/* ============================================================
   NAV, sticky header + mobile drawer
   ============================================================ */

.nav {
  /* Centred glass pill, floating clear of the page edge */
  position: fixed;
  top: clamp(14px, 2.2vh, 26px);
  left: 50%;
  transform: translateX(-50%);
  z-index: 90;
  height: auto;
  display: flex;
  align-items: center;
  gap: 0;
  padding: 8px 8px 8px clamp(18px, 1.8vw, 24px);
  border-radius: 999px;
  width: max-content;
  max-width: calc(100vw - 2 * var(--gutter));
  background: rgba(248, 246, 242, 0.62);
  border: 1px solid rgba(255, 255, 255, 0.6);
  box-shadow: 0 12px 40px -14px rgba(11,11,12,.22), inset 0 1px 0 rgba(255,255,255,.85);
  backdrop-filter: blur(22px) saturate(1.7);
  -webkit-backdrop-filter: blur(22px) saturate(1.7);
  opacity: 1;
  visibility: visible;
  transition:
    background var(--dur) var(--ease),
    border-color var(--dur) var(--ease),
    backdrop-filter var(--dur) var(--ease);
  border-bottom: 1px solid transparent;
}
.nav.is-stuck-unused {
  background: rgba(250,249,247,0.82);
  backdrop-filter: blur(18px) saturate(1.4);
  -webkit-backdrop-filter: blur(18px) saturate(1.4);
  border-bottom-color: var(--line);
}
.nav.is-dark-unused {
  background: rgba(11,11,12,0.74);
  border-bottom-color: var(--line-dark);
}

.nav { transition-property: opacity, transform; }

.nav__inner {
  width: max-content;
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: clamp(1.2rem, 2.4vw, 2.4rem);
}

.nav__brand { display: inline-flex; align-items: center; flex: none; }
.nav__brand .logo__img { height: 26px; transition: filter var(--dur) var(--ease); }


.nav__links {
  display: flex;
  align-items: center;
  flex-wrap: nowrap;
  padding-left: clamp(1rem, 2vw, 1.8rem);
  border-left: 1px solid rgba(20,16,11,.10);
  gap: clamp(0.85rem, 1.6vw, 1.6rem);
}
.nav__link {
  white-space: nowrap;
  font-size: var(--fs-sm);
  color: var(--text-2);
  position: relative;
  padding-block: 4px;
}
.nav__link::after {
  content: "";
  position: absolute;
  left: 0; bottom: 0;
  width: 0; height: 1px;
  background: currentColor;
  transition: width var(--dur) var(--ease-out);
}
.nav__link:hover { color: var(--text); }
.nav__link:hover::after { width: 100%; }
.nav.is-dark .nav__link { color: var(--on-dark-2); }
.nav.is-dark .nav__link:hover { color: var(--on-dark); }

.nav__cta {
  margin-left: clamp(1rem, 2vw, 1.8rem);
  flex: none;
  height: 40px;
  padding: 0 20px;
  font-size: 0.9375rem;
}
.nav.is-dark .nav__cta.btn--primary {
  --btn-bg: var(--paper); --btn-fg: var(--ink); --btn-bd: var(--paper);
}

/* ---------- Burger ---------- */
.nav__burger {
  display: none;
  margin-left: auto;
  width: 40px; height: 40px;
  border-radius: 999px;
  border: 1px solid var(--line-strong);
  place-items: center;
  flex: none;
}
.nav.is-dark .nav__burger { border-color: var(--line-dark-2); }
.nav__burger span {
  display: block;
  width: 16px; height: 1.5px;
  background: currentColor;
  border-radius: 2px;
  transition: transform var(--dur) var(--ease-out), opacity var(--dur-fast) var(--ease);
}
.nav__burger span + span { margin-top: 4px; }
.nav.is-dark .nav__burger { color: var(--on-dark); }
body.is-menu-open .nav__burger span:nth-child(1) { transform: translateY(5.5px) rotate(45deg); }
body.is-menu-open .nav__burger span:nth-child(2) { opacity: 0; }
body.is-menu-open .nav__burger span:nth-child(3) { transform: translateY(-5.5px) rotate(-45deg); }

/* ---------- Mobile drawer ---------- */
.drawer {
  position: fixed;
  inset: 0;
  z-index: 85;
  background: var(--paper);
  padding: calc(var(--nav-h) + 28px) var(--gutter) 40px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-8px);
  transition:
    opacity var(--dur) var(--ease),
    transform var(--dur) var(--ease-out),
    visibility var(--dur);
}
body.is-menu-open .drawer { opacity: 1; visibility: visible; transform: none; }

.drawer__link {
  font-family: var(--font-display);
  font-size: clamp(1.9rem, 8vw, 2.6rem);
  letter-spacing: var(--ls-head);
  font-weight: 500;
  padding-block: 14px;
  border-bottom: 1px solid var(--line);
  display: flex;
  align-items: baseline;
  gap: 14px;
}
.drawer__idx {
  font-family: var(--font-mono);
  font-size: var(--fs-label);
  letter-spacing: 0.12em;
  color: var(--bronze);
}
.drawer__foot { margin-top: auto; padding-top: 32px; display: grid; gap: 14px; }
.drawer__meta {
  font-family: var(--font-mono);
  font-size: var(--fs-label);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-3);
}

@media (max-width: 900px) {
  .nav__links { display: none; }
  .nav__cta   { display: none; }
  .nav__burger { display: grid; }
}
@media (min-width: 901px) {
  .drawer { display: none; }
}