/* roulang page: index */
:root {
      --bg-deep: #0A0E17;
      --surface-glass: rgba(19, 26, 38, 0.65);
      --surface-card: #1C2433;
      --primary-cyan: #00E5FF;
      --accent-pink: #FF3366;
      --text-high: #F0F3FA;
      --text-muted: #8A94A6;
      --text-link: #B0BDF0;
      --border-glow: rgba(0, 229, 255, 0.15);
      --border-active: rgba(0, 229, 255, 0.35);
      --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);
      --radius-card: 16px;
      --radius-btn: 8px;
      --radius-tag: 4px;
      --font-title: 'Orbitron', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --font-body: 'Inter', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --transition: 0.25s ease;
    }

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

    body {
      background-color: var(--bg-deep);
      color: var(--text-high);
      font-family: var(--font-body);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }

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

    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition);
    }

    button, .btn {
      cursor: pointer;
      font-family: var(--font-body);
      border: none;
      background: transparent;
      transition: all var(--transition);
    }

    /* 导航栏 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: rgba(10, 14, 23, 0.85);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      z-index: 1000;
      border-bottom: 2px solid transparent;
      background-image: linear-gradient(rgba(10,14,23,0.85), rgba(10,14,23,0.85)), linear-gradient(90deg, var(--primary-cyan), var(--accent-pink));
      background-origin: border-box;
      background-clip: padding-box, border-box;
      border-bottom: 2px solid transparent;
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 100%;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-family: var(--font-title);
      font-weight: 800;
      font-size: 1.6rem;
      letter-spacing: 1px;
      color: var(--primary-cyan);
      text-shadow: 0 0 12px rgba(0,229,255,0.5);
    }
    .logo i {
      font-size: 2rem;
      color: var(--primary-cyan);
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      font-weight: 500;
      color: var(--text-link);
      font-size: 0.95rem;
      letter-spacing: 0.5px;
      position: relative;
      padding: 8px 0;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary-cyan);
      box-shadow: 0 0 10px var(--primary-cyan);
      transition: width var(--transition);
    }
    .nav-links a:hover {
      color: var(--primary-cyan);
    }
    .nav-links a:hover::after {
      width: 100%;
    }
    .nav-cta {
      background: var(--primary-cyan);
      color: var(--bg-deep);
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      font-size: 0.9rem;
      box-shadow: 0 0 18px rgba(0,229,255,0.4);
      letter-spacing: 0.5px;
    }
    .nav-cta:hover {
      box-shadow: 0 0 30px rgba(0,229,255,0.7);
      transform: scale(1.03);
      background: #33f0ff;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      background: transparent;
      border: none;
    }
    .hamburger span {
      width: 26px;
      height: 2px;
      background: var(--primary-cyan);
      box-shadow: 0 0 6px var(--primary-cyan);
      transition: 0.3s;
    }
    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: rgba(10,14,23,0.96);
        backdrop-filter: blur(25px);
        flex-direction: column;
        padding: 24px;
        gap: 24px;
        border-bottom: 2px solid var(--primary-cyan);
      }
      .nav-links.active {
        display: flex;
      }
      .hamburger {
        display: flex;
      }
    }

    /* 通用板块间距 */
    section {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 70px 0;
      }
    }

    /* Hero */
    .hero {
      min-height: 90vh;
      display: flex;
      align-items: center;
      position: relative;
      background: radial-gradient(ellipse at 70% 60%, rgba(0,229,255,0.08) 0%, transparent 50%), radial-gradient(ellipse at 30% 50%, rgba(255,51,102,0.06) 0%, transparent 60%), var(--bg-deep);
      overflow: hidden;
      padding-top: 72px;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
    }
    .hero-left h1 {
      font-family: var(--font-title);
      font-size: clamp(2.8rem, 6vw, 4rem);
      font-weight: 800;
      letter-spacing: 2px;
      line-height: 1.2;
      color: var(--text-high);
      margin-bottom: 24px;
    }
    .hero-left .sub {
      font-size: 1.2rem;
      color: var(--text-muted);
      margin-bottom: 36px;
    }
    .hero-btns {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary-cyan);
      color: var(--bg-deep);
      font-weight: 700;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      box-shadow: 0 0 20px rgba(0,229,255,0.45);
      font-size: 1rem;
    }
    .btn-primary:hover {
      box-shadow: 0 0 35px rgba(0,229,255,0.8);
      transform: scale(1.03);
    }
    .btn-secondary {
      background: transparent;
      border: 1px solid var(--primary-cyan);
      color: var(--primary-cyan);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
    }
    .btn-secondary:hover {
      background: rgba(0,229,255,0.1);
    }
    .hero-right img {
      border-radius: 24px;
      box-shadow: 0 0 40px rgba(0,229,255,0.25);
      border: 1px solid rgba(0,229,255,0.2);
    }
    @media (max-width: 768px) {
      .hero-grid {
        grid-template-columns: 1fr;
        text-align: center;
      }
      .hero-right {
        order: -1;
      }
      .hero-btns {
        justify-content: center;
      }
    }

