/* roulang page: index */
:root {
      --deep-space: #0A0E27;
      --electric-rose: #FF2D55;
      --cyber-cyan: #00F0FF;
      --text-primary: #FFFFFF;
      --text-secondary: rgba(255, 255, 255, 0.7);
      --card-bg: rgba(255, 255, 255, 0.03);
      --card-border: rgba(255, 45, 85, 0.2);
      --radius-md: 8px;
      --radius-sm: 6px;
      --shadow-glow: 0 0 20px rgba(255, 45, 85, 0.4);
      --spacing-section: 100px;
      --max-width: 1280px;
      --nav-height: 72px;
    }

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

    html {
      scroll-behavior: smooth;
    }

    body {
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      background-color: var(--deep-space);
      color: var(--text-primary);
      line-height: 1.8;
      font-weight: 400;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

    a {
      text-decoration: none;
      color: inherit;
    }

    button, input {
      font-family: inherit;
    }

    .container {
      max-width: var(--max-width);
      margin-left: auto;
      margin-right: auto;
      padding-left: 24px;
      padding-right: 24px;
    }

    /* Navigation */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(10, 14, 39, 0.85);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      display: flex;
      align-items: center;
      z-index: 1000;
      border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    }

    .nav-container {
      max-width: var(--max-width);
      width: 100%;
      margin: 0 auto;
      padding: 0 24px;
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .logo {
      font-size: 22px;
      font-weight: 800;
      color: #FFFFFF;
      letter-spacing: 1px;
      white-space: nowrap;
    }
    .logo span {
      color: var(--electric-rose);
    }

    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
      font-weight: 500;
      font-size: 15px;
      color: rgba(255, 255, 255, 0.8);
    }
    .nav-links a {
      transition: color 0.2s;
    }
    .nav-links a:hover {
      color: var(--cyber-cyan);
    }

    .nav-actions {
      display: flex;
      align-items: center;
      gap: 16px;
    }

    .search-icon {
      color: rgba(255, 255, 255, 0.8);
      font-size: 18px;
      cursor: pointer;
      transition: color 0.2s;
    }
    .search-icon:hover {
      color: var(--cyber-cyan);
    }

    .btn-primary {
      background: var(--electric-rose);
      color: #FFFFFF;
      font-weight: 600;
      padding: 10px 24px;
      border-radius: var(--radius-sm);
      border: none;
      cursor: pointer;
      transition: all 0.2s ease;
      display: inline-block;
      text-align: center;
      font-size: 15px;
      letter-spacing: 0.5px;
    }
    .btn-primary:hover {
      box-shadow: 0 0 18px rgba(255, 45, 85, 0.6);
      transform: scale(1.05);
    }

    .btn-outline {
      background: transparent;
      border: 1px solid var(--cyber-cyan);
      color: var(--cyber-cyan);
      font-weight: 600;
      padding: 10px 24px;
      border-radius: var(--radius-sm);
      cursor: pointer;
      transition: all 0.2s ease;
      display: inline-block;
      text-align: center;
      font-size: 15px;
    }
    .btn-outline:hover {
      background: rgba(0, 240, 255, 0.1);
    }

    .mobile-menu-btn {
      display: none;
      font-size: 24px;
      color: white;
      background: none;
      border: none;
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      justify-content: center;
      text-align: center;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
      margin-top: 0;
      padding-top: var(--nav-height);
    }
    .hero::after {
      content: '';
      position: absolute;
      inset: 0;
      background: radial-gradient(circle at 30% 40%, rgba(10,14,39,0.65) 0%, #0A0E27 95%);
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 900px;
      padding: 0 24px;
    }
    .hero h1 {
      font-size: 52px;
      font-weight: 800;
      line-height: 1.2;
      margin-bottom: 20px;
    }
    .hero .subtitle {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 40px;
      max-width: 700px;
      margin-left: auto;
      margin-right: auto;
    }
    .hero-buttons {
      display: flex;
      gap: 20px;
      justify-content: center;
      flex-wrap: wrap;
    }
    .scroll-hint {
      margin-top: 50px;
      font-size: 24px;
      color: rgba(255, 255, 255, 0.5);
      animation: bounce 2s infinite;
    }

