/* ════════════════════════════════════════════════════════════════════
   BUDDY ALLOCATOR :: amber CRT theme (compact)
   typography  : JetBrains Mono only — CJK falls back via system fonts
   palette     : warm-dark + phosphor amber + lime/coral/cyan accents
═══════════════════════════════════════════════════════════════════ */

:root {
  color-scheme: dark;

  --bg:          #0a0805;
  --bg-warm:     #120c05;
  --panel:       #14100a;
  --panel-tint:  rgba(255, 176, 0, 0.020);
  --panel-edge:  rgba(255, 176, 0, 0.32);
  --panel-edge-soft: rgba(255, 176, 0, 0.14);
  --rule:        rgba(255, 176, 0, 0.18);

  --ink:         #ffe9c1;
  --paper:       #fff5dc;
  --muted:       #8a7549;
  --muted-2:     #6a5a3a;
  --dim:         #4a3e29;

  --amber:       #ffb000;
  --amber-bright:#ffc94a;
  --amber-soft:  rgba(255, 176, 0, 0.14);
  --amber-glow:  rgba(255, 176, 0, 0.32);

  --lime:        #c5f100;
  --lime-soft:   rgba(197, 241, 0, 0.14);
  --lime-glow:   rgba(197, 241, 0, 0.28);

  --coral:       #ff5e52;
  --coral-soft:  rgba(255, 94, 82, 0.14);
  --coral-glow:  rgba(255, 94, 82, 0.28);

  --cyan:        #5eead4;
  --cyan-soft:   rgba(94, 234, 212, 0.14);
  --cyan-glow:   rgba(94, 234, 212, 0.28);

  --crit:        #ff2966;
  --crit-soft:   rgba(255, 41, 102, 0.14);

  --mono: "JetBrains Mono", ui-monospace, "SFMono-Regular", "Cascadia Mono",
          "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", monospace;

  --ease-snap: cubic-bezier(0.2, 0.8, 0.2, 1);
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }

body {
  min-height: 100vh;
  color: var(--ink);
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.5;
  background:
    radial-gradient(ellipse at 50% 0%, rgba(255, 176, 0, 0.05), transparent 55%),
    linear-gradient(180deg, #0c0905 0%, #060402 100%);
  background-attachment: fixed;
  overflow-x: hidden;
}

.crt-overlay {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 100;
  background: repeating-linear-gradient(
    180deg,
    rgba(255, 220, 140, 0.018) 0px,
    rgba(255, 220, 140, 0.018) 1px,
    transparent 1px,
    transparent 3px
  );
}

.shell {
  width: min(1480px, calc(100vw - 28px));
  margin: 0 auto;
  padding: 14px 0 18px;
  position: relative;
  z-index: 1;
}

button, input { font: inherit; color: inherit; }
h1, h2, h3, h4, p, ol, ul { margin: 0; padding: 0; }
ol, ul { list-style: none; }

[hidden] { display: none !important; }

/* ════════════ topbar ════════════ */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
  padding-bottom: 10px;
  border-bottom: 1px dashed var(--panel-edge-soft);
}
.topbar-title {
  display: flex;
  align-items: baseline;
  gap: 8px;
  min-width: 0;
}
.topbar-prompt {
  color: var(--lime);
  font-family: var(--mono);
  font-size: 16px;
  font-weight: 800;
  text-shadow: 0 0 6px var(--lime-glow);
}
.topbar h1 {
  color: var(--amber-bright);
  font-family: var(--mono);
  font-size: clamp(18px, 2.2vw, 24px);
  font-weight: 800;
  letter-spacing: 0.02em;
  text-shadow: 0 0 8px var(--amber-glow);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.cursor.blink {
  display: inline-block;
  color: var(--amber-bright);
  font-weight: 800;
  animation: blink 1s steps(2, jump-none) infinite;
  text-shadow: 0 0 8px var(--amber-glow);
}

