/* ========================================
   Layout — Vanguard Digital
   Breakpoints: mobile ≤640px · tablet ≤1024px · desktop default
   ======================================== */

/* Container */
.container {
  width: 100%;
  max-width: var(--w-default);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

.container-narrow {
  max-width: var(--w-narrow);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

.container-wide {
  max-width: var(--w-wide);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

/* Section spacing */
.section {
  padding-block: var(--space-section);
  position: relative;
}

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

.section-tight {
  padding-block: clamp(3rem, 2.5rem + 2vw, 5rem);
}

/* Stack utility (vertical rhythm) */
.stack > * + * { margin-top: var(--space-6); }
.stack-sm > * + * { margin-top: var(--space-4); }
.stack-lg > * + * { margin-top: var(--space-10); }

.flow {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.flow-sm {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.flow-wrap {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  flex-wrap: wrap;
}

/* Hairline divider */
.hairline {
  height: 1px;
  background: var(--color-hairline);
  border: 0;
  width: 100%;
}

.hairline-strong {
  height: 1px;
  background: var(--color-hairline-strong);
  border: 0;
  width: 100%;
}

/* Section dispatch mark — tiny № label + hairline rule */
.dispatch-mark {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: var(--space-6);
  margin-bottom: var(--space-10);
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-text-muted);
}

.dispatch-mark::before,
.dispatch-mark::after {
  content: '';
  height: 1px;
  background: var(--color-hairline);
}

.dispatch-mark-index {
  color: var(--color-accent);
}

/* Tablet */
@media (max-width: 1024px) {
  .container { padding-inline: var(--space-6); }
}

/* Mobile */
@media (max-width: 640px) {
  .container { padding-inline: var(--space-4); }
  .container-narrow { padding-inline: var(--space-4); }
  .container-wide { padding-inline: var(--space-4); }
}

/* Scroll margin for fixed navbar */
[id] { scroll-margin-top: 96px; }

/* Skip link */
.skip-link {
  position: fixed;
  top: -100px;
  left: var(--space-4);
  z-index: 500;
  padding: var(--space-2) var(--space-4);
  background: var(--color-accent);
  color: var(--color-text-invert);
  border-radius: var(--radius-sm);
  font-size: var(--fs-sm);
  font-weight: 600;
  transition: top 0.2s ease;
  text-decoration: none;
}

.skip-link:focus { top: var(--space-4); }

/* Visually hidden */
.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* Grid utilities */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-6);
}
.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-6);
}
.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-6);
}

@media (max-width: 1024px) {
  .grid-3 { grid-template-columns: 1fr; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
  .grid-2 { grid-template-columns: 1fr; }
  .grid-4 { grid-template-columns: 1fr; }
}