/* nav.css — Top navigation */

.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: var(--z-nav);
  height: var(--nav-h);
  display: flex;
  align-items: center;
  background: var(--ink);
  border-bottom: 1px solid transparent;
  transition:
    background var(--dur-base) var(--ease),
    border-color var(--dur-base) var(--ease);
}

.nav.scrolled {
  background: var(--surface-1);
  border-bottom-color: var(--paper-faint);
}

[data-theme='light'] .nav           { background: var(--ink); }
[data-theme='light'] .nav.scrolled  { background: var(--surface-1); }

/* ── inner ── */
.nav__inner {
  width: 100%;
  max-width: var(--max-outer);
  margin-inline: auto;
  padding-inline: var(--side-pad);
  display: flex;
  align-items: center;
  gap: var(--sp-8);
}

/* ── brand ── */
.nav__brand {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.875rem;
  letter-spacing: 0.05em;
  color: var(--paper);
  flex-shrink: 0;
  margin-right: auto;
}

.nav__brand-logo {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
}

.nav__wordmark {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.85rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.nav__wordmark span {
  color: var(--accent);
}

/* ── grouped links ── */
.nav__links {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
}

/* ── group dropdown trigger ── */
.nav__group {
  position: relative;
}

.nav__group-btn {
  display: flex;
  align-items: center;
  gap: 5px;
  font-family: var(--font-mono);
  font-size: var(--type-micro);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--paper-dim);
  padding: var(--sp-2) var(--sp-3);
  border-radius: var(--r-sm);
  transition:
    color var(--dur-base) var(--ease),
    background var(--dur-base) var(--ease);
  white-space: nowrap;
}

.nav__group-btn:hover,
.nav__group.is-active .nav__group-btn {
  color: var(--paper);
}

.nav__group.is-open .nav__group-btn {
  color: var(--paper);
  background: var(--paper-faint);
}

.nav__chevron {
  transition: transform var(--dur-base) var(--ease);
  flex-shrink: 0;
}

.nav__group.is-open .nav__chevron {
  transform: rotate(180deg);
}

/* active dot */
.nav__group.is-active .nav__group-btn::before {
  content: '';
  position: absolute;
  left: 4px; top: 50%;
  transform: translateY(-50%);
  width: 4px; height: 4px;
  background: var(--accent);
  border-radius: 50%;
}

/* ── dropdown panel ── */
.nav__drop {
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  min-width: 180px;
  background: var(--surface-1);
  border: 1px solid var(--paper-faint);
  border-radius: var(--r-md);
  padding: var(--sp-2);
  display: flex;
  flex-direction: column;
  gap: 2px;

  /* hidden state */
  opacity: 0;
  transform: translateY(-6px);
  pointer-events: none;
  transition:
    opacity var(--dur-base) var(--ease),
    transform var(--dur-base) var(--ease);
}

.nav__group.is-open .nav__drop {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.nav__drop-item {
  display: block;
  padding: var(--sp-2) var(--sp-3);
  font-family: var(--font-mono);
  font-size: var(--type-micro);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--paper-dim);
  border-radius: var(--r-sm);
  transition: color var(--dur-base) var(--ease), background var(--dur-base) var(--ease);
  white-space: nowrap;
}

.nav__drop-item:hover {
  color: var(--paper);
  background: var(--paper-faint);
}

.nav__drop-item.is-active {
  color: var(--accent);
}

/* ── right actions ── */
.nav__actions {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  flex-shrink: 0;
}

.nav__cta {
  font-size: 0.75rem;
  padding: 8px 16px;
  white-space: nowrap;
}

.nav__theme {
  width: 36px; height: 36px;
  display: grid; place-items: center;
  border: 1px solid var(--paper-faint);
  border-radius: var(--r-sm);
  color: var(--paper);
  flex-shrink: 0;
  transition: border-color var(--dur-base) var(--ease);
}

.nav__theme:hover { border-color: var(--paper); }

/* ── burger — hidden on desktop ── */
.nav__burger {
  width: 36px; height: 36px;
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 4px;
  border: 1px solid var(--paper-faint);
  border-radius: var(--r-sm);
  flex-shrink: 0;
}

.nav__burger span {
  display: block;
  width: 16px; height: 2px;
  background: var(--paper);
  transition: transform var(--dur-base) var(--ease), opacity var(--dur-base) var(--ease);
}

.nav__burger.is-open span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav__burger.is-open span:nth-child(2) { opacity: 0; }
.nav__burger.is-open span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* ── responsive: burger at ≤1100px ── */
@media (max-width: 1100px) {
  .nav__links  { display: none; }
  .nav__cta    { display: none; }
  .nav__burger { display: flex; }
}