/* ============================================================================
   ATOMIC LAB — SHELL: navigation, command palette, footer
   ========================================================================== */

/* ---------------------------------------------------------------------------
   NAV
   ------------------------------------------------------------------------- */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 200;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  transition: background var(--d-3) var(--e-out), border-color var(--d-3) var(--e-out), backdrop-filter var(--d-3);
  border-bottom: 1px solid transparent;
}
.nav.is-stuck {
  background: rgba(5, 8, 14, 0.78);
  border-bottom-color: var(--edge);
  backdrop-filter: blur(18px) saturate(1.4);
  -webkit-backdrop-filter: blur(18px) saturate(1.4);
}
/* Scroll progress hairline */
.nav__progress {
  position: absolute; bottom: -1px; left: 0; height: 2px;
  width: var(--p, 0%);
  background: linear-gradient(90deg, var(--beam), var(--pulse));
  box-shadow: 0 0 10px rgba(89,230,255,0.6);
  transition: width 90ms linear;
  pointer-events: none;
}

.nav__inner {
  width: 100%; max-width: var(--maxw-wide);
  margin-inline: auto; padding-inline: var(--gutter);
  display: flex; align-items: center; gap: var(--s-5);
}

/* --- Brand --- */
.brand { display: inline-flex; align-items: center; gap: 0.7rem; flex: none; }
.brand__mark { width: 30px; height: 30px; flex: none; overflow: visible; }
.brand__mark .nuc { fill: var(--beam); filter: drop-shadow(0 0 5px var(--beam)); }
.brand__mark .orb { fill: none; stroke: rgba(255,255,255,0.28); stroke-width: 1; }
.brand__mark .e   { fill: #fff; filter: drop-shadow(0 0 4px var(--beam)); }
.brand__mark .spin1 { transform-origin: 24px 24px; animation: spin 7s linear infinite; }
.brand__mark .spin2 { transform-origin: 24px 24px; animation: spin 11s linear infinite reverse; }
.brand__mark .spin3 { transform-origin: 24px 24px; animation: spin 15s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

.brand__text {
  font-family: var(--font-display);
  font-size: 1.02rem; font-weight: 700;
  letter-spacing: 0.035em;
  color: var(--ink);
  line-height: 1;
}
.brand__text span { color: var(--beam); }
.brand:hover .brand__text { color: #fff; }

/* --- Links --- */
.nav__links { display: flex; align-items: center; gap: 0.15rem; margin-left: auto; }
.nav__link {
  position: relative;
  padding: 0.55rem 0.85rem;
  font-family: var(--font-display);
  font-size: var(--t-sm);
  font-weight: 500;
  color: var(--ink-2);
  border-radius: var(--r-2);
  transition: color var(--d-2) var(--e-out), background var(--d-2) var(--e-out);
  white-space: nowrap;
}
.nav__link:hover { color: var(--ink); background: rgba(255,255,255,0.05); }
.nav__link::after {
  content: ''; position: absolute; left: 0.85rem; right: 0.85rem; bottom: 0.28rem;
  height: 1px; background: var(--beam);
  transform: scaleX(0); transform-origin: left;
  transition: transform var(--d-2) var(--e-out);
}
.nav__link:hover::after { transform: scaleX(1); }
.nav__link.is-current { color: var(--ink); }
.nav__link.is-current::after { transform: scaleX(1); box-shadow: 0 0 8px var(--beam); }

.nav__actions { display: flex; align-items: center; gap: 0.5rem; flex: none; }

/* --- Search trigger --- */
.navsearch {
  display: inline-flex; align-items: center; gap: 0.6rem;
  padding: 0.46rem 0.6rem 0.46rem 0.8rem;
  min-width: 210px;
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--edge);
  border-radius: var(--r-3);
  color: var(--ink-3);
  font-size: var(--t-xs);
  cursor: pointer;
  transition: all var(--d-2) var(--e-out);
}
.navsearch:hover { border-color: rgba(89,230,255,0.4); color: var(--ink-2); background: rgba(89,230,255,0.06); }
.navsearch svg { width: 14px; height: 14px; flex: none; opacity: 0.8; }
.navsearch__hint { margin-left: auto; display: flex; gap: 2px; }

.nav__burger { display: none; width: 38px; height: 38px; border-radius: var(--r-2); border: 1px solid var(--edge); }
.nav__burger span { display: block; width: 16px; height: 1.5px; background: var(--ink); margin: 3px auto; border-radius: 2px; transition: transform var(--d-2) var(--e-out), opacity var(--d-1); }
.nav__burger[aria-expanded="true"] span:nth-child(1) { transform: translateY(4.5px) rotate(45deg); }
.nav__burger[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav__burger[aria-expanded="true"] span:nth-child(3) { transform: translateY(-4.5px) rotate(-45deg); }

