/* roulang page: index */
:root {
      --deep-space: #0A0E27;
      --dark-panel: #111836;
      --electric-cyan: #00F0FF;
      --energy-purple: #7B2FFF;
      --warm-gold: #FFB800;
      --text-light: #E0E8F0;
      --text-muted: #B0C4DE;
      --text-weak: #6B7B8D;
      --glass-bg: rgba(255, 255, 255, 0.03);
      --glass-border: rgba(255, 255, 255, 0.08);
      --glass-hover-border: rgba(0, 240, 255, 0.3);
      --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);
      --shadow-glow: 0 0 20px rgba(0, 240, 255, 0.5);
      --radius-card: 16px;
      --radius-btn: 50px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Inter", "SF Pro Display", system-ui, sans-serif;
      --transition: 0.3s ease;
    }

    * {
      box-sizing: border-box;
    }

    body {
      margin: 0;
      background-color: var(--deep-space);
      font-family: var(--font-sans);
      color: var(--text-muted);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

    h1, h2, h3, h4 {
      font-weight: 700;
      color: #FFFFFF;
      margin-top: 0;
    }

    h1 {
      font-size: clamp(2.5rem, 5vw, 4rem);
      line-height: 1.15;
      font-weight: 800;
      letter-spacing: -0.02em;
    }

    h2 {
      font-size: 2rem;
      font-weight: 700;
      margin-bottom: 1rem;
      position: relative;
      display: inline-block;
    }

    h2::after {
      content: '';
      display: block;
      width: 60px;
      height: 3px;
      background: var(--electric-cyan);
      margin-top: 0.5rem;
      border-radius: 2px;
    }

    .section-title-center h2::after {
      margin-left: auto;
      margin-right: auto;
    }

    h3 {
      font-size: 1.25rem;
      font-weight: 600;
      color: var(--electric-cyan);
    }

    .text-cyan {
      color: var(--electric-cyan);
    }

    .text-gold {
      color: var(--warm-gold);
    }

    .text-muted {
      color: var(--text-muted);
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    section {
      padding: clamp(60px, 10vh, 120px) 0;
    }

    /* 玻璃拟态卡片 */
    .glass-card {
      background: var(--glass-bg);
      backdrop-filter: blur(20px) saturate(180%);
      -webkit-backdrop-filter: blur(20px) saturate(180%);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card), inset 0 1px 0 rgba(255,255,255,0.05);
      transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
    }

    .glass-card:hover {
      transform: translateY(-8px);
      box-shadow: 0 16px 40px rgba(0,0,0,0.6), 0 0 30px rgba(0,240,255,0.15);
      border-color: var(--glass-hover-border);
    }

    /* 导航 */
    .glass-nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(10, 14, 39, 0.6);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border-bottom: 1px solid rgba(255,255,255,0.06);
      height: 70px;
      display: flex;
      align-items: center;
      transition: background 0.3s, border-color 0.3s, box-shadow 0.3s;
    }

    .glass-nav.scrolled {
      background: rgba(10, 14, 39, 0.95);
      border-bottom-color: rgba(255,255,255,0.12);
      box-shadow: 0 4px 20px rgba(0,0,0,0.5);
    }

    .nav-logo {
      font-size: 1.5rem;
      font-weight: 700;
      color: #FFFFFF;
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .nav-logo i {
      color: var(--electric-cyan);
      font-size: 1.8rem;
    }

    .nav-link {
      color: var(--text-muted);
      font-weight: 500;
      font-size: 0.95rem;
      margin-left: 32px;
      position: relative;
      transition: color 0.3s;
      text-decoration: none;
    }

    .nav-link:hover {
      color: var(--electric-cyan);
    }

    .nav-link::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 50%;
      transform: translateX(-50%) scaleX(0);
      width: 100%;
      height: 2px;
      background: var(--electric-cyan);
      transition: transform 0.3s;
    }

    .nav-link:hover::after {
      transform: translateX(-50%) scaleX(1);
    }

    .btn-glow {
      background: linear-gradient(135deg, var(--electric-cyan) 0%, var(--energy-purple) 100%);
      border: none;
      color: #FFFFFF;
      font-weight: 600;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      box-shadow: var(--shadow-glow), 0 4px 12px rgba(0,0,0,0.3);
      transition: all var(--transition);
      display: inline-block;
      text-align: center;
      cursor: pointer;
      font-size: 0.9rem;
      letter-spacing: 0.3px;
    }

    .btn-glow:hover {
      box-shadow: 0 0 35px rgba(0,240,255,0.8), 0 8px 20px rgba(0,0,0,0.4);
      transform: translateY(-2px);
      color: #fff;
      filter: brightness(1.1);
    }

    .btn-outline {
      background: transparent;
      border: 1px solid var(--electric-cyan);
      color: var(--electric-cyan);
      font-weight: 600;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      transition: all var(--transition);
      display: inline-block;
      text-align: center;
      cursor: pointer;
    }

    .btn-outline:hover {
      background: rgba(0,240,255,0.1);
      color: #fff;
      border-color: #fff;
    }

    /* Hero */
    .hero-bg {
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
    }

    .hero-overlay {
      background: radial-gradient(circle at 30% 40%, rgba(0,240,255,0.08) 0%, rgba(10,14,39,0.85) 80%);
      position: absolute;
      inset: 0;
    }

    /* 数字动画 */
    .stat-number {
      font-size: 3rem;
      font-weight: 800;
      color: var(--electric-cyan);
      line-height: 1.2;
    }

    /* FAQ 手风琴 */
    .accordion-item {
      background: rgba(255,255,255,0.02);
      border: 1px solid rgba(255,255,255,0.05);
      border-radius: 8px;
      margin-bottom: 12px;
    }

    .accordion-title {
      background: transparent;
      color: #FFFFFF;
      font-weight: 600;
      padding: 16px 20px;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      border: none;
      width: 100%;
      text-align: left;
    }

    .accordion-title i {
      color: var(--electric-cyan);
      transition: transform 0.3s;
    }

    .accordion-content {
      color: var(--text-muted);
      padding: 0 20px 16px;
      display: none;
    }

    .accordion-item.active .accordion-content {
      display: block;
    }

    .accordion-item.active {
      background: rgba(255,255,255,0.05);
      border-color: rgba(0,240,255,0.2);
    }

    .accordion-item.active .accordion-title i {
      transform: rotate(45deg);
    }

    footer {
      background: #060918;
      color: var(--text-weak);
    }

    @media (max-width: 640px) {
      .nav-links {
        display: none;
      }
      .mobile-menu-icon {
        display: block;
      }
    }