/* ========== CONTAINER ========== */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--s-4);
}

@media (min-width: 768px) {
  .container {
    padding-inline: var(--s-5);
  }
}

/* ========== GRID SYSTEM ========== */
.grid {
  display: grid;
  gap: var(--s-5);
}

/* Mobile: single column */
.grid-cols-1 {
  grid-template-columns: 1fr;
}

/* Tablet (>=640px) */
@media (min-width: 640px) {
  .sm\:grid-cols-2 {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* Desktop (>=1024px) */
@media (min-width: 1024px) {
  .lg\:grid-cols-2 {
    grid-template-columns: repeat(2, 1fr);
  }

  .lg\:grid-cols-3 {
    grid-template-columns: repeat(3, 1fr);
  }

  .lg\:grid-cols-4 {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* ========== FLEX UTILITIES ========== */
.flex {
  display: flex;
}

.flex-col {
  flex-direction: column;
}

.items-center {
  align-items: center;
}

.justify-between {
  justify-content: space-between;
}

.gap-2 {
  gap: var(--s-2);
}

.gap-3 {
  gap: var(--s-3);
}

.gap-4 {
  gap: var(--s-4);
}

.gap-5 {
  gap: var(--s-5);
}

/* ========== SIDEBAR LAYOUT ========== */
.layout-sidebar {
  display: grid;
  gap: var(--s-5);
}

@media (min-width: 1024px) {
  .layout-sidebar {
    grid-template-columns: 280px 1fr;
  }
}

/* ========== DOCUMENT LAYOUT (with TOC) ========== */
.layout-document {
  display: grid;
  gap: var(--s-5);
}

@media (min-width: 900px) {
  .layout-document {
    grid-template-columns: 240px 1fr;
  }

  .layout-document__toc {
    position: sticky;
    top: calc(var(--nav-height) + var(--s-5));
    max-height: calc(100vh - var(--nav-height) - var(--s-6));
    overflow-y: auto;
  }
}

/* ========== SPACING UTILITIES ========== */
.mt-0 {
  margin-top: 0;
}

.mt-2 {
  margin-top: var(--s-2);
}

.mt-4 {
  margin-top: var(--s-4);
}

.mt-5 {
  margin-top: var(--s-5);
}

.mt-6 {
  margin-top: var(--s-6);
}

.mb-0 {
  margin-bottom: 0;
}

.mb-2 {
  margin-bottom: var(--s-2);
}

.mb-4 {
  margin-bottom: var(--s-4);
}

.mb-5 {
  margin-bottom: var(--s-5);
}

.mb-6 {
  margin-bottom: var(--s-6);
}

.p-4 {
  padding: var(--s-4);
}

.p-5 {
  padding: var(--s-5);
}

/* ========== SECTION SPACING ========== */
.section {
  padding-block: var(--s-6);
}

@media (min-width: 768px) {
  .section {
    padding-block: var(--s-7);
  }
}