/* ============================================================
   strutture.css — Visualizzatore di strutture dati
   Pila (LIFO) · Coda (FIFO) · Albero Binario di Ricerca.
   Usa base.css + lab.css.
   ============================================================ */

.sd-sec { position: relative; z-index: 2; }

/* ---------- Pulsanti ---------- */
.run-btn {
  font-family: var(--font-mono);
  font-size: 0.86rem;
  padding: 0.5rem 1rem;
  border: 1px solid var(--accent);
  border-radius: 100px;
  background: var(--accent);
  color: var(--accent-ink);
  cursor: pointer;
  white-space: nowrap;
  transition: transform 0.15s var(--ease), opacity 0.2s var(--ease);
}
.run-btn:hover { transform: translateY(-1px); }
.run-btn:active { transform: translateY(1px); }
.run-btn:disabled, .ghost-btn:disabled { opacity: 0.4; cursor: not-allowed; transform: none; }

/* ---------- Controlli ---------- */
.sd-controls { gap: 1.25rem 2rem; }
.sd-modegroup { align-items: flex-start; }
.sd-modeseg { flex-wrap: wrap; border-radius: 14px; max-width: 100%; }
.sd-val-field { width: 130px; }
.sd-aux-field { width: 110px; }
.sd-val-field input, .sd-aux-field input { text-align: left; }
.sd-actions { display: flex; flex-wrap: wrap; gap: 0.5rem; align-items: center; }
@media (max-width: 620px) { .sd-actions { width: 100%; } }
.sd-ops .sd-ops-label {
  width: 100%;
  margin-bottom: 0.2rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent);
}

/* ---------- Pannello spiegazione ---------- */
.explain-panel { padding: clamp(1.4rem, 3vw, 1.9rem); }
.explain-head { display: flex; align-items: baseline; justify-content: space-between; gap: 1rem; flex-wrap: wrap; margin-bottom: 0.6rem; }
.explain-head h2 { font-family: var(--font-display); font-weight: 500; font-size: clamp(1.4rem, 3vw, 1.9rem); letter-spacing: -0.02em; }
.explain-big {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.1em;
  color: var(--accent-ink);
  background: var(--accent);
  padding: 0.25rem 0.6rem;
  border-radius: 100px;
}
.explain-idea { color: var(--ink); font-size: 1.02rem; max-width: 70ch; margin-bottom: 1.3rem; }
.explain-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.25rem; }
@media (max-width: 760px) { .explain-grid { grid-template-columns: 1fr; gap: 1rem; } }
.explain-item { border-top: 1px solid var(--line); padding-top: 0.8rem; }
.explain-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.4rem;
}
.explain-item p { color: var(--ink-soft); font-size: 0.92rem; }

/* ---------- Layout viz + codice ---------- */
.sd-layout { display: grid; grid-template-columns: 1.35fr 1fr; gap: 1.25rem; align-items: start; }
@media (max-width: 880px) { .sd-layout { grid-template-columns: 1fr; } }

.sd-viz { display: flex; flex-direction: column; }
.sd-viz-stage {
  position: relative;
  min-height: 340px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background:
    radial-gradient(circle at 1px 1px, var(--line-soft) 1px, transparent 0) 0 0 / 22px 22px,
    var(--bg-sunk);
  overflow: auto;
  padding: 1rem;
}

.sd-status {
  margin-top: 0.9rem;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--ink-soft);
  min-height: 1.2rem;
}
.sd-status strong { color: var(--accent); font-weight: 600; }

.sd-log-wrap { margin-top: 0.9rem; }
.sd-log {
  margin-top: 0.4rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  max-height: 84px;
  overflow-y: auto;
}
.sd-log span {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 0.2rem 0.5rem;
  border: 1px solid var(--line);
  border-radius: 6px;
  color: var(--ink-soft);
  background: var(--bg);
  white-space: nowrap;
}
.sd-log span.ins { border-color: color-mix(in srgb, var(--accent) 45%, var(--line)); color: var(--accent); }
.sd-log span.rem { border-color: color-mix(in srgb, #e0533d 45%, var(--line)); color: #e0533d; }
.sd-log-empty { color: var(--ink-faint); }

