/* roulang page: index */
:root {
      --brand-deep: #1A3B5C;
      --brand-darker: #0F2238;
      --brand-gold: #C9A96E;
      --brand-softgold: #F5EFE6;
      --surface: #F8FAFC;
      --card: #FFFFFF;
      --body: #334155;
      --muted: #64748B;
      --border: #E2E8F0;
      --shadow-card: 0px 4px 24px rgba(0,0,0,0.04);
      --shadow-card-hover: 0px 8px 32px rgba(0,0,0,0.08);
      --max-width: 1280px;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: 'Inter', system-ui, -apple-system, 'PingFang SC', 'Microsoft YaHei', sans-serif;
      color: var(--body);
      background-color: var(--surface);
      line-height: 1.7;
      margin: 0;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      display: block;
    }
    a, button, input {
      outline: none;
    }
    /* 自定义滚动条（浅色） */
    ::-webkit-scrollbar {
      width: 6px;
    }
    ::-webkit-scrollbar-track {
      background: #f1f5f9;
    }
    ::-webkit-scrollbar-thumb {
      background: #cbd5e1;
      border-radius: 12px;
    }
    /* 左侧导航固定布局（桌面端） */
    .main-layout {
      display: flex;
      min-height: 100vh;
    }
    .left-nav {
      width: 280px;
      flex-shrink: 0;
      background: #FFFFFF;
      border-right: 1px solid var(--border);
      display: flex;
      flex-direction: column;
      height: 100vh;
      position: fixed;
      left: 0;
      top: 0;
      z-index: 40;
      padding: 2rem 1.5rem;
    }
    .right-content {
      margin-left: 280px;
      width: 100%;
      background: var(--surface);
    }
    .nav-logo {
      font-weight: 700;
      font-size: 1.75rem;
      color: var(--brand-deep);
      letter-spacing: -0.5px;
      margin-bottom: 2.5rem;
    }
    .nav-logo span {
      color: var(--brand-gold);
    }
    .nav-links {
      display: flex;
      flex-direction: column;
      gap: 0.5rem;
      flex: 1;
    }
    .nav-link {
      display: block;
      padding: 0.7rem 1rem;
      border-radius: 8px;
      color: var(--body);
      font-weight: 500;
      text-decoration: none;
      transition: all 0.2s ease;
      position: relative;
      border-left: 3px solid transparent;
    }
    .nav-link:hover {
      background: #f8fafc;
      color: var(--brand-deep);
      border-left-color: var(--brand-gold);
    }
    .nav-link.active {
      color: var(--brand-deep);
      font-weight: 600;
      background: rgba(26,59,92,0.04);
      border-left-color: var(--brand-gold);
    }
    /* 移动端顶部导航 */
    .mobile-header {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: white;
      height: 64px;
      align-items: center;
      justify-content: space-between;
      padding: 0 1.5rem;
      z-index: 50;
      border-bottom: 1px solid var(--border);
    }
    .mobile-drawer {
      position: fixed;
      top: 64px;
      left: 0;
      width: 100%;
      background: white;
      transform: translateY(-120%);
      transition: transform 0.3s ease;
      z-index: 45;
      padding: 1rem 1.5rem;
      box-shadow: 0 10px 20px rgba(0,0,0,0.05);
      display: flex;
      flex-direction: column;
      gap: 0.5rem;
    }
    .mobile-drawer.open {
      transform: translateY(0);
    }
    /* Hero 区域 */
    .hero-section {
      display: flex;
      align-items: center;
      min-height: 100vh;
      padding: 2rem 4rem;
      background: white;
    }
    .hero-text {
      flex: 1;
      padding-right: 2rem;
    }
    .hero-image {
      flex: 1;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      border-radius: 24px;
      min-height: 480px;
      box-shadow: 0 20px 35px rgba(0,0,0,0.06);
    }
    /* 卡片通用 */
    .card-hover {
      transition: all 0.3s ease-out;
    }
    .card-hover:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card-hover);
    }
    /* 手风琴 */
    .faq-item {
      border-bottom: 1px solid var(--border);
    }
    .faq-question {
      padding: 1.25rem 0;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      font-weight: 500;
      color: #1E293B;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: #475569;
      line-height: 1.7;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 1.25rem;
    }
    .faq-item.active .faq-question {
      color: var(--brand-deep);
    }
    /* 响应式 */
    @media (max-width: 1024px) {
      .left-nav {
        display: none;
      }
      .mobile-header {
        display: flex;
      }
      .right-content {
        margin-left: 0;
        padding-top: 64px;
      }
      .hero-section {
        flex-direction: column;
        padding: 2rem 1.5rem;
        min-height: auto;
      }
      .hero-text {
        padding-right: 0;
        margin-bottom: 2rem;
      }
      .hero-image {
        min-height: 300px;
        width: 100%;
      }
    }
    @media (max-width: 640px) {
      .hero-section {
        padding: 1.5rem 1rem;
      }
    }