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

:root {
  --bg: #0a0a14;
  --surface: #12121f;
  --surface2: #1a1a2e;
  --border: #2a2a44;
  --text: #d0d0e0;
  --dim: #666680;
  --accent: #4fc3f7;
  --accent2: #ab47bc;
  --green: #66bb6a;
  --gold: #ffd54f;
  --warn: #ff7043;
  --radius: 10px;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  line-height: 1.6;
  min-height: 100vh;
}

#app {
  max-width: 900px;
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem;
}

header {
  text-align: center;
  margin-bottom: 2rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border);
}

header h1 {
  font-size: 1.8rem;
  color: var(--accent);
  margin-bottom: 0.4rem;
  letter-spacing: -0.02em;
}

.subtitle {
  color: var(--dim);
  font-size: 0.95rem;
}

/* Tabs */
#tabs {
  display: flex;
  gap: 4px;
  margin-bottom: 2rem;
  overflow-x: auto;
  padding-bottom: 4px;
}

.tab {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--dim);
  padding: 0.5rem 1rem;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 0.82rem;
  white-space: nowrap;
  transition: all 0.2s;
}

.tab:hover { color: var(--text); border-color: var(--accent); }
.tab.active {
  background: var(--accent);
  color: var(--bg);
  border-color: var(--accent);
  font-weight: 600;
}

/* Panels */
.panel { display: none; }
.panel.active { display: block; }

.panel h2 {
  font-size: 1.35rem;
  color: var(--accent);
  margin-bottom: 1rem;
}

/* Explainer blocks */
.explainer {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.2rem 1.4rem;
  margin-bottom: 1.2rem;
  font-size: 0.92rem;
}

.explainer p { margin-bottom: 0.6rem; }
.explainer p:last-child { margin-bottom: 0; }
.explainer ul { margin: 0.5rem 0 0.5rem 1.5rem; }
.explainer li { margin-bottom: 0.3rem; }
.explainer code {
  background: var(--surface2);
  padding: 0.15em 0.4em;
  border-radius: 4px;
  font-size: 0.88em;
  color: var(--gold);
}
.explainer strong { color: var(--accent); }
.explainer em { color: var(--gold); font-style: normal; }

/* Demo boxes */
.demo-box {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.4rem;
  margin-bottom: 1.2rem;
}

.demo-box h3 {
  font-size: 1rem;
  color: var(--gold);
  margin-bottom: 0.8rem;
}

.demo-box h4 {
  font-size: 0.85rem;
  color: var(--dim);
  margin-bottom: 0.5rem;
  text-align: center;
}

.demo-box p { font-size: 0.88rem; margin-bottom: 0.6rem; }

.slider-row {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1rem;
}

.slider-row label {
  font-size: 0.85rem;
  color: var(--dim);
  white-space: nowrap;
}

.slider-row label strong { color: var(--accent); }

input[type="range"] {
  flex: 1;
  accent-color: var(--accent);
  height: 6px;
}

.insight {
  font-size: 0.82rem !important;
  color: var(--green) !important;
  font-style: italic;
  margin-top: 0.8rem !important;
  padding: 0.6rem 0.8rem;
  background: rgba(102, 187, 106, 0.08);
  border-radius: 6px;
  border-left: 3px solid var(--green);
}

/* Softmax bars */
#softmaxBars {
  display: flex;
  align-items: flex-end;
  gap: 12px;
  height: 180px;
  padding: 0 1rem;
}

.bar-col {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.bar-wrapper {
  width: 100%;
  height: 140px;
  display: flex;
  align-items: flex-end;
  justify-content: center;
}

.bar {
  width: 80%;
  background: var(--accent);
  border-radius: 4px 4px 0 0;
  transition: height 0.3s ease, background 0.3s ease;
  min-height: 2px;
}

.bar.winner { background: var(--gold); }

.bar-label {
  font-size: 0.7rem;
  color: var(--dim);
}

.bar-value {
  font-size: 0.72rem;
  color: var(--text);
  font-family: monospace;
}

