:root {
  /* svetlá denná obloha v FF modrej */
  --sky-1: #eef3fa;   /* hore */
  --sky-2: #cfdcef;   /* dole */
  --bark: #1a3a6b;
  --bark-light: #3c5f96;
  --bark-dark: #0e2140;
  --gold: #cf9f3f;
  --gold-bright: #e8bf63;
  --gold-dim: #9a7530;
  --card-bg: #fbf3df;
  --ink: #1a3a6b;         /* FF modrá pre nadpisy/texty */
  --ink-soft: #47597a;    /* tlmené modré písmo */
  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0; padding: 0; width: 100%; height: 100%;
  background: var(--sky-1); overflow: hidden;
}
body {
  position: relative; min-height: 100dvh;
  font-family: var(--sans); color: var(--ink);
  -webkit-font-smoothing: antialiased;
}

.stage {
  position: absolute; inset: 0; overflow: hidden;
  background:
    radial-gradient(ellipse 80% 60% at 50% 8%, #ffffff 0%, transparent 55%),
    radial-gradient(ellipse 90% 75% at 50% 100%, var(--sky-2) 0%, var(--sky-1) 60%),
    linear-gradient(180deg, var(--sky-1) 0%, #e2eaf5 55%, var(--sky-2) 100%);
}
/* jemný zlatý peľ vo vzduchu */
.stage::before {
  content: ""; position: absolute; inset: 0; pointer-events: none;
  background-image:
    radial-gradient(2px 2px at 18% 20%, rgba(207,159,63,0.18) 50%, transparent 51%),
    radial-gradient(2px 2px at 72% 14%, rgba(207,159,63,0.14) 50%, transparent 51%),
    radial-gradient(1.5px 1.5px at 84% 30%, rgba(207,159,63,0.16) 50%, transparent 51%),
    radial-gradient(1.5px 1.5px at 40% 36%, rgba(207,159,63,0.12) 50%, transparent 51%),
    radial-gradient(2px 2px at 12% 46%, rgba(207,159,63,0.12) 50%, transparent 51%);
  opacity: 0.9;
}

/* ---- topbar ---- */
.masthead { position: fixed; top: 26px; left: 30px; z-index: 5; max-width: 400px; }
.eyebrow {
  font-size: 11px; font-weight: 700; letter-spacing: 0.16em;
  text-transform: uppercase; color: var(--gold-dim); margin: 0 0 8px;
}
h1 {
  font-family: var(--serif); font-weight: 400;
  font-size: clamp(23px, 3vw, 33px); line-height: 1.12;
  color: var(--ink); margin: 0 0 8px; text-wrap: balance;
}
.sub { font-size: 13.5px; line-height: 1.5; color: var(--ink-soft); margin: 0; max-width: 42ch; }

.topright { position: fixed; top: 26px; right: 30px; z-index: 5; display: flex; gap: 10px; }
.btn, .langLink {
  background: rgba(255,255,255,0.6); border: 1px solid var(--gold);
  color: var(--gold-dim); font-family: var(--sans); font-size: 11.5px; font-weight: 600;
  letter-spacing: 0.06em; text-transform: uppercase; text-decoration: none;
  padding: 9px 16px; border-radius: 3px; cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
  display: inline-flex; align-items: center;
}
.btn:hover, .langLink:hover { background: var(--gold); color: #fff; border-color: var(--gold); }
.btn:focus-visible, .langLink:focus-visible { outline: 2px solid var(--ink); outline-offset: 2px; }

/* nápoveda „späť" — len keď sme priblížení do hĺbky */
.backhint {
  position: fixed; top: 24px; left: 50%; transform: translateX(-50%);
  z-index: 6; background: rgba(255,255,255,0.9); border: 1px solid rgba(207,159,63,0.5);
  color: var(--ink-soft); font-size: 12px; font-weight: 500; padding: 8px 15px; border-radius: 20px;
  box-shadow: 0 6px 18px rgba(26,58,107,0.16); opacity: 0; pointer-events: none;
  transition: opacity 0.3s ease; white-space: nowrap;
}
body.zoomed .backhint { opacity: 1; }
body.zoomed .legend { opacity: 0; pointer-events: none; }

