/* roulang page: index */
:root {
      --primary: #0A1F3F;
      --accent-cyan: #00C9A7;
      --accent-gold: #F5A623;
      --bg-light: #F8FAFC;
      --card-white: #FFFFFF;
      --text-main: #1E293B;
      --text-muted: #64748B;
      --text-on-dark: #FFFFFF;
      --border-light: #E2E8F0;
      --radius-lg: 12px;
      --radius-md: 8px;
      --radius-sm: 6px;
      --shadow-card: 0 1px 3px rgba(10,31,63,0.06), 0 4px 12px rgba(10,31,63,0.04);
      --shadow-hover: 0 2px 8px rgba(10,31,63,0.1), 0 8px 24px rgba(10,31,63,0.08);
      --font-title: 'Inter', 'SF Pro Display', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --font-body: 'Inter', 'SF Pro Text', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --transition: 0.25s ease;
    }

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

    body {
      font-family: var(--font-body);
      background-color: var(--bg-light);
      color: var(--text-main);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }

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

    h1, h2, h3, h4 {
      font-family: var(--font-title);
      font-weight: 600;
    }

    h1 {
      font-size: 48px;
      line-height: 56px;
      font-weight: 700;
      letter-spacing: -0.5px;
    }

    h2 {
      font-size: 36px;
      line-height: 44px;
    }

    h3 {
      font-size: 24px;
      line-height: 32px;
    }

    h4 {
      font-size: 18px;
      line-height: 28px;
      font-weight: 500;
    }

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

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

    button, input, textarea {
      font-family: inherit;
    }

    /* 导航栏 - 卡片化控制面板 */
    .main-header {
      position: sticky;
      top: 16px;
      z-index: 50;
      padding: 0 16px;
    }

    .nav-panel {
      max-width: 1200px;
      margin: 0 auto;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(10px);
      border-radius: 16px;
      box-shadow: var(--shadow-card);
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 8px 24px;
      border: 1px solid var(--border-light);
      transition: all 0.3s ease;
    }

    .logo-area {
      display: flex;
      align-items: center;
      gap: 10px;
      font-size: 20px;
      font-weight: 600;
      color: var(--primary);
      font-family: var(--font-title);
    }

    .logo-icon {
      font-size: 28px;
      color: var(--accent-cyan);
    }

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

    .nav-item {
      display: flex;
      align-items: center;
      gap: 6px;
      padding: 8px 16px;
      border-radius: var(--radius-md);
      color: var(--text-main);
      font-weight: 500;
      background: transparent;
      transition: var(--transition);
    }

    .nav-item i {
      font-size: 16px;
      color: var(--accent-cyan);
    }

    .nav-item:hover {
      background: rgba(0, 201, 167, 0.08);
      color: var(--primary);
    }

    .btn-primary {
      background: var(--accent-cyan);
      color: white;
      border: none;
      padding: 12px 24px;
      border-radius: var(--radius-md);
      font-weight: 600;
      cursor: pointer;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      gap: 6px;
      white-space: nowrap;
    }

    .btn-primary:hover {
      background: #00B395;
      box-shadow: var(--shadow-hover);
      transform: translateY(-1px);
    }

    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      padding: 12px 24px;
      border-radius: var(--radius-md);
      font-weight: 600;
      cursor: pointer;
      transition: var(--transition);
    }

    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }

    .btn-gold {
      background: var(--accent-gold);
      color: white;
      border: none;
      padding: 16px 40px;
      border-radius: var(--radius-md);
      font-weight: 700;
      font-size: 16px;
      cursor: pointer;
      transition: var(--transition);
    }

    .btn-gold:hover {
      background: #E09510;
      box-shadow: var(--shadow-hover);
    }

    .mobile-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 24px;
      color: var(--primary);
    }

    /* Hero */
    .hero-section {
      padding: 80px 0 100px;
      background-color: var(--bg-light);
      position: relative;
      overflow: hidden;
    }

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

    .hero-left h1 {
      color: var(--primary);
      margin-bottom: 20px;
    }

    .hero-sub {
      font-size: 18px;
      color: var(--text-muted);
      margin-bottom: 32px;
    }

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

    .hero-right {
      display: flex;
      flex-direction: column;
      gap: 20px;
    }

