/* === Шапка и навигация === */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}

.site-header.is-menu-open {
  border-bottom-color: transparent;
}

.site-header__inner {
  position: relative;
  z-index: 2;
  width: var(--container);
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 1rem;
  max-width: 1120px;
}

.logo {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.logo__accent {
  color: var(--accent);
}

.logo__name {
  color: var(--text);
}

.logo__muted {
  color: var(--text-muted);
}

.logo--link {
  color: var(--text);
  text-decoration: none;
  display: inline-flex;
  align-items: baseline;
  gap: 0.35rem;
  flex-wrap: wrap;
}

/* Анимация первого слова логотипа (Игоряновский ↔ Инженерный) */
.animated-word {
  display: inline-block;
  min-width: var(--brand-slot-min-width, 150px);
  color: inherit;
  transition: opacity var(--brand-word-transition, 0.2s) ease;
}

.logo__slot--static {
  display: inline-flex;
  align-items: baseline;
  flex-wrap: nowrap;
  gap: 0;
}

.logo__slot--rotate {
  display: inline-block;
}

/* Десктопная навигация */
.site-nav {
  display: none;
  align-items: center;
  gap: 1.75rem;
}

.site-nav a,
.site-nav a.site-nav__link {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  position: relative;
  padding-bottom: 0.35rem;
  color: var(--text-muted);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.95rem;
}

.site-nav a .site-nav-icon {
  font-size: 0.95em;
  line-height: 1;
  flex-shrink: 0;
  color: inherit;
}

.site-nav a:hover,
.site-nav a:focus-visible {
  color: var(--text);
}

.site-nav a[aria-current='page'] {
  color: var(--text);
  font-weight: 600;
}

.site-nav a[aria-current='page']::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: var(--accent);
}

/* Кнопка мобильного меню */
.nav-toggle {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  width: 44px;
  height: 44px;
  padding: 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-nav-toggle, 0);
  cursor: pointer;
}

.nav-toggle:hover,
.nav-toggle:focus-visible {
  border-color: var(--accent-muted);
  background: var(--surface-2);
}

.nav-toggle__bar {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--text);
  transition: transform var(--nav-toggle-duration, 0.25s) ease, opacity 0.2s ease;
}

.site-header.is-menu-open .nav-toggle__bar:nth-child(1) {
  transform: translateY(8px) rotate(45deg);
}

.site-header.is-menu-open .nav-toggle__bar:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}

.site-header.is-menu-open .nav-toggle__bar:nth-child(3) {
  transform: translateY(-8px) rotate(-45deg);
}

/* Оверлей мобильного меню */
.site-nav-overlay {
  position: fixed;
  inset: 0;
  top: var(--site-header-bar-height, 56px);
  z-index: 0;
  background: var(--header-overlay-bg, rgba(12, 12, 14, 0.78));
  cursor: pointer;
  animation: site-overlay-in var(--overlay-animation-duration, 0.25s) ease forwards;
}

.site-nav-overlay[hidden] {
  display: none !important;
}

@keyframes site-overlay-in {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

/* Мобильное меню */
.site-menu {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  width: var(--container);
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 1rem 1.25rem;
  padding-bottom: calc(1.25rem + 14px);
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  clip-path: var(--torn-small);
  box-shadow: var(--shadow-mobile-menu, 0 18px 40px rgba(0, 0, 0, 0.35));
}

.site-menu[hidden] {
  display: none !important;
}

.site-menu__link {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.55rem;
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  text-decoration: none;
  text-align: center;
  color: var(--text);
  padding: 0.95rem 1.25rem;
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  transition: border-color 0.2s ease, color 0.2s ease;
}

.site-menu__link .site-nav-icon {
  font-size: 1.05em;
  line-height: 1;
  flex-shrink: 0;
  color: inherit;
}

.site-menu__link:hover {
  border-color: var(--accent-muted);
  color: var(--accent);
}

/* Медиа-запросы для навигации */
@media (min-width: 768px) {
  .site-nav {
    display: flex;
  }
  .nav-toggle {
    display: none;
  }
  .site-menu {
    display: none !important;
  }
  .site-nav-overlay {
    display: none !important;
  }
}

.logo--link:hover {
  color: var(--text);
}

.logo--link:hover .logo__accent {
  color: var(--accent-hover, var(--accent));
}