/* ==========================================================================
   NAVBAR
   ========================================================================== */

.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-h);
  z-index: var(--z-nav);
  display: flex;
  align-items: center;
  padding: 0 var(--gutter);
  background: linear-gradient(to bottom, rgba(2, 9, 18, 0.32), transparent);
  transition: background 0.5s var(--ease-soft), backdrop-filter 0.5s var(--ease-soft), box-shadow 0.5s var(--ease-soft);
}

.navbar.is-scrolled {
  background: rgba(4, 13, 24, 0.68);
  backdrop-filter: blur(18px) saturate(150%);
  -webkit-backdrop-filter: blur(18px) saturate(150%);
  box-shadow: 0 1px 0 var(--c-line), 0 16px 40px rgba(0,0,0,0.3);
}

.navbar__inner {
  width: 100%;
  max-width: var(--content-max);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.navbar__brand {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-family: var(--font-display);
  font-size: 1.18rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--c-foam);
  transition: opacity 0.3s var(--ease-out);
}
.navbar__brand:hover { opacity: 0.8; }

.navbar__brand-icon {
  width: 26px;
  height: 26px;
  flex-shrink: 0;
  color: var(--c-bio-cyan);
  transition: transform 0.4s var(--ease-out);
}
.navbar__brand:hover .navbar__brand-icon { transform: translateY(-1px) scale(1.08); }

.navbar__links {
  display: flex;
  align-items: center;
  gap: var(--sp-5);
}

.navbar__link {
  position: relative;
  font-size: 0.9rem;
  font-weight: 500;
  letter-spacing: 0.01em;
  color: var(--c-foam-dim);
  padding: 0.35rem 0.1rem;
  transition: color 0.3s var(--ease-out);
}

.navbar__link::after {
  content: '';
  position: absolute;
  left: 0; bottom: -3px;
  width: 0%;
  height: 2px;
  border-radius: 2px;
  background: var(--c-bio-cyan);
  transition: width 0.35s var(--ease-out), box-shadow 0.35s var(--ease-out);
}

.navbar__link:hover { color: var(--c-foam); }
.navbar__link:hover::after { width: 100%; }

.navbar__link.is-active {
  color: var(--c-bio-cyan-soft);
}
.navbar__link.is-active::after {
  width: 100%;
  box-shadow: 0 0 10px rgba(62, 198, 224, 0.7);
}

.navbar__actions {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
}

.navbar__menu-btn {
  display: none;
  width: 42px;
  height: 42px;
  border-radius: var(--radius-sm);
  align-items: center;
  justify-content: center;
  color: var(--c-foam);
  background: rgba(255,255,255,0.06);
  border: 1px solid var(--c-line);
  transition: background 0.3s var(--ease-out), border-color 0.3s var(--ease-out);
}
.navbar__menu-btn:hover { background: rgba(255,255,255,0.1); border-color: var(--c-line-strong); }

.navbar__menu-btn svg { width: 20px; height: 20px; }

/* Mobile drawer */
.nav-drawer {
  position: fixed;
  inset: 0;
  z-index: var(--z-overlay);
  background: rgba(2, 9, 18, 0.97);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--sp-4);
  opacity: 0;
  visibility: hidden;
  transform: scale(1.02);
  transition: opacity 0.45s var(--ease-soft), visibility 0.45s var(--ease-soft), transform 0.45s var(--ease-soft);
}

.nav-drawer.is-open { opacity: 1; visibility: visible; transform: scale(1); }

.nav-drawer__link {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 6vw, 2.4rem);
  color: var(--c-foam-dim);
  opacity: 0;
  transform: translateY(14px);
  transition: color 0.3s var(--ease-out), transform 0.3s var(--ease-out), opacity 0.45s var(--ease-out);
  transition-delay: 0.08s;
}
.nav-drawer.is-open .nav-drawer__link {
  opacity: 1;
  transform: translateY(0);
}
.nav-drawer.is-open .nav-drawer__link:nth-child(2) { transition-delay: 0.12s; }
.nav-drawer.is-open .nav-drawer__link:nth-child(3) { transition-delay: 0.16s; }
.nav-drawer.is-open .nav-drawer__link:nth-child(4) { transition-delay: 0.2s; }
.nav-drawer.is-open .nav-drawer__link:nth-child(5) { transition-delay: 0.24s; }
.nav-drawer.is-open .nav-drawer__link:nth-child(6) { transition-delay: 0.28s; }
.nav-drawer__link:hover, .nav-drawer__link.is-active { color: var(--c-bio-cyan-soft); transform: translateX(6px); }

.nav-drawer__close {
  position: absolute;
  top: var(--sp-4);
  right: var(--gutter);
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--c-foam);
  background: rgba(255,255,255,0.06);
  border-radius: var(--radius-sm);
  transition: background 0.3s var(--ease-out), transform 0.3s var(--ease-out);
}
.nav-drawer__close:hover { background: rgba(255,255,255,0.12); transform: rotate(90deg); }

@media (max-width: 880px) {
  .navbar__links { display: none; }
  .navbar__menu-btn { display: flex; }
}