/* ============================================================ */
/* Lab 03 — per-lab styles (nanochat on Rivanna)                  */
/* ============================================================ */

/* .callout.warn — amber warning variant (disk/time cautions).
   Base .callout + .insight/.note live in _shared/lab-base.css;
   this is purely additive. */
.callout.warn {
  background: #fdf3e3;
  border-left: 3px solid #d9a441;
}

/* Match code-block font to body paragraph (18px) — overrides
   the 14px default in _shared/lab-base.css for this lab only. */
pre code { font-size: 18px; line-height: 1.55; }

.course-frame {
  font-family: var(--serif); font-size: 17px; line-height: 1.65;
  color: var(--ink-soft); margin: 10px 0 24px 0;
  padding: 6px 0 6px 16px; border-left: 3px solid var(--accent-soft);
}
.course-frame strong { color: var(--ink); }
body.presentation-mode .course-frame {
  font-size: 22px; padding-left: 22px; margin: 14px 0 32px 0;
}

.time-tag {
  display: inline-block; margin-left: 10px; padding: 2px 8px;
  font-family: var(--sans); font-size: 11px; font-weight: 500;
  text-transform: none; letter-spacing: 0; color: var(--ink-mute);
  background: var(--bg-elev); border: 1px solid var(--rule);
  border-radius: 10px; vertical-align: 2px;
}

pre.term-snippet {
  background: #14110d; color: #e8e1d5;
  font-family: var(--mono); font-size: 12.5px; line-height: 1.5;
  padding: 14px 16px; border-radius: 6px;
  overflow-x: auto; white-space: pre; margin: 6px 0 12px 0;
}
pre.term-snippet .term-comment      { color: #6fab5c; }
pre.term-snippet .term-cmd          { color: #f9d57c; font-weight: 700; }   /* what the user types */
pre.term-snippet .term-prompt-echo  { color: #b2d3e8; }
pre.term-snippet .term-hl { background: rgba(177,74,46,0.28); color: #ffd8c4; padding: 0 3px; border-radius: 2px; }

/* ============================================================ */
/* .annotated-term — terminal snippet with hover-per-line        */
/* explanations. Same shape as Lab 02's .annotated-code, dark    */
/* palette to match .term-snippet.                               */
/* ============================================================ */
.annotated-term {
  background: #14110d; color: #e8e1d5;
  font-family: var(--mono); font-size: 12.5px; line-height: 1.55;
  padding: 12px 0; border-radius: 6px;
  overflow: hidden; margin: 6px 0 0 0;
}
.annotated-term .term-step {
  padding: 1px 16px;
  white-space: pre;
  border-left: 3px solid transparent;
  transition: background 100ms, border-left-color 100ms;
}
.annotated-term .term-step[data-explain] {
  cursor: help;
  outline: none;
}
.annotated-term .term-step[data-explain]:hover,
.annotated-term .term-step[data-explain]:focus,
.annotated-term .term-step.active {
  background: rgba(249, 213, 124, 0.10);
  border-left-color: #f9d57c;
}
.annotated-term .term-prompt     { color: #6fab5c; user-select: none; }
.annotated-term .term-cmd        { color: #f9d57c; font-weight: 700; }
.annotated-term .term-output     { color: #b8b1a1; }
.annotated-term .term-output-num { color: #f6efe1; font-weight: 600; }
.annotated-term .term-comment    { color: #6fab5c; font-style: italic; }
.annotated-term .term-hl         { background: rgba(177,74,46,0.28); color: #ffd8c4;
                                   padding: 0 3px; border-radius: 2px; }

.term-explain-panel {
  margin: 10px 0 12px;
  background: var(--bg-elev); border: 1px solid var(--rule);
  border-left: 3px solid var(--accent-soft); border-radius: 0 4px 4px 0;
  padding: 10px 14px;
  font-family: var(--serif); font-size: 13.5px; line-height: 1.55;
  color: var(--ink-soft);
}
.term-explain-tag {
  display: inline-block;
  font-family: var(--sans); font-size: 10px; font-weight: 700;
  letter-spacing: 0.1em; text-transform: uppercase;
  color: var(--accent);
  background: white; padding: 2px 8px; border-radius: 3px;
  margin-right: 8px; vertical-align: 1px;
}
.term-explain-text { display: inline; }
.term-explain-text code {
  background: white; color: #5a3a30; padding: 1px 5px;
  border-radius: 3px; font-size: 0.92em;
}
.term-explain-text strong { color: var(--ink); }

/* Practice list */
.practice {
  display: flex; gap: 14px; align-items: flex-start;
  margin: 12px 0; padding: 12px 16px 12px 12px;
  background: var(--bg-elev); border-radius: 6px;
  border-left: 3px solid var(--accent-soft);
}
.practice-num {
  flex-shrink: 0; width: 28px; height: 28px;
  font-family: var(--mono); font-size: 13px; font-weight: 700;
  display: inline-flex; align-items: center; justify-content: center;
  background: var(--accent); color: white; border-radius: 50%;
}
.practice strong { color: var(--ink); }

