/* Shared top navigation */
:root {
    --royal-blue: #4169E1;
    --royal-blue-dark: #2a4cb3;
    --text: #1a1a1a;
    --muted: #555555;
    --white: #ffffff;
    --sans: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --serif: Georgia, 'Times New Roman', serif;
  }

  .main-nav {
    padding: 16px 0;
    background: transparent;
    position: relative;
    z-index: 1000;
  }

  .main-nav .container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 32px;
    display: flex;
    justify-content: space-between;
    align-items: center;
  }

  .nav-brand {
    font-family: var(--serif);
    font-size: 1.3rem;
    font-weight: 800;
    color: var(--text);
    text-decoration: none;
    transition: color 0.2s ease;
  }

  .nav-brand:hover {
    color: var(--royal-blue);
  }

  .nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
    list-style: none;
    margin: 0;
    padding: 0;
  }

  .nav-link {
    font-family: var(--sans);
    font-size: 1rem;
    color: var(--text);
    text-decoration: none;
    transition: color 0.2s ease;
  }

  .nav-link:hover {
    color: var(--royal-blue);
  }

  .nav-link.active {
    color: var(--royal-blue);
    font-weight: 600;
  }

  .hamburger {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    z-index: 1001;
  }

  .hamburger span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text);
    margin: 5px 0;
    transition: 0.3s;
  }

  .mobile-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: var(--white);
    z-index: 999;
    flex-direction: column;
    justify-content: flex-start;
    padding-top: 100px;
    padding-right: 40px;
    opacity: 0;
    transition: opacity 0.3s ease;
  }

  .mobile-overlay.open {
    display: flex;
    opacity: 1;
  }

  .mobile-overlay ul {
    list-style: none;
    margin: 0;
    padding: 0;
    text-align: right;
  }

  .mobile-overlay li {
    border-top: 1px solid #e4e9f5;
  }

  .mobile-overlay a {
    display: block;
    padding: 20px 0;
    font-size: 1.5rem;
    font-family: var(--sans);
    color: var(--text);
    text-decoration: none;
    transition: color 0.2s ease;
  }

  .mobile-overlay a:hover,
  .mobile-overlay a.active {
    color: var(--royal-blue);
  }

  @media (max-width: 768px) {
    .main-nav .container {
      padding: 0 20px;
    }

    .hamburger {
      display: block;
    }

    .nav-links {
      display: none;
    }
  }