.topbar-tools {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.explainer-toggle,
.lang-toggle {
  border: 1px solid var(--panel-edge-soft);
  background: transparent;
  padding: 3px 8px;
  font-family: var(--mono);
  font-size: 10px;
  font-weight: 700;
  color: var(--muted);
  cursor: pointer;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  transition: border-color 140ms, color 140ms, background 140ms;
}
.explainer-toggle:hover,
.lang-toggle:hover {
  border-color: var(--amber);
  color: var(--amber-bright);
  background: var(--amber-soft);
}
.explainer-toggle.active {
  border-color: var(--amber);
  color: var(--amber-bright);
  background: var(--amber-soft);
}
.lang-toggle .lang-opt { padding: 0 1px; transition: color 140ms; }
.lang-toggle .lang-sep { color: var(--dim); margin: 0 1px; }
[data-lang="zh"] .lang-toggle .lang-opt.zh,
[data-lang="en"] .lang-toggle .lang-opt.en {
  color: var(--amber-bright);
  text-shadow: 0 0 6px var(--amber-glow);
}

/* ════════════ stats row ════════════ */
.stats {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 8px;
  margin-bottom: 10px;
}
.stat {
  position: relative;
  padding: 6px 10px 5px;
  background: rgba(255, 176, 0, 0.03);
  border: 1px solid var(--rule);
  display: flex;
  flex-direction: column;
  gap: 1px;
}
.stat-num {
  display: block;
  font-family: var(--mono);
  font-size: 20px;
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: 0.01em;
  color: var(--amber-bright);
  text-shadow: 0 0 8px var(--amber-glow);
}
.stat[data-tone="lime"] .stat-num { color: var(--lime); text-shadow: 0 0 8px var(--lime-glow); }
.stat[data-tone="coral"] .stat-num { color: var(--coral); text-shadow: 0 0 8px var(--coral-glow); }
.stat[data-tone="cyan"] .stat-num { color: var(--cyan); text-shadow: 0 0 8px var(--cyan-glow); }
.stat small {
  display: block;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.04em;
}

/* ════════════ notice ════════════ */
.notice {
  margin-bottom: 10px;
  padding: 6px 12px;
  background: var(--amber-soft);
  border: 1px solid var(--amber);
  border-left-width: 3px;
  color: var(--amber-bright);
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 700;
  text-shadow: 0 0 6px var(--amber-glow);
  animation: noticeFade 2.6s ease-out forwards;
}
.notice::before {
  content: "! ";
  color: var(--amber);
  font-weight: 800;
}

/* ════════════ panel ════════════ */
.panel {
  position: relative;
  padding: 18px 12px 10px;
  background: var(--panel);
  background-image: linear-gradient(180deg, var(--panel-tint), transparent 30%);
  border: 1px solid var(--panel-edge);
  animation: panelIn 0.35s var(--ease-snap) backwards;
}
.panel::before,
.panel::after {
  content: "";
  position: absolute;
  width: 7px;
  height: 7px;
  pointer-events: none;
}
.panel::before {
  top: -1px;
  left: -1px;
  border-top: 2px solid var(--amber);
  border-left: 2px solid var(--amber);
}
.panel::after {
  bottom: -1px;
  right: -1px;
  border-bottom: 2px solid var(--amber);
  border-right: 2px solid var(--amber);
}

.panel-head {
  position: absolute;
  top: -1px;
  left: 10px;
  right: 10px;
  height: 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 0 6px;
  background: var(--bg);
  z-index: 2;
  transform: translateY(-50%);
}
.panel-head h2 {
  color: var(--amber-bright);
  font-family: var(--mono);
  font-size: 10.5px;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  text-shadow: 0 0 6px var(--amber-glow);
  white-space: nowrap;
}

/* ════════════ workspace ════════════ */
.workspace {
  display: grid;
  grid-template-columns: 248px minmax(0, 1fr) 280px;
  gap: 10px;
  align-items: start;
}
.main-stage,
.side-column {
  display: grid;
  gap: 10px;
  min-width: 0;
}

/* ════════════ controls ════════════ */
.control-grid {
  display: grid;
  gap: 8px;
}
label {
  display: grid;
  gap: 4px;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.04em;
}
input {
  height: 32px;
  padding: 0 8px;
  border: 1px solid var(--panel-edge-soft);
  background: rgba(0, 0, 0, 0.36);
  color: var(--ink);
  outline: none;
  font-family: var(--mono);
  font-size: 13px;
  font-weight: 700;
}
input:focus {
  border-color: var(--amber);
  box-shadow: inset 0 0 0 1px var(--amber-soft);
}

