.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background-color: rgba(10, 14, 26, 0.92);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid rgba(0, 229, 255, 0.2);
  box-shadow: 0 0 12px rgba(0, 229, 255, 0.15);
}

.site-header__inner {
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--container-padding);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  min-height: 64px;
}

.site-header__brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--color-starlight-white);
  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: 1.125rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--color-starlight-white);
  white-space: nowrap;
}

.site-header__toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 0;
  background: transparent;
  border: 1px solid rgba(0, 229, 255, 0.3);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
  flex-shrink: 0;
}

.site-header__toggle:hover {
  border-color: var(--color-electric-cyan);
  box-shadow: var(--glow-cyan);
}

.site-header__toggle:focus-visible {
  outline: var(--focus-ring-width) solid var(--focus-ring-color);
  outline-offset: 2px;
  box-shadow: 0 0 16px var(--focus-ring-glow);
}

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

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

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

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

.site-header__nav {
  display: flex;
  align-items: center;
  flex-shrink: 1;
  min-width: 0;
}

.site-header__nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-5);
  list-style: none;
  margin: 0;
  padding: 0;
}

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

.site-header__nav-link {
  display: inline-block;
  padding: var(--space-2) var(--space-1);
  font-family: var(--font-heading);
  font-size: 0.9375rem;
  font-weight: 500;
  letter-spacing: 0.01em;
  color: var(--color-starlight-white);
  text-decoration: none;
  white-space: nowrap;
  transition: color var(--transition-fast), text-shadow var(--transition-fast);
  position: relative;
}

.site-header__nav-link::after {
  content: "";
  position: absolute;
  left: var(--space-1);
  right: var(--space-1);
  bottom: 0;
  height: 2px;
  background-color: var(--color-electric-cyan);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-fast);
}

.site-header__nav-link:hover {
  color: var(--color-radiant-gold);
  text-shadow: 0 0 8px var(--color-crystal-glow);
}

.site-header__nav-link:hover::after {
  transform: scaleX(1);
}

.site-header__nav-link:focus-visible {
  outline: var(--focus-ring-width) solid var(--focus-ring-color);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
  box-shadow: 0 0 12px var(--focus-ring-glow);
}

@media (max-width: 1023px) {
  .site-header__toggle {
    display: flex;
  }

  .site-header__nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: rgba(10, 14, 26, 0.98);
    border-bottom: 1px solid rgba(0, 229, 255, 0.2);
    box-shadow: 0 12px 24px rgba(0, 0, 0, 0.5);
    max-height: calc(100vh - 64px);
    overflow-y: auto;
    display: none;
    padding: var(--space-4) var(--container-padding);
  }

  .site-header__nav.is-open {
    display: block;
  }

  .site-header__nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-2);
  }

  .site-header__nav-link {
    display: block;
    padding: var(--space-3) var(--space-2);
    font-size: 1rem;
    border-radius: var(--radius-sm);
  }

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

  .site-header__nav-link:hover {
    background-color: rgba(0, 229, 255, 0.08);
  }
}

@media (min-width: 1024px) {
  .site-header__inner {
    min-height: 72px;
  }

  .site-header__logo {
    width: 44px;
    height: 44px;
  }

  .site-header__brand-text {
    font-size: 1.25rem;
  }

  .site-header__nav-list {
    gap: var(--space-6);
  }

  .site-header__nav-link {
    font-size: 1rem;
  }
}

@media (max-width: 767px) {
  .site-header__inner {
    min-height: 56px;
    padding-inline: var(--space-4);
  }

  .site-header__logo {
    width: 32px;
    height: 32px;
  }

  .site-header__brand-text {
    font-size: 1rem;
  }

  .site-header__toggle {
    width: 40px;
    height: 40px;
  }

  .site-header__nav {
    max-height: calc(100vh - 56px);
    padding: var(--space-3) var(--space-4);
  }
}