/* ==========================================================================
   Site header: brand, primary navigation, actions, mobile nav.
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--color-background);
  box-shadow: 0 1px 0 var(--color-border);
}

/* --- Main row --------------------------------------------------------------- */
.site-header__inner {
  display: grid;
  grid-template-columns: 1fr auto;
  grid-template-areas: "brand actions";
  align-items: center;
  gap: var(--space-4);
  min-height: var(--header-height);
  padding-block: var(--space-2);
}

.site-header__brand { grid-area: brand; }
.site-header__actions {
  grid-area: actions;
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.site-header__actions .site-header__cta {
  display: none;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--color-text);
}

.brand__mark {
  width: 3rem;
  height: 3rem;
  transition: width var(--transition-base), height var(--transition-base);
}

.brand__logo {
  height: 3rem;
  width: auto;
}

.brand__wordmark {
  font-size: var(--text-lg);
  font-weight: var(--font-weight-bold);
  letter-spacing: -0.01em;
  color: var(--color-navy);
  white-space: nowrap;
}

.icon-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0;
  border: 0;
  border-radius: var(--radius-md);
  background: transparent;
  color: var(--color-navy);
}

.icon-button:hover {
  background: var(--color-surface);
  color: var(--color-primary);
}

.icon-button .icon {
  width: 1.5rem;
  height: 1.5rem;
}

/* Hamburger shows "open" icon by default, "close" when expanded */
.site-header__menu-toggle .icon--close { display: none; }
.site-header__menu-toggle[aria-expanded="true"] .icon--open { display: none; }
.site-header__menu-toggle[aria-expanded="true"] .icon--close { display: block; }

/* Very narrow screens: let the wordmark wrap so it never collides with the actions */
@media (max-width: 25em) {
  .site-header__brand {
    min-width: 0;
  }

  .site-header .brand__wordmark {
    white-space: normal;
    max-width: 7.5rem;
    font-size: var(--text-sm);
    line-height: 1.15;
  }
}

/* --- Primary navigation (desktop) ------------------------------------------- */
.primary-nav {
  display: none;
  grid-area: nav;
}

.primary-nav__list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin: 0;
  padding: 0;
  list-style: none;
}

.primary-nav__item {
  position: relative;
  display: flex;
  align-items: center;
}

.primary-nav__link {
  display: inline-flex;
  align-items: center;
  gap: 0.3em;
  padding: var(--space-3) var(--space-3);
  font-weight: var(--font-weight-bold);
  font-size: var(--text-md);
  color: var(--color-text);
  text-decoration: none;
  border-bottom: 3px solid transparent;
}

.primary-nav__link:hover,
.primary-nav__item.is-current > .primary-nav__link,
.primary-nav__item.is-ancestor > .primary-nav__link {
  color: var(--color-primary);
  border-bottom-color: var(--color-accent);
}

.primary-nav__toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.75rem;
  height: 1.75rem;
  margin-left: -0.5rem;
  padding: 0;
  border: 0;
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--color-muted);
}

.primary-nav__toggle .icon {
  width: 1rem;
  height: 1rem;
  transition: transform var(--transition-fast);
}

.primary-nav__toggle[aria-expanded="true"] .icon {
  transform: rotate(180deg);
}

.primary-nav__submenu {
  position: absolute;
  top: 100%;
  left: 0;
  z-index: 20;
  min-width: 15rem;
  margin: 0;
  padding: var(--space-2) 0;
  list-style: none;
  background: var(--color-surface);
  border-top: 3px solid var(--color-accent);
  border-radius: 0 0 var(--radius-md) var(--radius-md);
  box-shadow: var(--shadow-md);
  opacity: 0;
  visibility: hidden;
  transform: translateY(0.25rem);
  transition: opacity var(--transition-fast), transform var(--transition-fast), visibility 0s linear var(--transition-fast);
}

.primary-nav__item.is-open > .primary-nav__submenu,
.primary-nav__item:hover > .primary-nav__submenu,
.primary-nav__item:focus-within > .primary-nav__submenu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
  transition-delay: 0s;
}

