/* roulang page: index */
:root {
      --primary: #E33B1C;
      --primary-dark: #c02f16;
      --secondary: #1A1A2E;
      --accent: #F5A623;
      --bg: #FAFAFA;
      --card-bg: #FFFFFF;
      --text-main: #1A1A2E;
      --text-light: #5A5A72;
      --border-light: rgba(255,255,255,0.18);
      --shadow-card: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 12px 28px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 8px;
      --transition: 0.25s ease;
      --glass-bg: rgba(26, 26, 46, 0.75);
      --backdrop-blur: blur(12px);
    }
    * {
      box-sizing: border-box;
    }
    body {
      margin: 0;
      font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
      background-color: var(--bg);
      color: var(--text-main);
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding-left: 40px;
      padding-right: 40px;
    }
    @media (max-width: 768px) {
      .container {
        padding-left: 20px;
        padding-right: 20px;
      }
    }
    h1, h2, h3, h4 {
      font-weight: 700;
      letter-spacing: -0.02em;
      line-height: 1.3;
    }
    h1 {
      font-size: 3.5rem;
    }
    h2 {
      font-size: 2rem;
      margin-bottom: 1.5rem;
    }
    h3 {
      font-size: 1.25rem;
    }
    p {
      margin-bottom: 1.5rem;
      color: var(--text-light);
      font-weight: 400;
    }
    .section-padding {
      padding: 80px 0;
    }
    @media (max-width: 768px) {
      h1 {
        font-size: 2.25rem;
      }
      h2 {
        font-size: 1.8rem;
      }
      .section-padding {
        padding: 60px 0;
      }
    }

    /* 导航 */
    .glass-nav {
      background: var(--glass-bg);
      backdrop-filter: var(--backdrop-blur);
      -webkit-backdrop-filter: var(--backdrop-blur);
      border-bottom: 1px solid var(--border-light);
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 50;
      transition: background 0.3s ease, box-shadow 0.3s ease;
    }
    .nav-solid {
      background: #1A1A2E;
      box-shadow: 0 4px 20px rgba(0,0,0,0.2);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo-text {
      font-weight: 800;
      font-size: 1.7rem;
      color: white;
      letter-spacing: -0.01em;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo-icon {
      color: var(--primary);
      font-size: 2rem;
    }
    .nav-links {
      display: flex;
      gap: 2rem;
      align-items: center;
    }
    .nav-links a {
      color: rgba(255,255,255,0.85);
      text-decoration: none;
      font-weight: 500;
      font-size: 0.95rem;
      transition: color 0.2s;
      letter-spacing: 0.3px;
    }
    .nav-links a:hover {
      color: var(--accent);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      border: none;
      cursor: pointer;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: white;
      border-radius: 2px;
      transition: 0.3s;
    }
    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: #1A1A2E;
        flex-direction: column;
        padding: 20px;
        gap: 16px;
        border-bottom: 1px solid rgba(255,255,255,0.15);
      }
      .nav-links.active {
        display: flex;
      }
      .hamburger {
        display: flex;
      }
    }

    /* 按钮 */
    .btn-primary {
      background: var(--primary);
      color: white;
      border: none;
      padding: 0.85rem 2.2rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 1rem;
      cursor: pointer;
      transition: background 0.2s, box-shadow 0.2s;
      box-shadow: 0 6px 14px rgba(227, 59, 28, 0.25);
      display: inline-block;
      text-decoration: none;
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      box-shadow: inset 0 2px 6px rgba(0,0,0,0.2), 0 8px 18px rgba(227, 59, 28, 0.3);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 0.75rem 2rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: 0.25s;
      text-decoration: none;
      display: inline-block;
    }
    .btn-outline:hover {
      background: rgba(227, 59, 28, 0.08);
    }

    /* Hero 数据卡片 */
    .stat-card {
      background: rgba(255,255,255,0.08);
      backdrop-filter: blur(10px);
      border-radius: 16px;
      padding: 1.2rem 1.5rem;
      text-align: center;
      color: white;
    }
    .stat-number {
      font-size: 2.2rem;
      font-weight: 800;
      color: var(--accent);
      line-height: 1.2;
    }
    .service-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      transition: transform var(--transition), box-shadow var(--transition);
      overflow: hidden;
      display: flex;
      flex-direction: column;
    }
    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .card-img {
      height: 180px;
      background-size: cover;
      background-position: center;
      transition: transform 0.4s ease;
    }
    .service-card:hover .card-img {
      transform: scale(1.03);
    }
    .faq-item {
      border-bottom: 1px solid #e2e8f0;
      padding: 1.2rem 0;
    }
    .faq-question {
      font-weight: 700;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      color: var(--text-light);
    }
    .faq-icon {
      transition: transform 0.3s;
    }
    .rotate-icon {
      transform: rotate(45deg);
    }
    footer {
      background: #1A1A2E;
      color: #ddd;
    }