/* Figure with caption (screenshots) — placeholder-friendly */
figure.lab-figure {
  margin: 14px 0 22px 0;
  padding: 0;
  background: var(--bg-elev);
  border: 1px solid var(--rule);
  border-radius: 8px;
  overflow: hidden;
}
figure.lab-figure img {
  display: block;
  max-width: 100%;
  height: auto;
  min-height: 140px;
  background: #f0eee5;     /* visible plate while loading / if missing */
}
figure.lab-figure figcaption {
  font-family: var(--sans);
  font-size: 13px;
  line-height: 1.5;
  color: var(--ink-mute);
  padding: 9px 14px 10px;
  border-top: 1px solid var(--rule);
}
figure.lab-figure figcaption strong { color: var(--ink); }
figure.lab-figure figcaption code {
  background: var(--bg-code); padding: 1px 5px; border-radius: 3px;
  font-family: var(--mono); font-size: 0.92em;
}

/* ============================================================ */
/*  Widget · five-phase pipeline timeline                         */
/* ============================================================ */
.pipeline-svg {
  display: block;
  width: 100%;
  max-width: 720px;
  height: auto;
  margin: 0 auto;
  background: var(--bg-elev);
  border-radius: 6px;
  border: 1px solid var(--rule);
}
.pipeline-svg .phase-band {
  fill: var(--bg-viz);
}
.pipeline-svg .phase-chip {
  fill: var(--bg-viz);
  stroke: var(--rule);
  stroke-width: 1;
  cursor: pointer;
  transition: fill 0.1s, stroke 0.1s, stroke-width 0.1s;
}
.pipeline-svg .phase-chip:hover,
.pipeline-svg .phase-chip.active {
  fill: var(--accent-soft);
  stroke: var(--accent);
  stroke-width: 1.6;
}
.pipeline-svg .phase-chip.optional {
  stroke-dasharray: 4 3;
}
.pipeline-svg .phase-num {
  font-family: var(--mono); font-size: 11px;
  fill: var(--ink-mute); text-anchor: middle;
}
.pipeline-svg .phase-name {
  font-family: var(--sans); font-size: 13px; font-weight: 600;
  fill: var(--ink); text-anchor: middle; pointer-events: none;
}
.pipeline-svg .phase-arrow {
  stroke: var(--ink-mute); stroke-width: 1;
  fill: none; opacity: 0.5;
}
.pipeline-svg .phase-tag {
  font-family: var(--mono); font-size: 10px;
  fill: var(--ink-mute); text-anchor: middle;
}

.pipeline-detail {
  margin-top: 12px;
  padding: 14px 18px;
  background: var(--bg-elev);
  border-left: 3px solid var(--accent);
  border-radius: 0 6px 6px 0;
  font-family: var(--serif);
  font-size: 14.5px;
  line-height: 1.55;
  color: var(--ink);
  min-height: 6em;
}
.pipeline-detail .phase-detail-title {
  font-family: var(--sans); font-size: 11px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.08em;
  color: var(--ink-mute); margin-bottom: 6px;
}
.pipeline-detail .phase-detail-section {
  font-family: var(--sans); font-size: 11px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.06em;
  color: var(--accent); margin-top: 8px;
}
.pipeline-detail code {
  font-family: var(--mono); font-size: 0.92em;
  background: var(--bg-code); padding: 1px 5px; border-radius: 3px;
}

/* ============================================================
   BPE merge stepper · #viz-bpe
   ============================================================ */
.bpe-controls {
  display: flex; align-items: center; gap: 10px;
  flex-wrap: wrap; margin: 14px 0 18px;
}
.bpe-counter {
  font-family: var(--mono); font-size: 0.9rem;
  color: var(--ink-mute); margin-left: auto;
}
.bpe-counter strong { color: var(--ink); }
.bpe-grid {
  display: grid; grid-template-columns: 1.4fr 1fr;
  gap: 16px; margin-bottom: 14px;
}
@media (max-width: 760px) {
  .bpe-grid { grid-template-columns: 1fr; }
}
.bpe-panel {
  padding: 12px 14px;
  background: #faf8f2;
  border: 1px solid #e6e2d6;
  border-radius: 6px;
  margin-bottom: 14px;
}
.bpe-grid .bpe-panel { margin-bottom: 0; }
.bpe-panel-title {
  font-family: var(--sans); font-size: 11px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.06em;
  color: var(--ink-mute); margin-bottom: 10px;
}
.bpe-corpus { display: flex; flex-direction: column; gap: 7px; }
.bpe-word { display: flex; align-items: center; gap: 4px; flex-wrap: wrap; }
.bpe-word-count {
  min-width: 30px;
  font-family: var(--mono); font-size: 0.82rem;
  color: var(--ink-mute); margin-right: 4px;
}
.bpe-tok {
  display: inline-block;
  padding: 2px 7px;
  background: white;
  border: 1px solid #c7c3b5;
  border-radius: 3px;
  font-family: var(--mono); font-size: 0.92rem;
  color: var(--ink);
  transition: background 200ms, border-color 200ms;
}
.bpe-tok.bpe-tok-pair { background: #ffe6cf; border-color: #c97a3f; }
.bpe-tok.bpe-tok-new { background: #fde0d2; border-color: var(--accent); font-weight: 700; }
.bpe-pairs-table {
  width: 100%; border-collapse: collapse;
  font-family: var(--mono); font-size: 0.88rem;
}
.bpe-pairs-table td {
  padding: 4px 8px; border-bottom: 1px solid #ede9dc;
}
.bpe-pairs-table tr:last-child td { border-bottom: none; }
.bpe-pairs-table tr.bpe-pair-winner td {
  background: #fde0d2; color: var(--ink); font-weight: 600;
}
.bpe-pairs-table td:last-child { text-align: right; color: var(--ink-mute); }
.bpe-pairs-table tr.bpe-pair-winner td:last-child { color: var(--accent); font-weight: 700; }
.bpe-vocab { display: flex; flex-wrap: wrap; gap: 4px; }
.bpe-vocab .bpe-tok { font-size: 0.82rem; padding: 1px 6px; }
.bpe-vocab-count {
  display: inline-block;
  font-family: var(--mono);
  background: var(--ink); color: white;
  padding: 1px 7px; border-radius: 3px;
  font-size: 0.78rem; margin-left: 4px;
  vertical-align: 2px;
}

