/* roulang page: index */
:root {
      --primary-deep: #1A1A2E;
      --accent-pink: #E94560;
      --gold: #F0A500;
      --bg-light: #F8F9FC;
      --white: #FFFFFF;
      --text-dark: #2D3436;
      --text-muted: #636E72;
      --success-green: #00B894;
      --border-light: #EDF2F7;
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-sm: 0 4px 20px rgba(26, 26, 46, 0.06);
      --shadow-hover: 0 12px 32px rgba(26, 26, 46, 0.12);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, sans-serif;
      --font-mono: "Inter", "Segoe UI", system-ui;
      --transition: 0.25s ease;
      --nav-height: 72px;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-light);
      color: var(--text-dark);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

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

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

    button, .btn {
      cursor: pointer;
      font-family: var(--font-sans);
      border: none;
      outline: none;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    @media (max-width: 640px) {
      .container {
        padding: 0 16px;
      }
    }

    /* 导航区域 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(12px);
      box-shadow: 0 1px 0 rgba(0,0,0,0.04);
      z-index: 1000;
      display: flex;
      align-items: center;
      transition: background var(--transition);
    }

    .header .container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }

    .logo {
      font-size: 1.8rem;
      font-weight: 800;
      letter-spacing: -0.5px;
      color: var(--primary-deep);
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo span {
      color: var(--accent-pink);
    }

    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }

    .nav-menu a {
      font-weight: 500;
      color: var(--text-dark);
      position: relative;
      padding: 4px 0;
      font-size: 0.95rem;
    }

    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent-pink);
      transition: width var(--transition);
    }

    .nav-menu a:hover::after,
    .nav-menu a.active::after {
      width: 100%;
    }

    .btn-primary {
      background: var(--accent-pink);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: background var(--transition), box-shadow var(--transition);
      box-shadow: 0 0 20px rgba(233, 69, 96, 0.25);
      border: none;
      font-size: 0.95rem;
      height: 48px;
    }

    .btn-primary:hover {
      background: #C73650;
      box-shadow: 0 0 24px rgba(233, 69, 96, 0.4);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary-deep);
      color: var(--primary-deep);
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: all var(--transition);
      height: 48px;
      display: inline-flex;
      align-items: center;
    }
    .btn-outline:hover {
      background: var(--primary-deep);
      color: white;
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      border: none;
      cursor: pointer;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--primary-deep);
      border-radius: 2px;
      transition: var(--transition);
    }

    @media (max-width: 768px) {
      .nav-menu {
        position: fixed;
        top: var(--nav-height);
        left: 0;
        width: 100%;
        height: calc(100vh - var(--nav-height));
        background: rgba(255,255,255,0.98);
        backdrop-filter: blur(20px);
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 28px;
        transform: translateX(100%);
        transition: transform 0.3s ease;
        z-index: 999;
      }
      .nav-menu.active {
        transform: translateX(0);
      }
      .hamburger {
        display: flex;
      }
      .desktop-cta {
        display: none;
      }
    }

    /* Hero */
    .hero {
      padding: calc(var(--nav-height) + 40px) 0 60px;
      background: var(--bg-light);
      position: relative;
      overflow: hidden;
      min-height: 85vh;
      display: flex;
      align-items: center;
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 60px;
      flex-wrap: wrap;
    }
    .hero-content {
      flex: 1 1 400px;
      position: relative;
      z-index: 2;
    }
    .hero h1 {
      font-size: 3rem;
      font-weight: 800;
      color: var(--primary-deep);
      line-height: 1.2;
      margin-bottom: 20px;
    }
    .hero .subtitle {
      font-size: 1.1rem;
      color: var(--text-muted);
      margin-bottom: 32px;
      max-width: 480px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-image {
      flex: 1 1 400px;
      position: relative;
      border-radius: 24px;
      overflow: hidden;
      box-shadow: var(--shadow-hover);
    }
    .hero-image img {
      width: 100%;
      height: auto;
      object-fit: cover;
      aspect-ratio: 4/3;
    }
    .hero-image::after {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(26,26,46,0.2) 0%, transparent 60%);
    }

    @media (max-width: 768px) {
      .hero .container {
        flex-direction: column;
        text-align: center;
      }
      .hero h1 {
        font-size: 2.4rem;
      }
      .hero-buttons {
        justify-content: center;
      }
    }

    /* 通用板块 */
    section {
      padding: 80px 0;
    }
    .section-title {
      font-size: 2.2rem;
      font-weight: 700;
      margin-bottom: 16px;
      color: var(--primary-deep);
    }
    .section-desc {
      color: var(--text-muted);
      margin-bottom: 48px;
      font-size: 1.1rem;
    }

    /* 数据亮点 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .stat-card {
      background: var(--white);
      padding: 32px 20px;
      border-radius: var(--radius-card);
      text-align: center;
      border-bottom: 4px solid var(--gold);
      box-shadow: var(--shadow-sm);
    }
    .stat-number {
      font-size: 2.8rem;
      font-weight: 800;
      color: var(--accent-pink);
      font-family: var(--font-mono);
    }
    .stat-label {
      color: var(--text-muted);
      margin-top: 8px;
    }

    @media (max-width: 768px) {
      .stats-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    /* 服务卡片 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .service-card {
      background: var(--white);
      padding: 32px 24px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-light);
      transition: all var(--transition);
    }
    .service-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .service-icon {
      width: 64px;
      height: 64px;
      background: #F8F9FC;
      border-radius: 50%;
      margin-bottom: 24px;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .service-card h3 {
      font-size: 1.4rem;
      margin-bottom: 12px;
    }
    .text-link {
      color: var(--accent-pink);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }
    @media (max-width: 1024px) {
      .services-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 640px) {
      .services-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 深色数据区 */
    .dark-bg {
      background: var(--primary-deep);
      color: white;
      border-radius: 24px;
      padding: 60px 40px;
      display: flex;
      gap: 40px;
      flex-wrap: wrap;
      align-items: center;
    }
    .dark-bg .left {
      flex: 1;
    }
    .dark-bg .right {
      flex: 1;
      display: flex;
      gap: 20px;
    }
    .chart-placeholder {
      background: rgba(255,255,255,0.08);
      border-radius: 16px;
      padding: 40px 20px;
      text-align: center;
      color: var(--gold);
    }

    /* 案例卡片 */
    .cases-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 16px;
    }
    .case-card {
      min-width: 260px;
      background: white;
      border-radius: var(--radius-card);
      padding: 24px;
      box-shadow: var(--shadow-sm);
      flex-shrink: 0;
    }
    .tag {
      background: rgba(240,165,0,0.1);
      color: var(--gold);
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 0.8rem;
      font-weight: 600;
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-question {
      width: 100%;
      background: transparent;
      padding: 18px 0;
      font-weight: 600;
      font-size: 1.1rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
      text-align: left;
      color: var(--primary-deep);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      background: #F8F9FC;
      padding: 0 16px;
      border-left: 3px solid transparent;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 16px;
      border-left-color: var(--accent-pink);
    }

    .cta-banner {
      background: var(--primary-deep);
      text-align: center;
      padding: 80px 24px;
      color: white;
      border-radius: 32px;
    }

    footer {
      background: var(--primary-deep);
      color: #B2BEC3;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }