#navbar {
  position: fixed;
  top: 0;
  width: 100%;
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border-bottom: var(--glass-rim);
  z-index: 1000;
  transition: all var(--transition-smooth);
}

#navbar::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image: var(--glass-noise);
  opacity: 0.03;
  pointer-events: none;
  z-index: -1;
}

#navbar.scrolled {
  background: rgba(0, 0, 0, 0.95);
  box-shadow: var(--shadow-md);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-md) var(--space-md);
  max-width: var(--max-width);
  margin: 0 auto;
}

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text);
  text-decoration: none;
  transition: transform var(--transition-fast);
  /* A11Y Touch Target */
  display: inline-flex;
  align-items: center;
  min-height: var(--touch-target);
}

.logo:hover {
  transform: scale(1.05);
}

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

.nav-menu {
  /* Mobile First - Liquid Glass */
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100vh;
  background: rgba(10, 10, 10, 0.9);
  backdrop-filter: blur(40px) saturate(220%);
  border-left: 1px solid rgba(255, 255, 255, 0.1); /* Subtle sheen edge */
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: var(--space-2xl);
  gap: var(--space-xl);
  transform: translateY(-100%);
  opacity: 0;
  visibility: hidden;
  transition: transform 0.6s cubic-bezier(0.85, 0, 0.15, 1), 
              opacity 0.4s ease, 
              visibility 0.4s;
  border-bottom: none;
  display: flex;
  list-style: none;
  z-index: -1;
}

.nav-menu.active {
  transform: translateY(0);
  opacity: 1;
  visibility: visible;
}

.nav-menu::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: radial-gradient(circle at center, var(--accent-glow) 0%, transparent 70%);
  opacity: 0.15;
  pointer-events: none;
}

.nav-menu::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image: var(--glass-noise);
  opacity: 0.05;
  pointer-events: none;
  z-index: -1;
}

.nav-link {
  color: var(--text);
  text-decoration: none;
  font-weight: 600;
  font-size: 1.5rem;
  padding: var(--space-sm) var(--space-lg);
  position: relative;
  transition: all var(--transition-smooth);
  /* A11Y Touch Target */
  display: flex;
  align-items: center;
  min-height: var(--touch-target);
  width: 100%;
  justify-content: center;
  transform: translate(var(--mag-x, 0px), var(--mag-y, 0px));
}

.nav-menu.active .nav-link {
  animation: slideInUp 0.5s cubic-bezier(0.4, 0, 0.2, 1) forwards;
  opacity: 0;
}

.nav-menu.active li:nth-child(1) .nav-link { animation-delay: 0.1s; }
.nav-menu.active li:nth-child(2) .nav-link { animation-delay: 0.2s; }
.nav-menu.active li:nth-child(3) .nav-link { animation-delay: 0.3s; }
.nav-menu.active li:nth-child(4) .nav-link { animation-delay: 0.4s; }

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

.nav-link.active,
.nav-link:hover {
  color: white;
}

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

.hamburger {
  display: flex; /* Mobile First */
  flex-direction: column;
  cursor: pointer;
  gap: 0.3125rem;
  padding: var(--space-sm);
  background: transparent;
  border: none;
  /* A11Y Touch Target */
  min-width: var(--touch-target);
  min-height: var(--touch-target);
  justify-content: center;
  align-items: center;
}

.hamburger span {
  width: 1.5625rem;
  height: 0.1875rem;
  background: var(--text);
  border-radius: 0.125rem;
  transition: all var(--transition-smooth);
}

.hamburger.active span:nth-child(1) {
  transform: translateY(0.5625rem) rotate(45deg);
}

.hamburger.active span:nth-child(2) {
  opacity: 0;
  transform: translateX(-20px);
}

.hamburger.active span:nth-child(3) {
  transform: translateY(-0.5625rem) rotate(-45deg);
}

/* Tablet & Desktop */
@media (min-width: 48rem) {
  .hamburger {
    display: none;
  }

  .nav-menu {
    position: static;
    height: auto;
    flex-direction: row;
    background: transparent;
    backdrop-filter: none;
    padding: 0;
    transform: none;
    opacity: 1;
    visibility: visible;
    border: none;
    width: auto;
    gap: var(--space-xl);
    z-index: 1;
  }

  .nav-menu::before { display: none; }

  .nav-link {
    font-size: 0.95rem;
    font-weight: 500;
    width: auto;
    color: var(--muted);
  }

  .nav-menu.active .nav-link {
    animation: none;
    opacity: 1;
  }
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 0.1875rem;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  z-index: 9999;
  transition: width 0.1s ease-out;
  box-shadow: 0 0 0.625rem var(--accent-glow);
}