/* ============================================================
   SFT side-by-side · #viz-sft
   ============================================================ */
.sft-controls {
  display: flex; align-items: center; gap: 10px;
  flex-wrap: wrap; margin: 14px 0 14px;
}
.sft-example-label {
  font-family: var(--mono); font-size: 0.88rem;
  color: var(--ink-mute);
  display: inline-flex; align-items: center; gap: 4px;
}
.sft-example-label strong { color: var(--ink); }
.sft-arrow {
  background: none; border: 1px solid #c7c3b5;
  border-radius: 3px; padding: 0 7px;
  font-size: 0.95rem; line-height: 1.4;
  cursor: pointer; color: var(--ink);
  font-family: var(--mono);
}
.sft-arrow:hover { background: #ede9dc; }
.sft-caption-mini {
  font-family: var(--serif); font-size: 0.85rem;
  color: var(--ink-mute); font-style: italic;
  margin-left: auto;
}
.sft-prompt {
  padding: 10px 14px;
  background: #f4eee0;
  border: 1px solid #e1d9be;
  border-radius: 6px;
  margin-bottom: 12px;
  font-family: var(--mono); font-size: 0.9rem;
}
.sft-prompt-label {
  font-family: var(--sans); font-size: 10px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.08em;
  color: var(--ink-mute); margin-bottom: 5px;
}
.sft-prompt-body { color: var(--ink); line-height: 1.45; }
.sft-grid {
  display: grid; grid-template-columns: 1fr 1fr;
  gap: 14px; margin-bottom: 12px;
}
@media (max-width: 760px) {
  .sft-grid { grid-template-columns: 1fr; }
}
.sft-panel {
  background: #faf8f2;
  border: 1px solid #e6e2d6;
  border-radius: 6px;
  padding: 12px 14px;
  display: flex; flex-direction: column;
  min-height: 200px;
}
.sft-panel-head {
  display: flex; align-items: baseline; gap: 8px;
  margin-bottom: 8px; padding-bottom: 7px;
  border-bottom: 1px dashed #d8d2c0;
}
.sft-panel-tag {
  font-family: var(--sans); font-size: 11px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.06em;
  padding: 2px 7px; border-radius: 3px;
}
.sft-tag-base { background: #e8e0cd; color: #5a4e2f; }
.sft-tag-sft  { background: #d5e6dc; color: #2f5a47; }
.sft-panel-sub {
  font-family: var(--serif); font-size: 0.82rem;
  color: var(--ink-mute); font-style: italic;
}
.sft-stream {
  font-family: var(--mono); font-size: 0.9rem;
  line-height: 1.55; color: var(--ink);
  flex: 1; white-space: pre-wrap; word-break: break-word;
  min-height: 110px;
}
.sft-stream .sft-tok {
  display: inline; transition: background 250ms;
}
.sft-stream .sft-tok-new {
  background: #fde0d2;
}
.sft-stream .sft-special {
  display: inline-block;
  font-family: var(--mono); font-size: 0.78rem;
  padding: 1px 5px; margin: 0 1px;
  border-radius: 3px; background: #d5e6dc;
  border: 1px solid #9bc0ad; color: #2f5a47;
  font-weight: 600;
  white-space: nowrap;
  vertical-align: 1px;
}
.sft-stream .sft-special.sft-special-end {
  background: var(--accent); color: white; border-color: var(--accent);
}
.sft-stream .sft-drift { color: #b14a2e; font-style: italic; }
.sft-failure {
  font-family: var(--serif); font-size: 0.85rem;
  color: #8a4a2e; font-style: italic;
  margin-top: 10px; padding-top: 8px;
  border-top: 1px dashed #d8d2c0;
  min-height: 1.2em;
}
.sft-failure.sft-failure-good { color: #2f5a47; }

