/* roulang page: index */
:root {
      --bg-deep: #0B0A0F;
      --bg-card: #1A1C29;
      --bg-section-alt: #0F0E17;
      --border-subtle: #2A2D3A;
      --text-body: #B0B3C1;
      --text-muted: #787B89;
      --text-white: #FFFFFF;
      --neon-cyan: #00F0B5;
      --neon-magenta: #D40078;
      --shadow-card: 0 8px 24px rgba(0,0,0,0.4);
      --shadow-glow: 0 0 18px rgba(0,240,181,0.3);
      --radius-card: 16px;
      --radius-btn: 10px;
      --font-mono: 'Rajdhani', 'Orbitron', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    }

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

    body {
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      background-color: var(--bg-deep);
      color: var(--text-body);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      scroll-behavior: smooth;
    }

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

    /* 卡片化导航面板 */
    .nav-panel {
      position: sticky;
      top: 16px;
      z-index: 100;
      background: rgba(26, 28, 41, 0.85);
      backdrop-filter: blur(14px);
      border: 1px solid var(--border-subtle);
      border-radius: 20px;
      margin: 16px auto 0;
      max-width: 1120px;
      padding: 12px 28px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      box-shadow: 0 10px 30px rgba(0,0,0,0.6);
    }

    .logo {
      font-size: 1.7rem;
      font-weight: 700;
      letter-spacing: -0.5px;
      background: linear-gradient(135deg, #00F0B5 0%, #00C48C 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      text-shadow: 0 0 10px rgba(0,240,181,0.4);
      font-family: var(--font-mono);
    }

    .nav-links {
      display: flex;
      gap: 8px;
      align-items: center;
      flex-wrap: wrap;
    }

    .nav-icon-btn {
      background: transparent;
      border: 1px solid transparent;
      color: var(--text-muted);
      border-radius: 14px;
      padding: 10px 14px;
      font-size: 0.9rem;
      font-weight: 500;
      display: flex;
      align-items: center;
      gap: 6px;
      transition: all 0.25s;
      white-space: nowrap;
      background: rgba(42,45,58,0.5);
    }

    .nav-icon-btn i {
      font-size: 1rem;
      color: var(--text-muted);
      transition: color 0.2s;
    }

    .nav-icon-btn:hover {
      background: rgba(0,240,181,0.08);
      border-color: var(--neon-cyan);
      color: var(--neon-cyan);
      transform: translateY(-2px);
      box-shadow: 0 0 12px rgba(0,240,181,0.25);
    }

    .nav-icon-btn:hover i {
      color: var(--neon-cyan);
    }

    .cta-btn-nav {
      background: var(--neon-cyan);
      color: #0B0A0F;
      font-weight: 700;
      padding: 12px 26px;
      border-radius: 30px;
      font-size: 0.95rem;
      letter-spacing: 0.5px;
      border: none;
      transition: all 0.3s;
      box-shadow: 0 4px 14px rgba(0,240,181,0.45);
      white-space: nowrap;
    }

    .cta-btn-nav:hover {
      background: #00FFC8;
      box-shadow: 0 6px 22px rgba(0,240,181,0.7);
      transform: scale(1.04);
      color: #0B0A0F;
    }

    /* Hero */
    #hero {
      min-height: 100vh;
      background: linear-gradient(135deg, rgba(11,10,15,0.88) 0%, rgba(11,10,15,0.45) 100%), url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      display: flex;
      align-items: center;
      justify-content: center;
      text-align: center;
      position: relative;
      border-bottom: 1px solid rgba(0,240,181,0.2);
    }

    .hero-content {
      max-width: 900px;
      padding: 0 20px;
    }

    h1 {
      font-size: 4.2rem;
      font-weight: 800;
      letter-spacing: -0.02em;
      color: #FFFFFF;
      text-shadow: 0 0 28px rgba(0,240,181,0.7);
      line-height: 1.2;
      margin-bottom: 20px;
      font-family: var(--font-mono);
    }

    .hero-sub {
      font-size: 1.4rem;
      color: #E0E0E0;
      margin-bottom: 36px;
      text-shadow: 0 0 8px rgba(0,0,0,0.6);
    }

