/* roulang page: index */
:root {
      --primary-deep: #0B0E17;
      --secondary-bg: #131824;
      --accent-orange: #FF6B2B;
      --glow-cyan: #00E5FF;
      --text-primary: #F0F2F5;
      --text-secondary: #8892A6;
      --success-green: #00C48C;
      --warning-red: #FF4D4D;
      --card-glass-bg: rgba(19, 24, 36, 0.7);
      --card-border: rgba(0, 229, 255, 0.15);
      --card-hover-border: rgba(0, 229, 255, 0.4);
      --shadow-card: 0 8px 32px rgba(0,0,0,0.4);
      --shadow-glow: 0 16px 48px rgba(0,229,255,0.15);
      --radius-lg: 16px;
      --radius-md: 12px;
      --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --transition-smooth: 0.25s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--primary-deep);
      color: var(--text-primary);
      line-height: 1.7;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      padding: 16px 0;
      transition: background var(--transition-smooth), backdrop-filter var(--transition-smooth), border var(--transition-smooth);
      background: transparent;
      backdrop-filter: blur(0px);
      border-bottom: 1px solid transparent;
    }
    .navbar.scrolled {
      background: rgba(11, 14, 23, 0.85);
      backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(0, 229, 255, 0.2);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 800;
      font-size: 1.5rem;
      color: var(--text-primary);
      text-decoration: none;
      letter-spacing: -0.5px;
    }
    .logo i {
      color: var(--accent-orange);
      font-size: 1.8rem;
      filter: drop-shadow(0 0 6px rgba(255,107,43,0.6));
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
    }
    .nav-links a {
      color: var(--text-secondary);
      text-decoration: none;
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
      padding: 4px 0;
      transition: color var(--transition-smooth);
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--glow-cyan);
    }
    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--glow-cyan);
      box-shadow: 0 0 10px var(--glow-cyan);
    }
    .nav-cta {
      background: var(--accent-orange);
      color: white;
      padding: 10px 20px;
      border-radius: 30px;
      font-weight: 700;
      font-size: 0.9rem;
      text-decoration: none;
      transition: background var(--transition-smooth), box-shadow var(--transition-smooth);
      box-shadow: 0 0 16px rgba(255,107,43,0.3);
    }
    .nav-cta:hover {
      background: #FF7F50;
      box-shadow: 0 0 24px rgba(255,107,43,0.6);
    }
    .hamburger {
      display: none;
      background: none;
      border: none;
      color: var(--text-primary);
      font-size: 1.8rem;
      cursor: pointer;
    }
    /* 板块间距 */
    section {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
      .nav-links {
        display: none;
      }
      .hamburger {
        display: block;
      }
      .mobile-menu {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background: rgba(11,14,23,0.98);
        backdrop-filter: blur(30px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 32px;
        z-index: 999;
      }
      .mobile-menu.active {
        display: flex;
      }
      .mobile-menu a {
        font-size: 1.8rem;
        color: var(--text-primary);
        text-decoration: none;
        font-weight: 600;
      }
    }
    /* Hero */
    .hero {
      padding-top: 140px;
      padding-bottom: 80px;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
    }
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(90deg, rgba(11,14,23,0.9) 0%, rgba(11,14,23,0.6) 100%);
    }
    .hero .container {
      position: relative;
      z-index: 2;
      display: flex;
      align-items: center;
      gap: 40px;
    }
    .hero-text {
      flex: 1;
    }
    .hero-text h1 {
      font-weight: 800;
      font-size: clamp(2.5rem, 6vw, 4rem);
      line-height: 1.2;
      letter-spacing: -0.02em;
      margin-bottom: 20px;
    }
    .hero-text h1 span {
      color: var(--accent-orange);
    }
    .hero-sub {
      font-size: 1.2rem;
      color: var(--text-secondary);
