/* roulang page: index */
:root {
      --primary-deep: #0A0E17;
      --accent-cyan: #00F0FF;
      --accent-red: #FF4655;
      --bg-light: #F5F6FA;
      --card-white: #FFFFFF;
      --text-muted: #6B7280;
      --text-light: #B0B8C5;
      --border-light: #E8ECF1;
      --shadow-card: 0 4px 12px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.08);
      --radius-sm: 4px;
      --transition-smooth: 0.2s ease;
      --font-sans: 'Noto Sans SC', 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-light);
      color: #1F2937;
      line-height: 1.5;
      margin: 0;
      padding: 0;
      -webkit-font-smoothing: antialiased;
    }

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

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

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }

    /* 导航 */
    .site-header {
      background: var(--primary-deep);
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 40;
      box-shadow: 0 2px 8px rgba(0,0,0,0.2);
      transition: box-shadow 0.3s;
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
      height: 70px;
    }

    .logo {
      font-size: 22px;
      font-weight: 700;
      color: var(--accent-cyan);
      letter-spacing: 1px;
    }
    .logo span {
      color: white;
      font-weight: 400;
      margin-left: 4px;
      font-size: 0.9rem;
      color: #B0B8C5;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
    }

    .nav-links a {
      color: var(--text-light);
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
      padding: 8px 0;
      transition: color var(--transition-smooth);
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent-cyan);
    }

    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--accent-cyan);
    }

    .btn-cta-nav {
      background: var(--accent-red);
      color: white;
      padding: 10px 22px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 0.9rem;
      transition: background var(--transition-smooth);
      border: none;
      cursor: pointer;
    }
    .btn-cta-nav:hover {
      background: #E63946;
    }

    .menu-toggle {
      display: none;
      background: none;
      border: none;
      color: white;
      font-size: 1.8rem;
      cursor: pointer;
    }

    /* 移动端导航 */
    @media (max-width: 840px) {
      .nav-links {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        width: 100%;
        background: var(--primary-deep);
        flex-direction: column;
        padding: 20px;
        gap: 16px;
        box-shadow: 0 8px 20px rgba(0,0,0,0.3);
      }
      .nav-links.open {
        display: flex;
      }
      .menu-toggle {
        display: block;
      }
      .header-inner {
        height: 65px;
      }
    }

    /* Hero */
    .hero-section {
      background: var(--primary-deep);
      padding: 140px 0 80px;
      margin-top: 0;
      display: flex;
      align-items: center;
      position: relative;
    }

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

    .hero-left h1 {
      font-size: 3rem;
      font-weight: 700;
      color: white;
      margin-bottom: 20px;
      line-height: 1.2;
    }

    .hero-subtitle {
      color: var(--text-light);
      font-size: 1.2rem;
      margin-bottom: 30px;
    }

    .hero-stats {
      display: flex;
      gap: 30px;
      margin-bottom: 35px;
      flex-wrap: wrap;
    }

    .stat-item {
      display: flex;
      flex-direction: column;
    }
    .stat-number {
      font-size: 2rem;
      font-weight: 700;
      color: var(--accent-cyan);
    }
    .stat-label {
      color: #9CA3AF;
      font-size: 0.9rem;
    }

    .hero-actions {
      display: flex;
      gap: 18px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--accent-red);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      border: none;
      cursor: pointer;
      transition: background var(--transition-smooth);
    }
    .btn-primary:hover {
      background: #E63946;
    }

    .btn-outline {
      background: transparent;
      border: 1px solid white;
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      transition: all var(--transition-smooth);
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.1);
    }

    .hero-right {
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      min-height: 320px;
      border-radius: 0;
      position: relative;
      background-color: #1F2937;
    }
    .hero-right::after {
      content: '';
      position: absolute;
      top: 0; left: 0; right: 0; bottom: 0;
      background: rgba(10,14,23,0.35);
    }

    @media (max-width: 1024px) {
      .hero-grid {
        grid-template-columns: 1fr;
      }
      .hero-right {
        min-height: 260px;
        order: -1;
      }
      .hero-left h1 {
        font-size: 2.4rem;
      }
    }