.button-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 6px;
  margin-top: 8px;
}
.button-row.triple { grid-template-columns: 1fr 1fr 1fr; }

button {
  min-height: 32px;
  padding: 0 6px;
  border: 1px solid var(--amber);
  background: rgba(255, 176, 0, 0.05);
  color: var(--amber-bright);
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.02em;
  cursor: pointer;
  transition: background 120ms, transform 80ms, box-shadow 120ms;
}
button:hover {
  background: rgba(255, 176, 0, 0.13);
  box-shadow: inset 0 0 0 1px var(--amber);
}
button:active { transform: translateY(1px); }
button:disabled {
  border-color: var(--dim);
  background: rgba(255, 255, 255, 0.02);
  color: var(--muted-2);
  cursor: not-allowed;
  box-shadow: none;
}

button[data-tone="lime"] {
  border-color: var(--lime);
  color: var(--lime);
  background: rgba(197, 241, 0, 0.06);
}
button[data-tone="lime"]:hover { background: rgba(197, 241, 0, 0.13); box-shadow: inset 0 0 0 1px var(--lime); }
button[data-tone="coral"] {
  border-color: var(--coral);
  color: var(--coral);
  background: rgba(255, 94, 82, 0.06);
}
button[data-tone="coral"]:hover { background: rgba(255, 94, 82, 0.13); box-shadow: inset 0 0 0 1px var(--coral); }
button[data-tone="cyan"] {
  border-color: var(--cyan);
  color: var(--cyan);
  background: rgba(94, 234, 212, 0.06);
}
button[data-tone="cyan"]:hover { background: rgba(94, 234, 212, 0.13); box-shadow: inset 0 0 0 1px var(--cyan); }
button[data-tone="ghost"] {
  border-color: var(--panel-edge-soft);
  color: var(--muted);
  background: transparent;
}
button[data-tone="ghost"]:hover { color: var(--ink); border-color: var(--ink); background: rgba(255, 255, 255, 0.03); box-shadow: none; }

.ghost-btn {
  min-height: 20px;
  padding: 0 7px;
  border: 1px dashed var(--panel-edge-soft);
  background: transparent;
  color: var(--muted);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.04em;
}
.ghost-btn:hover {
  background: rgba(255, 176, 0, 0.06);
  border-color: var(--amber);
  border-style: solid;
  color: var(--amber-bright);
  box-shadow: none;
}

.speed-control {
  display: grid;
  gap: 5px;
  margin-top: 12px;
}
.speed-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  font-size: 10px;
  letter-spacing: 0.04em;
}
.speed-row span:last-child {
  color: var(--amber-bright);
  font-family: var(--mono);
  font-weight: 800;
}
.speed-control input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 4px;
  background: var(--dim);
  border: none;
  padding: 0;
  cursor: pointer;
}
.speed-control input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 11px;
  height: 11px;
  background: var(--amber);
  border: 1px solid var(--amber-bright);
  cursor: pointer;
  border-radius: 0;
}
.speed-control input[type="range"]::-moz-range-thumb {
  width: 11px;
  height: 11px;
  background: var(--amber);
  border: 1px solid var(--amber-bright);
  cursor: pointer;
  border-radius: 0;
}

/* script — 2 column compact list */
.script { margin-top: 12px; }
.script h3 {
  color: var(--amber-bright);
  font-family: var(--mono);
  font-size: 10px;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 6px;
  text-shadow: 0 0 6px var(--amber-glow);
}
.script ol {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3px;
  font-family: var(--mono);
  font-size: 10.5px;
  color: var(--muted);
  counter-reset: script;
}
.script li {
  counter-increment: script;
  padding: 2px 4px 2px 22px;
  position: relative;
  border-left: 2px solid transparent;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.script li::before {
  content: counter(script, decimal-leading-zero);
  position: absolute;
  left: 4px;
  top: 2px;
  color: var(--dim);
  font-size: 9px;
  font-weight: 700;
}
.script li.active {
  color: var(--amber-bright);
  background: var(--amber-soft);
  border-left-color: var(--amber);
}
.script li.active::before { color: var(--amber); }
.script li.done {
  color: var(--lime);
  opacity: 0.85;
}
.script li.done::before { color: var(--lime); }
.script li.done::after { content: " ✓"; color: var(--lime); font-size: 9px; }