    @keyframes bounce {
      0%, 20%, 50%, 80%, 100% { transform: translateY(0); }
      40% { transform: translateY(-12px); }
      60% { transform: translateY(-6px); }
    }

    /* Sections */
    section {
      padding: var(--spacing-section) 0;
    }

    .section-title {
      font-size: 38px;
      font-weight: 700;
      margin-bottom: 16px;
    }
    .section-desc {
      color: var(--text-secondary);
      font-size: 17px;
      margin-bottom: 48px;
      max-width: 700px;
    }

    .card {
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-md);
      padding: 28px;
      transition: all 0.25s ease;
      backdrop-filter: blur(4px);
    }
    .card:hover {
      border-color: var(--electric-rose);
      box-shadow: var(--shadow-glow);
    }

    /* Core values asymmetric */
    .values-grid {
      display: grid;
      grid-template-columns: 1fr 1fr 0.8fr;
      gap: 24px;
    }

    .tag {
      display: inline-block;
      border: 1px solid var(--cyber-cyan);
      color: var(--cyber-cyan);
      font-size: 13px;
      padding: 4px 12px;
      border-radius: 20px;
      margin-top: 12px;
    }

    /* Services tabs */
    .tab-nav {
      display: flex;
      gap: 12px;
      margin-bottom: 36px;
      flex-wrap: wrap;
    }
    .tab-btn {
      background: transparent;
      border: 1px solid rgba(255,255,255,0.2);
      color: white;
      padding: 10px 24px;
      border-radius: 20px;
      cursor: pointer;
      transition: 0.2s;
      font-weight: 500;
    }
    .tab-btn.active {
      background: var(--electric-rose);
      border-color: var(--electric-rose);
    }

    .split-layout {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
    }

    .team-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }

    .stat-wall {
      display: flex;
      gap: 40px;
      overflow-x: auto;
      padding-bottom: 20px;
      justify-content: center;
      flex-wrap: wrap;
    }
    .stat-item {
      text-align: center;
      flex: 0 0 auto;
    }
    .stat-number {
      font-size: 48px;
      font-weight: 800;
      color: var(--cyber-cyan);
    }

    .partner-grid {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 40px;
      align-items: center;
    }
    .partner-logo {
      filter: grayscale(100%);
      opacity: 0.6;
      transition: 0.3s;
      font-size: 28px;
      font-weight: bold;
      color: white;
    }
    .partner-logo:hover {
      filter: none;
      opacity: 1;
      color: var(--electric-rose);
    }

    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 20px;
    }
    .faq-item {
      border-bottom: 1px solid rgba(255,255,255,0.1);
      padding: 4px 0;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      padding: 16px 0;
      cursor: pointer;
      font-size: 17px;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.4s;
      color: var(--text-secondary);
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      padding-bottom: 16px;
    }

    .cta-banner {
      background: #060B1C;
      text-align: center;
      padding: 80px 24px;
    }

    footer {
      background: #060B1C;
      padding: 60px 24px 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
    }
    .footer-col h4 {
      color: var(--electric-rose);
      font-size: 14px;
      text-transform: uppercase;
      margin-bottom: 16px;
    }
    .footer-col a {
      display: block;
      color: rgba(255,255,255,0.6);
      margin-bottom: 8px;
      transition: 0.2s;
    }
    .footer-col a:hover {
      color: var(--cyber-cyan);
    }

    .copyright {
      text-align: center;
      margin-top: 48px;
      color: rgba(255,255,255,0.4);
      border-top: 1px solid rgba(255,255,255,0.08);
      padding-top: 24px;
    }

    @media (max-width: 1024px) {
      .values-grid { grid-template-columns: 1fr 1fr; }
      .split-layout { grid-template-columns: 1fr; }
      .team-grid { grid-template-columns: repeat(3, 1fr); }
      .footer-grid { grid-template-columns: repeat(2, 1fr); }
    }

    @media (max-width: 768px) {
      .nav-links, .nav-actions .btn-primary { display: none; }
      .mobile-menu-btn { display: block; }
      .hero h1 { font-size: 32px; }
      .section-title { font-size: 28px; }
      .values-grid { grid-template-columns: 1fr; }
      .team-grid { grid-template-columns: 1fr 1fr; }
      .faq-grid { grid-template-columns: 1fr; }
      .stat-wall { gap: 20px; }
    }