/* ============================================================
   GRPO one-step diagram · #viz-grpo
   ============================================================ */
.grpo-controls {
  display: flex; align-items: center; gap: 10px;
  flex-wrap: wrap; margin: 14px 0;
}
.grpo-example-label {
  font-family: var(--mono); font-size: 0.88rem;
  color: var(--ink-mute);
  display: inline-flex; align-items: center; gap: 4px;
}
.grpo-example-label strong { color: var(--ink); }
.grpo-task-tag {
  font-family: var(--sans); font-size: 10px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.06em;
  padding: 3px 9px; border-radius: 3px;
  background: #ede9dc; color: var(--ink-soft);
  margin-left: auto;
}
.grpo-prompt {
  padding: 10px 14px;
  background: #f4eee0;
  border: 1px solid #e1d9be;
  border-radius: 6px;
  margin-bottom: 12px;
}
.grpo-prompt-label {
  font-family: var(--sans); font-size: 10px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.08em;
  color: var(--ink-mute); margin-bottom: 5px;
}
.grpo-prompt-body {
  font-family: var(--mono); font-size: 0.92rem;
  color: var(--ink);
}
.grpo-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  margin-bottom: 14px;
}
@media (max-width: 760px) {
  .grpo-grid { grid-template-columns: 1fr; }
}
.grpo-card {
  position: relative;
  background: #faf8f2;
  border: 1px solid #e6e2d6;
  border-left: 4px solid #c7c3b5;
  border-radius: 5px;
  padding: 10px 14px 12px;
  transition: border-left-color 250ms, background 250ms;
}
.grpo-card.grpo-pos { border-left-color: #2f8557; background: #f2f8f4; }
.grpo-card.grpo-neg { border-left-color: var(--accent); background: #fbf2ee; }
.grpo-card-head {
  display: flex; align-items: baseline;
  gap: 8px; margin-bottom: 6px;
}
.grpo-sample-no {
  font-family: var(--sans); font-size: 10px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.06em;
  color: var(--ink-mute);
}
.grpo-reward {
  font-family: var(--mono); font-size: 0.85rem;
  margin-left: auto; padding: 1px 7px; border-radius: 3px;
  background: #ede9dc; color: var(--ink-soft);
}
.grpo-reward.grpo-reward-pass { background: #d5e6dc; color: #2f5a47; font-weight: 700; }
.grpo-reward.grpo-reward-fail { background: #f2d9cf; color: #8a3a1f; font-weight: 700; }
.grpo-completion {
  font-family: var(--mono); font-size: 0.86rem;
  color: var(--ink); line-height: 1.5;
  white-space: pre-wrap; min-height: 2.4em;
  margin-bottom: 8px;
}
.grpo-advantage-row {
  display: flex; align-items: center; gap: 10px;
  font-family: var(--mono); font-size: 0.82rem;
  color: var(--ink-mute);
}
.grpo-adv-bar {
  flex: 1;
  position: relative;
  height: 8px;
  background: #ede9dc;
  border-radius: 4px;
}
.grpo-adv-bar::before {
  content: "";
  position: absolute;
  left: 50%; top: -3px; bottom: -3px;
  width: 1px; background: var(--ink-mute);
}
.grpo-adv-fill {
  position: absolute; top: 0; bottom: 0;
  background: #2f8557; border-radius: 4px;
}
.grpo-adv-fill.grpo-neg-fill { background: var(--accent); }
.grpo-adv-num {
  min-width: 56px; text-align: right;
  font-variant-numeric: tabular-nums;
}
.grpo-adv-num.grpo-pos-num { color: #2f8557; font-weight: 700; }
.grpo-adv-num.grpo-neg-num { color: var(--accent); font-weight: 700; }
.grpo-verdict {
  font-family: var(--sans); font-size: 11px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.06em;
  margin-top: 7px;
}
.grpo-verdict.grpo-pos { color: #2f8557; }
.grpo-verdict.grpo-neg { color: var(--accent); }
.grpo-summary {
  padding: 10px 14px;
  background: #faf8f2;
  border: 1px solid #e6e2d6;
  border-radius: 6px;
  font-family: var(--mono); font-size: 0.88rem;
  color: var(--ink);
  display: flex; gap: 18px; flex-wrap: wrap;
  align-items: center;
}
.grpo-summary .grpo-summary-kv { color: var(--ink-mute); }
.grpo-summary .grpo-summary-kv strong {
  color: var(--ink); font-weight: 700;
  margin-left: 4px;
}

/* ============================================================ */
/* #viz-residual — "what is a residual position?"                */
/* ============================================================ */
#viz-residual { padding: 16px 18px; }

/* Bridge panel · "Lab 02 · one column → Lab 03 · column per token" */
.rp-bridge {
  display: grid;
  grid-template-columns: minmax(140px, 200px) 56px 1fr;
  gap: 14px;
  align-items: center;
  background: #fffaef;
  border: 1px solid #e7d9a8;
  border-left: 3px solid var(--accent);
  border-radius: 5px;
  padding: 14px 16px;
  margin: 6px 0 16px;
}
@media (max-width: 720px) {
  .rp-bridge {
    grid-template-columns: 1fr;
  }
  .rp-bridge-arrow { display: none; }
}
.rp-bridge-left, .rp-bridge-right {
  display: flex; flex-direction: column; gap: 8px;
}
.rp-bridge-left { align-items: center; text-align: center; }
.rp-bridge-label {
  font-family: var(--sans); font-size: 10px; font-weight: 700;
  letter-spacing: 0.1em; text-transform: uppercase;
  color: var(--accent);
}
.rp-bridge-svg {
  display: flex; justify-content: center;
}
.rp-bridge-caption {
  font-family: var(--serif); font-size: 13px; line-height: 1.5;
  color: var(--ink-soft);
}
.rp-bridge-caption strong { color: var(--ink); }
.rp-bridge-arrow {
  font-family: var(--mono); font-size: 12px;
  color: var(--accent); font-weight: 700;
  text-align: center; line-height: 1.4;
}

/* Toggle ----------------------------------------------------- */
.rp-toggle {
  display: flex; gap: 8px; flex-wrap: wrap; align-items: center;
  margin: 4px 0 16px;
}
.rp-toggle-label {
  font-family: var(--sans); font-size: 11px;
  text-transform: uppercase; letter-spacing: 0.08em;
  color: var(--ink-mute); margin-right: 2px;
}
.rp-toggle .btn-mini {
  font-family: var(--mono); font-size: 12px;
  background: var(--bg-elev); border: 1px solid var(--rule);
  color: var(--ink-soft);
  padding: 6px 12px; border-radius: 16px;
  cursor: pointer; transition: all 120ms;
}
.rp-toggle .btn-mini:hover {
  border-color: var(--accent-soft); background: white;
}
.rp-toggle .btn-mini.active {
  background: var(--accent); color: white; border-color: var(--accent);
}

