/* ==========================================================================
   TOOLPULSE HEADER & NAVIGATION (Theme Adaptive)
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  width: 100%;
  height: var(--header-height);
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}

.site-header .header-container {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  width: min(calc(100% - 40px), var(--container));
  margin-inline: auto;
}

/* Branding Logo */
.site-logo-link {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--color-text);
  font-family: 'Manrope', sans-serif;
  font-size: 22px;
  font-weight: 800;
  letter-spacing: -0.03em;
  text-decoration: none;
  white-space: nowrap;
}

.site-logo-link:hover {
  text-decoration: none;
}

.site-logo {
  display: block;
  height: 32px;
  width: auto;
}

/* Primary Desktop Navigation Menu */
.main-navigation {
  margin-left: auto;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 24px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.nav-menu a {
  position: relative;
  color: var(--color-muted);
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
  padding: 8px 4px;
  transition: color 0.2s ease;
}

.nav-menu a:hover,
.nav-menu a:focus-visible {
  color: var(--color-primary);
  text-decoration: none;
}

/* Accessibility Focus States across header items */
.nav-menu a:focus-visible,
.site-logo-link:focus-visible,
.theme-toggle-btn:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--color-primary) 55%, transparent);
  outline-offset: 4px;
  border-radius: var(--radius-sm);
}

/* Interactive Light/Dark Theme Toggle Button */
.theme-toggle-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  color: var(--color-text);
  font-size: 1.1rem;
  transition: background 0.2s ease, border-color 0.2s ease, transform 0.1s ease;
}

.theme-toggle-btn:hover {
  background: var(--color-primary-soft);
  border-color: var(--color-primary);
}

.theme-toggle-btn:active {
  transform: scale(0.95);
}

/* Responsive Mobile Layout Tweak Hook */
@media (max-width: 960px) {
  .site-header {
    height: auto;
    padding-vertical: 12px;
  }
  
  .site-header .header-container {
    flex-wrap: wrap;
    padding-block: 12px;
  }

  .main-navigation {
    order: 3;
    width: 100%;
    margin-top: 12px;
    overflow-x: auto;
    padding-bottom: 4px;
    -webkit-overflow-scrolling: touch;
  }

  .nav-menu {
    gap: 16px;
    justify-content: flex-start;
  }
  
  .nav-menu a {
    font-size: 13px;
  }
}