/* Memory slots (tab 2) */
#memorySlots {
  display: flex;
  gap: 8px;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}

.mem-slot {
  background: var(--surface);
  border: 2px solid var(--border);
  border-radius: 8px;
  padding: 0.6rem 0.8rem;
  cursor: pointer;
  text-align: center;
  min-width: 80px;
  transition: all 0.2s;
}

.mem-slot:hover { border-color: var(--accent); }
.mem-slot.active { border-color: var(--gold); background: rgba(255, 213, 79, 0.1); }

.mem-slot .idx { font-size: 0.7rem; color: var(--dim); }
.mem-slot .val { font-size: 1.1rem; color: var(--text); font-family: monospace; font-weight: 600; }

#dotProducts {
  margin: 1rem 0;
  font-family: monospace;
  font-size: 0.82rem;
  line-height: 1.8;
}

.dp-row {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 2px 0;
}

.dp-row .dp-bar {
  height: 14px;
  background: var(--accent);
  border-radius: 3px;
  transition: width 0.3s, background 0.3s;
}

.dp-row .dp-bar.winner { background: var(--gold); }
.dp-row .dp-label { width: 50px; color: var(--dim); }
.dp-row .dp-score { width: 60px; text-align: right; }
.dp-row .dp-weight { width: 70px; text-align: right; color: var(--green); }

#readResult {
  margin-top: 1rem;
  padding: 0.8rem 1rem;
  background: rgba(255, 213, 79, 0.1);
  border-radius: 8px;
  border-left: 3px solid var(--gold);
  font-family: monospace;
  font-size: 0.9rem;
}

/* Side-by-side comparison */
.sbs-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin: 1rem 0;
}

.sbs-panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1rem;
  overflow-x: auto;
}

.sbs-header {
  font-size: 0.9rem;
  font-weight: 700;
  margin-bottom: 4px;
  padding-bottom: 6px;
  border-bottom: 2px solid var(--border);
}

.sbs-header.trad { color: var(--accent2); border-color: var(--accent2); }
.sbs-header.lookup { color: var(--gold); border-color: var(--gold); }

.sbs-subtitle {
  font-size: 0.72rem;
  color: var(--dim);
  margin-bottom: 0.8rem;
}

.sbs-vec-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 0.8rem;
}

.sbs-keys {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  margin-bottom: 0.8rem;
}

.sbs-key-group {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  padding: 6px 4px;
  border-radius: 6px;
  min-width: 58px;
  transition: background 0.2s;
}

.sbs-key-group.winner { background: rgba(255, 213, 79, 0.1); }
.sbs-key-group.trad-winner { background: rgba(171, 71, 188, 0.1); }

.sbs-key-group .sbs-word {
  font-size: 0.7rem;
  color: var(--dim);
  font-style: italic;
}

.sbs-key-group .sbs-score {
  font-family: monospace;
  font-size: 0.75rem;
  color: var(--text);
}

.sbs-key-group .sbs-weight {
  font-family: monospace;
  font-size: 0.78rem;
  font-weight: 600;
}

.sbs-key-group.winner .sbs-weight { color: var(--gold); }
.sbs-key-group.trad-winner .sbs-weight { color: var(--accent2); }

.sbs-weight-bar {
  height: 4px;
  border-radius: 2px;
  transition: width 0.3s;
  margin-top: 1px;
}

.sbs-key-group .sbs-weight-bar { background: var(--accent); }
.sbs-key-group.winner .sbs-weight-bar { background: var(--gold); }
.sbs-key-group.trad-winner .sbs-weight-bar { background: var(--accent2); }

.sbs-result {
  font-size: 0.82rem;
  padding: 0.5rem 0.7rem;
  background: var(--surface2);
  border-radius: 6px;
  margin-bottom: 0.6rem;
  font-family: monospace;
  line-height: 1.6;
}

.sbs-note {
  font-size: 0.78rem;
  color: var(--dim);
  line-height: 1.5;
}

.sbs-note strong { color: var(--text); }

.sbs-controls {
  margin-bottom: 0.5rem;
}

/* Small column vec variant for SBS */
.col-vec.sbs-vec .cell {
  font-size: 0.78rem;
  padding: 2px 8px;
  min-width: 36px;
}

