/* ==========================================================================
   LAYOUT — header / navigation / mobile menu / footer.
   ========================================================================== */

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

.site-header.is-scrolled {
  background-color: color-mix(in srgb, var(--color-bg) 78%, transparent);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  border-bottom-color: var(--color-line);
}

.site-header.is-hidden {
  transform: translateY(-100%);
}

.site-header__inner {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--gutter);
}

.brand {
  font-family: var(--font-mono);
  font-size: var(--fs-sm);
  font-weight: 500;
  letter-spacing: 0.06em;
}

.brand sup {
  color: var(--color-accent-ink);
  font-size: 0.72em; /* 0.6em rendered at 9px — below legible */
  margin-left: 0.15em;
}

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

/* ---- Desktop nav -------------------------------------------------------- */
.site-nav {
  display: none;
}

@media (min-width: 768px) {
  .site-nav {
    display: flex;
    gap: var(--sp-6);
  }
}

.site-nav a {
  position: relative;
  font-family: var(--font-mono);
  font-size: var(--fs-2xs);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: var(--track-caps);
  color: var(--color-text-muted);
  transition: color var(--dur-micro) ease;
}

.site-nav a::before {
  content: "";
  position: absolute;
  left: -0.85em;
  top: 50%;
  translate: 0 -50%;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--color-accent);
  opacity: 0;
  transition: opacity var(--dur-micro) ease;
}

.site-nav a:hover,
.site-nav a.is-active {
  color: var(--color-text);
}

.site-nav a.is-active::before {
  opacity: 1;
}

/* ---- Theme toggle -------------------------------------------------------- */
.theme-toggle {
  width: 2.5rem;
  height: 2.5rem;
  display: grid;
  place-items: center;
  border: 1px solid var(--color-line-strong);
  border-radius: 50%;
  color: var(--color-text);
  transition:
    border-color var(--dur-micro) ease,
    transform var(--dur-micro) var(--ease-adjust);
}

.theme-toggle:hover {
  border-color: var(--color-text);
  transform: rotate(15deg);
}

.theme-toggle svg {
  width: 1rem;
  height: 1rem;
  grid-area: 1 / 1; /* stacked — theme.js cross-morphs them with Anime.js */
}

/* Resting states (JS animates between them; this is also the no-JS truth) */
.theme-toggle .icon--sun {
  opacity: 0;
  transform: scale(0.4) rotate(90deg);
}

[data-theme="dark"] .theme-toggle .icon--sun {
  opacity: 1;
  transform: none;
}

[data-theme="dark"] .theme-toggle .icon--moon {
  opacity: 0;
  transform: scale(0.4) rotate(-90deg);
}

/* ---- Intro initial states (released when html gets .intro-done) ---------- */
@media (prefers-reduced-motion: no-preference) {
  .js:not(.intro-done) .brand,
  .js:not(.intro-done) .site-nav a,
  .js:not(.intro-done) .theme-toggle,
  .js:not(.intro-done) .nav-burger {
    opacity: 0;
  }
}

/* ---- Burger (mobile) ----------------------------------------------------- */
.nav-burger {
  width: 2.75rem;
  height: 2.75rem;
  display: grid;
  place-items: center;
}

@media (min-width: 768px) {
  .nav-burger {
    display: none;
  }
}

.nav-burger__box {
  display: flex;
  flex-direction: column;
  gap: 7px;
}

.nav-burger span {
  display: block;
  width: 22px;
  height: 1.5px;
  background: var(--color-text);
  transition: transform var(--dur-micro) var(--ease-adjust);
}

.nav-burger.is-open span:nth-child(1) {
  transform: translateY(4.25px) rotate(45deg);
}

.nav-burger.is-open span:nth-child(2) {
  transform: translateY(-4.25px) rotate(-45deg);
}

/* ---- Mobile menu overlay -------------------------------------------------- */
.menu {
  position: fixed;
  inset: 0;
  z-index: var(--z-menu);
  background: var(--color-bg);
  padding: calc(var(--header-h) + var(--sp-6)) var(--container-pad) var(--sp-6);
  display: flex;
  flex-direction: column;
  visibility: hidden;
  opacity: 0;
  /* Short phones must still reach the last link; never trap the scroll */
  overflow-y: auto;
  overscroll-behavior: contain;
  transition:
    opacity var(--dur-fast) ease,
    visibility 0s linear var(--dur-fast);
}

