/* ==========================================================================
   hemingweb.com - Navigation Bar, Dropdowns, Mobile Drawer & Theme Toggle
   ========================================================================== */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  background: var(--surface-glass);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--surface-border);
  box-shadow: var(--shadow-sm);
  transition: background-color var(--transition-slow), border-color var(--transition-slow);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  max-width: 1200px;
  height: 4.25rem;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* --------------------------------------------------------------------------
   Brand Logo
   -------------------------------------------------------------------------- */
.brand-logo {
  display: inline-flex;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  text-decoration: none;
  letter-spacing: -0.03em;
  border-bottom: none;
  transition: color var(--transition-fast);
}

.brand-logo:hover {
  color: var(--accent-teal);
  border-bottom: none;
}

.brand-logo .accent {
  color: var(--accent-teal);
}

/* --------------------------------------------------------------------------
   Desktop Navigation
   -------------------------------------------------------------------------- */
.desktop-nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-item {
  position: relative;
}

.nav-link,
.dropdown-trigger {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.5rem 0.85rem;
  border-radius: var(--radius-md);
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-muted);
  text-decoration: none;
  background: transparent;
  border: 1px solid transparent;
  cursor: pointer;
  font-family: inherit;
  transition: all var(--transition-fast);
}

.nav-link:hover,
.dropdown-trigger:hover,
.dropdown-trigger[aria-expanded="true"] {
  color: var(--accent-teal);
  background: var(--surface-subtle);
  border-bottom-color: transparent;
}

.nav-link[aria-current="page"] {
  color: var(--accent-teal);
  font-weight: 600;
}

.dropdown-arrow {
  width: 0.65rem;
  height: 0.65rem;
  fill: currentColor;
  transition: transform var(--transition-fast);
}

.dropdown-trigger[aria-expanded="true"] .dropdown-arrow {
  transform: rotate(180deg);
}

/* --------------------------------------------------------------------------
   Dropdown Menus
   -------------------------------------------------------------------------- */
.dropdown-menu {
  position: absolute;
  top: calc(100% + 0.5rem);
  left: 0;
  min-width: 250px;
  background: var(--surface-glass-solid);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  padding: 0.5rem;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateY(-8px);
  transition: opacity var(--transition-fast), transform var(--transition-fast), visibility var(--transition-fast);
  z-index: 110;
  list-style: none;
}

.dropdown-menu.active {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateY(0);
}

.dropdown-menu li {
  margin: 0;
}

.dropdown-menu a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.65rem 0.85rem;
  border-radius: var(--radius-sm);
  color: var(--text-muted);
  font-size: 0.9rem;
  text-decoration: none;
  border-bottom: none;
  transition: all var(--transition-fast);
}

.dropdown-menu a:hover {
  background: var(--surface-subtle);
  color: var(--accent-teal);
  border-bottom: none;
  transform: translateX(2px);
}

.dropdown-menu a .item-title {
  font-weight: 500;
}

.dropdown-menu a .item-desc {
  font-size: 0.75rem;
  color: var(--text-dim);
  display: block;
}

.dropdown-divider {
  height: 1px;
  background: var(--surface-border);
  margin: 0.4rem 0;
}

/* --------------------------------------------------------------------------
   Theme Toggle Button
   -------------------------------------------------------------------------- */
.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.35rem;
  height: 2.35rem;
  border-radius: var(--radius-full);
  background: var(--surface-subtle);
  border: 1px solid var(--surface-border);
  color: var(--text-primary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.theme-toggle:hover {
  background: var(--surface-border);
  color: var(--accent-teal);
  transform: scale(1.05);
}

.theme-toggle svg {
  width: 1.15rem;
  height: 1.15rem;
  fill: currentColor;
}

/* Light/Dark icon visibility */
.icon-sun {
  display: none;
}
.icon-moon {
  display: block;
}

:root[color-scheme="light"] .icon-sun,
html[data-theme="light"] .icon-sun {
  display: block;
}

:root[color-scheme="light"] .icon-moon,
html[data-theme="light"] .icon-moon {
  display: none;
}

/* --------------------------------------------------------------------------
   Mobile Hamburger Toggle
   -------------------------------------------------------------------------- */
.mobile-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: var(--radius-md);
  background: var(--surface-subtle);
  border: 1px solid var(--surface-border);
  color: var(--text-primary);
  cursor: pointer;
}

.mobile-toggle svg {
  width: 1.35rem;
  height: 1.35rem;
  fill: currentColor;
}

/* --------------------------------------------------------------------------
   Mobile Drawer & Overlay (With Explicit pointer-events protection)
   -------------------------------------------------------------------------- */
.nav-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(4px);
  z-index: 190;
  opacity: 0;
  visibility: hidden;
  pointer-events: none; /* CRITICAL: Prevents blocking clicks when inactive */
  transition: opacity var(--transition-normal), visibility var(--transition-normal);
}

.nav-overlay.active {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.mobile-drawer {
  position: fixed;
  top: 0;
  right: 0;
  width: 82%;
  max-width: 340px;
  height: 100%;
  background: var(--surface-glass-solid);
  border-left: 1px solid var(--surface-border);
  box-shadow: var(--shadow-lg);
  z-index: 200;
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  transform: translateX(100%);
  transition: transform var(--transition-slow);
  overflow-y: auto;
  pointer-events: none;
}

.mobile-drawer.active {
  transform: translateX(0);
  pointer-events: auto;
}

.drawer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--surface-border);
  margin-bottom: 1.25rem;
}

.drawer-close {
  background: transparent;
  border: none;
  color: var(--text-primary);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 0.25rem;
}

.drawer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.drawer-links .nav-link {
  width: 100%;
  padding: 0.75rem 0.5rem;
  font-size: 1.05rem;
}

.drawer-section-title {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dim);
  padding: 0.75rem 0.5rem 0.25rem;
  margin-top: 0.5rem;
}

.drawer-sublinks {
  list-style: none;
  padding-left: 0.75rem;
}

.drawer-sublinks a {
  display: block;
  padding: 0.5rem;
  color: var(--text-muted);
  text-decoration: none;
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
}

.drawer-sublinks a:hover {
  color: var(--accent-teal);
  background: var(--surface-subtle);
}

.drawer-footer {
  margin-top: auto;
  padding-top: 1.5rem;
  border-top: 1px solid var(--surface-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

/* --------------------------------------------------------------------------
   Responsive Breakpoints
   -------------------------------------------------------------------------- */
@media (max-width: 860px) {
  .desktop-nav {
    display: none;
  }
  .mobile-toggle {
    display: inline-flex;
  }
}