/* ════════════ board ════════════ */
.board { padding-bottom: 10px; }
.board-msg {
  margin: 0 0 8px;
  color: var(--ink);
  font-family: var(--mono);
  font-size: 12px;
  line-height: 1.5;
  opacity: 0.92;
}
.board-msg::before {
  content: "$ ";
  color: var(--lime);
  font-weight: 800;
}

.legend {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 0 4px;
}
.lg {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 9.5px;
  color: var(--muted);
  font-family: var(--mono);
  letter-spacing: 0.02em;
}
.lg i {
  width: 9px;
  height: 9px;
  display: inline-block;
}
.lg-free { background: var(--lime); }
.lg-used { background: var(--coral); }
.lg-active { background: var(--cyan); }

.memory {
  position: relative;
  display: grid;
  grid-template-columns: repeat(16, minmax(0, 1fr));
  gap: 3px;
  min-height: 158px;
  padding: 8px 0 4px;
}
.page {
  position: relative;
  min-height: 96px;
  border: 1px solid var(--rule);
  background:
    linear-gradient(180deg, rgba(255, 176, 0, 0.03), transparent 70%),
    rgba(0, 0, 0, 0.32);
}
.page::after {
  content: attr(data-hex);
  position: absolute;
  left: 50%;
  bottom: 4px;
  transform: translateX(-50%);
  color: var(--muted);
  font-family: var(--mono);
  font-size: 9px;
  font-weight: 700;
}
.page::before {
  content: attr(data-index);
  position: absolute;
  left: 3px;
  top: 3px;
  color: var(--dim);
  font-family: var(--mono);
  font-size: 9px;
  font-weight: 700;
}

.block {
  position: absolute;
  top: 0;
  height: 26px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid transparent;
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.04em;
  white-space: nowrap;
  transition: left 280ms var(--ease-snap),
              width 280ms var(--ease-snap),
              top 280ms var(--ease-snap);
}
.block.free {
  border-color: var(--lime);
  color: var(--lime);
  background: linear-gradient(180deg, rgba(197, 241, 0, 0.20), rgba(197, 241, 0, 0.06));
  text-shadow: 0 0 5px var(--lime-glow);
}
.block.used {
  border-color: var(--coral);
  color: var(--coral);
  background: linear-gradient(180deg, rgba(255, 94, 82, 0.22), rgba(255, 94, 82, 0.07));
  text-shadow: 0 0 5px var(--coral-glow);
}
.block.active {
  animation: pulse 900ms ease-in-out 2;
  box-shadow: 0 0 0 2px var(--cyan), 0 0 14px var(--cyan-glow);
  border-color: var(--cyan);
  color: var(--cyan);
}
.block.splitting { animation: split 600ms var(--ease-snap); }
.block.merging { animation: merge 600ms var(--ease-snap); }

.addr-scale {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  margin-top: 6px;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 9.5px;
  font-weight: 700;
}
.addr-scale span:not(:first-child):not(:last-child) { text-align: center; }
.addr-scale span:last-child { text-align: right; }


/* ════════════ tree + areas (right under memory) ════════════ */
.lower-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 10px;
}
.tree { display: grid; gap: 3px; }
.tree-row {
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  gap: 6px;
  align-items: center;
}
.tree-label {
  color: var(--amber);
  font-family: var(--mono);
  font-size: 9.5px;
  font-weight: 800;
  letter-spacing: 0.04em;
}
.tree-track {
  display: grid;
  gap: 3px;
}
.tree-node {
  min-height: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--rule);
  padding: 0 3px;
  color: var(--muted-2);
  background: rgba(0, 0, 0, 0.22);
  font-family: var(--mono);
  font-size: 9.5px;
  font-weight: 700;
  overflow: hidden;
}
.tree-node.free {
  border-color: var(--lime);
  color: var(--lime);
  background: var(--lime-soft);
}
.tree-node.used {
  border-color: var(--coral);
  color: var(--coral);
  background: var(--coral-soft);
}
.tree-node.split {
  color: var(--amber);
  background: var(--amber-soft);
  border-color: var(--amber);
  border-style: dashed;
}

.area-list {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 6px;
}
.area {
  min-height: 56px;
  border: 1px solid var(--rule);
  padding: 6px 6px 4px;
  background: rgba(0, 0, 0, 0.24);
}
.area strong {
  display: block;
  margin-bottom: 4px;
  color: var(--amber);
  font-family: var(--mono);
  font-size: 10px;
  font-weight: 800;
  letter-spacing: 0.02em;
}
.area > span {
  display: inline-block;
  margin: 0 2px 2px 0;
  padding: 1px 5px;
  background: var(--lime-soft);
  color: var(--lime);
  border: 1px solid rgba(197, 241, 0, 0.32);
  font-family: var(--mono);
  font-size: 9.5px;
  font-weight: 700;
}
.area > span.empty {
  background: transparent;
  color: var(--dim);
  border-style: dashed;
  border-color: var(--dim);
}

/* ════════════ allocations ════════════ */
.allocation-list {
  display: grid;
  gap: 5px;
  height: 150px;             /* fixed: panel doesn't reflow as pids come and go */
  overflow-y: auto;
  align-content: start;
  padding-right: 4px;
  scrollbar-width: thin;
  scrollbar-color: var(--coral) transparent;
}
.allocation-list::-webkit-scrollbar { width: 5px; }
.allocation-list::-webkit-scrollbar-thumb { background: var(--coral); }
.allocation-list::-webkit-scrollbar-track { background: rgba(255, 94, 82, 0.06); }
.allocation {
  display: grid;
  grid-template-columns: 26px minmax(0, 1fr);
  gap: 8px;
  align-items: center;
  padding: 6px 8px;
  border: 1px solid var(--rule);
  background: rgba(0, 0, 0, 0.24);
  position: relative;
}
.allocation::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--coral);
}
.allocation b {
  display: grid;
  place-items: center;
  width: 24px;
  height: 24px;
  border: 1px solid var(--coral);
  background: var(--coral-soft);
  color: var(--coral);
  font-family: var(--mono);
  font-size: 13px;
  font-weight: 800;
  text-shadow: 0 0 4px var(--coral-glow);
}
.allocation p {
  color: var(--ink);
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 700;
}
.allocation small {
  display: block;
  margin-top: 1px;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 10px;
}
.allocation.empty {
  display: block;
  padding: 10px;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 11px;
  line-height: 1.5;
  border-style: dashed;
}
.allocation.empty::before { display: none; }

/* ════════════ log ════════════ */
.log {
  display: grid;
  gap: 2px;
  height: 320px;             /* fills side column now that allocations panel is gone */
  overflow-y: auto;
  align-content: start;
  padding-right: 4px;
  font-family: var(--mono);
  scrollbar-width: thin;
  scrollbar-color: var(--amber) transparent;
}
.log::-webkit-scrollbar { width: 5px; }
.log::-webkit-scrollbar-thumb { background: var(--amber); }
.log::-webkit-scrollbar-track { background: rgba(255, 176, 0, 0.06); }

.entry {
  display: grid;
  grid-template-columns: 32px minmax(0, 1fr);
  gap: 5px;
  padding: 2px 5px;
  font-size: 10.5px;
  line-height: 1.4;
  color: var(--ink);
  border-left: 2px solid var(--amber);
  background: rgba(255, 176, 0, 0.03);
}
.entry .tag {
  color: var(--amber);
  font-weight: 800;
  font-size: 9.5px;
}
.entry .text { color: var(--ink); opacity: 0.92; }
.entry[data-kind="alloc"] { border-color: var(--lime); background: rgba(197, 241, 0, 0.04); }
.entry[data-kind="alloc"] .tag { color: var(--lime); }
.entry[data-kind="free"] { border-color: var(--coral); background: rgba(255, 94, 82, 0.04); }
.entry[data-kind="free"] .tag { color: var(--coral); }
.entry[data-kind="split"] { border-color: var(--amber); }
.entry[data-kind="split"] .tag { color: var(--amber); }
.entry[data-kind="merge"] { border-color: var(--cyan); background: rgba(94, 234, 212, 0.04); }
.entry[data-kind="merge"] .tag { color: var(--cyan); }
.entry[data-kind="info"] { border-color: var(--muted-2); }
.entry[data-kind="info"] .tag { color: var(--muted); }
.entry[data-kind="error"] { border-color: var(--crit); background: var(--crit-soft); }
.entry[data-kind="error"] .tag { color: var(--crit); text-shadow: 0 0 4px rgba(255, 41, 102, 0.3); }