/* Stage ------------------------------------------------------- */
.rp-stage {
  background: white;
  border: 1px solid var(--rule); border-radius: 6px;
  padding: 18px 16px 12px;
  overflow-x: auto;
}
.rp-row {
  display: flex; align-items: flex-end; gap: 18px;
  min-width: max-content;
}
.rp-axis {
  display: flex; flex-direction: column; justify-content: space-between;
  padding-right: 10px;
  border-right: 1px dashed var(--rule);
  font-family: var(--sans); font-size: 10px;
  text-transform: uppercase; letter-spacing: 0.08em;
  color: var(--ink-mute);
  white-space: nowrap;
  text-align: right;
  min-width: 90px;
}
.rp-axis-top { font-weight: 700; color: var(--accent); }
.rp-axis-bot { font-family: var(--mono); text-transform: none; letter-spacing: 0; }

.rp-column-wrap {
  display: flex; flex-direction: column; align-items: center; gap: 8px;
}
.rp-column {
  display: flex; flex-direction: column;
  border: 1px solid var(--rule);
  border-radius: 3px;
  overflow: hidden;
  background: var(--bg-elev);
}
.rp-cell { display: block; border-style: solid; border-width: 0.5px 0; }
.rp-cell-gap {
  display: flex; align-items: center; justify-content: center;
  font-family: var(--mono); font-size: 10px;
  color: var(--ink-mute); padding: 4px 0;
  background: #fbf6ee;
  border-top: 1px dashed var(--rule);
  border-bottom: 1px dashed var(--rule);
}
.rp-cell-gap-num { font-weight: 700; color: var(--ink); margin: 0 3px; }
.rp-token {
  font-family: var(--serif); font-size: 16px; font-weight: 600;
  color: var(--ink);
  padding: 4px 10px;
  background: var(--bg-elev);
  border-radius: 4px;
}

.rp-note {
  margin-top: 14px;
  padding: 8px 12px;
  font-family: var(--serif); font-size: 13px; font-style: italic;
  color: var(--ink-soft);
  background: var(--bg-elev);
  border-left: 3px solid var(--accent-soft);
  border-radius: 0 4px 4px 0;
}

/* ---- scorecard analogy · panels 1–3 ----------------------- */
.sc-panel { margin: 18px 0; }
.sc-head {
  display: flex; align-items: center; gap: 8px;
  font-family: var(--sans); font-size: 13px; font-weight: 700;
  color: var(--ink); margin-bottom: 10px;
}
.sc-step {
  flex: none; width: 20px; height: 20px; border-radius: 50%;
  background: var(--accent); color: #fff;
  font-family: var(--sans); font-size: 12px; font-weight: 700;
  display: inline-flex; align-items: center; justify-content: center;
}

/* word chips */
.sc-words { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 12px; }
.sc-chip {
  font-family: var(--serif); font-size: 15px;
  background: var(--bg-elev); border: 1px solid var(--rule);
  color: var(--ink-soft); padding: 4px 14px; border-radius: 16px;
  cursor: pointer; transition: all 120ms;
}
.sc-chip:hover { border-color: var(--accent-soft); background: #fff; }
.sc-chip.active { background: var(--accent); color: #fff; border-color: var(--accent); }

/* scorecard + readout */
.sc-body {
  display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 270px);
  gap: 14px; align-items: start;
}
@media (max-width: 720px) { .sc-body { grid-template-columns: 1fr; } }
.sc-card {
  background: #fff; border: 1px solid var(--rule); border-radius: 6px;
  padding: 8px 10px;
}
.sc-row {
  display: grid; grid-template-columns: 20px 14px 1fr 86px 44px;
  align-items: center; gap: 8px;
  padding: 3px 6px; border-radius: 4px;
  cursor: pointer; transition: background 100ms;
}
.sc-row:hover, .sc-row.active { background: var(--bg-viz); }
.sc-row.active { box-shadow: inset 0 0 0 1px var(--accent-soft); }
.sc-row-i { font-family: var(--mono); font-size: 10px; color: var(--ink-mute); text-align: right; }
.sc-dot { width: 13px; height: 13px; border-radius: 50%; border: 1px solid; }
.sc-row-name { font-family: var(--sans); font-size: 12.5px; color: var(--ink-soft); }
.sc-bar { position: relative; height: 8px; background: var(--bg-code); border-radius: 4px; }
.sc-bar-mid { position: absolute; left: 50%; top: -2px; bottom: -2px; width: 1px; background: var(--rule); }
.sc-bar-fill { position: absolute; top: 0; bottom: 0; border-radius: 4px; }
.sc-row-val { font-family: var(--mono); font-size: 11px; color: var(--ink-mute); text-align: right; }

.sc-readout {
  background: var(--bg-viz); border-left: 3px solid var(--accent);
  border-radius: 0 5px 5px 0; padding: 12px 14px; min-height: 90px;
  position: sticky; top: 12px;
}
.sc-readout-tag {
  font-family: var(--sans); font-size: 10px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.08em; color: var(--accent);
}
.sc-readout-text {
  font-family: var(--serif); font-size: 14px; line-height: 1.5;
  color: var(--ink-soft); margin-top: 6px;
}
.sc-readout-text strong { color: var(--ink); }
.sc-foot {
  font-family: var(--sans); font-size: 12px; line-height: 1.5;
  color: var(--ink-mute); margin: 10px 0 0;
}
.sc-foot strong { color: var(--ink-soft); }

