/* ==========================================================================
   Header — Nocturne Brass
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: var(--color-ink);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition-fast);
}

.site-header.is-scrolled {
  border-bottom-color: var(--color-brass);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-lg);
  max-width: var(--container-max-width);
  margin-inline: auto;
  padding-inline: var(--container-padding-mobile);
  height: 72px;
}

.site-header__brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  flex-shrink: 0;
  min-width: 0;
}

.site-header__logo {
  width: 40px;
  height: 40px;
  object-fit: contain;
  flex-shrink: 0;
}

.site-header__brand-text {
  font-family: var(--font-heading);
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--color-parchment);
  white-space: nowrap;
}

.site-header__toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  padding: 0;
  background: transparent;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-sm);
  cursor: pointer;
  flex-shrink: 0;
}

.site-header__toggle-icon,
.site-header__toggle-icon::before,
.site-header__toggle-icon::after {
  display: block;
  width: 20px;
  height: 2px;
  background-color: var(--color-parchment);
  border-radius: 1px;
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

.site-header__toggle-icon {
  position: relative;
}

.site-header__toggle-icon::before,
.site-header__toggle-icon::after {
  content: "";
  position: absolute;
  left: 0;
}

.site-header__toggle-icon::before {
  top: -6px;
}

.site-header__toggle-icon::after {
  top: 6px;
}

.site-header__toggle[aria-expanded="true"] .site-header__toggle-icon {
  background-color: transparent;
}

.site-header__toggle[aria-expanded="true"] .site-header__toggle-icon::before {
  transform: translateY(6px) rotate(45deg);
}

.site-header__toggle[aria-expanded="true"] .site-header__toggle-icon::after {
  transform: translateY(-6px) rotate(-45deg);
}

.site-header__toggle:focus-visible {
  outline: var(--focus-outline-width) solid var(--focus-outline-color);
  outline-offset: var(--focus-outline-offset);
}

.site-header__nav {
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

.site-header__nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-header__nav-item {
  margin: 0;
  padding: 0;
}

.site-header__nav-link {
  display: inline-block;
  font-family: var(--font-body);
  font-size: var(--font-size-small);
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-parchment);
  text-decoration: none;
  padding-block: var(--space-xs);
  position: relative;
  transition: color var(--transition-fast);
}

.site-header__nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background-color: var(--color-brass);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-fast);
}

.site-header__nav-link:hover {
  color: var(--color-brass);
}

.site-header__nav-link:hover::after,
.site-header__nav-link[aria-current="page"]::after {
  transform: scaleX(1);
}

.site-header__nav-link[aria-current="page"] {
  color: var(--color-brass);
}

.site-header__nav-link:focus-visible {
  outline: var(--focus-outline-width) solid var(--focus-outline-color);
  outline-offset: var(--focus-outline-offset);
}

/* Mobile navigation */
@media (max-width: 767px) {
  .site-header__inner {
    height: 64px;
  }

  .site-header__logo {
    width: 34px;
    height: 34px;
  }

  .site-header__brand-text {
    font-size: 13px;
    letter-spacing: 0.06em;
  }

  .site-header__toggle {
    display: inline-flex;
  }

  .site-header__nav {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--color-charcoal);
    padding: var(--space-lg);
    overflow-y: auto;
    transform: translateX(100%);
    transition: transform var(--transition-fast);
    visibility: hidden;
    z-index: 999;
  }

  .site-header__nav.is-open {
    transform: translateX(0);
    visibility: visible;
  }

  .site-header__nav-list {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-md);
  }

  .site-header__nav-link {
    font-size: var(--font-size-h4);
    letter-spacing: 0.04em;
    text-transform: none;
    padding-block: var(--space-sm);
  }

  .site-header__nav-link::after {
    display: none;
  }
}

@media (min-width: 768px) and (max-width: 1023px) {
  .site-header__inner {
    height: 72px;
  }

  .site-header__logo {
    width: 36px;
    height: 36px;
  }

  .site-header__brand-text {
    font-size: 14px;
    letter-spacing: 0.07em;
  }

  .site-header__nav-list {
    gap: var(--space-md);
  }

  .site-header__nav-link {
    font-size: 13px;
    letter-spacing: 0.06em;
  }
}