.col-vec.sbs-vec .vec-label {
  font-size: 0.65rem;
}

@media (max-width: 768px) {
  .sbs-container { grid-template-columns: 1fr; }
}

/* Write-read trace demo */
.write-read-demo {
  margin-top: 0.6rem;
}

.wr-trace {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  margin-bottom: 0.8rem;
  min-height: 90px;
  align-items: flex-start;
}

.wr-token {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  padding: 6px 8px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--surface);
  min-width: 70px;
  transition: all 0.3s;
  position: relative;
}

.wr-token.new-token {
  animation: wrFlash 0.6s ease;
}

.wr-token.reading {
  border-color: var(--warn);
  box-shadow: 0 0 8px rgba(255, 112, 67, 0.3);
}

.wr-token.found {
  border-color: var(--gold);
  background: rgba(255, 213, 79, 0.1);
  box-shadow: 0 0 8px rgba(255, 213, 79, 0.3);
}

.wr-token.shadowed {
  opacity: 0.35;
}

@keyframes wrFlash {
  0% { background: rgba(102, 187, 106, 0.25); }
  100% { background: var(--surface); }
}

.wr-token .wr-tok-label {
  font-size: 0.65rem;
  color: var(--dim);
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.wr-token .wr-tok-instr {
  font-family: monospace;
  font-size: 0.75rem;
  color: var(--text);
  font-weight: 600;
}

.wr-token .wr-tok-kv {
  font-family: monospace;
  font-size: 0.65rem;
  line-height: 1.4;
}

.wr-tok-kv .wr-k { color: var(--accent); }
.wr-tok-kv .wr-v { color: var(--green); }

.wr-read-arrow {
  position: absolute;
  top: -18px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 0.65rem;
  color: var(--warn);
  font-weight: 600;
  white-space: nowrap;
}

.wr-action {
  padding: 0.6rem 0.8rem;
  background: var(--surface2);
  border-radius: 8px;
  font-size: 0.82rem;
  line-height: 1.6;
  min-height: 50px;
  color: var(--text);
}

.wr-action .wr-step-title {
  font-weight: 600;
  color: var(--gold);
  margin-bottom: 2px;
}

/* Attention flow diagram */
.attn-flow-diagram {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin: 0.8rem 0;
}

.attn-flow-section {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.attn-flow-label {
  font-size: 0.7rem;
  color: var(--dim);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  font-weight: 600;
  margin-top: 4px;
}

.attn-flow-row {
  display: flex;
  align-items: center;
  gap: 10px;
  padding-left: 12px;
}

.attn-flow-box {
  font-family: monospace;
  font-size: 0.85rem;
  padding: 0.3rem 0.7rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--surface);
  color: var(--text);
  white-space: nowrap;
}

.attn-flow-box.computed {
  border-color: var(--dim);
  border-style: dashed;
  color: var(--dim);
}

.attn-flow-desc {
  font-size: 0.75rem;
  color: var(--dim);
  line-height: 1.4;
}

.attn-flow-desc strong { color: var(--gold); }

/* Token pipeline diagram */
.pipeline-diagram {
  display: flex;
  align-items: center;
  gap: 0;
  margin: 0.8rem 0;
  flex-wrap: wrap;
  justify-content: center;
}

.pipe-step {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 3px;
}

.pipe-label {
  font-size: 0.7rem;
  color: var(--dim);
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.pipe-box {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0.4rem 0.8rem;
  font-family: monospace;
  font-size: 0.9rem;
  color: var(--text);
}

.pipe-box.pipe-text { color: var(--gold); font-style: italic; }
.pipe-box.pipe-id { color: var(--accent); }
.pipe-box.pipe-emb { font-size: 0.8rem; color: var(--green); }

.pipe-dim {
  font-size: 0.65rem;
  color: var(--dim);
  font-style: italic;
}

.pipe-arrow {
  font-size: 1.1rem;
  color: var(--dim);
  padding: 0 0.6rem;
  text-align: center;
  line-height: 1.2;
}