/* --- Language --- */
.lang { position: relative; }
.lang__btn {
  display: inline-flex; align-items: center; gap: 0.4rem;
  padding: 0.5rem 0.7rem;
  border: 1px solid var(--edge); border-radius: var(--r-2);
  font-family: var(--font-mono); font-size: var(--t-3xs);
  letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-2);
  transition: all var(--d-2) var(--e-out);
}
.lang__btn:hover { border-color: var(--edge-strong); color: var(--ink); background: rgba(255,255,255,0.05); }
.lang__menu {
  position: absolute; top: calc(100% + 8px); right: 0;
  min-width: 172px; padding: 0.4rem;
  background: rgba(8, 12, 20, 0.96);
  border: 1px solid var(--edge-strong); border-radius: var(--r-3);
  backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px);
  box-shadow: var(--lift-3);
  opacity: 0; visibility: hidden; transform: translateY(-6px);
  transition: all var(--d-2) var(--e-out);
  max-height: 60vh; overflow-y: auto;
}
.lang.is-open .lang__menu { opacity: 1; visibility: visible; transform: none; }
.lang__item {
  display: flex; align-items: center; gap: 0.6rem;
  padding: 0.5rem 0.7rem; border-radius: var(--r-2);
  font-size: var(--t-xs); color: var(--ink-2);
  transition: all var(--d-1);
}
.lang__item:hover { background: rgba(255,255,255,0.07); color: var(--ink); }
.lang__item.is-current { color: var(--beam); background: rgba(89,230,255,0.09); }
.lang__code { font-family: var(--font-mono); font-size: var(--t-3xs); letter-spacing: 0.08em; color: var(--ink-3); margin-left: auto; }

/* --- Mobile drawer --- */
.nav__drawer {
  position: fixed; inset: var(--nav-h) 0 0 0;
  z-index: 199;
  background: rgba(4, 6, 11, 0.97);
  backdrop-filter: blur(22px); -webkit-backdrop-filter: blur(22px);
  padding: var(--s-5) var(--gutter) var(--s-8);
  display: flex; flex-direction: column; gap: var(--s-2);
  opacity: 0; visibility: hidden; transform: translateY(-10px);
  transition: all var(--d-3) var(--e-out);
  overflow-y: auto;
}
.nav__drawer.is-open { opacity: 1; visibility: visible; transform: none; }
.nav__drawer .nav__link {
  font-size: var(--t-lg); padding: 0.9rem 0.5rem;
  border-bottom: 1px solid var(--edge-soft); border-radius: 0;
}
.nav__drawer .nav__link::after { display: none; }

@media (max-width: 1080px) {
  .navsearch { min-width: 44px; padding: 0.5rem; }
  .navsearch__label, .navsearch__hint { display: none; }
}
@media (max-width: 900px) {
  .nav__links { display: none; }
  .nav__burger { display: block; }
}