    /* 卡片通用 */
    .glass-card {
      background: var(--surface-glass);
      backdrop-filter: blur(16px);
      border: 1px solid var(--border-glow);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      padding: 32px;
      transition: all 0.3s ease;
    }
    .glass-card:hover {
      border-color: var(--border-active);
      transform: translateY(-6px);
      box-shadow: 0 16px 40px rgba(0,0,0,0.6);
    }

    .section-title {
      font-family: var(--font-title);
      font-size: 2.5rem;
      font-weight: 700;
      margin-bottom: 16px;
      text-align: center;
    }
    .section-sub {
      color: var(--text-muted);
      text-align: center;
      max-width: 700px;
      margin: 0 auto 60px;
    }

    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    @media (max-width: 1024px) {
      .grid-3 { grid-template-columns: repeat(2, 1fr); }
    }
    @media (max-width: 520px) {
      .grid-3 { grid-template-columns: 1fr; }
    }

    .feature-icon {
      font-size: 2.8rem;
      color: var(--primary-cyan);
      margin-bottom: 20px;
    }

    .tag {
      display: inline-block;
      border: 1px solid var(--primary-cyan);
      color: var(--primary-cyan);
      padding: 4px 14px;
      border-radius: 20px;
      font-size: 0.8rem;
      letter-spacing: 0.5px;
    }

    .img-placeholder {
      background: rgba(0,229,255,0.08);
      border-radius: 10px;
      aspect-ratio: 16/9;
      overflow: hidden;
      margin-bottom: 20px;
    }

    .scenario-row {
      display: flex;
      align-items: center;
      gap: 40px;
      margin-bottom: 80px;
    }
    .scenario-row.reverse {
      flex-direction: row-reverse;
    }
    .scenario-img {
      flex: 1;
      border-radius: 20px;
      overflow: hidden;
      border: 1px solid var(--border-glow);
    }
    .scenario-text {
      flex: 1;
    }
    .num-watermark {
      font-family: var(--font-title);
      font-size: 5rem;
      font-weight: 900;
      color: rgba(0,229,255,0.15);
      line-height: 1;
    }
    @media (max-width: 768px) {
      .scenario-row, .scenario-row.reverse {
        flex-direction: column;
      }
    }

    .data-wall {
      display: flex;
      justify-content: space-around;
      flex-wrap: wrap;
      gap: 20px;
      margin-bottom: 60px;
    }
    .data-item {
      text-align: center;
    }
    .data-num {
      font-family: var(--font-title);
      font-size: 3rem;
      font-weight: 800;
      color: var(--primary-cyan);
      text-shadow: 0 0 15px var(--primary-cyan);
    }

    .faq-item {
      border-bottom: 1px solid rgba(0,229,255,0.2);
      padding: 24px 0;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 1.2rem;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-muted);
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      margin-top: 16px;
    }

    .cta-banner {
      background: radial-gradient(circle at center, rgba(255,51,102,0.15) 0%, transparent 70%);
      text-align: center;
      border-top: 1px solid var(--border-glow);
      border-bottom: 1px solid var(--border-glow);
    }
    .btn-pulse {
      background: var(--accent-pink);
      color: white;
      padding: 16px 40px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      box-shadow: 0 0 25px rgba(255,51,102,0.7);
      animation: pulse 2s infinite;
      font-size: 1.2rem;
    }
    @keyframes pulse {
      0% { box-shadow: 0 0 20px rgba(255,51,102,0.6); }
      50% { box-shadow: 0 0 45px rgba(255,51,102,0.9); }
      100% { box-shadow: 0 0 20px rgba(255,51,102,0.6); }
    }

    footer {
      background: #0A0E17;
      padding: 60px 0 30px;
      color: var(--text-muted);
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }
    .footer-logo {
      font-family: var(--font-title);
      color: var(--primary-cyan);
      font-size: 1.8rem;
    }