/* ============================================= */
/*  基础样式 & CSS变量 (可放入 base.css)          */
/* ============================================= */
        :root {
      --navy: #0a1628;
      --navy-light: #132038;
      --white: #ffffff;
      --gray-50: #f8f9fa;
      --gray-100: #f1f3f5;
      --gray-200: #e9ecef;
      --gray-400: #adb5bd;
      --gray-600: #6c757d;
      --gray-800: #343a40;
      --blue: #1a3a5c;
      --blue-hover: #142d4a;
      --gold: #c8944a;
      --gold-hover: #b3803a;
      --shadow: 0 1px 3px rgba(0,0,0,0.06);
      --shadow-lg: 0 4px 16px rgba(0,0,0,0.08);
      --radius: 6px;
      --transition: all 0.2s ease;
    }

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

    body {
      font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
      background: var(--white);
      color: var(--gray-800);
      line-height: 1.6;
    }

    .container { max-width: 1200px; margin: 0 auto; padding: 0 32px; }
    a { text-decoration: none; color: inherit; transition: var(--transition); }
    img { max-width: 100%; height: auto; display: block; }

    /* 头部 - 白色干净 */
    .site-header {
      background: var(--white);
      border-bottom: 1px solid var(--gray-200);
      position: sticky;
      top: 0;
      z-index: 100;
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 68px;
    }
    .logo {
      font-size: 1.5rem;
      font-weight: 700;
      color: var(--navy);
      letter-spacing: -0.3px;
    }
    .logo span { color: var(--gold); font-weight: 400; }
    .main-nav { display: flex; align-items: center; gap: 2rem; list-style: none; }
    .nav-item { position: relative; }
    .nav-link {
      font-size: 0.9rem;
      font-weight: 500;
      color: var(--gray-800);
      padding: 8px 0;
      letter-spacing: 0.2px;
    }
    .nav-link:hover,
    .nav-link.active { color: var(--gold); }
    .submenu {
      position: absolute;
      top: 100%;
      left: 0;
      background: var(--white);
      border: 1px solid var(--gray-200);
      border-radius: var(--radius);
      min-width: 160px;
      box-shadow: var(--shadow-lg);
      opacity: 0;
      visibility: hidden;
      transform: translateY(6px);
      transition: var(--transition);
      padding: 6px 0;
      list-style: none;
      z-index: 110;
    }
    .nav-item:hover .submenu { opacity: 1; visibility: visible; transform: translateY(0); }
    .submenu li a { display: block; padding: 10px 20px; font-size: 0.85rem; color: var(--gray-800); }
    .submenu li a:hover { background: var(--gray-50); color: var(--gold); }
    .lang-switch { display: flex; gap: 2px; margin-left: 1.5rem; }
    .lang-btn {
      background: none;
      border: none;
      padding: 6px 10px;
      font-size: 0.8rem;
      font-weight: 500;
      color: var(--gray-600);
      cursor: pointer;
    }
    .lang-btn.active { color: var(--navy); font-weight: 600; }
    .lang-btn:hover { color: var(--gold); }
    .mobile-btn { display: none; background: none; border: none; cursor: pointer; padding: 8px; }
    .mobile-btn span { display: block; width: 22px; height: 2px; background: var(--navy); margin: 4px 0; transition: var(--transition); }
    
    /* 页脚 */
    .site-footer {
      background: var(--navy);
      color: #8a9bb5;
      padding: 32px 0 20px;
      font-size: 0.85rem;
    }
    .footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 32px; align-items: start; }
    .footer-brand h3 { color: #fff; font-size: 1.1rem; margin-bottom: 8px; }
    .footer-brand h3 span { color: var(--gold); }
    .footer-brand p { margin-bottom: 4px; }
    .footer-links h4 { color: #fff; font-size: 0.9rem; margin-bottom: 10px; }
    .footer-links a { display: block; color: #8a9bb5; margin-bottom: 6px; font-size: 0.82rem; }
    .footer-links a:hover { color: var(--gold); }
    .footer-bottom { margin-top: 24px; padding-top: 16px; border-top: 1px solid rgba(255,255,255,0.06); text-align: center; font-size: 0.78rem; color: #6a7d95; }

    /* 关闭按钮 - 仅移动端显示 */
.nav-close {
  display: none;
  width: 100%;
  text-align: right;
  padding: 0 0 16px 0;
  border-bottom: 1px solid var(--gray-200);
}
.close-btn {
  background: none;
  border: none;
  cursor: pointer;
  color: var(--gray-600);
  padding: 6px;
  border-radius: var(--radius);
  transition: var(--transition);
}
.close-btn:hover {
  color: var(--navy);
  background: var(--gray-100);
}

@media (max-width: 1024px) {
  .nav-close { display: block; }
}

/* =============================================
   移动端（≤1024px）语言切换置于菜单底部
   紧贴"联系方式"下方，但不属于菜单框架
   ============================================= */
@media (max-width: 1024px) {

  /* 1. 隐藏顶部的语言切换 */
  .lang-switch {
    display: none !important;
  }

  /* 2. 当菜单展开时，语言切换固定在菜单底部 */
  .main-nav.active ~ .lang-switch {
    display: flex !important;
    position: fixed;
    bottom: 0;
    right: 0;
    width: 260px;                     /* 与菜单宽度一致 */
    background: var(--white);
    padding: 12px 16px 14px;
    border-top: 1px solid var(--gray-200);
    z-index: 102;                     /* 高于菜单（z-index:101） */
    justify-content: center;
    gap: 8px;
    box-shadow: 0 -2px 8px rgba(0, 0, 0, 0.05);
  }

  /* 3. 菜单底部预留空间，避免被语言切换遮挡 */
  .main-nav.active {
    padding-bottom: 72px;            /* 与语言切换高度匹配 */
  }

  /* 4. 语言切换按钮样式优化 */
  .lang-switch .lang-btn {
    font-size: 0.85rem;
    padding: 8px 20px;
    border-radius: 20px;
    background: transparent;
    color: var(--gray-600);
    font-weight: 500;
    border: none;
    cursor: pointer;
    transition: var(--transition);
    line-height: 1.4;
  }
  .lang-switch .lang-btn.active {
    background: var(--gray-100);
    color: var(--navy);
    font-weight: 600;
  }
  .lang-switch .lang-btn:hover {
    color: var(--gold);
  }

  /* 5. 小屏手机（≤480px）微调 */
  @media (max-width: 480px) {
    .main-nav.active ~ .lang-switch {
      /*width: 100%;                */
      /* 手机端撑满宽度，更易点击 */
      padding: 10px 14px 12px;
    }
    .main-nav.active {
      padding-bottom: 62px;
    }
    .lang-switch .lang-btn {
      font-size: 0.75rem;
      padding: 6px 16px;
    }
  }
}