/* =============================================================
   HEADER — Fixed navigation bar
   ============================================================= */

.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: var(--z-header);
  background-color: transparent;
  transition:
    background-color var(--transition-base),
    box-shadow var(--transition-base),
    backdrop-filter var(--transition-base);
}

.header.header--scrolled {
  background-color: rgba(13, 13, 13, 0.95);
  backdrop-filter: blur(12px);
  box-shadow: 0 1px 0 var(--color-border-dark);
}

.header__container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--container-padding);
  padding-block: 1.25rem;
}

.header__logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  text-decoration: none;
}

.header__logo-text {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text-on-dark);
  letter-spacing: -0.02em;
}

.header__logo-text span {
  color: var(--color-accent);
}

.header__nav {
  display: none;
}

.header__nav-list {
  display: flex;
  align-items: center;
  gap: 2rem;
  list-style: none;
}

.header__nav-item {
  /* structural only */
}

.header__nav-link {
  font-family: var(--font-body);
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--color-text-on-dark-muted);
  text-decoration: none;
  transition: color var(--transition-base);
}

.header__nav-link:hover {
  color: var(--color-text-on-dark);
}

.header__nav-link.header__nav-link--active {
  color: var(--color-accent);
}

.header__cta {
  display: none;
}

.header__menu-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: var(--radius-md);
  color: var(--color-text-on-dark);
  background: transparent;
  border: 1px solid var(--color-border-dark);
  cursor: pointer;
  transition:
    background-color var(--transition-base),
    border-color var(--transition-base);
}

.header__menu-toggle:hover {
  background-color: var(--color-primary-light);
  border-color: var(--color-primary-muted);
}

/* Mobile nav drawer */
.header__mobile-nav {
  display: none;
  flex-direction: column;
  gap: 0;
  background-color: var(--color-primary-dark);
  border-top: 1px solid var(--color-border-dark);
  padding: var(--spacing-lg) var(--container-padding);
}

.header.header--open .header__mobile-nav {
  display: flex;
}

.header__mobile-nav-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  list-style: none;
  margin-bottom: var(--spacing-lg);
}

.header__mobile-nav-link {
  display: block;
  padding: 0.75rem 0;
  font-family: var(--font-body);
  font-size: 1rem;
  font-weight: 500;
  color: var(--color-text-on-dark-muted);
  text-decoration: none;
  border-bottom: 1px solid var(--color-border-dark);
  transition: color var(--transition-base);
}

.header__mobile-nav-link:hover {
  color: var(--color-text-on-dark);
}

/* Desktop breakpoint */
@media (min-width: 1024px) {
  .header__nav {
    display: flex;
    align-items: center;
  }

  .header__cta {
    display: inline-flex;
  }

  .header__menu-toggle {
    display: none;
  }
}