/* roulang page: index */
:root {
      --primary-deep: #0A1A2F;
      --primary-dark: #051020;
      --accent-cyan: #00D4AA;
      --accent-orange: #FF6B35;
      --glass-bg: rgba(255, 255, 255, 0.05);
      --glass-border: rgba(255, 255, 255, 0.1);
      --text-white: #FFFFFF;
      --text-body: #B0C4DE;
      --text-muted: #7B8FA1;
      --shadow-glow: 0 0 24px rgba(0, 212, 170, 0.5);
      --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.3);
      --border-radius-lg: 16px;
      --border-radius-md: 8px;
      --border-radius-pill: 20px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --font-data: "Inter", "Roboto", sans-serif;
      --transition: 0.3s ease;
      --container-max: 1200px;
    }

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

    body {
      font-family: var(--font-sans);
      background: radial-gradient(circle at 20% 10%, #0A1A2F, #051020);
      color: var(--text-body);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      position: relative;
    }

    body::before {
      content: "";
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1200 800" opacity="0.08"><path d="M200 150 L400 50 L600 150 L800 50 L1000 150 L1000 350 L800 450 L600 350 L400 450 L200 350 Z" fill="none" stroke="%2300D4AA" stroke-width="1.5"/><circle cx="300" cy="250" r="20" fill="none" stroke="%2300D4AA" stroke-width="1"/><circle cx="700" cy="400" r="35" fill="none" stroke="%2300D4AA" stroke-width="1"/><path d="M100 500 L300 600 L500 500 L700 600 L900 500" fill="none" stroke="%23ffffff" stroke-width="0.8"/></svg>');
      background-size: cover;
      pointer-events: none;
      z-index: 0;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 20px;
      position: relative;
      z-index: 1;
    }

    /* 导航栏 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(10, 26, 47, 0.85);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
      height: 72px;
      display: flex;
      align-items: center;
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 20px;
    }

    .logo-area {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--text-white);
      text-decoration: none;
    }
    .logo-icon {
      font-size: 1.8rem;
      color: var(--accent-cyan);
    }

    .nav-tabs {
      display: flex;
      gap: 4px;
      background: rgba(255,255,255,0.03);
      border-radius: 30px;
      padding: 4px;
    }

    .nav-chip {
      padding: 8px 20px;
      border-radius: 20px;
      color: var(--text-body);
      font-weight: 500;
      font-size: 0.95rem;
      transition: var(--transition);
      text-decoration: none;
      white-space: nowrap;
    }

    .nav-chip.active, .nav-chip:hover {
      background: var(--accent-cyan);
      color: #0A1A2F;
      font-weight: 600;
    }

    .cta-btn {
      background: var(--accent-cyan);
      color: #0A1A2F;
      font-weight: 700;
      padding: 12px 28px;
      border-radius: var(--border-radius-md);
      box-shadow: var(--shadow-glow);
      transition: var(--transition);
      text-decoration: none;
      display: inline-block;
      border: none;
      cursor: pointer;
    }
    .cta-btn:hover {
      box-shadow: 0 0 32px rgba(0,212,170,0.7);
      transform: translateY(-2px);
      color: #0A1A2F;
    }

    .hamburger {
      display: none;
      background: transparent;
      border: none;
      color: white;
      font-size: 1.8rem;
      cursor: pointer;
    }

    /* 移动端导航 */
    @media (max-width: 1024px) {
      .nav-tabs {
        display: none;
      }
      .hamburger {
        display: block;
      }
      .mobile-menu {
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: rgba(5, 16, 32, 0.96);
        backdrop-filter: blur(25px);
        flex-direction: column;
        padding: 24px;
        gap: 12px;
        display: none;
        z-index: 999;
        border-bottom: 1px solid rgba(255,255,255,0.1);
      }
      .mobile-menu.open {
        display: flex;
      }
      .mobile-menu .nav-chip {
        display: block;
        text-align: center;
        padding: 14px;
      }
    }

    section {
      padding: 100px 0;
      position: relative;
    }

    h2 {
      font-size: 36px;
      font-weight: 700;
      color: var(--text-white);
      margin-bottom: 16px;
    }
    .section-sub {
      color: var(--text-muted);
      font-size: 1.1rem;
      margin-bottom: 48px;
    }

    /* Hero */
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 40px;
      min-height: 90vh;
    }
    .hero-left {
      flex: 1;
    }
    .hero-right {
      flex: 1;
      background: rgba(255,255,255,0.03);
      border-radius: 20px;
      backdrop-filter: blur(10px);
      border: 1px solid rgba(255,255,255,0.1);
      overflow: hidden;
    }
    .hero-right img {
      width: 100%;
      height: auto;
      display: block;
    }
    h1 {
      font-size: 48px;
      font-weight: 800;
      color: white;
      line-height: 1.2;
      text-shadow: 0 0 30px rgba(0,212,170,0.3);
    }
    .btn-group {
      display: flex;
      gap: 16px;
      margin-top: 32px;
    }
    .btn-outline {
      background: transparent;
      border: 2px solid rgba(255,255,255,0.3);
      color: white;
      padding: 12px 28px;
      border-radius: 8px;
      font-weight: 600;
      transition: 0.3s;
    }
    .btn-outline:hover {
      border-color: var(--accent-cyan);
      color: var(--accent-cyan);
    }

    /* 卡片通用 */
    .glass-card {
      background: var(--glass-bg);
      backdrop-filter: blur(16px);
      border: 1px solid var(--glass-border);
      border-radius: var(--border-radius-lg);
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .glass-card:hover {
      border-color: rgba(0,212,170,0.4);
      transform: translateY(-4px);
    }

    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }

    .stat-number {
      font-family: var(--font-data);
      font-size: 40px;
      font-weight: 800;
      color: var(--accent-orange);
    }

    .waterfall-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 30px;
    }
    .waterfall-card {
      margin-top: 0;
    }
    .waterfall-card:nth-child(even) {
      margin-top: 40px;
    }

    .compare-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 20px;
    }
    .compare-highlight {
      border: 2px solid var(--accent-cyan);
    }

    .faq-item {
      background: rgba(255,255,255,0.03);
      border-radius: 8px;
      margin-bottom: 8px;
    }

    footer {
      background: #051020;
      border-top: 1px solid rgba(255,255,255,0.08);
      padding: 60px 0 30px;
    }

    @media (max-width: 1024px) {
      h1 { font-size: 36px; }
      .grid-3, .compare-grid { grid-template-columns: 1fr 1fr; }
      .waterfall-grid { grid-template-columns: 1fr; }
      .waterfall-card:nth-child(even) { margin-top: 0; }
    }
    @media (max-width: 640px) {
      .hero-grid { flex-direction: column; }
      .grid-3, .compare-grid { grid-template-columns: 1fr; }
      section { padding: 60px 0; }
    }