/* ---- legend ---- */
.legend {
  position: fixed; left: 30px; bottom: 26px; z-index: 5; width: 330px; transition: opacity 0.3s ease;
  background: rgba(255,255,255,0.82); border: 1px solid rgba(26,58,107,0.18);
  border-radius: 4px; padding: 15px 17px; backdrop-filter: blur(4px);
  box-shadow: 0 8px 24px rgba(26,58,107,0.12);
}
.legend .eyebrow { margin-bottom: 10px; }
.legend ul { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 9px; }
.legend li { display: flex; gap: 10px; font-size: 12.5px; line-height: 1.45; color: var(--ink-soft); }
.legend .mk { flex: none; width: 15px; height: 15px; margin-top: 1px; }

/* ---- svg strom ---- */
.canvas-wrap { position: absolute; inset: 0; }
svg#tree { position: absolute; inset: 0; width: 100%; height: 100%; }

.branch-label { font-family: var(--serif); font-size: 16px; font-weight: 600; fill: var(--ink); cursor: pointer; }
.branch-hint { font-family: var(--sans); font-size: 9px; fill: var(--gold-dim); letter-spacing: 0.04em; }

.bud-node { cursor: pointer; }
.bud-node .bud-shape { transition: transform 0.15s ease; transform-box: fill-box; transform-origin: center; }
.bud-node:hover .bud-shape { transform: scale(1.25); }
.bud-node:focus-visible .hit { outline: 2px solid var(--ink); outline-offset: 2px; }

/* konár „rastie": twig sa vykreslí od kmeňa von (stroke-dash), kvet sa rozvinie
   (scale 0→1) so staggerom podľa poradia — celý strom akoby rástol pri rozklikaní */
.twig-group.hidden { pointer-events: none; }
.twig-line {
  fill: none; stroke: var(--bark-light); stroke-width: 1.8; stroke-linecap: round; opacity: 0.85;
  stroke-dashoffset: var(--len, 120);
  transition: stroke-dashoffset 0.5s ease;
}
.twig-group.shown .twig-line { stroke-dashoffset: 0; }

/* hlavný sub-konár (limb) — ZUŽUJÚCA sa vetva (hrubá pri báze, tenká na konci);
   rastie od báze (scale 0→1, transform-origin = bod uzla) */
.limb {
  transform: scale(0);
  transition: transform 0.55s cubic-bezier(0.2, 0.8, 0.3, 1);
}
.twig-group.shown .limb { transform: scale(1); }
.twig-group.hidden .limb { transform: scale(0); }

.blossom { cursor: pointer; }
.blossom .petals {
  transform: scale(0); transform-box: fill-box; transform-origin: center;
  transition: transform 0.42s cubic-bezier(0.2, 1.35, 0.4, 1);
}
.twig-group.shown .blossom .petals { transform: scale(1); }
.twig-group.shown .blossom:hover .petals { transform: scale(1.22); }
.twig-group.shown .blossom.active .petals { transform: scale(1.32); }
.blossom:focus-visible .hit { outline: 2px solid var(--ink); outline-offset: 3px; }

.blossom-label {
  font-family: var(--sans); font-size: 11px; font-weight: 600; fill: #22406e;
  opacity: 0; transition: opacity 0.4s ease;
}
/* popis je klikateľný ako kvet; v zbalenej skupine kliky nechytá, lebo
   .twig-group.hidden má pointer-events: none */
.blossom-label, .twig-group .lbl-bg,
.branch-label, .branch-hint, .lbl-bg-static { cursor: pointer; }
.twig-group.shown .lbl-bg:hover,
.lbl-bg-static:hover { stroke: var(--gold); stroke-width: 1.6; }
.twig-group.shown .blossom-label { opacity: 1; }
.twig-group .lbl-bg {
  opacity: 0; transition: opacity 0.4s ease;
  stroke: rgba(207,159,63,0.55); stroke-width: 1;
}
.twig-group.shown .lbl-bg { opacity: 0.95; }

/* lístky na konároch — dekorácia ako na nástenných rodostromoch */
.leaf { opacity: 0; transition: opacity 0.45s ease; }
.twig-group.shown .leaf { opacity: 0.85; }
.twig-group.hidden .leaf { opacity: 0; display: none; } /* robustné aj bez transitions */

