/* roulang page: index */
/* 设计变量与基础重置 */
    :root {
      --deep-green: #0B1A1A;
      --warm-gold: #C49A6C;
      --soft-white: #F7F4F0;
      --card-bg: #FDFBF7;
      --text-primary: #1E2B2B;
      --text-secondary: #5A6A6A;
      --text-muted: #8A9696;
      --shadow-sm: 0 2px 20px rgba(0,0,0,0.03);
      --shadow-md: 0 8px 40px rgba(0,0,0,0.06);
      --radius-md: 8px;
      --radius-lg: 12px;
    }
    * {
      box-sizing: border-box;
    }
    body {
      margin: 0;
      font-family: 'Inter', 'PingFang SC', system-ui, sans-serif;
      background-color: var(--soft-white);
      color: var(--text-primary);
      line-height: 1.7;
      display: flex;
      min-height: 100vh;
    }
    /* 左侧导航 App Shell */
    .app-nav {
      width: 88px;
      background-color: var(--deep-green);
      position: fixed;
      top: 0;
      left: 0;
      height: 100vh;
      display: flex;
      flex-direction: column;
      align-items: center;
      padding: 2rem 0;
      z-index: 50;
      box-shadow: 2px 0 15px rgba(0,0,0,0.08);
      transition: width 0.3s ease;
    }
    .nav-logo {
      font-family: 'Noto Serif SC', 'Songti SC', serif;
      color: var(--warm-gold);
      font-weight: 600;
      font-size: 1.25rem;
      writing-mode: vertical-rl;
      text-orientation: mixed;
      letter-spacing: 4px;
      margin-bottom: 2.5rem;
      line-height: 1.4;
    }
    .nav-links {
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 2rem;
      flex: 1;
    }
    .nav-item {
      color: #8A9696;
      text-decoration: none;
      font-size: 0.8rem;
      writing-mode: vertical-rl;
      text-orientation: mixed;
      font-weight: 500;
      letter-spacing: 2px;
      transition: color 0.2s, border-color 0.2s;
      border-left: 2px solid transparent;
      padding-left: 8px;
      padding-right: 4px;
    }
    .nav-item:hover {
      color: var(--warm-gold);
      border-left-color: var(--warm-gold);
    }
    .nav-footer {
      margin-top: auto;
      color: #5A6A6A;
      font-size: 0.7rem;
      writing-mode: vertical-rl;
      text-orientation: mixed;
      opacity: 0.7;
    }
    /* 主内容区域 */
    .main-content {
      margin-left: 88px;
      flex: 1;
      width: calc(100% - 88px);
      background-color: var(--soft-white);
    }
    /* 移动端顶部导航 */
    .mobile-header {
      display: none;
      background-color: var(--deep-green);
      color: white;
      padding: 1rem 1.5rem;
      align-items: center;
      justify-content: space-between;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 60;
    }
    .hamburger {
      display: flex;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--warm-gold);
      border-radius: 2px;
    }
    .mobile-drawer {
      position: fixed;
      top: 0;
      left: -100%;
      width: 80%;
      max-width: 300px;
      height: 100vh;
      background: var(--deep-green);
      z-index: 70;
      transition: left 0.3s ease;
      display: flex;
      flex-direction: column;
      padding: 2rem;
    }
    .mobile-drawer.open {
      left: 0;
    }
    .drawer-links {
      display: flex;
      flex-direction: column;
      gap: 2rem;
      margin-top: 3rem;
    }
    .drawer-link {
      color: #ccc;
      text-decoration: none;
      font-size: 1.2rem;
      border-left: 2px solid transparent;
      padding-left: 12px;
    }
    .drawer-link:hover {
      color: var(--warm-gold);
      border-left-color: var(--warm-gold);
    }
    /* 容器与排版 */
    .container-custom {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 2rem;
    }
    section {
      padding: 5rem 0;
    }
    h2 {
      font-family: 'Noto Serif SC', 'Songti SC', serif;
      font-size: 2.25rem;
      font-weight: 600;
      color: var(--text-primary);
      margin-bottom: 1.5rem;
    }
    .gold-line {
      width: 60px;
      height: 3px;
      background: var(--warm-gold);
      margin: 1rem 0 2rem;
    }
    /* 卡片与悬停 */
    .card-elevated {
      background: #fff;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
      transition: box-shadow 0.3s, border-top 0.2s;
      border-top: 3px solid transparent;
    }
    .card-elevated:hover {
      box-shadow: var(--shadow-md);
      border-top-color: var(--warm-gold);
    }
    /* 按钮 */
    .btn-primary {
      background: var(--warm-gold);
      color: white;
      padding: 0.9rem 2.2rem;
      border-radius: 6px;
      font-weight: 500;
      letter-spacing: 0.5px;
      transition: background 0.2s, transform 0.1s;
      display: inline-block;
      text-decoration: none;
    }
    .btn-primary:hover {
      background: #b0814f;
      transform: translateY(-1px);
    }
    .btn-outline {
      border: 1.5px solid var(--warm-gold);
      color: var(--warm-gold);
      padding: 0.9rem 2.2rem;
      border-radius: 6px;
      background: transparent;
      transition: background 0.2s, color 0.2s;
      text-decoration: none;
      display: inline-block;
    }
    .btn-outline:hover {
      background: rgba(196,154,108,0.1);
      color: #b0814f;
    }
    /* FAQ 折叠 */
    .faq-item {
      border-bottom: 1px solid #e0dbd4;
      padding: 1.5rem 0;
    }
    .faq-question {
      font-size: 1.1rem;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      align-items: center;
      gap: 12px;
      color: var(--text-primary);
    }
    .faq-dot {
      width: 8px;
      height: 8px;
      background: var(--warm-gold);
      border-radius: 50%;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-secondary);
      padding-left: 28px;
      margin-top: 0.5rem;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
    }
    /* 横向滚动证言 */
    .testimonial-scroll {
      display: flex;
      gap: 1.5rem;
      overflow-x: auto;
      padding-bottom: 1rem;
      scroll-snap-type: x mandatory;
    }
    .testimonial-card {
      min-width: 300px;
      background: var(--card-bg);
      border-radius: var(--radius-lg);
      padding: 2rem;
      border-left: 4px solid var(--warm-gold);
      scroll-snap-align: start;
    }
    /* 响应式 */
    @media (max-width: 768px) {
      .app-nav {
        display: none;
      }
      .mobile-header {
        display: flex;
      }
      .main-content {
        margin-left: 0;
        width: 100%;
        padding-top: 70px;
      }
      h2 {
        font-size: 1.8rem;
      }
      section {
        padding: 3rem 1.2rem;
      }
      .container-custom {
        padding: 0 1.2rem;
      }
    }
    /* 动画 */
    .fade-up {
      opacity: 0;
      transform: translateY(20px);
      transition: opacity 0.7s, transform 0.7s;
    }
    .fade-up.visible {
      opacity: 1;
      transform: translateY(0);
    }