.pipe-arrow-label {
  font-size: 0.65rem;
  color: var(--dim);
}

/* QKV matrix multiply diagram */
.qkv-matmul-diagram {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin: 0.6rem 0;
}

.qkv-row {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 4px 0;
}

.qkv-input {
  font-family: monospace;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text);
  min-width: 20px;
  text-align: center;
}

.qkv-times {
  font-size: 0.9rem;
  color: var(--dim);
}

.qkv-matrix {
  font-family: monospace;
  font-size: 0.9rem;
  font-weight: 600;
  padding: 0.25rem 0.6rem;
  border: 2px solid;
  border-radius: 6px;
  background: var(--surface2);
  min-width: 40px;
  text-align: center;
}

.qkv-eq {
  font-size: 0.9rem;
  color: var(--dim);
}

.qkv-output {
  font-family: monospace;
  font-size: 1rem;
  font-weight: 700;
  min-width: 20px;
  text-align: center;
}

.qkv-meaning {
  font-size: 0.78rem;
  color: var(--dim);
  margin-left: 4px;
}

/* Query origin visualization */
.query-origin-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-top: 0.8rem;
}

.qo-panel {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1rem;
}

.qo-header {
  font-weight: 700;
  font-size: 0.9rem;
  margin-bottom: 0.7rem;
  padding-bottom: 5px;
  border-bottom: 1px solid var(--border);
}

.qo-pipeline {
  display: flex;
  flex-direction: column;
  gap: 2px;
  align-items: center;
  margin-bottom: 0.7rem;
}

.qo-step {
  width: 100%;
  text-align: center;
}

.qo-label {
  font-size: 0.7rem;
  color: var(--dim);
  margin-bottom: 2px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.qo-box {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0.4rem 0.6rem;
  font-size: 0.82rem;
  color: var(--text);
}

.qo-box code {
  color: var(--gold);
  font-size: 0.8rem;
}

.qo-box.learned {
  border-color: var(--accent2);
  color: var(--accent2);
  font-weight: 600;
  font-size: 0.85rem;
}

.qo-box.engineered {
  border-color: var(--gold);
  color: var(--gold);
  font-weight: 600;
  font-size: 0.85rem;
}

.qo-dim {
  font-size: 0.68rem;
  color: var(--dim);
  margin-top: 2px;
  font-style: italic;
}

.qo-arrow {
  font-size: 0.85rem;
  color: var(--dim);
  padding: 2px 0;
  font-family: monospace;
}

.qo-note {
  font-size: 0.78rem;
  color: var(--dim);
  line-height: 1.5;
  margin-top: 0.4rem;
}

.qo-note strong { color: var(--text); }
.qo-note em { color: var(--gold); font-style: normal; }

@media (max-width: 768px) {
  .query-origin-grid { grid-template-columns: 1fr; }
}

/* KQV explanation table */
.kqv-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0 6px;
  margin-top: 0.5rem;
}

.kqv-table td {
  padding: 0.6rem 0.8rem;
  background: var(--surface2);
  font-size: 0.85rem;
  vertical-align: top;
}

.kqv-table tr td:first-child {
  border-radius: 6px 0 0 6px;
}

.kqv-table tr td:last-child {
  border-radius: 0 6px 6px 0;
}

.kqv-name {
  font-weight: 700;
  font-size: 0.9rem;
  white-space: nowrap;
  width: 70px;
}

/* Column vector displays (tab 2) */
#queryVec {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 0.5rem;
}

.col-vec {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  position: relative;
}

.col-vec .bracket {
  position: absolute;
  top: 0; bottom: 0;
  width: 6px;
  border: 2px solid var(--accent);
  border-right: none;
  border-radius: 4px 0 0 4px;
  left: -10px;
}

.col-vec .bracket-r {
  position: absolute;
  top: 0; bottom: 0;
  width: 6px;
  border: 2px solid var(--accent);
  border-left: none;
  border-radius: 0 4px 4px 0;
  right: -10px;
}