    .btn-group {
      display: flex;
      gap: 20px;
      justify-content: center;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--neon-cyan);
      color: #0B0A0F;
      font-weight: 700;
      padding: 16px 38px;
      border-radius: var(--radius-btn);
      border: none;
      font-size: 1.1rem;
      letter-spacing: 0.8px;
      transition: 0.25s;
      box-shadow: 0 4px 18px rgba(0,240,181,0.5);
    }

    .btn-primary:hover {
      background: #00FFC8;
      box-shadow: 0 8px 28px rgba(0,240,181,0.75);
      transform: translateY(-3px);
      color: #0B0A0F;
    }

    .btn-outline {
      background: transparent;
      color: var(--neon-cyan);
      border: 2px solid var(--neon-cyan);
      padding: 16px 38px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: 0.25s;
    }

    .btn-outline:hover {
      background: rgba(0,240,181,0.08);
      box-shadow: 0 0 22px rgba(0,240,181,0.5);
    }

    section {
      padding: 100px 0;
    }

    h2 {
      font-size: 2.5rem;
      font-weight: 700;
      color: #FFFFFF;
      margin-bottom: 50px;
      position: relative;
      display: inline-block;
    }

    h2::after {
      content: '';
      position: absolute;
      left: 0;
      bottom: -12px;
      width: 70px;
      height: 4px;
      background: var(--neon-cyan);
      box-shadow: 0 0 12px var(--neon-cyan);
      border-radius: 4px;
    }

    .card {
      background: var(--bg-card);
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-card);
      padding: 30px;
      transition: all 0.3s ease;
      box-shadow: var(--shadow-card);
    }

    .card:hover {
      border-color: var(--neon-cyan);
      box-shadow: 0 12px 32px rgba(0,240,181,0.18);
      transform: translateY(-6px);
    }

    .grid-2x2 {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 28px;
    }

    .pain-icon {
      background: rgba(0,240,181,0.12);
      width: 56px;
      height: 56px;
      border-radius: 18px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--neon-cyan);
      font-size: 1.8rem;
      margin-bottom: 20px;
    }

    .solutions-grid {
      display: grid;
      grid-template-columns: 5fr 7fr;
      gap: 40px;
      align-items: start;
    }

    .solution-item {
      background: var(--bg-card);
      border-left: 4px solid var(--neon-cyan);
      padding: 24px;
      margin-bottom: 20px;
      border-radius: 0 12px 12px 0;
      transition: 0.25s;
    }

    .solution-item:hover {
      border-left-color: var(--neon-magenta);
      background: #1F212E;
    }

    .advantages-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 24px;
    }

    .big-card {
      background: linear-gradient(145deg, #1A1C29, #14151F);
      border: 1px solid var(--neon-cyan);
      box-shadow: 0 0 22px rgba(0,240,181,0.25);
    }

    .data-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 30px;
      text-align: center;
    }

    .stat-number {
      font-size: 3.2rem;
      font-weight: 800;
      color: var(--neon-cyan);
      text-shadow: 0 0 18px var(--neon-cyan);
      font-family: var(--font-mono);
    }

    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 28px;
    }

    .testimonial-card {
      border-left: 6px solid var(--neon-magenta);
      background: #181A26;
    }

    .accordion-item {
      border-bottom: 1px solid var(--border-subtle);
      padding: 18px 0;
    }

    .accordion-title {
      font-weight: 700;
      color: #fff;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .footer {
      background: #07060A;
      padding: 60px 0 30px;
    }

    @media (max-width: 1024px) {
      h1 { font-size: 3rem; }
      .solutions-grid { grid-template-columns: 1fr; }
      .advantages-grid { grid-template-columns: 1fr 1fr; }
    }

    @media (max-width: 768px) {
      .nav-panel { flex-wrap: wrap; gap: 12px; }
      .nav-links { overflow-x: auto; }
      h1 { font-size: 2.5rem; }
      .grid-2x2, .data-grid, .testimonial-grid { grid-template-columns: 1fr; }
      .advantages-grid { grid-template-columns: 1fr; }
    }