/* width explorer */
.sc-width { display: flex; gap: 22px; align-items: stretch; }
@media (max-width: 720px) { .sc-width { flex-direction: column; align-items: center; } }
.sc-width-colwrap { display: flex; align-items: flex-end; flex: none; }
.sc-width-col {
  display: flex; flex-direction: column;
  border: 1px solid var(--rule); border-radius: 4px; overflow: hidden;
  background: var(--bg-elev);
}
.sc-wc-cell { display: block; width: 100%; border-bottom: 0.5px solid; }
.sc-width-ctl { flex: 1; display: flex; flex-direction: column; gap: 12px; min-width: 0; }
.sc-width-ctl input[type="range"] { width: 100%; accent-color: var(--accent); cursor: pointer; }
.sc-width-presets { display: flex; flex-wrap: wrap; gap: 6px; }
.sc-width-num {
  font-family: var(--serif); font-size: 32px; font-weight: 700;
  color: var(--accent); line-height: 1;
}
.sc-width-unit {
  font-family: var(--sans); font-size: 11px; text-transform: uppercase;
  letter-spacing: 0.06em; color: var(--ink-mute); margin-left: 8px;
}
.sc-width-name { font-family: var(--sans); font-size: 12px; font-weight: 700; color: var(--ink-soft); margin-top: 6px; }
.sc-width-cmp { font-family: var(--sans); font-size: 12px; color: var(--ink-mute); }
.sc-width-pool { display: flex; flex-wrap: wrap; gap: 5px; margin-top: 2px; }
.sc-pool-chip {
  font-family: var(--mono); font-size: 10.5px;
  background: var(--bg-code); border: 1px solid var(--rule);
  border-radius: 10px; padding: 2px 8px; color: var(--ink-soft);
}
.sc-pool-more { font-family: var(--sans); font-size: 11.5px; font-style: italic; color: var(--ink-mute); align-self: center; }

/* ============================================================
   §6.2 · microGPT → nanochat scaling widget (#viz-scale)
   ============================================================ */
.scale-stage {
  display: flex; gap: 32px; align-items: flex-end; justify-content: center;
  padding: 8px 0 0; flex-wrap: wrap;
}
.scale-col { display: flex; flex-direction: column; align-items: center; }
.scale-col-head {
  font-family: var(--sans); font-size: 12px; font-weight: 700;
  color: var(--ink); margin-bottom: 8px; text-align: center;
}
.scale-col-sub { display: block; font-weight: 400; font-size: 11px; color: var(--ink-mute); }
.scale-svg { height: 300px; width: auto; max-width: 100%; overflow: visible; }
.scale-svg text { font-family: var(--mono); font-size: 10px; fill: var(--ink-mute); }
.scale-block { fill: var(--accent-soft); stroke: var(--accent); stroke-width: 0.6; }
.scale-block-micro { fill: #e2ece6; stroke: #6f9d86; }
.scale-caliper { stroke: var(--ink-mute); stroke-width: 0.7; }

.scale-controls {
  display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
  justify-content: center; margin: 16px 0 2px;
}
.scale-controls label {
  font-family: var(--sans); font-size: 11px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.06em; color: var(--ink-mute);
}
.scale-controls input[type="range"] { width: 260px; max-width: 60vw; accent-color: var(--accent); }
.scale-controls output {
  font-family: var(--mono); font-weight: 700; font-size: 15px;
  color: var(--accent); min-width: 1.6em; text-align: center;
}
.scale-presets { display: flex; gap: 6px; flex-wrap: wrap; }

.scale-readout {
  display: grid; grid-template-columns: 1.5fr 1fr 1fr;
  margin-top: 14px; border: 1px solid var(--rule); border-radius: 6px; overflow: hidden;
  font-family: var(--mono); font-size: 13px;
}
.scale-readout > div { padding: 7px 12px; border-top: 1px solid var(--rule); }
.scale-readout > div.scale-rhead {
  border-top: none; background: #faf8f2;
  font-family: var(--sans); font-weight: 700; font-size: 11px;
  text-transform: uppercase; letter-spacing: 0.05em; color: var(--ink-mute);
}
.scale-readout > div.scale-rlabel { color: var(--ink-mute); }
.scale-readout > div.scale-rnano { color: var(--accent); font-weight: 700; }

/* Q / K / V attention-matrix sub-panel inside #viz-scale */
.scale-attn { margin-top: 18px; }
.scale-attn-head {
  font-family: var(--sans); font-size: 11px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.05em; color: var(--ink-mute);
  margin-bottom: 12px;
}
.scale-attn-row {
  display: flex; gap: 20px; align-items: flex-end;
  min-height: 150px; flex-wrap: wrap;
}
.scale-attn-item { display: flex; flex-direction: column; align-items: center; gap: 7px; }
.scale-mat {
  background-color: var(--accent-soft);
  background-image:
    linear-gradient(to right, rgba(177, 74, 46, 0.18) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(177, 74, 46, 0.18) 1px, transparent 1px);
  background-size: 8px 8px;
  border: 1px solid var(--accent); border-radius: 3px;
  transition: width 180ms ease, height 180ms ease;
}
.scale-mat-label {
  font-family: var(--mono); font-size: 13px; font-weight: 700; color: var(--accent);
}
.scale-attn-note {
  font-family: var(--mono); font-size: 12px; color: var(--ink-mute);
  line-height: 1.55; margin-top: 12px;
}