/* ============================================================
   PILA (stack) — colonna verticale, ultimo in alto
   ============================================================ */
.sd-stack { display: flex; flex-direction: column-reverse; align-items: center; gap: 0.5rem; min-height: 300px; justify-content: flex-start; padding-top: 2.2rem; }
.sd-stack-base {
  width: clamp(120px, 60%, 200px);
  border-bottom: 3px solid var(--ink);
  text-align: center;
  font-family: var(--font-mono);
  font-size: 0.66rem;
  color: var(--ink-faint);
  padding-bottom: 0.25rem;
}
.sd-cell {
  width: clamp(120px, 60%, 200px);
  padding: 0.7rem 1rem;
  border: 1.5px solid var(--ink);
  border-radius: 8px;
  background: var(--bg-elev);
  font-family: var(--font-mono);
  font-size: 1.05rem;
  font-weight: 500;
  text-align: center;
  position: relative;
}
.sd-cell.top, .sd-cell.front, .sd-cell.rear { border-color: var(--accent); }
/* stati di evidenziazione condivisi (array/tupla/lista/dict/set) */
.sd-cell.visiting { border-color: var(--accent); background: color-mix(in srgb, var(--accent) 16%, var(--bg-elev)); }
.sd-cell.found { border-color: var(--accent); background: var(--accent); color: var(--accent-ink); }
.sd-cell.fresh { animation: sd-pop 0.4s var(--ease); }
.sd-cell.ro { background: var(--bg-sunk); border-style: dashed; }

/* ============================================================
   ARRAY · TUPLA — celle indicizzate
   ============================================================ */
.sd-array, .sd-tuple { display: flex; align-items: center; flex-wrap: wrap; gap: 6px; min-height: 300px; padding: 1rem 0.5rem; align-content: center; }
.sd-acell { display: flex; flex-direction: column; align-items: center; gap: 4px; }
.sd-idx { font-family: var(--font-mono); font-size: 0.66rem; color: var(--ink-faint); }
.sd-array .sd-cell, .sd-tuple .sd-cell { width: auto; min-width: 50px; padding: 0.7rem 0.6rem; }
.sd-tuple .sd-paren { font-family: var(--font-display); font-size: 2.4rem; color: var(--ink-faint); line-height: 1; align-self: flex-end; padding-bottom: 0.3rem; }
.sd-lock { align-self: flex-start; font-size: 0.95rem; margin-left: 0.3rem; }

/* ============================================================
   LISTA CONCATENATA — nodi con frecce
   ============================================================ */
.sd-list { display: flex; align-items: center; flex-wrap: wrap; gap: 0; min-height: 300px; padding: 1rem 0.5rem; align-content: center; }
.sd-llabel { font-family: var(--font-mono); font-size: 0.7rem; color: var(--accent); }
.sd-lnode { display: flex; border: 1.5px solid var(--ink); border-radius: 8px; overflow: hidden; background: var(--bg-elev); font-family: var(--font-mono); }
.sd-lval { padding: 0.7rem 0.8rem; font-size: 1.02rem; font-weight: 500; }
.sd-lnext { padding: 0 0.5rem; border-left: 1.5px solid var(--ink); color: var(--ink-faint); display: grid; place-items: center; background: var(--bg-sunk); font-size: 0.7rem; }
.sd-arrow { color: var(--ink-soft); padding: 0 6px; font-size: 1.1rem; }
.sd-null { font-family: var(--font-mono); font-size: 0.78rem; color: var(--ink-faint); border: 1px dashed var(--line); border-radius: 6px; padding: 0.5rem 0.55rem; }
.sd-lnode.visiting { border-color: var(--accent); } .sd-lnode.visiting .sd-lnext { border-color: var(--accent); }
.sd-lnode.found { border-color: var(--accent); background: var(--accent); color: var(--accent-ink); }
.sd-lnode.found .sd-lnext { border-color: var(--accent-ink); color: var(--accent-ink); background: transparent; }
.sd-lnode.fresh { animation: sd-pop 0.4s var(--ease); }

/* ============================================================
   DIZIONARIO — coppie chiave : valore
   ============================================================ */
.sd-dict { display: flex; flex-direction: column; gap: 0.45rem; min-height: 300px; padding: 1rem; align-content: start; justify-content: center; }
.sd-pair { display: flex; align-items: center; gap: 0.55rem; border: 1.5px solid var(--ink); border-radius: 8px; padding: 0.5rem 0.85rem; background: var(--bg-elev); font-family: var(--font-mono); width: fit-content; min-width: 200px; }
.sd-key { color: var(--accent); font-weight: 600; }
.sd-colon { color: var(--ink-faint); }
.sd-dval { margin-left: auto; font-weight: 500; }
.sd-pair.visiting, .sd-pair.found { border-color: var(--accent); background: color-mix(in srgb, var(--accent) 14%, var(--bg-elev)); }
.sd-pair.fresh { animation: sd-pop 0.4s var(--ease); }