/* ════════════ explainer (collapsible) ════════════ */
.explainer {
  margin-top: 10px;
}
.explain-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(180px, 0.85fr) minmax(0, 1fr);
  gap: 8px;
}
.trace-cell {
  position: relative;
  padding: 8px 10px;
  border: 1px solid var(--rule);
  background: rgba(0, 0, 0, 0.28);
}
.trace-cell::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--amber);
}
.trace-cell[data-tone="cyan"]::before { background: var(--cyan); }
.trace-cell[data-tone="amber"]::before { background: var(--amber); }
.trace-cell[data-tone="lime"]::before { background: var(--lime); }
.trace-cell small {
  display: block;
  margin-bottom: 5px;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 9.5px;
  font-weight: 700;
  letter-spacing: 0.06em;
}
.trace-cell h3 {
  color: var(--amber-bright);
  font-family: var(--mono);
  font-size: 14px;
  font-weight: 800;
  line-height: 1.2;
  text-shadow: 0 0 5px var(--amber-glow);
  margin-bottom: 4px;
}
.trace-cell p {
  color: var(--ink);
  font-family: var(--mono);
  font-size: 11.5px;
  line-height: 1.55;
  opacity: 0.92;
}
code {
  display: block;
  color: var(--amber-bright);
  font-family: var(--mono);
  font-size: 11.5px;
  line-height: 1.55;
  white-space: pre-wrap;
}

/* ════════════ animations ════════════ */
@keyframes blink {
  0%, 50% { opacity: 1; }
  50.01%, 100% { opacity: 0; }
}
@keyframes pulse {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-2px); }
}
@keyframes split {
  0% { transform: scaleX(1.06); opacity: 0.55; }
  100% { transform: scaleX(1); opacity: 1; }
}
@keyframes merge {
  0% { transform: scaleY(0.78); opacity: 0.55; }
  100% { transform: scaleY(1); opacity: 1; }
}
@keyframes panelIn {
  from { opacity: 0; transform: translateY(4px); }
  to { opacity: 1; transform: translateY(0); }
}
@keyframes noticeFade {
  0%   { opacity: 0; transform: translateY(-4px); }
  10%  { opacity: 1; transform: translateY(0); }
  85%  { opacity: 1; }
  100% { opacity: 0; }
}

/* ════════════ responsive ════════════ */
@media (max-width: 1180px) {
  .workspace { grid-template-columns: 1fr; }
  .lower-grid { grid-template-columns: 1fr 1fr; }
  .side-column { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 760px) {
  .shell { padding: 10px 0; width: min(100vw - 14px, 1480px); }
  .topbar h1 { font-size: 16px; }
  .stats { grid-template-columns: 1fr 1fr; }
  .side-column { grid-template-columns: 1fr; }
  .lower-grid { grid-template-columns: 1fr; }
  .area-list { grid-template-columns: repeat(5, minmax(48px, 1fr)); overflow-x: auto; }
  .button-row.triple { grid-template-columns: 1fr 1fr; }
  .memory { overflow-x: auto; grid-template-columns: repeat(16, 32px); padding-bottom: 10px; }
  .page { min-height: 80px; }
  .stat-num { font-size: 18px; }
  .explain-grid { grid-template-columns: 1fr; }
  .trace-cell h3 { font-size: 13px; }
}

@media (max-width: 480px) {
  .panel-head h2 { font-size: 9.5px; }
  .tree-row { grid-template-columns: 48px minmax(0, 1fr); }
  .script ol { grid-template-columns: 1fr; }
}