/* roulang page: index */
:root {
      --primary: #0A8F3C;
      --primary-soft: rgba(10, 143, 60, 0.1);
      --secondary: #F04E23;
      --secondary-soft: rgba(240, 78, 35, 0.1);
      --deep-black: #0F1419;
      --frost-white: #F5F7FA;
      --card-white: #FFFFFF;
      --text-dark: #1E2A35;
      --text-muted: #5F6B7A;
      --border-light: rgba(0,0,0,0.04);
      --shadow-card: 0 2px 12px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.08);
      --radius-card: 16px;
      --radius-btn: 10px;
      --radius-pill: 30px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", system-ui, -apple-system, sans-serif;
      --font-number: "Inter", "DIN Alternate", "PingFang SC", sans-serif;
      --transition: all 0.2s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--frost-white);
      color: var(--text-dark);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }
    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(255,255,255,0.96);
      backdrop-filter: blur(10px);
      box-shadow: 0 1px 0 rgba(0,0,0,0.05);
      z-index: 1000;
      height: 64px;
      display: flex;
      align-items: center;
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }
    .logo {
      font-weight: 700;
      font-size: 1.4rem;
      color: var(--primary);
      text-decoration: none;
      display: flex;
      align-items: center;
      gap: 6px;
      letter-spacing: -0.3px;
      white-space: nowrap;
    }
    .logo span {
      color: var(--text-dark);
      font-weight: 500;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      text-decoration: none;
      color: var(--text-muted);
      font-weight: 500;
      font-size: 0.95rem;
      transition: var(--transition);
      position: relative;
    }
    .nav-links a:hover {
      color: var(--primary);
    }
    .nav-cta {
      background: var(--primary);
      color: white !important;
      padding: 10px 20px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      box-shadow: 0 4px 10px rgba(10,143,60,0.2);
    }
    .nav-cta:hover {
      background: var(--secondary) !important;
      color: white !important;
      box-shadow: 0 6px 14px rgba(240,78,35,0.3);
      transform: translateY(-1px);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
      padding: 8px;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--text-dark);
      border-radius: 4px;
      transition: 0.2s;
    }
    /* 移动端菜单 */
    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 64px;
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        padding: 32px 24px;
        gap: 24px;
        box-shadow: 0 10px 25px rgba(0,0,0,0.05);
        transform: translateY(-120%);
        opacity: 0;
        transition: 0.25s ease;
        pointer-events: none;
      }
      .nav-links.active {
        transform: translateY(0);
        opacity: 1;
        pointer-events: auto;
      }
      .hamburger {
        display: flex;
      }
      .nav-cta {
        align-self: flex-start;
      }
    }
    /* 区块间距 */
    section {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
    }
    h2 {
      font-size: 28px;
      font-weight: 600;
      line-height: 1.3;
      margin-bottom: 16px;
      color: var(--text-dark);
    }
    .section-sub {
      color: var(--text-muted);
      font-size: 1.1rem;
      margin-bottom: 48px;
      max-width: 600px;
    }
    /* Hero */
    #hero {
      min-height: 100vh;
      background: linear-gradient(135deg, #0F1419 0%, rgba(10,143,60,0.2) 100%), url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      display: flex;
      align-items: center;
      color: white;
      padding-top: 64px;
      position: relative;
    }
    .hero-content {
      display: flex;
      flex-direction: column;
      gap: 24px;
      max-width: 700px;
    }
    .hero h1 {
      font-size: 42px;
      font-weight: 700;
      line-height: 1.2;
      color: white;
    }
    .hero .sub {
      font-size: 1.2rem;
      color: rgba(255,255,255,0.85);
      line-height: 1.6;
    }
    .hero-badges {
      display: flex;
      flex-wrap: wrap;
      gap: 20px;
      margin: 20px 0 10px;
    }
    .badge {
      background: rgba(255,255,255,0.08);
      backdrop-filter: blur(8px);
      border-radius: 20px;
      padding: 12px 22px;
      border: 1px solid rgba(255,255,255,0.2);
      color: white;
      display: flex;
      align-items: baseline;
      gap: 8px;
    }
    .badge .num {
      font-family: var(--font-number);
      font-size: 2rem;
      font-weight: 700;
      color: var(--secondary);
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
      margin-top: 8px;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      text-decoration: none;
      transition: var(--transition);
      border: none;
      cursor: pointer;
      display: inline-block;
    }
    .btn-primary:hover {
      background: var(--secondary);
      transform: translateY(-2px);
      box-shadow: 0 12px 24px rgba(240,78,35,0.25);
    }
    .btn-outline {
      border: 1.5px solid white;
      background: transparent;
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      text-decoration: none;
      transition: var(--transition);
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.1);
    }
    /* 卡片通用 */
    .card {
      background: var(--card-white);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    /* 功能网格 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .feature-icon {
      width: 64px;
      height: 64px;
      background: var(--primary-soft);
      border-radius: 18px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--primary);
      font-size: 28px;
    }
    .card h3 {
      font-size: 20px;
      margin-bottom: 12px;
    }
    .text-link {
      color: var(--primary);
      font-weight: 600;
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }
    .text-link:hover {
      color: var(--secondary);
      text-decoration: underline;
    }
    /* 场景卡片 */
    .scene-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .scene-card {
      border-radius: var(--radius-card);
      overflow: hidden;
      position: relative;
      height: 260px;
      background-size: cover;
      background-position: center;
    }
    .scene-overlay {
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      background: linear-gradient(transparent, rgba(0,0,0,0.7));
      padding: 24px;
      color: white;
    }
    .tag {
      background: var(--secondary);
      color: white;
      padding: 4px 14px;
      border-radius: 20px;
      font-size: 0.8rem;
      font-weight: 600;
      display: inline-block;
      margin-bottom: 8px;
    }
    /* 数据案例 */
    .stats-row {
      display: flex;
      gap: 32px;
      justify-content: center;
      flex-wrap: wrap;
    }
    .stat-item {
      text-align: center;
      min-width: 150px;
    }
    .stat-number {
      font-family: var(--font-number);
      font-size: 48px;
      font-weight: 700;
      color: var(--primary);
    }
    /* FAQ */
    .faq-grid {
      display: flex;
      gap: 48px;
      align-items: flex-start;
    }
    .faq-left {
      flex: 1;
    }
    .faq-right {
      flex: 2;
      display: flex;
      flex-direction: column;
      gap: 16px;
    }
    .faq-item {
      background: white;
      border-radius: 12px;
      padding: 20px 24px;
      cursor: pointer;
      box-shadow: 0 2px 8px rgba(0,0,0,0.02);
      border: 1px solid #eee;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      font-weight: 600;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: 0.3s;
      color: var(--text-muted);
      margin-top: 0;
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      margin-top: 12px;
    }
    /* CTA 底部 */
    #cta {
      background: var(--deep-black);
      color: white;
      text-align: center;
    }
    #cta h2 {
      color: white;
    }
    /* 页脚 */
    footer {
      background: var(--deep-black);
      color: #ccc;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer-links a {
      color: #aaa;
      text-decoration: none;
      display: block;
      margin-bottom: 8px;
    }
    .copyright {
      border-top: 1px solid #2a2a2a;
      margin-top: 40px;
      padding-top: 20px;
      text-align: center;
      color: #777;
    }
    @media (max-width: 768px) {
      .grid-3, .scene-grid, .footer-grid {
        grid-template-columns: 1fr;
      }
      .faq-grid {
        flex-direction: column;
      }
      .hero h1 {
        font-size: 32px;
      }
    }