/* ============================================================
   §6.2 · pretraining-command anatomy (#viz-cmd)
   ============================================================ */
.cmd-line {
  display: flex; flex-wrap: wrap; gap: 8px; align-items: center;
  padding: 14px 16px; background: var(--bg-code);
  border: 1px solid var(--rule); border-radius: 6px;
  font-family: var(--mono); font-size: 14px;
}
.cmd-part {
  padding: 4px 8px; border-radius: 4px; cursor: pointer;
  color: var(--ink); background: rgba(177, 74, 46, 0.06);
  border: 1px solid transparent;
  border-bottom: 2px dotted var(--accent-soft);
  transition: background 140ms, border-color 140ms, color 140ms;
}
.cmd-part:hover, .cmd-part:focus, .cmd-part.active {
  background: var(--accent-soft); border-color: var(--accent);
  border-bottom-style: solid; color: var(--ink); outline: none;
}
.cmd-detail {
  margin-top: 12px; padding: 12px 16px;
  background: var(--bg-elev); border-left: 3px solid var(--accent);
  border-radius: 0 4px 4px 0;
  font-family: var(--serif); font-size: 15px; line-height: 1.55; color: var(--ink-soft);
  min-height: 3.5em;
}
.cmd-detail code { font-family: var(--mono); font-size: 0.85em; }

/* ============================================================ */
/* §8 · Inside nanochat/ — annotated source-code tour.           */
/* Same hover-per-line pattern as Lab 02's .annotated-code and   */
/* this lab's .annotated-term: each .code-step can carry         */
/* data-step-name + data-explain; hovering (or keyboard-         */
/* focusing) a line updates the .code-explain-panel below the    */
/* block. Lines sharing a data-step light up together.           */
/* ============================================================ */
.annotated-code-wrap { margin: 14px 0 24px 0; }

.code-file-head {
  display: flex; align-items: baseline; gap: 12px; flex-wrap: wrap;
  font-family: var(--mono); font-size: 12px; color: var(--ink-mute);
  background: var(--bg-elev); border: 1px solid var(--rule); border-bottom: none;
  border-radius: 6px 6px 0 0; padding: 8px 16px;
}
.code-file-head .code-file-name { font-weight: 700; color: var(--ink); font-size: 13px; }
.code-file-head .code-file-span { font-style: normal; }
.code-file-head a { margin-left: auto; font-family: var(--sans); font-size: 12px; }

.annotated-code {
  font-family: var(--mono); font-size: 13px; line-height: 1.6;
  background: var(--bg-code); border: 1px solid var(--rule);
  border-radius: 6px; padding: 12px 0; overflow-x: auto;
}
.code-file-head + .annotated-code { border-radius: 0 0 6px 6px; border-top: none; }

.annotated-code .code-step {
  display: block; white-space: pre; padding: 0 16px;
  border-left: 3px solid transparent;
  transition: background 0.08s, border-color 0.08s;
}
.annotated-code .code-step[data-explain] { cursor: pointer; }
.annotated-code .code-step[data-explain]:hover,
.annotated-code .code-step[data-explain]:focus,
.annotated-code .code-step.active {
  background: var(--highlight); border-left-color: var(--accent); outline: none;
}
.annotated-code .code-step.code-elide {
  color: var(--ink-mute); font-style: italic;
}

.code-explain-panel {
  margin-top: 10px; padding: 12px 16px; min-height: 68px;
  background: var(--bg-elev); border-left: 3px solid var(--accent);
  border-radius: 0 4px 4px 0;
}
.code-explain-tag {
  font-family: var(--mono); font-size: 12px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.06em;
  color: var(--ink-mute); margin-bottom: 6px;
}
.code-explain-text {
  font-family: var(--serif); font-size: 15px; line-height: 1.55; color: var(--ink);
}
.code-explain-text code {
  font-family: var(--mono); font-size: 13px;
  background: var(--bg-code); padding: 1px 5px; border-radius: 3px;
}

/* File-map table + per-file "what/why" summary cards used in §8 */
.src-file-tag {
  font-family: var(--mono); font-size: 0.85em; white-space: nowrap;
}
body.presentation-mode .annotated-code { font-size: 16px; }
body.presentation-mode .code-explain-text { font-size: 18px; }

/* "Read the source" strand — recurring inline code-tour headings.
   The rs-tag chip also appears inline in §2's map prose. */
h4.read-src {
  font-family: var(--serif); font-size: 20px; font-weight: 700;
  color: var(--ink); margin: 40px 0 10px 0;
}
h4.read-src code { font-size: 18px; }
.rs-tag {
  display: inline-block; padding: 2px 9px; margin-right: 10px;
  font-family: var(--mono); font-size: 11px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.08em;
  color: var(--accent); background: var(--bg-elev);
  border: 1px solid var(--accent-soft); border-radius: 10px;
  vertical-align: 3px;
}
body.presentation-mode h4.read-src { font-size: 26px; }

/* ============================================================ */
/* #viz-rope — rotary embeddings widget                          */
/* ============================================================ */
#viz-rope .btn-mini, #viz-flash .btn-mini {
  font-family: var(--mono); font-size: 12px;
  background: var(--bg-elev); border: 1px solid var(--rule);
  color: var(--ink-soft); padding: 6px 12px; border-radius: 16px;
  cursor: pointer; transition: all 120ms;
}
#viz-rope .btn-mini:hover, #viz-flash .btn-mini:hover {
  border-color: var(--accent-soft); background: white;
}
#viz-rope .btn-mini.active, #viz-flash .btn-mini.active {
  background: var(--accent); color: white; border-color: var(--accent);
}

