.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 0 var(--space-md);
  border-bottom: 1px solid transparent;
  transition: background-color 0.25s ease, border-color 0.25s ease, backdrop-filter 0.25s ease;
}

.nav.nav--scrolled {
  background-color: rgba(11, 18, 16, 0.88);
  backdrop-filter: blur(18px) saturate(1.4);
  -webkit-backdrop-filter: blur(18px) saturate(1.4);
  border-bottom-color: rgba(42, 157, 143, 0.18);
}

:root[data-theme="light"] .nav.nav--scrolled {
  background-color: rgba(250, 251, 250, 0.85);
  border-bottom-color: rgba(31, 122, 110, 0.18);
}

.nav__inner {
  max-width: 1200px;
  margin: 0 auto;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
}

.nav__logo {
  font-family: 'Playfair Display', serif;
  font-size: 1.4rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  flex-shrink: 0;
}

.nav__logo-drop {
  color: var(--drop-blue);
}

.nav__logo-img {
  height: 44px;
  width: auto;
  display: block;
}

/* Theme-aware logo swap: white-text logo on dark, dark-text logo on light */
.nav__logo-img--light {
  display: none;
}

:root[data-theme="light"] .nav__logo-img--dark {
  display: none;
}

:root[data-theme="light"] .nav__logo-img--light {
  display: block;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.nav__link {
  position: relative;
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 400;
  transition: color 0.2s ease;
  white-space: nowrap;
}

.nav__link::after {
  content: '';
  position: absolute;
  left: 0;
  right: 100%;
  bottom: -6px;
  height: 2px;
  background: linear-gradient(90deg, var(--green-primary), var(--teal));
  border-radius: 2px;
  transition: right 0.25s ease-out;
}

.nav__link:hover::after,
.nav__link--active::after {
  right: 0;
}

.nav__link:hover,
.nav__link--active {
  color: var(--text-primary);
}

@media (prefers-reduced-motion: reduce) {
  .nav__link::after { transition: none; }
}

.nav__lang-toggle {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  color: var(--text-muted);
  font-size: 0.82rem;
}

.nav__lang {
  color: var(--text-muted);
  transition: color 0.2s ease;
}

.nav__lang:hover {
  color: var(--text-secondary);
}

.nav__lang--active {
  color: var(--text-primary);
  font-weight: 500;
}

.nav__lang-select {
  display: flex;
  align-items: center;
}

/* Theme toggle */
.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 1px solid var(--bg-border);
  background-color: transparent;
  color: var(--text-secondary);
  flex-shrink: 0;
  transition: border-color 0.2s ease, color 0.2s ease, background-color 0.2s ease;
}

.theme-toggle:hover {
  border-color: var(--green-primary);
  color: var(--text-primary);
}

.theme-toggle__icon {
  width: 18px;
  height: 18px;
}

.theme-toggle__icon--sun { display: none; }
.theme-toggle__icon--moon { display: block; }

:root[data-theme="light"] .theme-toggle__icon--sun { display: block; }
:root[data-theme="light"] .theme-toggle__icon--moon { display: none; }

/* Hamburger */
.nav__hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 4px;
  flex-shrink: 0;
}

.nav__hamburger span {
  display: block;
  width: 22px;
  height: 1.5px;
  background-color: var(--text-secondary);
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.nav__hamburger[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(6.5px) rotate(45deg);
}

.nav__hamburger[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.nav__hamburger[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-6.5px) rotate(-45deg);
}

/* Mobile nav */
@media (max-width: 899px) {
  .nav__hamburger {
    display: flex;
  }

  .nav__links {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    background-color: var(--bg-surface);
    border-bottom: 1px solid var(--bg-border);
    flex-direction: column;
    align-items: flex-start;
    padding: var(--space-md);
    gap: var(--space-sm);
    transform: translateY(calc(-100% - 64px));
    transition: transform 0.25s ease;
    z-index: 99;
  }

  .nav__links.nav__links--open {
    transform: translateY(0);
  }

  .nav__link {
    font-size: 1rem;
    padding: 0.4rem 0;
    width: 100%;
    border-bottom: 1px solid var(--bg-border);
  }

  .nav__lang-toggle {
    padding: 0.4rem 0;
  }
}