/* SKRYTÁ skupina musí prebiť „shown" PREDKA (vnorené úrovne sa nesmú zobraziť
   skôr, než na ne priamo klikneš). Musí byť AŽ ZA .shown pravidlami. */
.twig-group.hidden .twig-line { stroke-dashoffset: var(--len, 120); }
.twig-group.hidden .blossom .petals { transform: scale(0); }
.twig-group.hidden .blossom-label,
.twig-group.hidden .lbl-bg { opacity: 0; }

/* 3. úroveň (podstránky podstránok) — menšie kvety a popisy */
.blossom-label.lvl3 { font-size: 9.5px; font-weight: 600; fill: #35507e; }
.blossom.has-kids .petals { cursor: pointer; }

/* slnko = pečať fakulty na oblohe */
.sun-rays { transform-box: fill-box; transform-origin: center; }
.sun-halo { transform-box: fill-box; transform-origin: center; }
@media (prefers-reduced-motion: no-preference) {
  .sun-rays { animation: sunspin 140s linear infinite; }
  .sun-halo { animation: sunpulse 7s ease-in-out infinite; }
}
@keyframes sunspin { to { transform: rotate(360deg); } }
@keyframes sunpulse { 0%, 100% { transform: scale(1); } 50% { transform: scale(1.05); } }

/* ---- bočný panel ---- */
.panel {
  position: fixed; top: 50%; right: 30px; z-index: 8; width: 300px;
  transform: translate(340px, -50%); background: var(--card-bg); color: var(--ink);
  border-radius: 4px; box-shadow: 0 18px 40px rgba(26,58,107,0.28), 0 0 0 1px rgba(207,159,63,0.5);
  padding: 20px 22px 22px; opacity: 0; pointer-events: none;
  transition: transform 0.28s cubic-bezier(.2,.7,.2,1), opacity 0.28s ease;
}
.panel.open { transform: translate(0, -50%); opacity: 1; pointer-events: auto; }
.p-cat { font-size: 10.5px; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: var(--gold-dim); margin: 0 0 8px; }
.p-title { font-family: var(--serif); font-size: 20px; line-height: 1.2; margin: 0 0 12px; text-wrap: balance; }
.p-body { font-size: 13px; line-height: 1.55; color: #33507a; margin: 0 0 18px; }
.p-link {
  display: inline-flex; align-items: center; gap: 7px; font-size: 12px; font-weight: 600;
  letter-spacing: 0.02em; text-decoration: none; color: #fff; background: var(--bark);
  padding: 10px 16px; border-radius: 3px; transition: background 0.15s ease;
}
.p-link:hover { background: #24457a; }
.p-note { margin: 14px 0 0; font-size: 10px; color: #7a8bab; line-height: 1.4; }
.p-close {
  position: absolute; top: 12px; right: 12px; width: 26px; height: 26px;
  border: none; background: transparent; color: #9aa8c2; font-size: 18px; cursor: pointer;
  line-height: 1; border-radius: 3px;
}
.p-close:hover { color: var(--bark); }
.p-close:focus-visible { outline: 2px solid var(--gold-dim); outline-offset: 1px; }

/* ---- padajúce lupienky ---- */
.petal-fall {
  position: fixed; top: -20px; width: 8px; height: 8px;
  background: radial-gradient(circle at 35% 30%, var(--gold-bright), var(--gold) 75%);
  border-radius: 60% 0 60% 0; opacity: 0.5; animation: fall linear infinite; pointer-events: none;
}
@keyframes fall {
  0% { transform: translate(0,0) rotate(0deg); }
  100% { transform: translate(var(--drift,40px), 108vh) rotate(300deg); }
}

@media (prefers-reduced-motion: reduce) {
  .petal-fall { animation: none; display: none; }
  .panel, .twig-group, .twig-line, .limb, .blossom .petals, .blossom-label, .lbl-bg,
  .bud-node .bud-shape, .btn, .langLink { transition: none; }
}
@media (max-width: 820px) {
  .legend { width: 250px; }
  .masthead { max-width: 250px; }
  .panel { width: 260px; }
}
@media (max-width: 560px) {
  .masthead { max-width: 200px; }
  h1 { font-size: 20px; }
  .sub { display: none; }
  .legend { display: none; }
}