/* roulang page: index */
:root {
      --primary: #00E5FF;
      --primary-glow: rgba(0,229,255,0.35);
      --secondary-bg: #0A0F1E;
      --surface-dark: #0D1428;
      --surface-card: #1A2035;
      --accent: #FF3366;
      --text-primary: #FFFFFF;
      --text-secondary: rgba(255,255,255,0.8);
      --text-muted: rgba(255,255,255,0.55);
      --border-subtle: rgba(255,255,255,0.08);
      --border-glow: rgba(0,229,255,0.2);
      --radius-card: 20px;
      --radius-btn: 14px;
      --radius-input: 12px;
      --shadow-card: 0 10px 30px rgba(0,0,0,0.5);
      --shadow-glow: 0 0 25px rgba(0,229,255,0.2);
      --transition: 0.3s cubic-bezier(0.25, 0.8, 0.25, 1.2);
      --glass-bg: rgba(10,15,30,0.7);
      --glass-border: 1px solid rgba(0,229,255,0.18);
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: 'Inter', 'SF Pro Display', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      background-color: var(--secondary-bg);
      color: var(--text-primary);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
      background-image: linear-gradient(rgba(0,229,255,0.02) 1px, transparent 1px), linear-gradient(90deg, rgba(0,229,255,0.02) 1px, transparent 1px);
      background-size: 60px 60px;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }
    img {
      max-width: 100%;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    button, input {
      font-family: inherit;
    }
    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      height: 84px;
      display: flex;
      align-items: center;
      background: rgba(10,15,30,0.55);
      backdrop-filter: blur(18px);
      border-bottom: 1px solid rgba(0,229,255,0.12);
      transition: background 0.3s, box-shadow 0.3s;
    }
    .navbar.scrolled {
      background: rgba(10,15,30,0.85);
      box-shadow: 0 8px 24px rgba(0,0,0,0.4);
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--text-primary);
      letter-spacing: -0.5px;
    }
    .logo-icon {
      width: 32px;
      height: 32px;
      background: linear-gradient(135deg, var(--primary), #009FBF);
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: #0A0F1E;
      font-weight: 700;
      font-size: 1.3rem;
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 36px;
    }
    .nav-link {
      font-weight: 500;
      font-size: 0.95rem;
      color: var(--text-secondary);
      transition: color 0.2s;
      position: relative;
    }
    .nav-link:hover, .nav-link.active {
      color: var(--primary);
    }
    .nav-cta {
      background: var(--primary);
      color: #0A0F1E;
      padding: 10px 24px;
      border-radius: 30px;
      font-weight: 600;
      font-size: 0.9rem;
      transition: all 0.3s;
    }
    .nav-cta:hover {
      background: #33EAFF;
      box-shadow: 0 0 20px rgba(0,229,255,0.7);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      background: transparent;
      border: none;
      cursor: pointer;
    }
    .hamburger span {
      width: 26px;
      height: 2px;
      background: var(--text-primary);
      border-radius: 2px;
      transition: 0.3s;
    }
    .mobile-menu {
      position: fixed;
      top: 84px;
      left: 0;
      width: 100%;
      background: rgba(10,15,30,0.95);
      backdrop-filter: blur(20px);
      flex-direction: column;
      padding: 32px;
      gap: 24px;
      display: none;
      border-bottom: 1px solid var(--border-glow);
    }
    .mobile-menu.open {
      display: flex;
    }
    /* Hero */
    .hero {
      padding: 160px 0 100px;
      background: radial-gradient(circle at 30% 20%, rgba(0,229,255,0.12) 0%, transparent 60%);
      position: relative;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 48px;
    }
    .hero-content {
      flex: 1.2;
    }
    .hero h1 {
      font-size: 4rem;
      font-weight: 700;
      line-height: 1.2;
      background: linear-gradient(to right, #00E5FF, #FFFFFF);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      margin-bottom: 20px;
    }
    .hero-sub {
      font-size: 1.2rem;
      color: var(--text-secondary);
      margin-bottom: 36px;
      max-width: 540px;
    }
    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary);
      color: #0A0F1E;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      border: none;
      cursor: pointer;
      transition: var(--transition);
      box-shadow: 0 0 18px rgba(0,229,255,0.3);
    }
    .btn-primary:hover {
      background: #33EAFF;
      box-shadow: 0 0 35px rgba(0,229,255,0.7);
      transform: scale(1.04);
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--primary);
      color: var(--primary);
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: var(--transition);
    }
    .btn-outline:hover {
      background: rgba(0,229,255,0.1);
    }
    .hero-visual {
      flex: 1;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      min-height: 360px;
      border-radius: 28px;
      box-shadow: var(--shadow-glow);
      border: 1px solid var(--border-glow);
    }
    .trust-badges {
      margin-top: 50px;
      display: flex;
      align-items: center;
      gap: 32px;
      flex-wrap: wrap;
      color: var(--text-muted);
    }
    /* sections */
    section {
      padding: 100px 0;
    }
    .section-header {
      margin-bottom: 60px;
    }
    .section-header h2 {
      font-size: 2.5rem;
      font-weight: 700;
      margin-bottom: 12px;
    }
    .section-sub {
      color: var(--text-muted);
      font-size: 1rem;
    }
    .alt-bg {
      background-color: var(--surface-dark);
    }
    /* 优势交错 */
    .advantage-row {
      display: flex;
      align-items: center;
      gap: 64px;
      margin-bottom: 80px;
    }
    .advantage-text {
      flex: 1;
    }
    .advantage-text h3 {
      font-size: 2rem;
      color: var(--primary);
      margin-bottom: 16px;
    }
    .advantage-img {
      flex: 1;
      background: url('/assets/images/coverpic/cover-2.webp') center/cover no-repeat;
      height: 320px;
      border-radius: 24px;
      border: 1px solid var(--border-glow);
      box-shadow: 0 0 30px rgba(0,229,255,0.15);
    }
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 32px;
    }
    .service-card {
      background: var(--surface-card);
      padding: 32px;
      border-radius: var(--radius-card);
      border: 1px solid var(--border-subtle);
      transition: var(--transition);
    }
    .service-card:hover {
      transform: translateY(-8px);
      border-color: var(--primary);
      box-shadow: 0 16px 32px rgba(0,229,255,0.15);
    }
    .scenario-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 32px;
    }
    .scenario-card {
      background: var(--surface-card);
      border-radius: var(--radius-card);
      overflow: hidden;
      border: 1px solid var(--border-subtle);
      transition: var(--transition);
    }
    .scenario-card:hover {
      box-shadow: 0 20px 40px rgba(0,229,255,0.2);
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 24px;
      margin-bottom: 48px;
    }
    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
    }
    .faq-item {
      background: var(--surface-card);
      border-radius: 16px;
      padding: 20px;
      border-left: 3px solid transparent;
      transition: 0.3s;
    }
    .faq-item.active {
      border-left-color: var(--primary);
      background: rgba(0,229,255,0.05);
    }
    .cta-section {
      background: var(--surface-dark);
      text-align: center;
      padding: 90px 0;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    @media (max-width: 1024px) {
      .container { padding: 0 24px; }
      .hero-grid { flex-direction: column; }
      .services-grid { grid-template-columns: 1fr 1fr; }
      .stats-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      .nav-menu { display: none; }
      .hamburger { display: flex; }
      .hero h1 { font-size: 2.5rem; }
      .advantage-row { flex-direction: column; }
      .services-grid { grid-template-columns: 1fr; }
      .scenario-grid { grid-template-columns: 1fr; }
      .faq-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
    }