    .metric-card {
      background: var(--card-white);
      border-radius: 10px;
      padding: 20px;
      box-shadow: var(--shadow-card);
      display: flex;
      align-items: center;
      gap: 16px;
      border-left: 4px solid var(--accent-cyan);
    }

    .metric-num {
      font-size: 36px;
      font-weight: 700;
      color: var(--accent-cyan);
      line-height: 1.1;
    }

    .metric-label {
      font-size: 14px;
      color: var(--text-muted);
    }

    .bg-decor {
      position: absolute;
      right: -80px;
      top: -40px;
      width: 500px;
      height: 500px;
      opacity: 0.08;
      pointer-events: none;
    }

    /* 板块通用 */
    .section {
      padding: 100px 0;
    }

    .section-title {
      text-align: center;
      margin-bottom: 48px;
      color: var(--primary);
    }

    /* 优势区 2+1错位 */
    .advantage-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
      max-width: 1000px;
      margin: 0 auto;
    }

    .adv-card {
      background: var(--card-white);
      border-radius: var(--radius-lg);
      padding: 32px;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    .adv-card.single {
      grid-column: span 2;
      max-width: 66%;
      margin: 0 auto;
    }

    .adv-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }

    .adv-icon {
      font-size: 36px;
      color: var(--accent-cyan);
    }

    .adv-card h3 {
      font-size: 22px;
    }

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

    /* 服务矩阵 */
    .service-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .service-card {
      background: var(--card-white);
      border-radius: var(--radius-lg);
      padding: 28px;
      box-shadow: var(--shadow-card);
      border: 1px solid transparent;
      transition: var(--transition);
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    .service-card:hover {
      border-color: var(--accent-cyan);
      box-shadow: var(--shadow-hover);
    }

    .service-icon {
      width: 48px;
      height: 48px;
      background: rgba(0,201,167,0.1);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--accent-cyan);
      font-size: 24px;
    }

    .link-arrow {
      color: var(--accent-cyan);
      font-weight: 500;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }

    /* 数据对比 */
    .dark-section {
      background: var(--primary);
      color: var(--text-on-dark);
    }

    .compare-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
    }

    .compare-left, .compare-right {
      background: rgba(255,255,255,0.05);
      border-radius: var(--radius-lg);
      padding: 32px;
    }

    .compare-right {
      border: 1px solid var(--accent-cyan);
    }

    .metric-row {
      display: flex;
      justify-content: space-between;
      margin: 20px 0;
    }

    .highlight {
      color: var(--accent-cyan);
      font-weight: 700;
    }

    .chart-placeholder {
      background: url('/assets/images/backpic/back-2.webp') center/cover no-repeat;
      height: 200px;
      border-radius: var(--radius-md);
      margin-top: 24px;
    }

    /* FAQ */
    .faq-container {
      max-width: 800px;
      margin: 0 auto;
    }

    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 16px 0;
      cursor: pointer;
    }

    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 18px;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-muted);
      padding-left: 24px;
      border-left: 3px solid transparent;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 12px;
      border-left-color: var(--accent-cyan);
    }

    /* CTA */
    .cta-section {
      background: var(--primary);
      padding: 80px 0;
      text-align: center;
    }

    .cta-form {
      display: flex;
      gap: 16px;
      max-width: 700px;
      margin: 32px auto 0;
      flex-wrap: wrap;
      justify-content: center;
    }

    .cta-form input {
      flex: 1 1 200px;
      padding: 14px 16px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-light);
      background: white;
    }

    /* 页脚 */
    .footer {
      background: var(--primary);
      color: #CBD5E1;
      padding: 60px 0 24px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    .social-icons i {
      font-size: 20px;
      margin-right: 16px;
      color: #94A3B8;
    }

    @media (max-width: 992px) {
      .hero-grid { grid-template-columns: 1fr; }
      .service-grid { grid-template-columns: repeat(2,1fr); }
      .compare-grid { grid-template-columns: 1fr; }
    }

    @media (max-width: 768px) {
      h1 { font-size: 36px; line-height: 44px; }
      .nav-menu { display: none; }
      .mobile-toggle { display: block; }
      .advantage-grid { grid-template-columns: 1fr; }
      .adv-card.single { grid-column: span 1; max-width: 100%; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }

    @media (max-width: 520px) {
      .service-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
    }