.menu.is-open {
  visibility: visible;
  opacity: 1;
  transition: opacity var(--dur-fast) ease;
}

@media (min-width: 768px) {
  .menu {
    display: none;
  }
}

body.menu-open {
  overflow: hidden;
}

.menu__list {
  display: flex;
  flex-direction: column;
  gap: var(--sp-4);
}

.menu__list li {
  opacity: 0;
  transform: translateY(20px);
  transition:
    opacity var(--dur-base) var(--ease-enter),
    transform var(--dur-base) var(--ease-enter);
}

.menu.is-open .menu__list li {
  opacity: 1;
  transform: none;
}

.menu.is-open .menu__list li:nth-child(1) { transition-delay: 0.1s; }
.menu.is-open .menu__list li:nth-child(2) { transition-delay: 0.16s; }
.menu.is-open .menu__list li:nth-child(3) { transition-delay: 0.22s; }
.menu.is-open .menu__list li:nth-child(4) { transition-delay: 0.28s; }
.menu.is-open .menu__list li:nth-child(5) { transition-delay: 0.34s; }

/* The primary navigation on a phone — sized like it matters */
.menu__link {
  display: flex;
  align-items: baseline;
  gap: var(--sp-4);
  padding-block: 0.25em;
  min-height: 56px;
  font-family: var(--font-display);
  font-size: clamp(2rem, 10vw, 3.5rem);
  font-weight: 600;
  text-transform: uppercase;
  line-height: 1.1;
  letter-spacing: var(--track-tight);
}

.menu__meta a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
}

.menu__link .menu__idx {
  font-family: var(--font-mono);
  font-size: var(--fs-2xs);
  font-weight: 500;
  color: var(--color-accent-ink);
  letter-spacing: var(--track-caps);
}

.menu__meta {
  margin-top: auto;
  padding-top: var(--sp-5);
  border-top: 1px solid var(--color-line);
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
  color: var(--color-text-muted);
}

.menu__meta a {
  color: var(--color-text);
}

/* ---- Footer ---------------------------------------------------------------- */
.site-footer {
  border-top: 1px solid var(--color-line);
  padding-block: var(--sp-7) var(--sp-6);
}

.site-footer__top {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--sp-6) var(--gutter);
}

.site-footer__name {
  font-family: var(--font-display);
  font-size: clamp(1.15rem, 2vw, 1.5rem);
  font-weight: 500;
  letter-spacing: var(--track-tight);
}

.site-footer__role {
  margin-top: var(--sp-1);
  font-family: var(--font-mono);
  font-size: var(--fs-2xs);
  text-transform: uppercase;
  letter-spacing: var(--track-caps);
  color: var(--color-text-muted);
}

.site-footer__links {
  display: flex;
  flex-direction: column;
  gap: var(--sp-2);
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
}

.site-footer__links .link:hover {
  color: var(--color-accent-ink);
}

/* Back to top — two stacked arrows, swapped by Anime.js on hover */
.to-top {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-3);
  padding: 0.6em 0;
  font-family: var(--font-mono);
  font-size: var(--fs-2xs);
  text-transform: uppercase;
  letter-spacing: var(--track-caps);
  color: var(--color-text-muted);
  transition: color var(--dur-micro) ease;
}

.to-top:hover {
  color: var(--color-text);
}

.to-top__arrows {
  position: relative;
  display: block;
  width: 1.5rem;
  height: 1.5rem;
  overflow: clip;
  border: 1px solid var(--color-line-strong);
  border-radius: 50%;
  transition: border-color var(--dur-micro) ease;
}

.to-top:hover .to-top__arrows {
  border-color: var(--color-accent);
}

.to-top__arrow {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  line-height: 1;
  color: var(--color-accent-ink);
}

/* The second arrow waits below, ready to take the first one's place */
.to-top__arrow:last-child {
  transform: translateY(100%);
}

.site-footer__bottom {
  margin-top: var(--sp-7);
  padding-top: var(--sp-4);
  border-top: 1px solid var(--color-line);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-2) var(--sp-4);
  font-family: var(--font-mono);
  font-size: var(--fs-2xs);
  letter-spacing: 0.04em;
  color: var(--color-text-muted);
}