.col-vec.query .bracket,
.col-vec.query .bracket-r { border-color: var(--warn); }

.col-vec.winner .bracket,
.col-vec.winner .bracket-r { border-color: var(--gold); }

.col-vec .cell {
  font-family: monospace;
  font-size: 0.95rem;
  padding: 4px 14px;
  text-align: right;
  min-width: 48px;
  color: var(--text);
}

.col-vec.query .cell { color: var(--warn); font-weight: 600; }
.col-vec.winner .cell { color: var(--gold); font-weight: 600; }

.vec-label {
  font-size: 0.72rem;
  color: var(--dim);
  text-align: center;
  margin-top: 4px;
}

.col-vec.winner .vec-label { color: var(--gold); }

#vecColumns {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  align-items: flex-start;
  margin-bottom: 1rem;
}

.vec-group {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  padding: 8px 6px;
  border-radius: 8px;
  transition: background 0.2s;
  min-width: 72px;
}

.vec-group.winner { background: rgba(255, 213, 79, 0.08); }

.dot-product-line {
  display: flex;
  align-items: center;
  gap: 6px;
  font-family: monospace;
  font-size: 0.78rem;
  margin-top: 4px;
  color: var(--dim);
}

.dot-product-line .dp-val {
  font-weight: 600;
  color: var(--accent);
}

.vec-group.winner .dot-product-line .dp-val { color: var(--gold); }

.dot-product-line .dp-weight {
  font-size: 0.72rem;
  color: var(--green);
}

.dp-bar-mini {
  height: 4px;
  border-radius: 2px;
  background: var(--accent);
  transition: width 0.3s;
  margin-top: 2px;
}

.vec-group.winner .dp-bar-mini { background: var(--gold); }

.dot-computation {
  font-family: monospace;
  font-size: 0.75rem;
  color: var(--dim);
  margin-top: 2px;
  text-align: center;
  line-height: 1.5;
}

/* Two column layout */
.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

canvas {
  background: var(--surface);
  border-radius: 8px;
  border: 1px solid var(--border);
  width: 100%;
  height: auto;
}

/* Mechanism grid (tab 4) */
.mechanism-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.mechanism {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem;
}

.mechanism h3 {
  font-size: 0.95rem;
  color: var(--gold);
  margin-bottom: 0.5rem;
}

.mechanism p {
  font-size: 0.8rem;
  margin-bottom: 0.4rem;
}

.mechanism strong { color: var(--accent); font-size: 0.78rem; }

/* Stack machine vis */
#stackMachineVis {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 1rem;
  margin-bottom: 1rem;
}

#smProgram, #smState, #smHeads {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.8rem;
  min-height: 200px;
}

#smProgram h4, #smState h4, #smHeads h4 {
  font-size: 0.78rem;
  color: var(--dim);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.6rem;
}

.instr-line {
  font-family: monospace;
  font-size: 0.8rem;
  padding: 2px 6px;
  border-radius: 4px;
  margin-bottom: 2px;
}

.instr-line.current {
  background: rgba(79, 195, 247, 0.15);
  color: var(--accent);
  font-weight: 600;
}

.instr-line.done { color: var(--dim); }

.state-row {
  display: flex;
  justify-content: space-between;
  font-size: 0.82rem;
  padding: 3px 0;
  border-bottom: 1px solid var(--border);
}

.state-row .label { color: var(--dim); }
.state-row .value { font-family: monospace; color: var(--gold); font-weight: 600; }

.stack-item {
  font-family: monospace;
  font-size: 0.85rem;
  padding: 3px 8px;
  background: rgba(79, 195, 247, 0.1);
  border-radius: 4px;
  margin-bottom: 3px;
  text-align: center;
}

.stack-item.top { background: rgba(255, 213, 79, 0.15); color: var(--gold); }

.head-info {
  font-size: 0.75rem;
  margin-bottom: 0.5rem;
  padding: 0.4rem 0.5rem;
  background: var(--surface2);
  border-radius: 6px;
}

