/* ==========================================================================
   Header — transparent over the hero, an ink bar once scrolled
   ========================================================================== */

.header {
  position: fixed;
  inset-block-start: 0;
  inset-inline: 0;
  z-index: var(--z-header);
  border-bottom: 1px solid transparent;
  transition:
    background-color var(--dur-mid) var(--ease),
    border-color var(--dur-mid) var(--ease);
}

.header.is-stuck {
  background-color: rgba(7, 18, 32, 0.9);
  border-bottom-color: var(--rule-on-ink);
  backdrop-filter: blur(16px) saturate(150%);
  -webkit-backdrop-filter: blur(16px) saturate(150%);
}

.header__inner {
  display: flex;
  align-items: center;
  gap: var(--space-6);
  min-height: 5.75rem;
  transition: min-height var(--dur-mid) var(--ease);
}

.header.is-stuck .header__inner { min-height: 4.5rem; }

/* ---- Brand lockup: mark beside wordmark, as in the reference ------------- */

.brand { display: inline-flex; align-items: center; gap: 0.8rem; flex: none; }

.brand__mark {
  height: 3rem;
  width: auto;
  transition: height var(--dur-mid) var(--ease);
}

.brand__wordmark {
  height: 1.9rem;
  width: auto;
  transition: height var(--dur-mid) var(--ease);
}

.header.is-stuck .brand__mark { height: 2.4rem; }
.header.is-stuck .brand__wordmark { height: 1.55rem; }

/* ---- Navigation ----------------------------------------------------------- */

.nav { margin-inline-start: auto; }

.nav__list {
  display: flex;
  align-items: center;
  gap: clamp(0.6rem, 0.1rem + 1.2vw, 1.5rem);
}

.nav__link {
  position: relative;
  display: block;
  padding: 0.5rem 0.15rem;
  color: var(--ink-fg-soft);
  font-size: var(--fs-sm);
  font-weight: 500;
}

.nav__link::after {
  content: "";
  position: absolute;
  inset-inline: 0;
  inset-block-end: 0;
  height: 1px;
  background-color: var(--accent);
  scale: 0 1;
  transition: scale var(--dur-mid) var(--ease);
}

.nav__link:hover { color: var(--ink-fg); }
.nav__link:hover::after,
.nav__link.is-active::after { scale: 1 1; }
.nav__link.is-active { color: var(--ink-fg); }

.header__actions { display: flex; align-items: center; gap: 0.75rem; flex: none; }
.header__actions .btn { padding: 0.75rem 1.4rem; font-size: var(--fs-xs); }

/* ---- Hamburger ------------------------------------------------------------- */

.nav-toggle {
  display: none;
  place-items: center;
  width: 2.75rem;
  height: 2.75rem;
  color: var(--ink-fg);
}

.nav-toggle__bars {
  position: relative;
  width: 1.35rem;
  height: 1px;
  background-color: currentColor;
  transition: background-color var(--dur-fast) var(--ease);
}

.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  inset-inline: 0;
  height: 1px;
  background-color: currentColor;
  transition: transform var(--dur-mid) var(--ease);
}

.nav-toggle__bars::before { top: -7px; }
.nav-toggle__bars::after { top: 7px; }

.nav-toggle[aria-expanded="true"] .nav-toggle__bars { background-color: transparent; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after { transform: translateY(-7px) rotate(-45deg); }

/* ---- Drawer ----------------------------------------------------------------- */

.drawer {
  position: fixed;
  inset: 0;
  z-index: var(--z-drawer);
  display: grid;
  grid-template-rows: auto 1fr;
  background-color: var(--ink-950);
  visibility: hidden;
  opacity: 0;
  transition: opacity var(--dur-mid) var(--ease), visibility var(--dur-mid) var(--ease);
}

.drawer.is-open { visibility: visible; opacity: 1; }

.drawer__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 5.75rem;
  border-bottom: 1px solid var(--rule-on-ink);
}

.drawer__body {
  display: flex;
  flex-direction: column;
  gap: var(--space-8);
  padding-block: var(--space-8);
  overflow-y: auto;
}

.drawer__link {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  padding-block: 0.85rem;
  border-bottom: 1px solid var(--rule-on-ink-soft);
  color: var(--ink-fg);
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 600;

  /* staggered entrance, index supplied by --i in the markup */
  opacity: 0;
  transform: translateX(1.5rem);
}

.drawer.is-open .drawer__link {
  animation: drawer-item var(--dur-slow) var(--ease) forwards;
  animation-delay: calc(60ms + var(--i, 0) * 45ms);
}

.drawer__link::before {
  content: counter(drawer-item, decimal-leading-zero);
  counter-increment: drawer-item;
  font-family: var(--font-text);
  font-size: var(--fs-xs);
  font-weight: 500;
  color: var(--ink-fg-dim);
}

.drawer__list { counter-reset: drawer-item; }
.drawer__link.is-active { color: var(--accent); }

.drawer__actions { display: flex; flex-direction: column; gap: var(--space-3); }

.drawer__contact {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  padding-top: var(--space-6);
  border-top: 1px solid var(--rule-on-ink);
  color: var(--ink-fg-dim);
  font-size: var(--fs-sm);
}

.drawer__contact a { color: var(--ink-fg); font-weight: 600; }
.drawer__contact a:hover { color: var(--accent); }