/**
 * Фиксированная шапка и навигация
 */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: var(--z-header);
  height: var(--header-height);
  background-color: rgba(247, 244, 239, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition:
    background-color var(--transition-base),
    border-color var(--transition-base),
    box-shadow var(--transition-base);
}

.site-header.is-scrolled {
  background-color: rgba(255, 255, 255, 0.95);
  border-bottom-color: var(--color-border);
  box-shadow: var(--shadow-sm);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  height: 100%;
}

/* ── Логотип ── */

.site-logo {
  flex-shrink: 0;
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: var(--weight-medium);
  color: var(--color-primary);
  letter-spacing: -0.01em;
  transition: color var(--transition-fast);
}

.site-logo:hover {
  color: var(--color-primary-hover);
}

.site-logo__underscore {
  color: var(--color-accent);
}

/* ── Навигация (desktop) ── */

.site-nav {
  display: none;
}

@media (min-width: 1024px) {
  .site-nav {
    display: flex;
    align-items: center;
    gap: var(--space-1);
  }
}

.site-nav__link {
  position: relative;
  padding: var(--space-2) var(--space-3);
  font-size: var(--text-sm);
  font-weight: var(--weight-regular);
  color: var(--color-text-muted);
  border-radius: var(--radius-sm);
  transition:
    color var(--transition-fast),
    background-color var(--transition-fast);
}

.site-nav__link::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: var(--space-3);
  right: var(--space-3);
  height: 2px;
  background: var(--color-accent);
  border-radius: var(--radius-full);
  transform: scaleX(0);
  transform-origin: center;
  transition: transform var(--transition-base);
}

.site-nav__link:hover {
  color: var(--color-primary);
  background-color: var(--color-primary-soft);
}

.site-nav__link.is-active {
  color: var(--color-primary);
  font-weight: var(--weight-medium);
}

.site-nav__link.is-active::after {
  transform: scaleX(1);
}

/* ── CTA в шапке ── */

.site-header__actions {
  display: none;
  align-items: center;
  gap: var(--space-4);
}

@media (min-width: 1024px) {
  .site-header__actions {
    display: flex;
    flex-shrink: 0;
  }
}

.site-header__cta {
  padding: var(--space-2) var(--space-5);
  font-size: var(--text-sm);
  white-space: nowrap;
}

/* ── Burger (mobile) ── */

.burger {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 2.75rem;
  height: 2.75rem;
  padding: var(--space-2);
  border-radius: var(--radius-md);
  transition: background-color var(--transition-fast);
}

.burger:hover {
  background-color: var(--color-primary-soft);
}

@media (min-width: 1024px) {
  .burger {
    display: none;
  }
}

.burger__line {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--color-text);
  border-radius: 1px;
  transition:
    transform var(--transition-base),
    opacity var(--transition-base);
}

.burger[aria-expanded="true"] .burger__line:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.burger[aria-expanded="true"] .burger__line:nth-child(2) {
  opacity: 0;
}

.burger[aria-expanded="true"] .burger__line:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ── Mobile menu ── */

.mobile-menu {
  position: fixed;
  inset: 0;
  top: var(--header-height);
  z-index: var(--z-menu);
  display: flex;
  flex-direction: column;
  padding: var(--space-6) var(--container-padding);
  background-color: var(--color-bg);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-8px);
  transition:
    opacity var(--transition-base),
    visibility var(--transition-base),
    transform var(--transition-base);
  overflow-y: auto;
}

.mobile-menu.is-open {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

@media (min-width: 1024px) {
  .mobile-menu {
    display: none;
  }
}

.mobile-menu__nav {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.mobile-menu__link {
  display: block;
  padding: var(--space-4) var(--space-3);
  padding-left: var(--space-5);
  font-size: var(--text-lg);
  font-weight: var(--weight-medium);
  color: var(--color-text);
  border-radius: var(--radius-md);
  border-left: 3px solid transparent;
  transition:
    color var(--transition-fast),
    background-color var(--transition-fast),
    border-color var(--transition-fast);
}

.mobile-menu__link:hover,
.mobile-menu__link.is-active {
  color: var(--color-primary);
  background-color: var(--color-primary-soft);
  border-left-color: var(--color-accent);
}

.mobile-menu__cta {
  margin-top: var(--space-8);
  width: 100%;
}

/* Overlay */
.mobile-menu__overlay {
  position: fixed;
  inset: 0;
  top: var(--header-height);
  z-index: var(--z-overlay);
  background-color: rgba(42, 42, 42, 0.2);
  opacity: 0;
  visibility: hidden;
  transition:
    opacity var(--transition-base),
    visibility var(--transition-base);
}

.mobile-menu__overlay.is-visible {
  opacity: 1;
  visibility: visible;
}

@media (min-width: 1024px) {
  .mobile-menu__overlay {
    display: none;
  }
}