/* ============================================================
   HEADER / NAVIGATION
   ============================================================ */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: color-mix(in srgb, var(--color-bg) 92%, transparent);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--color-divider);
  transition: box-shadow 0.3s ease, background 0.3s ease;
}

.site-header.scrolled {
  box-shadow: var(--shadow-md);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 4.5rem;
  gap: var(--space-8);
}

/* Logo */
.site-logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-shrink: 0;
  text-decoration: none;
}

.logo-mark {
  width: 2.5rem;
  height: 2.5rem;
  flex-shrink: 0;
}

.logo-text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}

.logo-name {
  font-family: var(--font-display);
  font-size: clamp(1rem, 0.9rem + 0.3vw, 1.2rem);
  font-weight: 600;
  color: var(--color-text);
  letter-spacing: 0.01em;
}

.logo-sub {
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: 400;
  color: var(--color-text-muted);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

/* Nav Links */
.main-nav {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.nav-link {
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: 400;
  color: var(--color-text-muted);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-sm);
  letter-spacing: 0.01em;
  white-space: nowrap;
}

.nav-link:hover {
  color: var(--color-text);
  background: var(--color-surface-offset);
}

.nav-link.active {
  color: var(--color-primary);
  font-weight: 500;
}

/* Header Actions */
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-shrink: 0;
}

.theme-toggle {
  width: 2rem;
  height: 2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
  border: 1px solid var(--color-border);
}

.theme-toggle:hover {
  color: var(--color-text);
  background: var(--color-surface-offset);
}

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: var(--space-2);
  cursor: pointer;
}

.hamburger span {
  width: 22px;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: all 0.3s ease;
}

/* Mobile Nav Drawer */
.mobile-nav {
  display: none;
  flex-direction: column;
  gap: var(--space-1);
  padding: var(--space-4) 0 var(--space-6);
  border-top: 1px solid var(--color-divider);
  background: var(--color-bg);
}

.mobile-nav.open {
  display: flex;
}

.mobile-nav .nav-link {
  padding: var(--space-3) var(--space-4);
  font-size: var(--text-base);
  border-radius: 0;
  border-bottom: 1px solid var(--color-divider);
}

.mobile-nav .btn {
  margin: var(--space-4) var(--space-4) 0;
  justify-content: center;
}

/* ============================================================
   FOOTER
   ============================================================ */

.site-footer {
  background: var(--color-navy);
  color: rgba(255,255,255,0.75);
  padding-block: clamp(var(--space-12), 6vw, var(--space-20));
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-10);
  margin-bottom: var(--space-12);
}

.footer-brand .logo-name,
.footer-brand .logo-sub {
  color: rgba(255,255,255,0.9);
}

.footer-brand .logo-sub {
  color: rgba(255,255,255,0.5);
}

.footer-tagline {
  font-size: var(--text-sm);
  line-height: 1.7;
  color: rgba(255,255,255,0.6);
  margin-top: var(--space-4);
  max-width: 26ch;
}

.footer-heading {
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.4);
  margin-bottom: var(--space-4);
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.footer-links a {
  font-size: var(--text-sm);
  color: rgba(255,255,255,0.65);
  transition: color var(--transition-interactive);
}

.footer-links a:hover {
  color: var(--color-primary);
}

.footer-bottom {
  padding-top: var(--space-6);
  border-top: 1px solid rgba(255,255,255,0.1);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
}

.footer-legal {
  font-size: var(--text-xs);
  color: rgba(255,255,255,0.35);
}

.footer-legal a {
  color: rgba(255,255,255,0.45);
}

.footer-legal a:hover {
  color: var(--color-primary);
}

.footer-attribution {
  font-size: var(--text-xs);
  color: rgba(255,255,255,0.3);
}

.footer-attribution a {
  color: rgba(255,255,255,0.4);
}

.footer-attribution a:hover {
  color: var(--color-primary);
}

/* Responsive */
@media (max-width: 1024px) {
  .main-nav { display: none; }
  .hamburger { display: flex; }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-8);
  }
}

@media (max-width: 640px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--space-6);
  }
  .header-cta { display: none; }
}