.head-info .head-name { color: var(--accent2); font-weight: 600; }
.head-info .head-action { color: var(--text); }
.head-info .head-detail { color: var(--dim); font-family: monospace; font-size: 0.72rem; }

/* Buttons */
.btn-row {
  display: flex;
  gap: 8px;
  margin-top: 0.5rem;
}

.action-btn {
  background: var(--accent);
  color: var(--bg);
  border: none;
  padding: 0.5rem 1.2rem;
  border-radius: 6px;
  font-weight: 600;
  cursor: pointer;
  font-size: 0.85rem;
  transition: all 0.2s;
}

.action-btn:hover { filter: brightness(1.15); }
.action-btn.secondary {
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
}

.next-btn {
  display: block;
  margin: 1.5rem auto 0;
  background: none;
  border: 1px solid var(--accent);
  color: var(--accent);
  padding: 0.6rem 1.5rem;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.9rem;
  transition: all 0.2s;
}

.next-btn:hover { background: var(--accent); color: var(--bg); }

/* Full execution (tab 5) */
#fullExec {
  display: grid;
  grid-template-columns: 200px 1fr 1fr;
  gap: 1rem;
  margin-bottom: 1rem;
}

#feProgram, #feTrace, #feDetail {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.8rem;
  min-height: 260px;
}

#feProgram h4, #feTrace h4, #feDetail h4 {
  font-size: 0.78rem;
  color: var(--dim);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.6rem;
}

.trace-token {
  font-family: monospace;
  font-size: 0.8rem;
  padding: 3px 8px;
  margin-bottom: 2px;
  border-radius: 4px;
  display: flex;
  justify-content: space-between;
}

.trace-token.new {
  background: rgba(255, 213, 79, 0.12);
  animation: flashIn 0.5s ease;
}

@keyframes flashIn {
  0% { background: rgba(255, 213, 79, 0.4); }
  100% { background: rgba(255, 213, 79, 0.12); }
}

.trace-token .tok { color: var(--text); }
.trace-token .meta { color: var(--dim); font-size: 0.72rem; }

/* Comparison */
.comparison {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-top: 0.8rem;
}

.comp-col {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1rem;
}

.comp-col.highlight {
  border-color: var(--accent);
  background: rgba(79, 195, 247, 0.05);
}

.comp-col h4 {
  font-size: 0.95rem;
  margin-bottom: 0.6rem;
}

.comp-col p {
  font-size: 0.82rem;
  margin-bottom: 0.3rem;
}

/* Summary grid */
.summary-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.8rem;
  margin: 1rem 0;
}

.summary-item {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.8rem 1rem;
  font-size: 0.85rem;
}

.summary-item strong { color: var(--gold); }
.summary-item .dim { color: var(--dim); font-size: 0.78rem; }

/* IP demo */
.ip-trace {
  display: flex;
  gap: 4px;
  flex-wrap: wrap;
}

.ip-cell {
  background: var(--surface2);
  border-radius: 4px;
  padding: 2px 6px;
  font-family: monospace;
  font-size: 0.7rem;
  text-align: center;
  min-width: 36px;
}

.ip-cell .delta { color: var(--green); }
.ip-cell .sum { color: var(--gold); font-weight: 600; }

/* Stack vis */
.stack-vis {
  display: flex;
  flex-direction: column-reverse;
  gap: 3px;
  max-height: 100px;
}

.sv-item {
  background: rgba(79, 195, 247, 0.12);
  border-radius: 4px;
  padding: 2px 8px;
  font-family: monospace;
  font-size: 0.75rem;
  text-align: center;
}

/* Responsive */
@media (max-width: 768px) {
  .mechanism-grid { grid-template-columns: 1fr; }
  #stackMachineVis { grid-template-columns: 1fr; }
  #fullExec { grid-template-columns: 1fr; }
  .two-col { grid-template-columns: 1fr; }
  .comparison { grid-template-columns: 1fr; }
  .summary-grid { grid-template-columns: 1fr; }
  .vec-vis-container { grid-template-columns: 1fr; }
  #tabs { flex-wrap: wrap; }
}