.rope-panel {
  background: white; border: 1px solid var(--rule); border-radius: 6px;
  padding: 14px 16px; margin: 14px 0;
}
.rope-dials {
  display: flex; flex-wrap: wrap; gap: 10px; justify-content: center;
  margin: 6px 0 12px;
}
.rope-dial { text-align: center; }
.rope-dial svg { display: block; }
.rope-dial-label {
  font-family: var(--mono); font-size: 10.5px; color: var(--ink-mute);
  margin-top: 2px; line-height: 1.35;
}
.rope-ctl {
  display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
  font-family: var(--sans); font-size: 13px; color: var(--ink-soft);
  margin: 4px 0 10px;
}
.rope-ctl input[type="range"] { flex: 1 1 180px; max-width: 320px; }
.rope-ctl output { font-family: var(--mono); font-size: 13px; font-weight: 700; color: var(--ink); min-width: 2ch; }
.rope-note {
  font-family: var(--serif); font-size: 14.5px; line-height: 1.55;
  color: var(--ink-soft); margin: 8px 0 2px;
}
.rope-rel {
  display: grid; grid-template-columns: minmax(200px, 250px) minmax(0, 1fr);
  gap: 18px; align-items: center;
}
@media (max-width: 720px) { .rope-rel { grid-template-columns: 1fr; } }
#rope-rel-svg { width: 100%; height: auto; }
.rope-slider-row {
  display: flex; align-items: center; gap: 10px;
  font-family: var(--sans); font-size: 13px; color: var(--ink-soft);
  margin-bottom: 8px;
}
.rope-slider-row label { min-width: 130px; }
.rope-slider-row input[type="range"] { flex: 1; }
.rope-slider-row output { font-family: var(--mono); font-weight: 700; color: var(--ink); min-width: 2ch; }
.rope-btns { display: flex; gap: 8px; margin: 6px 0 12px; }
.rope-readout {
  font-family: var(--mono); font-size: 13px; line-height: 1.8;
  background: var(--bg-code); border-radius: 6px; padding: 10px 14px;
  color: var(--ink);
}
.rope-readout .rr-hold {
  display: inline-block; padding: 0 6px; border-radius: 3px;
  background: var(--highlight); font-weight: 700;
}
.rope-readout .rr-q { color: #b14a2e; font-weight: 700; }
.rope-readout .rr-k { color: #2e5fb1; font-weight: 700; }

/* ============================================================ */
/* #viz-flash — flash attention widget                           */
/* ============================================================ */
.flash-controls {
  display: flex; align-items: center; gap: 8px; flex-wrap: wrap;
  margin: 6px 0 14px;
}
.flash-ctl-label {
  font-family: var(--sans); font-size: 11px; text-transform: uppercase;
  letter-spacing: 0.08em; color: var(--ink-mute); margin-left: 6px;
}
.flash-ctl-label:first-child { margin-left: 0; }
.flash-stage {
  display: grid; grid-template-columns: minmax(0, 1fr) 220px;
  gap: 16px; align-items: start;
}
@media (max-width: 760px) { .flash-stage { grid-template-columns: 1fr; } }
.flash-left { background: white; border: 1px solid var(--rule); border-radius: 6px; padding: 12px; }
.flash-grid-title {
  font-family: var(--mono); font-size: 11.5px; color: var(--ink-mute);
  margin-bottom: 8px;
}
#flash-grid { width: 100%; height: auto; display: block; }
.flash-legend {
  display: flex; flex-wrap: wrap; gap: 12px; margin-top: 10px;
  font-family: var(--sans); font-size: 11.5px; color: var(--ink-soft);
}
.flash-legend .fl-swatch {
  display: inline-block; width: 11px; height: 11px; border-radius: 2px;
  border: 1px solid var(--rule); margin-right: 4px; vertical-align: -1px;
}
.flash-side { display: flex; flex-direction: column; gap: 12px; }
.flash-box {
  background: white; border: 1px solid var(--rule); border-radius: 6px;
  padding: 10px 12px;
}
.flash-side-title {
  font-family: var(--sans); font-size: 11px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.07em;
  color: var(--ink-mute); margin-bottom: 8px;
}
#flash-sram { width: 84px; height: 84px; display: block; margin: 0 auto; }
.flash-acc {
  font-family: var(--mono); font-size: 11px; line-height: 1.7;
  color: var(--ink-soft); margin-top: 8px; min-height: 3.2em;
}
.flash-acc .fa-chip {
  display: inline-block; background: var(--bg-code); border-radius: 3px;
  padding: 0 5px; margin: 0 3px 3px 0;
}
.flash-acc .fa-chip.pulse { background: var(--highlight); color: var(--ink); font-weight: 700; }
.flash-meter {
  height: 14px; background: var(--bg-code); border: 1px solid var(--rule);
  border-radius: 7px; overflow: hidden;
}
.flash-meter-fill {
  height: 100%; width: 0%; background: #b14a2e; border-radius: 7px;
  transition: width 80ms linear;
}
.flash-meter-label {
  font-family: var(--mono); font-size: 11px; color: var(--ink-soft); margin-top: 6px;
}
.flash-status {
  font-family: var(--serif); font-size: 13.5px; line-height: 1.5;
  color: var(--ink); background: var(--bg-elev);
  border-left: 3px solid var(--accent); border-radius: 0 4px 4px 0;
  padding: 8px 12px; min-height: 4.2em;
}