/* ═══════════════════════════════════════════
   NAV.CSS — Sticky header, mobile drawer
═══════════════════════════════════════════ */

/* ── Site Header ── */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  z-index: 1000;
  background: var(--color-header-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--color-border-subtle);
  transition: background var(--duration-base) var(--ease-default),
              box-shadow var(--duration-base) var(--ease-default);
}

.site-header.scrolled {
  background: var(--color-header-scrolled);
  box-shadow: var(--shadow-header, 0 4px 24px rgba(0, 0, 0, 0.4));
}

/* ── Nav Container ── */
.container-nav {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--container-pad);
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-6);
}

/* ── Logo ── */
.logo-link {
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

.logo-img {
  height: 34px;
  width: auto;
  display: block;
  transition: opacity var(--duration-base);
}
.logo-link:hover .logo-img {
  opacity: 0.85;
}

/* ── Desktop Nav ── */
.desktop-nav {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  /* Right-aligned: pushed to the right by nav-actions flex layout */
}

.nav-link {
  font-size: var(--text-sm);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-muted);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-sm);
  position: relative;
  transition: color var(--duration-base) var(--ease-default);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: var(--space-3);
  right: var(--space-3);
  height: 1.5px;
  background: var(--color-blue);
  transform: scaleX(0);
  transform-origin: center;
  transition: transform var(--duration-base) var(--ease-default);
}

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

.nav-link:hover::after {
  transform: scaleX(1);
}

/* ── Nav Actions ── */
.nav-right-group {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-shrink: 0;
}

/* Theme Toggle */
.theme-toggle {
  background: transparent;
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  width: 38px;
  height: 38px;
  border-radius: var(--radius-full);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
  transition: all var(--duration-base) var(--ease-default);
}
.theme-toggle:hover {
  border-color: var(--color-blue);
  color: var(--color-blue);
  background: rgba(0, 131, 143, 0.08);
}
/* Theme icon transitions */
.theme-toggle .sun-icon {
  transform: scale(0) rotate(-90deg);
  opacity: 0;
  transition: transform var(--duration-base) var(--ease-default), opacity var(--duration-base);
  position: absolute;
}
.theme-toggle .moon-icon {
  transform: scale(1) rotate(0deg);
  opacity: 1;
  transition: transform var(--duration-base) var(--ease-default), opacity var(--duration-base);
}
html[data-theme="light"] .theme-toggle .sun-icon {
  transform: scale(1) rotate(0deg);
  opacity: 1;
}
html[data-theme="light"] .theme-toggle .moon-icon {
  transform: scale(0) rotate(90deg);
  opacity: 0;
}

/* Language Toggle */
.lang-toggle {
  background: transparent;
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-family: var(--font-display);
  font-size: var(--text-xs);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  width: 38px;
  height: 38px;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: all var(--duration-base) var(--ease-default);
}
.lang-toggle:hover {
  border-color: var(--color-blue);
  color: var(--color-blue);
}

/* Access App CTA */
.btn-access {
  font-family: var(--font-display);
  font-size: var(--text-xs);
  font-weight: 700;
  padding: var(--space-2) var(--space-5);
  background: var(--gradient-brand);
  color: #0C0F19;
  border-radius: var(--radius-full);
  white-space: nowrap;
  transition: transform var(--duration-base) var(--ease-default),
              box-shadow var(--duration-base) var(--ease-default);
}
.btn-access:hover {
  transform: scale(1.05);
  box-shadow: var(--glow-blue-sm);
  color: #0C0F19;
}

/* ── Mobile Menu Toggle ── */
.menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 28px;
  height: 20px;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 0;
  z-index: 1100;
}

.menu-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--color-text-muted);
  border-radius: 2px;
  transition: all var(--duration-base) var(--ease-default);
}

.site-header.is-open .menu-toggle span:nth-child(1) {
  transform: translateY(9px) rotate(45deg);
}
.site-header.is-open .menu-toggle span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}
.site-header.is-open .menu-toggle span:nth-child(3) {
  transform: translateY(-9px) rotate(-45deg);
}

/* ── Mobile Drawer ── */
.mobile-drawer {
  display: none;
  position: fixed;
  top: var(--nav-height);
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--color-mobile-drawer);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  z-index: 999;
  transform: translateX(-100%);
  transition: transform var(--duration-slow) var(--ease-default);
  overflow-y: auto;
}

.mobile-drawer[aria-hidden="false"] {
  transform: translateX(0);
}

.mobile-nav {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  padding: var(--space-8) var(--space-6);
}

.mobile-link {
  font-size: var(--text-heading);
  font-weight: 700;
  color: var(--color-text-base);
  padding: var(--space-4) 0;
  border-bottom: 1px solid var(--color-border-subtle);
  transition: color var(--duration-base);
}
.mobile-link:hover {
  color: var(--color-blue);
}

.mobile-cta-btn {
  display: block;
  margin-top: var(--space-6);
  padding: var(--space-4) var(--space-6);
  text-align: center;
  background: var(--gradient-brand);
  color: #0C0F19;
  font-weight: 700;
  font-size: var(--text-base);
  border-radius: var(--radius-lg);
  font-family: var(--font-display);
}