,107,53,0.45);
      filter: brightness(1.02);
    }

    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      transition: background 0.2s, color 0.2s;
    }

    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }

    .hero-image {
      flex: 1;
      min-width: 280px;
    }

    .hero-image img {
      border-radius: 20px;
      box-shadow: var(--shadow-md);
      width: 100%;
    }

    /* 通用板块 */
    .section {
      padding: 80px 0;
    }

    .section-title {
      font-size: 28px;
      font-weight: 700;
      text-align: center;
      margin-bottom: 16px;
    }

    .section-sub {
      text-align: center;
      color: var(--text-muted);
      margin-bottom: 48px;
      font-size: 16px;
    }

    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .card {
      background: var(--card-bg);
      border-radius: var(--radius-lg);
      padding: 28px 24px;
      box-shadow: var(--shadow-sm);
      transition: transform 0.2s, box-shadow 0.2s;
    }

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

    .card-icon {
      font-size: 36px;
      color: var(--accent);
      margin-bottom: 16px;
    }

    .card h3 {
      font-size: 20px;
      margin-bottom: 10px;
      font-weight: 600;
    }

    .feature-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .scene-card {
      border-radius: var(--radius-lg);
      overflow: hidden;
      background: var(--card-bg);
      box-shadow: var(--shadow-sm);
      transition: 0.2s;
    }

    .scene-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-md);
    }

    .scene-img {
      position: relative;
      height: 200px;
      overflow: hidden;
    }

    .scene-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }

    .scene-tag {
      position: absolute;
      bottom: 12px;
      left: 12px;
      background: rgba(0,0,0,0.65);
      color: white;
      padding: 6px 15px;
      border-radius: 20px;
      font-size: 14px;
      backdrop-filter: blur(4px);
    }

    .stats {
      display: flex;
      justify-content: center;
      gap: 40px;
      flex-wrap: wrap;
      margin: 30px 0;
    }

    .stat-badge {
      background: var(--accent);
      color: white;
      padding: 20px 30px;
      border-radius: 60px;
      font-weight: 700;
      font-size: 22px;
      text-align: center;
      min-width: 140px;
    }

    .faq-item {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      margin-bottom: 12px;
      box-shadow: var(--shadow-sm);
    }

    .faq-question {
      padding: 18px 24px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      cursor: pointer;
      user-select: none;
    }

    .faq-icon {
      font-size: 22px;
      color: var(--primary);
      transition: 0.3s;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      background: #F9FAFB;
      padding: 0 24px;
      transition: max-height 0.3s ease, padding 0.3s;
      color: var(--text-muted);
    }

    .faq-item.open .faq-answer {
      max-height: 180px;
      padding: 16px 24px;
    }

    .cta-section {
      background: linear-gradient(135deg, #1A1A2E 0%, #16213E 100%);
      padding: 80px 0;
      text-align: center;
    }

    .cta-section h2 {
      color: white;
      font-size: 32px;
      margin-bottom: 16px;
    }

    .footer {
      background: #1A1A2E;
      color: #E5E7EB;
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 30px;
    }

    .footer a {
      color: #CBD5E1;
      font-size: 14px;
      margin-bottom: 8px;
      display: block;
    }

    .copyright {
      margin-top: 40px;
      text-align: center;
      color: #9CA3AF;
      font-size: 14px;
    }

    @media (max-width: 1024px) {
      .grid-3, .feature-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    @media (max-width: 768px) {
      .hero .container {
        flex-direction: column;
        text-align: center;
      }
      .hero-buttons {
        justify-content: center;
      }
      .grid-3, .feature-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }