@media (max-width: 768px) {
  .sidebar {
    position: fixed;
    transform: translateX(-100%);
    transition: transform 0.3s ease;
    width: 280px;
  }

  .sidebar.open {
    transform: translateX(0);
  }

  .main-content {
    margin-left: 0;
    padding: var(--space-4);
  }

  .mobile-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-4);
    background: var(--color-dark-blue);
    color: var(--color-white);
    margin: calc(-1 * var(--space-4));
    margin-bottom: var(--space-6);
  }

  .mobile-header h1 {
    font-size: var(--text-lg);
    font-weight: var(--weight-bold);
    letter-spacing: 0.05em;
  }

  .menu-toggle {
    background: none;
    border: none;
    color: var(--color-white);
    font-size: var(--text-xl);
    cursor: pointer;
    padding: var(--space-2);
  }

  .sidebar-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.5);
    z-index: 99;
    display: none;
  }

  .sidebar-overlay.open {
    display: block;
  }

  .grid-2, .grid-3, .grid-4 {
    grid-template-columns: 1fr;
  }

  .page-header {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-4);
  }

  .filter-bar {
    flex-direction: column;
  }

  .filter-bar .form-control,
  .filter-bar input[type="search"] {
    width: 100%;
    min-width: 0;
  }

  .form-row {
    grid-template-columns: 1fr;
  }

  .modal {
    width: 95%;
    padding: var(--space-6);
  }
}

@media (min-width: 769px) {
  .mobile-header {
    display: none;
  }

  .menu-toggle {
    display: none;
  }

  .sidebar-overlay {
    display: none !important;
  }
}

@media (max-width: 480px) {
  html {
    font-size: 14px;
  }

  .stat-card .stat-value {
    font-size: var(--text-2xl);
  }
}