/**
 * Global layout: page shell, containers, header/footer regions, grids.
 */

body.is-nav-open {
  overflow: hidden;
}

.site {
  display: flex;
  flex-direction: column;
  min-height: 100dvh;
}

#site-shell-swappable,
[data-page-shell-swappable] {
  display: flex;
  flex-direction: column;
  flex: 1 0 auto;
  min-height: 0;
}

.site-main {
  flex: 1 0 auto;
}

.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--container-pad-x);
}

.container--narrow {
  max-width: var(--container-narrow);
}

.container--wide {
  max-width: var(--container-wide);
}

/* --- Sticky site header --- */
.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  height: var(--header-height);
  background-color: color-mix(in srgb, var(--color-bg) 92%, transparent);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition:
    height var(--duration-base) var(--ease-out),
    box-shadow var(--duration-base) var(--ease-out),
    border-color var(--duration-base) var(--ease-out),
    background-color var(--duration-base) var(--ease-out);
}

.site-header.is-scrolled {
  height: var(--header-height-scrolled);
  background-color: color-mix(in srgb, var(--color-bg) 96%, transparent);
  border-bottom-color: var(--color-border);
  box-shadow: var(--shadow-header);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
  height: 100%;
}

.site-header__brand {
  flex-shrink: 0;
}

.site-header__actions {
  display: flex;
  align-items: center;
  flex-wrap: nowrap;
  gap: var(--space-xs);
  flex-shrink: 0;
}

@media (min-width: 76rem) {
  .site-header > .container.site-header__inner {
    padding-inline: clamp(var(--space-lg), 5vw, 3.75rem);
  }

  .site-header__inner {
    display: grid;
    grid-template-columns: minmax(0, max-content) minmax(0, 1fr) auto;
    align-items: center;
    column-gap: clamp(var(--space-sm), 1.65vw, var(--space-lg));
  }

  .site-header__brand {
    grid-column: 1;
    margin-inline-end: clamp(0.875rem, 1.85vw, 1.625rem);
  }

  .nav-primary {
    grid-column: 2;
    justify-self: center;
    min-width: 0;
  }

  .site-header__actions {
    grid-column: 3;
    justify-self: end;
    gap: var(--space-sm);
    margin-inline-start: clamp(0.875rem, 1.85vw, 1.625rem);
  }
}

/* --- Footer --- */
.site-footer {
  background-color: var(--color-charcoal);
  color: var(--color-ivory-muted);
  padding-block: var(--space-3xl) var(--space-xl);
  margin-top: var(--space-4xl);
}

.site-footer a {
  color: var(--color-ivory);
  text-decoration: none;
}

.site-footer a:hover {
  color: var(--color-sand);
  text-decoration: underline;
  text-underline-offset: 0.18em;
}

.site-footer__grid {
  display: grid;
  gap: var(--space-xl);
}

@media (min-width: 48rem) {
  .site-footer__grid {
    grid-template-columns: 1.2fr repeat(2, 1fr);
    gap: var(--space-2xl);
  }
}

@media (min-width: 64rem) {
  .site-footer__grid {
    grid-template-columns: 1.4fr repeat(3, 1fr);
  }
}

.site-footer__heading {
  font-family: var(--font-display);
  font-size: var(--text-sm);
  letter-spacing: var(--tracking-caps);
  text-transform: uppercase;
  color: var(--color-sand);
  margin: 0 0 var(--space-sm);
}

.site-footer__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
  font-size: var(--text-sm);
}

.site-footer__meta {
  margin-top: var(--space-2xl);
  padding-top: var(--space-lg);
  border-top: 1px solid color-mix(in srgb, var(--color-ivory) 18%, transparent);
  font-size: var(--text-xs);
  color: var(--color-stone-light);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm) var(--space-lg);
  align-items: center;
  justify-content: space-between;
}

/* --- Simple content grids (page composition) --- */
.grid-2 {
  display: grid;
  gap: var(--space-lg);
}

@media (min-width: 48rem) {
  .grid-2 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: var(--space-xl);
  }
}

.grid-3 {
  display: grid;
  gap: var(--space-lg);
}

@media (min-width: 48rem) {
  .grid-3 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 64rem) {
  .grid-3 {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: var(--space-xl);
  }
}