.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.section {
  padding: var(--space-section) 0;
}

.section-sm {
  padding: var(--space-2xl) 0;
}

/* Grid System */
.grid { display: grid; gap: var(--space-lg); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* Flex Utilities */
.flex { display: flex; }
.flex-center { display: flex; align-items: center; justify-content: center; }
.flex-between { display: flex; align-items: center; justify-content: space-between; }
.flex-gap { display: flex; gap: var(--space-md); }

/* Page Layout */
.page-with-sidebar {
  display: grid;
  grid-template-columns: var(--sidebar-width) 1fr;
  gap: var(--space-2xl);
  align-items: start;
}

/* Responsive */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(3, 1fr); }
  .page-with-sidebar { grid-template-columns: 1fr; }
  .sidebar { display: none; }
  .sidebar.open { display: block; }
}

@media (max-width: 768px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .grid-2 { grid-template-columns: 1fr; }
  :root { --space-section: 3rem; }
}

@media (max-width: 480px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: 1fr; }
  .container { padding: 0 var(--space-md); }
}