/* =========================================================
   NeuroTek Digital — Header & Navigation
   File: assets/css/header.css
   ========================================================= */

/* ─── Site Header ─── */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 0 var(--space-5);
  transition: background var(--transition-slow), backdrop-filter var(--transition-slow), box-shadow var(--transition-slow);
}

.site-header.scrolled {
  background: rgba(5, 9, 20, 0.9);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: 0 1px 0 var(--border-subtle), 0 8px 32px rgba(0,0,0,0.4);
}

.header-inner {
  max-width: 1280px;
  margin: 0 auto;
  height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-5);
}

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

.logo-mark {
  width: 36px;
  height: 36px;
  border-radius: 9px;
  background: linear-gradient(135deg, var(--brand-blue), var(--brand-cyan));
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1rem;
  color: #fff;
  letter-spacing: -0.02em;
  flex-shrink: 0;
  position: relative;
  overflow: hidden;
}

.logo-mark::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255,255,255,0.15), transparent);
}

.logo-text {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1rem;
  letter-spacing: -0.01em;
  color: var(--text-primary);
  line-height: 1.2;
}

.logo-text span {
  color: var(--brand-cyan);
}

.logo-sub {
  font-family: var(--font-mono);
  font-size: 0.6rem;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  text-transform: uppercase;
}

/* ─── Desktop Navigation ─── */
.nav-desktop {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.nav-link {
  font-family: var(--font-display);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  transition: color var(--transition-fast), background var(--transition-fast);
  white-space: nowrap;
}

.nav-link:hover {
  color: var(--text-primary);
  background: rgba(255,255,255,0.05);
}

.nav-link.active {
  color: var(--brand-cyan);
}

/* Dropdown */
.nav-item {
  position: relative;
}

.nav-dropdown {
  position: absolute;
  top: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%);
  min-width: 200px;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: var(--space-2) 0;
  opacity: 0;
  visibility: hidden;
  transform: translateX(-50%) translateY(-8px);
  transition: all var(--transition-base);
  box-shadow: var(--shadow-lg);
  backdrop-filter: blur(16px);
}

.nav-item:hover .nav-dropdown,
.nav-item:focus-within .nav-dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

.nav-dropdown a {
  display: block;
  padding: 10px var(--space-4);
  font-size: 0.85rem;
  color: var(--text-secondary);
  transition: color var(--transition-fast), background var(--transition-fast);
}
.nav-dropdown a:hover {
  color: var(--text-primary);
  background: rgba(255,255,255,0.04);
}

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

/* ─── Mobile Menu Toggle ─── */
.nav-mobile-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: var(--space-2);
  cursor: pointer;
  border-radius: var(--radius-sm);
  transition: background var(--transition-fast);
}

.nav-mobile-toggle:hover { background: rgba(255,255,255,0.05); }

.nav-mobile-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-secondary);
  border-radius: 2px;
  transition: all var(--transition-base);
}

.nav-mobile-toggle.open span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.nav-mobile-toggle.open span:nth-child(2) { opacity: 0; transform: scaleX(0); }
.nav-mobile-toggle.open span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* ─── Mobile Navigation Drawer ─── */
.nav-mobile {
  display: none;
  position: fixed;
  top: 72px;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(5, 9, 20, 0.98);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  z-index: 999;
  padding: var(--space-6) var(--space-5);
  overflow-y: auto;
  flex-direction: column;
  gap: var(--space-2);
  opacity: 0;
  transform: translateX(100%);
  transition: opacity var(--transition-base), transform var(--transition-base);
}

.nav-mobile.open {
  opacity: 1;
  transform: translateX(0);
}

.nav-mobile .nav-link {
  display: block;
  font-size: 1.25rem;
  font-weight: 600;
  padding: var(--space-3) 0;
  border-bottom: 1px solid var(--border-subtle);
}

.nav-mobile-section-label {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--text-muted);
  padding: var(--space-4) 0 var(--space-2);
}

.nav-mobile-sub a {
  display: block;
  font-size: 0.95rem;
  color: var(--text-secondary);
  padding: var(--space-2) 0;
  border-bottom: 1px solid rgba(255,255,255,0.04);
  transition: color var(--transition-fast);
}
.nav-mobile-sub a:hover { color: var(--brand-cyan); }

.nav-mobile-cta {
  margin-top: var(--space-5);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

/* ─── Responsive ─── */
@media (max-width: 1024px) {
  .nav-desktop { display: none; }
  .nav-mobile-toggle { display: flex; }
  .nav-mobile { display: flex; }
  .header-cta .btn { display: none; }
  .header-cta .btn:last-child { display: inline-flex; }
}

@media (max-width: 480px) {
  .header-cta { display: none; }
}