/* roulang page: index */
:root {
      --deep-bg: #060B1A;
      --midnight: #0A0E27;
      --cyan: #00F0FF;
      --hot-red: #FF4655;
      --text-primary: #FFFFFF;
      --text-body: #B0C4DE;
      --text-muted: #8899AA;
      --card-bg: rgba(255, 255, 255, 0.04);
      --card-border: rgba(0, 240, 255, 0.15);
      --card-hover-border: rgba(0, 240, 255, 0.4);
      --glass-blur: blur(16px);
      --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.05);
      --shadow-glow: 0 0 24px rgba(0, 240, 255, 0.15);
      --radius-lg: 16px;
      --radius-md: 12px;
      --radius-btn: 8px;
      --transition: all 0.3s ease;
      --font-mono: 'Rajdhani', 'Orbitron', sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      background-color: var(--deep-bg);
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', 'Inter', sans-serif;
      color: var(--text-body);
      line-height: 1.7;
      margin: 0;
      overflow-x: hidden;
    }
    h1, h2, h3, h4 {
      font-weight: 700;
      color: var(--text-primary);
    }
    a {
      color: var(--cyan);
      text-decoration: none;
      transition: var(--transition);
    }
    a:hover {
      color: var(--hot-red);
      text-decoration: underline;
    }
    .section-title {
      font-size: 2.25rem;
      margin-bottom: 2.5rem;
      position: relative;
      display: inline-block;
      letter-spacing: 1px;
    }
    .section-title::after {
      content: '';
      position: absolute;
      left: 0;
      bottom: -8px;
      width: 50px;
      height: 3px;
      background: var(--cyan);
      border-radius: 2px;
    }
    .glass-card {
      background: var(--card-bg);
      backdrop-filter: var(--glass-blur);
      -webkit-backdrop-filter: var(--glass-blur);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-lg);
      padding: 1.75rem 1.5rem;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .glass-card:hover {
      border-color: var(--card-hover-border);
      box-shadow: var(--shadow-glow), var(--shadow-card);
      transform: translateY(-4px);
    }
    .btn-primary-cyan {
      background: linear-gradient(135deg, #FF4655 0%, #FF6B7A 100%);
      border: none;
      color: white;
      font-weight: 700;
      padding: 0.875rem 2.25rem;
      border-radius: var(--radius-btn);
      letter-spacing: 1px;
      box-shadow: 0 4px 20px rgba(255, 70, 85, 0.4);
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }
    .btn-primary-cyan:hover {
      box-shadow: 0 6px 28px rgba(255, 70, 85, 0.6);
      transform: translateY(-2px);
      color: white;
    }
    .btn-outline-cyan {
      background: transparent;
      border: 1px solid rgba(0, 240, 255, 0.5);
      color: var(--cyan);
      border-radius: var(--radius-btn);
      padding: 0.75rem 1.75rem;
      font-weight: 600;
      transition: var(--transition);
    }
    .btn-outline-cyan:hover {
      background: rgba(0, 240, 255, 0.08);
      border-color: var(--cyan);
      color: var(--cyan);
    }
    .form-control {
      background: rgba(255, 255, 255, 0.05);
      border: 1px solid rgba(255, 255, 255, 0.1);
      border-radius: var(--radius-btn);
      color: white;
      padding: 0.75rem 1rem;
    }
    .form-control:focus {
      border-color: var(--cyan);
      box-shadow: 0 0 0 3px rgba(0, 240, 255, 0.1);
      background: rgba(255, 255, 255, 0.08);
      color: white;
    }
    /* 导航 */
    .navbar {
      background: rgba(6, 11, 26, 0.85);
      backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(0, 240, 255, 0.1);
      padding: 0.75rem 0;
    }
    .navbar-brand {
      font-weight: 700;
      font-size: 1.6rem;
      color: white !important;
      letter-spacing: 1px;
    }
    .nav-link {
      color: var(--text-body) !important;
      margin: 0 0.5rem;
      font-weight: 500;
      transition: 0.2s;
    }
    .nav-link:hover, .nav-link.active {
      color: var(--cyan) !important;
    }
    .mega-menu {
      position: relative;
    }
    .mega-panel {
      position: absolute;
      right: 0;
      top: 100%;
      background: rgba(10, 14, 39, 0.95);
      backdrop-filter: blur(24px);
      border: 1px solid rgba(0, 240, 255, 0.2);
      border-radius: 12px;
      padding: 1.5rem;
      min-width: 280px;
      box-shadow: 0 16px 48px rgba(0,0,0,0.6);
      opacity: 0;
      visibility: hidden;
      transform: translateY(10px);
      transition: 0.25s ease;
      z-index: 1050;
    }
    .mega-menu:hover .mega-panel {
      opacity: 1;
      visibility: visible;
      transform: translateY(0);
    }
    .hero-stat {
      font-family: var(--font-mono);
      font-size: 2.4rem;
      font-weight: 700;
      color: var(--cyan);
      text-shadow: 0 0 12px rgba(0,240,255,0.6);
    }
    .trend-up { color: #2ecc71; }
    .trend-down { color: #e74c3c; }
    .comparison-badge {
      background: rgba(0,240,255,0.12);
      color: var(--cyan);
      border-radius: 20px;
      padding: 0.2rem 1rem;
      font-size: 0.8rem;
    }
    footer {
      background: #040816;
      border-top: 1px solid rgba(0,240,255,0.08);
    }
    @media (max-width: 768px) {
      .hero-stat { font-size: 1.8rem; }
      .section-title { font-size: 1.8rem; }
    }