/* ============================================================
   SET — chip in un insieme
   ============================================================ */
.sd-set { display: flex; align-items: center; flex-wrap: wrap; gap: 0.5rem; min-height: 300px; padding: 1rem; align-content: center; font-family: var(--font-mono); }
.sd-brace { font-family: var(--font-display); font-size: 2.2rem; color: var(--ink-faint); line-height: 1; }
.sd-chip { border: 1.5px solid var(--ink); border-radius: 100px; padding: 0.5rem 0.9rem; background: var(--bg-elev); font-size: 1.02rem; font-weight: 500; }
.sd-chip.found { border-color: var(--accent); background: var(--accent); color: var(--accent-ink); }
.sd-chip.fresh { animation: sd-pop 0.4s var(--ease); }
.sd-chip.dup { border-color: #e0533d; color: #e0533d; animation: sd-shake 0.4s var(--ease); }
@keyframes sd-shake { 0%,100% { transform: translateX(0); } 25% { transform: translateX(-4px); } 75% { transform: translateX(4px); } }
.sd-ptr {
  position: absolute;
  font-family: var(--font-mono);
  font-size: 0.64rem;
  letter-spacing: 0.04em;
  color: var(--accent);
  white-space: nowrap;
}
.sd-stack .sd-ptr { right: calc(100% + 0.6rem); top: 50%; transform: translateY(-50%); }

/* animazioni inserimento/rimozione */
@keyframes sd-in-top { from { opacity: 0; transform: translateY(-22px); } to { opacity: 1; transform: none; } }
@keyframes sd-out-top { to { opacity: 0; transform: translateY(-22px); } }
@keyframes sd-in-right { from { opacity: 0; transform: translateX(22px); } to { opacity: 1; transform: none; } }
@keyframes sd-out-left { to { opacity: 0; transform: translateX(-22px); } }
@keyframes sd-pop { 0% { transform: scale(0.6); opacity: 0; } 60% { transform: scale(1.08); } 100% { transform: scale(1); opacity: 1; } }
.sd-cell.enter-top { animation: sd-in-top 0.32s var(--ease); }
.sd-cell.leave-top { animation: sd-out-top 0.3s var(--ease) forwards; }
.sd-cell.enter-right { animation: sd-in-right 0.32s var(--ease); }
.sd-cell.leave-left { animation: sd-out-left 0.3s var(--ease) forwards; }

/* ============================================================
   CODA (queue) — riga orizzontale, front a sinistra
   ============================================================ */
.sd-queue { display: flex; align-items: center; gap: 0.5rem; min-height: 300px; padding: 1rem 0.5rem; flex-wrap: nowrap; }
.sd-queue .sd-cell { min-width: 64px; padding: 0.9rem 0.6rem; }
.sd-queue .sd-ptr { left: 50%; transform: translateX(-50%); top: calc(100% + 0.4rem); }
.sd-queue .sd-cell.front .sd-ptr.front { color: var(--accent); }
.sd-queue-empty, .sd-stack-empty, .sd-bst-empty {
  margin: auto;
  color: var(--ink-faint);
  font-size: 0.92rem;
  text-align: center;
  align-self: center;
}

/* ============================================================
   ALBERO BINARIO DI RICERCA (BST)
   ============================================================ */
.sd-bst { min-height: 320px; }
.sd-bst svg { display: block; }
.sd-edge { stroke: var(--ink-soft); stroke-width: 2; }
.sd-node-circle {
  fill: var(--bg-elev);
  stroke: var(--ink);
  stroke-width: 1.8;
  transition: fill 0.2s var(--ease), stroke 0.2s var(--ease);
}
.sd-node-text { fill: var(--ink); font-family: var(--font-mono); font-size: 0.92rem; font-weight: 500; text-anchor: middle; dominant-baseline: central; }
.sd-node.visiting .sd-node-circle { fill: color-mix(in srgb, var(--accent) 22%, var(--bg-elev)); stroke: var(--accent); }
.sd-node.found .sd-node-circle { fill: var(--accent); stroke: var(--accent); }
.sd-node.found .sd-node-text { fill: var(--accent-ink); }
.sd-node.justadded .sd-node-circle { animation: sd-pop 0.4s var(--ease); }
.sd-node.target .sd-node-circle { stroke: #e0533d; fill: color-mix(in srgb, #e0533d 18%, var(--bg-elev)); }

/* ---------- Codice ---------- */
.sd-code { min-width: 0; }
.lang-bar { display: flex; align-items: center; justify-content: space-between; gap: 1rem; margin-bottom: 1rem; flex-wrap: wrap; }
.code-view {
  margin: 0;
  padding: 1rem;
  background: var(--bg-sunk);
  border: 1px solid var(--line);
  border-radius: 10px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.65;
  color: var(--ink);
  overflow-x: auto;
  white-space: pre;
  tab-size: 2;
}
.code-view .cmt { color: var(--ink-faint); font-style: italic; }
.code-view .kw { color: var(--accent); }

@media (prefers-reduced-motion: reduce) {
  .sd-cell, .sd-node-circle, .sd-lnode, .sd-pair, .sd-chip { animation: none !important; }
}