/* roulang page: index */
:root {
      --primary: #1E2A38;
      --accent: #C8A96E;
      --bg: #F8F7F4;
      --text: #2D3748;
      --text-light: #718096;
      --border: #E2E0DB;
      --white: #FFFFFF;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.04), 0 8px 24px rgba(0,0,0,0.04);
      --shadow-hover: 0 12px 32px rgba(0,0,0,0.08);
      --radius-lg: 12px;
      --radius-md: 8px;
      --transition: 0.3s ease;
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    body {
      font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", sans-serif;
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.7;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
    }
    .english-num {
      font-family: "Inter", "SF Pro Display", system-ui, sans-serif;
    }
    .container {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 24px;
      padding-right: 24px;
    }
    @media (max-width: 640px) {
      .container {
        padding-left: 16px;
        padding-right: 16px;
      }
    }
    /* 顶部信息条 */
    .top-bar {
      background-color: var(--primary);
      color: rgba(255,255,255,0.85);
      font-size: 13px;
      height: 38px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 24px;
    }
    /* 主导航 */
    .main-nav {
      background: var(--white);
      border-bottom: 1px solid var(--border);
      position: sticky;
      top: 0;
      z-index: 50;
      box-shadow: 0 1px 0 var(--border);
      transition: background 0.3s;
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo-text {
      font-size: 22px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: -0.3px;
      display: flex;
      align-items: center;
      gap: 8px;
      text-decoration: none;
    }
    .logo-diamond {
      width: 10px;
      height: 10px;
      background: var(--accent);
      transform: rotate(45deg);
      display: inline-block;
      margin-right: 4px;
      border-radius: 1px;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      text-decoration: none;
      color: var(--text);
      font-weight: 500;
      font-size: 16px;
      position: relative;
      padding-bottom: 6px;
      transition: color 0.2s;
    }
    .nav-links a:after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent);
      transition: width 0.3s;
    }
    .nav-links a:hover {
      color: var(--accent);
    }
    .nav-links a:hover:after {
      width: 100%;
    }
    .hamburger {
      display: none;
      font-size: 24px;
      background: none;
      border: none;
      color: var(--primary);
      cursor: pointer;
    }
    @media (max-width: 768px) {
      .nav-links {
        display: none;
      }
      .hamburger {
        display: block;
      }
      .mobile-menu {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: white;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 36px;
        z-index: 100;
        display: flex;
        transform: translateX(100%);
        transition: transform 0.4s ease;
      }
      .mobile-menu.open {
        transform: translateX(0);
      }
      .mobile-menu a {
        font-size: 20px;
        font-weight: 500;
        color: var(--primary);
      }
    }
    /* 按钮 */
    .btn-primary {
      background: var(--primary);
      color: white;
      border-radius: var(--radius-md);
      padding: 14px 32px;
      font-weight: 600;
      font-size: 15px;
      letter-spacing: 0.03em;
      border: none;
      cursor: pointer;
      transition: background 0.25s, box-shadow 0.25s;
      display: inline-block;
      text-decoration: none;
      text-align: center;
    }
    .btn-primary:hover {
      background: #141E2B;
      box-shadow: 0 4px 14px rgba(30,42,56,0.25);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      border-radius: var(--radius-md);
      padding: 14px 32px;
      font-weight: 600;
      font-size: 15px;
      letter-spacing: 0.03em;
      cursor: pointer;
      transition: 0.3s;
      text-decoration: none;
      display: inline-block;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }
    .btn-accent {
      background: var(--accent);
      color: var(--primary);
      border-radius: var(--radius-md);
      padding: 14px 32px;
      font-weight: 600;
      font-size: 15px;
      border: none;
      cursor: pointer;
      transition: background 0.25s;
      text-decoration: none;
      display: inline-block;
      letter-spacing: 0.03em;
    }
    .btn-accent:hover {
      background: #B8944F;
    }
    /* 卡片 */
    .card {
      background: var(--white);
      border-radius: var(--radius-lg);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      transition: transform 0.3s ease, box-shadow 0.3s ease;
      border: 1px solid var(--border);
    }
    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    /* 占位图风格 */
    .img-placeholder {
      background-color: #eae7e0;
      border-radius: var(--radius-md);
      width: 100%;
      height: auto;
      object-fit: cover;
    }
    /* 数据条 */
    .stats-bar {
      background: var(--primary);
      color: white;
      padding: 60px 0;
    }
    .stat-number {
      font-size: 42px;
      font-weight: 700;
      color: var(--accent);
      line-height: 1.2;
    }
    @media (max-width: 640px) {
      .stat-number {
        font-size: 32px;
      }
    }
    /* 手风琴 */
    .faq-item {
      border-bottom: 1px solid var(--border);
      padding: 20px 0;
      cursor: pointer;
    }
    .faq-question {
      font-weight: 600;
      font-size: 18px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--primary);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.3s;
      color: var(--text-light);
      padding-right: 40px;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 12px;
    }
    .faq-icon {
      transition: transform 0.3s;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }
    /* 其他 */
    .section-padding {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      .section-padding {
        padding: 64px 0;
      }
    }
    footer {
      background: var(--primary);
      color: rgba(255,255,255,0.7);
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1.5fr 1.8fr;
      gap: 40px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }
    .subscribe-input {
      background: rgba(255,255,255,0.1);
      border: 1px solid rgba(255,255,255,0.2);
      color: white;
      padding: 12px;
      border-radius: 6px;
      width: 100%;
    }