/* ---------------------------------------------------------------------------
   COMMAND PALETTE
   ------------------------------------------------------------------------- */
.cmdk {
  position: fixed; inset: 0; z-index: 400;
  display: grid; place-items: start center;
  padding: clamp(3rem, 12vh, 9rem) var(--gutter) var(--s-6);
  background: rgba(2, 4, 8, 0.72);
  backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px);
  opacity: 0; visibility: hidden;
  transition: opacity var(--d-2) var(--e-out), visibility var(--d-2);
}
.cmdk.is-open { opacity: 1; visibility: visible; }
.cmdk__box {
  width: 100%; max-width: 680px;
  background: rgba(9, 13, 22, 0.97);
  border: 1px solid var(--edge-strong);
  border-radius: var(--r-4);
  box-shadow: 0 40px 100px -24px rgba(0,0,0,0.95), 0 0 0 1px rgba(89,230,255,0.09);
  overflow: hidden;
  transform: translateY(-14px) scale(0.98);
  transition: transform var(--d-3) var(--e-spring);
  display: flex; flex-direction: column;
  max-height: min(70vh, 620px);
}
.cmdk.is-open .cmdk__box { transform: none; }
.cmdk__head { display: flex; align-items: center; gap: 0.8rem; padding: 0.9rem 1.1rem; border-bottom: 1px solid var(--edge); }
.cmdk__head svg { width: 17px; height: 17px; color: var(--beam); flex: none; }
.cmdk__input {
  flex: 1; background: none; border: none; outline: none;
  font-size: var(--t-md); color: var(--ink);
}
.cmdk__input::placeholder { color: var(--ink-3); }
.cmdk__results { overflow-y: auto; padding: 0.4rem; }
.cmdk__group { padding: 0.6rem 0.75rem 0.3rem; font-family: var(--font-mono); font-size: var(--t-3xs); letter-spacing: 0.16em; text-transform: uppercase; color: var(--ink-3); }
.cmdk__row {
  display: flex; align-items: center; gap: 0.85rem;
  padding: 0.6rem 0.75rem; border-radius: var(--r-2);
  cursor: pointer; transition: background var(--d-1);
}
.cmdk__row:hover, .cmdk__row.is-sel { background: rgba(89,230,255,0.1); }
.cmdk__row.is-sel { box-shadow: inset 2px 0 0 var(--beam); }
.cmdk__sym {
  width: 38px; height: 38px; flex: none;
  display: grid; place-items: center;
  border-radius: var(--r-2);
  font-family: var(--font-display); font-weight: 700; font-size: var(--t-sm);
  color: var(--fam, var(--beam));
  background: color-mix(in srgb, var(--fam, var(--beam)) 14%, transparent);
  border: 1px solid color-mix(in srgb, var(--fam, var(--beam)) 32%, transparent);
}
.cmdk__name { font-weight: 500; font-size: var(--t-sm); }
.cmdk__meta { font-family: var(--font-mono); font-size: var(--t-3xs); color: var(--ink-3); letter-spacing: 0.06em; }
.cmdk__num  { margin-left: auto; font-family: var(--font-mono); font-size: var(--t-2xs); color: var(--ink-3); }
.cmdk__foot {
  display: flex; align-items: center; gap: var(--s-4);
  padding: 0.6rem 1.1rem; border-top: 1px solid var(--edge);
  font-size: var(--t-3xs); color: var(--ink-3);
  font-family: var(--font-mono); letter-spacing: 0.06em;
}
.cmdk__foot span { display: inline-flex; align-items: center; gap: 0.35rem; }
.cmdk__empty { padding: 2.5rem 1rem; text-align: center; color: var(--ink-3); font-size: var(--t-sm); }

/* ---------------------------------------------------------------------------
   FOOTER
   ------------------------------------------------------------------------- */
.foot {
  position: relative;
  /* No top margin: the preceding .section already contributes its own bottom
     padding, and stacking the two produced a dead band above the footer. */
  margin-top: 0;
  border-top: 1px solid var(--edge);
  background: linear-gradient(180deg, rgba(255,255,255,0.016), transparent 40%);
  padding-block: clamp(2.5rem, 5vw, 4.5rem) var(--s-5);
}
.foot__grid {
  display: grid;
  grid-template-columns: minmax(240px, 1.5fr) repeat(3, minmax(140px, 1fr));
  gap: clamp(1.5rem, 4vw, 3.5rem);
}
.foot__title { font-family: var(--font-mono); font-size: var(--t-3xs); letter-spacing: 0.18em; text-transform: uppercase; color: var(--ink-3); margin-bottom: var(--s-4); }
.foot__links { display: flex; flex-direction: column; gap: 0.55rem; }
.foot__links a { font-size: var(--t-sm); color: var(--ink-2); transition: color var(--d-1), transform var(--d-2) var(--e-out); display: inline-block; }
.foot__links a:hover { color: var(--beam); transform: translateX(3px); }
.foot__about { font-size: var(--t-sm); color: var(--ink-2); line-height: 1.68; max-width: 40ch; }
.foot__bottom {
  margin-top: clamp(2rem, 4vw, 3.5rem); padding-top: var(--s-4);
  border-top: 1px solid var(--edge-soft);
  display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: var(--s-3);
  font-size: var(--t-2xs); color: var(--ink-3); font-family: var(--font-mono); letter-spacing: 0.04em;
}
.foot__legend { display: flex; flex-wrap: wrap; gap: 0.4rem 0.85rem; margin-top: var(--s-4); }
.foot__legend span { display: inline-flex; align-items: center; gap: 0.4rem; font-size: var(--t-3xs); color: var(--ink-3); font-family: var(--font-mono); letter-spacing: 0.06em; }
.foot__legend i { width: 7px; height: 7px; border-radius: 2px; display: block; }

@media (max-width: 820px) {
  .foot__grid { grid-template-columns: 1fr 1fr; }
  .foot__grid > :first-child { grid-column: 1 / -1; }
}
@media (max-width: 480px) {
  .foot__grid { grid-template-columns: 1fr; }
}