.primary-nav__sublink {
  display: block;
  padding: var(--space-2) var(--space-4);
  color: var(--color-text);
  text-decoration: none;
}

.primary-nav__sublink:hover,
.primary-nav__subitem.is-current > .primary-nav__sublink {
  background: var(--color-background);
  color: var(--color-primary);
}

/* --- Mobile navigation (off-canvas) ----------------------------------------- */
.mobile-nav {
  position: fixed;
  inset: var(--header-height) 0 0 0;
  z-index: 90;
  background: var(--color-navy);
  color: var(--color-text-inverse);
  overflow: hidden;
}

.mobile-nav__scroll {
  height: 100%;
  overflow-y: auto;
  padding: var(--space-5) var(--container-padding) var(--space-8);
}

.mobile-nav__list,
.mobile-nav__submenu {
  margin: 0;
  padding: 0;
  list-style: none;
}

.mobile-nav__item + .mobile-nav__item {
  border-top: 1px solid rgb(255 255 255 / 0.15);
}

.mobile-nav__row {
  display: flex;
  align-items: center;
}

.mobile-nav__link {
  display: flex;
  align-items: center;
  gap: 0.4em;
  flex: 1 1 auto;
  padding: var(--space-4) 0;
  font-size: var(--text-lg);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-inverse);
  text-decoration: none;
}

.mobile-nav__item.is-current > .mobile-nav__link,
.mobile-nav__item.is-current > .mobile-nav__row > .mobile-nav__link {
  color: var(--color-accent);
}

.mobile-nav__toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.75rem;
  height: 2.75rem;
  border: 0;
  border-radius: var(--radius-md);
  background: transparent;
  color: var(--color-text-inverse);
}

.mobile-nav__toggle .icon {
  transition: transform var(--transition-fast);
}

.mobile-nav__toggle[aria-expanded="true"] .icon {
  transform: rotate(180deg);
}

.mobile-nav__submenu {
  padding-bottom: var(--space-3);
}

.mobile-nav__sublink {
  display: block;
  padding: var(--space-2) var(--space-4);
  color: rgb(255 255 255 / 0.9);
  text-decoration: none;
}

.mobile-nav__sublink[aria-current="page"] {
  color: var(--color-accent);
}

.mobile-nav__actions {
  display: grid;
  gap: var(--space-3);
  margin-block: var(--space-5);
}

.mobile-nav__social {
  margin-top: var(--space-4);
}

/* Lock page scroll while the mobile panel is open */
body.has-open-nav {
  overflow: hidden;
}

/* --- Desktop layout --------------------------------------------------------- */
@media (min-width: 64em) {
  .site-header__inner {
    grid-template-columns: auto 1fr auto;
    grid-template-areas:
      "brand . actions"
      "nav   nav nav";
    row-gap: 0;
    padding-block: var(--space-3) 0;
  }

  .primary-nav {
    display: block;
    margin-left: calc(-1 * var(--space-3));
  }

  .site-header__actions .site-header__cta {
    display: inline-flex;
  }

  .site-header__menu-toggle,
  .mobile-nav {
    display: none;
  }

  .brand__mark {
    width: 4rem;
    height: 4rem;
  }

  .brand__wordmark {
    font-size: var(--text-xl);
  }

  /* Compact state after scrolling: single row */
  .site-header.is-compact .site-header__inner {
    grid-template-areas: "brand nav actions";
    grid-template-columns: auto 1fr auto;
    column-gap: var(--space-6);
    padding-block: var(--space-2);
  }

  .site-header.is-compact .brand__mark {
    width: 2.75rem;
    height: 2.75rem;
  }

  .site-header.is-compact .brand__wordmark {
    display: none;
  }

  .site-header.is-compact .primary-nav__link {
    padding-block: var(--space-4);
  }
}

@media (min-width: 80em) {
  .primary-nav__list {
    gap: var(--space-4);
  }
}