/* Layout: Header, Navigation, Footer & Grid Systems */

/* Main Header */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--header-height);
  background: transparent;
  backdrop-filter: blur(0px);
  -webkit-backdrop-filter: blur(0px);
  border-bottom: 1px solid transparent;
  transition: all var(--transition-normal);
  z-index: 100;
}

.site-header.scrolled {
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom-color: var(--border-subtle);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

/* Brand Logo */
.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-weight: 700;
  font-size: 1.25rem;
  letter-spacing: -0.02em;
}

.brand-logo-img {
  height: 32px;
  width: auto;
  transition: opacity var(--transition-fast);
}

.logo-dark-mode {
  display: block;
}

.logo-light-mode {
  display: none;
}

[data-theme="light"] .logo-dark-mode {
  display: none;
}

[data-theme="light"] .logo-light-mode {
  display: block;
}

/* Desktop Navigation */
.main-nav {
  display: flex;
  align-items: center;
  gap: var(--space-xl);
}

.nav-link {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-secondary);
  position: relative;
  padding: 0.5rem 0;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--accent-primary);
  transition: width var(--transition-fast);
}

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

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.nav-link.active {
  color: var(--text-primary);
  font-weight: 600;
}

/* Header Actions */
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background: var(--bg-subtle);
  border: 1px solid var(--border-subtle);
  padding: 10px;
  z-index: 102;
}

.mobile-menu-toggle span {
  display: block;
  height: 2px;
  width: 100%;
  background-color: var(--text-primary);
  border-radius: 2px;
  transition: all var(--transition-fast);
}

.mobile-menu-toggle.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.mobile-menu-toggle.open span:nth-child(2) {
  opacity: 0;
}

.mobile-menu-toggle.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Mobile Navigation Drawer */
.mobile-drawer {
  position: fixed;
  top: 0;
  right: -100%;
  width: 100%;
  max-width: 400px;
  height: 100vh;
  background: var(--bg-surface);
  border-left: 1px solid var(--border-subtle);
  padding: calc(var(--header-height) + var(--space-xl)) var(--space-xl) var(--space-2xl);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: right var(--transition-normal);
  z-index: 101;
  box-shadow: -10px 0 30px rgba(0, 0, 0, 0.5);
}

.mobile-drawer.open {
  right: 0;
}

.mobile-drawer-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-normal);
  z-index: 100;
}

.mobile-drawer-backdrop.open {
  opacity: 1;
  pointer-events: auto;
}

.mobile-nav-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.mobile-nav-link {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--text-primary);
  transition: color var(--transition-fast);
}

.mobile-nav-link:hover {
  color: var(--accent-primary);
}

/* Grids */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-xl);
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-xl);
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-lg);
}

.grid-split {
  display: grid;
  grid-template-columns: 1fr 1.25fr;
  gap: var(--space-3xl);
  align-items: center;
}

/* Footer Section */
.site-footer {
  background: var(--bg-surface);
  border-top: 1px solid var(--border-subtle);
  padding-top: var(--space-4xl);
  padding-bottom: var(--space-2xl);
  position: relative;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.8fr 1fr 1fr 1.2fr;
  gap: var(--space-3xl);
  margin-bottom: var(--space-3xl);
}

.footer-brand-desc {
  margin-top: var(--space-md);
  margin-bottom: var(--space-lg);
  font-size: 0.9375rem;
  max-width: 320px;
}

.footer-col-title {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-tertiary);
  margin-bottom: var(--space-lg);
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-link {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  transition: color var(--transition-fast);
}

.footer-link:hover {
  color: var(--accent-primary);
}

.footer-contact-item {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  font-size: 0.9375rem;
  color: var(--text-secondary);
  margin-bottom: 0.75rem;
}

.footer-contact-item svg {
  flex-shrink: 0;
  margin-top: 0.25rem;
  color: var(--accent-primary);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-2xl);
  border-top: 1px solid var(--border-subtle);
  font-size: 0.875rem;
  color: var(--text-tertiary);
}

.footer-social-links {
  display: flex;
  gap: var(--space-md);
}

.footer-social-icon {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  transition: all var(--transition-fast);
}

.footer-social-icon:hover {
  background: var(--accent-primary);
  border-color: var(--accent-primary);
  color: #090d14;
  transform: translateY(-2px);
}