    /* 通用板块 */
    .section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 2.25rem;
      font-weight: 700;
      margin-bottom: 24px;
      color: #0A0E17;
    }
    .section-desc {
      color: var(--text-muted);
      max-width: 700px;
      margin-bottom: 48px;
    }

    /* 核心优势卡片 */
    .advantages-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }
    .adv-card {
      background: var(--card-white);
      padding: 32px;
      border-radius: var(--radius-sm);
      border: 1px solid var(--border-light);
      box-shadow: var(--shadow-card);
      transition: all 0.25s ease;
    }
    .adv-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
      border-color: #d1d5db;
    }
    .adv-icon {
      font-size: 2.2rem;
      color: var(--accent-cyan);
      margin-bottom: 20px;
    }
    .adv-card h3 {
      font-size: 1.25rem;
      font-weight: 700;
      margin-bottom: 12px;
    }
    .adv-card p {
      color: var(--text-muted);
      font-size: 0.95rem;
      line-height: 1.6;
    }

    /* 数据看板 */
    .dark-board {
      background: var(--primary-deep);
      padding: 80px 0;
    }
    .data-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .data-card {
      background: rgba(255,255,255,0.05);
      padding: 28px 20px;
      border-radius: var(--radius-sm);
      text-align: center;
    }
    .data-number {
      font-size: 2.2rem;
      font-weight: 700;
      color: var(--accent-cyan);
    }
    .data-label {
      color: #E5E7EB;
      font-size: 0.9rem;
      margin: 8px 0 12px;
    }
    .progress-bar {
      height: 4px;
      background: rgba(255,255,255,0.2);
      width: 100%;
      border-radius: 2px;
    }
    .progress-fill {
      width: 90%;
      height: 100%;
      background: var(--accent-cyan);
    }

    /* 服务矩阵 */
    .service-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .service-card {
      background: white;
      border: 1px solid var(--border-light);
      padding: 28px;
      border-radius: var(--radius-sm);
      display: flex;
      flex-direction: column;
      transition: all 0.2s;
    }
    .service-card:hover {
      box-shadow: var(--shadow-hover);
    }
    .service-img {
      height: 140px;
      background-size: cover;
      background-position: center;
      margin-bottom: 18px;
      border-radius: 0;
    }
    .service-card h3 {
      font-size: 1.25rem;
      font-weight: 700;
    }
    .service-link {
      margin-top: 12px;
      color: var(--accent-cyan);
      font-weight: 600;
      display: flex;
      align-items: center;
      gap: 6px;
    }

    /* 对比 */
    .compare-row {
      display: grid;
      grid-template-columns: 1fr 60px 1fr;
      align-items: center;
      gap: 20px;
    }
    .vs-badge {
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--accent-red);
      text-align: center;
    }
    .compare-card {
      background: white;
      border: 1px solid var(--border-light);
      padding: 32px;
      border-radius: var(--radius-sm);
    }
    .compare-card.highlight {
      border: 2px solid var(--accent-cyan);
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      margin-bottom: 8px;
    }
    .faq-question {
      background: #F5F6FA;
      padding: 18px 20px;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .faq-answer {
      padding: 0 20px 20px;
      display: none;
      background: white;
    }
    .faq-answer.open {
      display: block;
    }

    /* CTA */
    .cta-red {
      background: var(--accent-red);
      padding: 80px 0;
      text-align: center;
    }
    .cta-white-title {
      color: white;
      font-size: 2.5rem;
    }
    .footer {
      background: var(--primary-deep);
      color: #B0B8C5;
      padding: 60px 0 30px;
    }

    @media (max-width: 768px) {
      .advantages-grid,
      .service-grid {
        grid-template-columns: 1fr;
      }
      .data-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .compare-row {
        grid-template-columns: 1fr;
      }
      .vs-badge {
        margin: 15px 0;
      }
      .section {
        padding: 60px 0;
      }
      .hero-section {
        padding: 120px 0 60px;
      }
    }