      margin-bottom: 32px;
    }
    .hero-stats {
      display: flex;
      gap: 32px;
      margin-bottom: 36px;
    }
    .stat-item h3 {
      font-weight: 800;
      font-size: 2rem;
      color: var(--glow-cyan);
    }
    .stat-item p {
      color: var(--text-secondary);
      font-size: 0.9rem;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--accent-orange);
      color: white;
      padding: 14px 32px;
      border-radius: 30px;
      font-weight: 700;
      text-decoration: none;
      transition: all 0.25s;
      box-shadow: 0 0 20px rgba(255,107,43,0.4);
      border: none;
      cursor: pointer;
      display: inline-block;
    }
    .btn-primary:hover {
      background: #FF7F50;
      box-shadow: 0 0 30px rgba(255,107,43,0.7);
    }
    .btn-outline {
      border: 1.5px solid var(--glow-cyan);
      color: var(--glow-cyan);
      padding: 14px 32px;
      border-radius: 30px;
      font-weight: 700;
      text-decoration: none;
      background: transparent;
      transition: all 0.25s;
    }
    .btn-outline:hover {
      background: rgba(0,229,255,0.1);
      box-shadow: 0 0 20px rgba(0,229,255,0.3);
    }
    .hero-visual {
      flex: 1;
      background: rgba(19,24,36,0.6);
      backdrop-filter: blur(20px);
      border-radius: 24px;
      padding: 30px;
      border: 1px solid rgba(0,229,255,0.2);
    }
    @media (max-width: 1024px) {
      .hero .container {
        flex-direction: column;
      }
      .hero-visual {
        width: 100%;
      }
    }
    /* 卡片通用 */
    .glass-card {
      background: var(--card-glass-bg);
      backdrop-filter: blur(16px);
      border-radius: var(--radius-lg);
      border: 1px solid var(--card-border);
      box-shadow: var(--shadow-card);
      transition: all 0.3s ease;
      padding: 32px;
    }
    .glass-card:hover {
      box-shadow: var(--shadow-glow);
      border-color: var(--card-hover-border);
    }
    .section-title {
      font-weight: 700;
      font-size: clamp(1.8rem, 4vw, 2.5rem);
      margin-bottom: 16px;
      text-align: center;
    }
    .grid-2 {
      display: grid;
      grid-template-columns: repeat(2,1fr);
      gap: 24px;
    }
    @media (max-width: 768px) {
      .grid-2 {
        grid-template-columns: 1fr;
      }
    }
    .feature-row {
      display: flex;
      align-items: center;
      gap: 40px;
      margin-bottom: 60px;
    }
    .feature-row.reverse {
      flex-direction: row-reverse;
    }
    .feature-img {
      flex: 1;
      border-radius: 12px;
      overflow: hidden;
      position: relative;
    }
    .feature-img img {
      width: 100%;
      display: block;
      border-radius: 12px;
    }
    .tag {
      background: rgba(0,229,255,0.15);
      color: var(--glow-cyan);
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 0.8rem;
      font-weight: 600;
      display: inline-block;
      margin-bottom: 8px;
    }
    .scenario-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
      align-items: center;
    }
    .pricing-card.featured {
      transform: scale(1.05);
      border-color: var(--accent-orange);
      box-shadow: 0 0 32px rgba(255,107,43,0.4);
    }
    @media (max-width: 768px) {
      .feature-row, .feature-row.reverse {
        flex-direction: column;
      }
      .scenario-grid, .pricing-grid {
        grid-template-columns: 1fr;
      }
      .pricing-card.featured {
        transform: none;
      }
    }
    .faq-grid {
      display: grid;
      grid-template-columns: repeat(2,1fr);
      gap: 16px;
    }
    details {
      background: var(--secondary-bg);
      border-radius: 12px;
      padding: 16px 20px;
      cursor: pointer;
    }
    summary {
      font-weight: 600;
      list-style: none;
      display: flex;
      justify-content: space-between;
    }
    .cta-final {
      background: #0B0E17 radial-gradient(circle at 30% 30%, rgba(255,107,43,0.2), transparent);
      text-align: center;
    }
    footer {
      background: #0B0E17;
      border-top: 1px solid rgba(255,255,255,0.05);
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }