.bt-learn {
  --learn-bg: #0b131e;
  --learn-panel: #111b28;
  --learn-panel-2: #0d1723;
  --learn-line: rgba(167, 194, 223, .18);
  --learn-ink: #f5f7fa;
  --learn-muted: #aab9ca;
  --learn-soft: #8091a6;
  --learn-accent: #ff9d37;
  --learn-chart: #09121d;
  color: var(--learn-ink);
}
html[data-theme="light"] .bt-learn {
  --learn-bg: #f1f5f9;
  --learn-panel: #ffffff;
  --learn-panel-2: #f7f9fc;
  --learn-line: rgba(48, 74, 101, .18);
  --learn-ink: #19283b;
  --learn-muted: #506277;
  --learn-soft: #6d7f94;
  --learn-accent: #b96107;
  --learn-chart: #f7f9fc;
}
.bt-learn * { box-sizing: border-box; }
.bt-learn [hidden] { display: none !important; }
.bt-lab { overflow-anchor: none; }
.bt-app-main:has(> .bt-lab) { padding-top: 26px; }
.bt-app-page-heading:has(~ .bt-lab) { margin-bottom: 12px; }
.bt-app-page-heading:has(~ .bt-lab) h1 { font-size: clamp(24px,2.2vw,32px); }
.bt-lab__overview { display: flex; align-items: center; gap: 16px; margin-bottom: 20px; color: var(--learn-muted); font-size: 12px; }
.bt-lab__back, .bt-lab__history { color: var(--learn-muted); text-decoration: none; padding-block: 12px; }
.bt-lab__history { margin-left: auto; }
.bt-lab__overall { display: flex; align-items: center; flex-wrap: wrap; gap: 8px 14px; }
.bt-lab__overall > span { color: var(--learn-ink); font-weight: 650; }
.bt-lab__overall progress { width: 130px; height: 4px; border: 0; border-radius: 8px; background: var(--learn-line); accent-color: var(--learn-accent); overflow: hidden; }
.bt-lab__overall progress::-webkit-progress-bar { background: var(--learn-line); }
.bt-lab__overall progress::-webkit-progress-value { background: var(--learn-accent); }
.bt-lab__navigation { margin-bottom: 18px; padding: 16px; border: 1px solid var(--learn-line); border-radius: 14px; background: var(--learn-panel); }
.bt-lab__selector-bar { display: flex; align-items: center; gap: 16px; }
.bt-lab__selector-bar .bt-lab__levels { flex: 1; min-width: 0; }
.bt-lab__levels { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); gap: 6px; }
.bt-lab__level { display: grid; gap: 7px; min-width: 0; min-height: 44px; padding: 12px 14px; border: 1px solid var(--learn-line); border-radius: 8px; background: var(--learn-panel-2); color: var(--learn-muted); text-align: left; font: inherit; cursor: pointer; }
.bt-lab__level[aria-pressed="true"] { border-color: var(--learn-accent); background: color-mix(in srgb,var(--learn-accent) 8%,var(--learn-panel)); }
.bt-lab__level strong { color: var(--learn-ink); font-size: 13px; }
.bt-lab__level-heading { display: flex; align-items: center; justify-content: space-between; gap: 8px; }
.bt-lab__level-count { color: var(--learn-muted); font-size: 11px; white-space: nowrap; }
.bt-lab__level-goal { color: var(--learn-muted); font-size: 11px; line-height: 1.4; }
.bt-lab__level-short { display: none; color: var(--learn-muted); font-size: 10px; line-height: 1.4; }
.bt-lab__level-progress { height: 3px; margin-top: 2px; border-radius: 4px; background: var(--learn-line); overflow: hidden; }
.bt-lab__level-progress > span { display: block; width: 0; height: 100%; background: var(--learn-accent); }
.bt-lab__level[aria-pressed="true"] strong { color: var(--learn-accent); }
.bt-lab__level:disabled { cursor: default; opacity: .65; }
.bt-lab__navigation button:focus-visible, .bt-lab__practice-progress summary:focus-visible, .bt-lab__overview a:focus-visible { outline: 2px solid var(--learn-accent); outline-offset: 3px; }
.bt-lab__cases-toggle { display: flex; align-items: center; justify-content: center; gap: 8px; flex-shrink: 0; min-height: 44px; padding: 8px 10px; border: 0; border-radius: 7px; color: var(--learn-muted); background: transparent; font: inherit; font-size: 12px; cursor: pointer; }
.bt-lab__cases-toggle:hover { background: var(--learn-panel-2); color: var(--learn-ink); }
.bt-lab__cases-toggle:disabled { opacity: .6; cursor: default; }
.bt-lab__cases-head { display: flex; align-items: center; flex-wrap: wrap; justify-content: space-between; gap: 8px 20px; margin: 16px 0 10px; }
.bt-lab__level-hint, .bt-lab__access-note { margin: 0; color: var(--learn-muted); font-size: 11px; line-height: 1.5; }
.bt-lab__level-hint { max-width: 48%; }
.bt-lab__filters { display: flex; flex-wrap: wrap; gap: 4px; }
.bt-lab__filters button { min-height: 44px; padding: 8px 10px; border: 1px solid transparent; border-radius: 7px; background: transparent; color: var(--learn-muted); font: inherit; font-size: 12px; cursor: pointer; }
.bt-lab__filters button > span { margin-left: 5px; color: var(--learn-soft); font-size: 11px; }
.bt-lab__filters button[aria-pressed="true"] { color: var(--learn-ink); background: var(--learn-panel-2); border-color: var(--learn-line); }
.bt-lab__cases-grid { display: grid; grid-template-columns: repeat(5,minmax(0,1fr)); gap: 8px; }
.bt-lab__case-card { display: flex; flex-direction: column; justify-content: space-between; gap: 10px; min-width: 0; padding: 13px 14px; border: 1px solid var(--learn-line); border-radius: 9px; background: var(--learn-panel-2); color: var(--learn-ink); text-align: left; font: inherit; cursor: pointer; }
.bt-lab__case-card:hover { border-color: var(--learn-muted); }
.bt-lab__case-card[aria-current="true"] { border-color: var(--learn-accent); background: color-mix(in srgb,var(--learn-accent) 7%,var(--learn-panel-2)); }
.bt-lab__case-card > strong { font-size: 12px; line-height: 1.5; font-weight: 600; overflow-wrap: anywhere; }
.bt-lab__case-card:disabled { cursor: default; }
.bt-lab__case-card[data-available="false"] > strong { color: var(--learn-soft); }
.bt-lab__card-meta { display: flex; align-items: center; flex-wrap: wrap; justify-content: space-between; gap: 5px; }
.bt-lab__status { display: inline-flex; align-items: center; gap: 6px; min-width: 0; max-width: 100%; font-size: 10px; line-height: 1.4; color: var(--learn-muted); }
.bt-lab__status > span { min-width: 0; }
.bt-lab__status-icon { width: 14px; height: 14px; flex: 0 0 14px; fill: none; stroke: currentColor; stroke-width: 1.5; stroke-linecap: round; stroke-linejoin: round; }
.bt-lab__status[data-status="in-progress"], .bt-lab__current-progress[data-status="in-progress"] { color: var(--learn-accent); }
.bt-lab__status[data-status="awaiting-review"], .bt-lab__current-progress[data-status="awaiting-review"] { color: #92bff2; }
.bt-lab__status[data-status="completed"], .bt-lab__current-progress[data-status="completed"] { color: #78c6a1; }
html[data-theme="light"] .bt-lab__status[data-status="awaiting-review"], html[data-theme="light"] .bt-lab__current-progress[data-status="awaiting-review"] { color: #315f97; }
html[data-theme="light"] .bt-lab__status[data-status="completed"], html[data-theme="light"] .bt-lab__current-progress[data-status="completed"] { color: #277150; }
.bt-lab__card-access { color: var(--learn-soft); font-size: 10px; }
.bt-lab__cases-empty { grid-column: 1/-1; margin: 0; padding: 22px 8px; color: var(--learn-muted); font-size: 12px; line-height: 1.6; }
.bt-lab__cases-empty a { color: var(--learn-accent); }
.bt-lab__access-note { margin-top: 14px; }
.bt-lab__access-note a { color: var(--learn-accent); text-underline-offset: 3px; }
.bt-lab__navigation[data-collapsed="true"] { padding: 4px 10px; }
.bt-lab__navigation[data-collapsed="true"] .bt-lab__level { padding: 8px 12px; background: transparent; }
.bt-lab__navigation[data-collapsed="true"] .bt-lab__level-goal, .bt-lab__navigation[data-collapsed="true"] .bt-lab__level-short, .bt-lab__navigation[data-collapsed="true"] .bt-lab__level-progress { display: none; }
.bt-lab__current-progress { color: var(--learn-muted); font-size: 11px; }
.bt-lab__save-state { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin-bottom: 8px; color: var(--learn-soft); font-size: 11px; line-height: 1.5; }
.bt-lab__save-state:has(> span:empty) { display: none; }
.bt-lab__save-state button { min-height: 44px; padding: 8px 12px; border: 1px solid var(--learn-line); border-radius: 7px; background: var(--learn-panel-2); color: var(--learn-ink); font: inherit; cursor: pointer; }
.bt-lab__review-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; }
.bt-lab__retry { margin-bottom: 16px; }
.bt-lab__case-level { color: var(--learn-accent); font-size: 11px; font-weight: 700; }
.bt-lab__phases { display: flex; flex-wrap: wrap; gap: 8px 18px; padding: 0; margin: 16px 0; list-style: none; color: var(--learn-soft); font-size: 11px; }
.bt-lab__phases li { display: flex; align-items: center; gap: 6px; }
.bt-lab__phase-number { display: grid; place-items: center; width: 23px; height: 23px; border: 1px solid var(--learn-line); border-radius: 50%; }
.bt-lab__phases li[data-status="active"] { color: var(--learn-ink); font-weight: 750; }
.bt-lab__phases li[data-status="active"] .bt-lab__phase-number { background: var(--learn-accent); color: var(--learn-bg); border-color: var(--learn-accent); }
.bt-lab__phases li[data-status="done"] .bt-lab__phase-number { color: var(--learn-accent); }
.bt-lab__workspace[data-state="loading"] .bt-lab__chart-shell, .bt-lab__workspace[data-state="error"] .bt-lab__chart-shell { opacity: .55; pointer-events: none; }
.bt-lab__workspace[data-state="loading"] .bt-lab__decision, .bt-lab__workspace[data-state="error"] .bt-lab__decision { pointer-events: none; }
.bt-lab__practice-progress { padding: 12px 20px; border: 1px solid var(--learn-line); border-radius: 12px; background: var(--learn-panel); }
.bt-lab__practice-progress > summary { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 16px; min-height: 44px; color: var(--learn-ink); font-size: 12px; cursor: pointer; list-style: none; }
.bt-lab__practice-progress > summary span { color: var(--learn-soft); font-size: 11px; }
.bt-lab__practice-progress > summary::after { content: "+"; margin-left: auto; color: var(--learn-soft); font-size: 18px; }
.bt-lab__practice-progress[open] > summary::after { content: "−"; }
.bt-lab__practice-progress > summary::-webkit-details-marker { display: none; }
.bt-lab__practice-progress-content { display: grid; gap: 18px; padding: 16px 0 6px; border-top: 1px solid var(--learn-line); }
.bt-lab__practice-progress-content > a { color: var(--learn-accent); font-size: 12px; text-underline-offset: 3px; }
.bt-lab__follow-state { color: var(--learn-muted); font-size: 11px; }
.bt-lab__indicators { display: flex; align-items: center; flex-wrap: wrap; gap: 7px 12px; padding-bottom: 12px; color: var(--learn-muted); font-size: 11px; }
.bt-lab__indicators button { min-height: 44px; padding: 7px 12px; border: 1px solid var(--learn-line); border-radius: 7px; background: var(--learn-panel-2); color: var(--learn-muted); cursor: pointer; font: inherit; }
.bt-lab__indicators button[aria-pressed="true"] { color: var(--learn-accent); border-color: var(--learn-accent); }
.bt-lab__context { min-width: 0; margin-bottom: 10px; border: 1px solid var(--learn-line); border-radius: 10px; background: var(--learn-panel-2); }
.bt-lab__context summary { display: flex; align-items: center; gap: 8px; min-height: 44px; padding: 8px 12px; color: var(--learn-ink); font-size: 12px; font-weight: 750; cursor: pointer; }
.bt-lab__context summary::after { content: "+"; margin-left: auto; color: var(--learn-muted); font-size: 18px; }
.bt-lab__context[open] summary::after { content: "−"; }
.bt-lab__context p { margin: 10px 12px; font-size: 11px; line-height: 1.6; color: var(--learn-muted); overflow-wrap: anywhere; }
.bt-lab__context-chart { position: relative; width: calc(100% - 24px); height: 225px; margin: 0 12px; overflow: hidden; border-radius: 7px; }
.bt-lab__reflection { display: grid; gap: 12px; }
.bt-lab__evidence, .bt-lab__condition { display: grid; min-width: 0; gap: 10px; margin: 0; padding: 14px; border: 1px solid var(--learn-line); border-radius: 10px; background: var(--learn-panel); }
.bt-lab__evidence legend, .bt-lab__condition legend { padding: 0 5px; font-size: 12px; font-weight: 800; }
.bt-lab__evidence legend span { color: var(--learn-muted); font-size: 10px; font-weight: 500; }
.bt-lab__evidence .bt-lab__field, .bt-lab__condition .bt-lab__field { margin: 0; }
.bt-lab__evidence-facts { margin: 0; color: var(--learn-muted); font-size: 11px; line-height: 1.6; overflow-wrap: anywhere; }
.bt-lab__evidence select, .bt-lab__condition select { min-width: 0; max-width: 100%; }
.bt-lab__evidence button { min-height: 44px; white-space: normal; }
.bt-lab__evidence button[aria-pressed="true"] { border-color: var(--learn-accent); }
.bt-lab__evidence button:focus-visible { outline: 2px solid var(--learn-accent); outline-offset: 3px; }
.bt-lab__field textarea { width: 100%; padding: 10px; border: 1px solid var(--learn-line); border-radius: 8px; background: var(--learn-panel); color: var(--learn-ink); font: inherit; font-size: 12px; line-height: 1.6; resize: vertical; }
.bt-lab__review-result { display: grid; gap: 16px; }
.bt-lab__review-result h3 { margin: 0; font-size: 18px; }
.bt-lab__comparison { display: flex; flex-wrap: wrap; align-items: center; gap: 14px 20px; margin-bottom: 14px; padding: 14px; border: 1px solid var(--learn-line); border-radius: 10px; background: var(--learn-panel-2); }
.bt-lab__comparison h3 { margin: 0; font-size: 15px; }
.bt-lab__comparison-layers { display: flex; flex-wrap: wrap; gap: 8px 16px; min-width: 0; margin: 0; padding: 0; border: 0; }
.bt-lab__comparison-layers legend { font-size: 11px; color: var(--learn-muted); }
.bt-lab__comparison-layers label { display: flex; align-items: center; gap: 7px; min-height: 44px; font-size: 12px; cursor: pointer; }
.bt-lab__comparison-layers input { width: 18px; height: 18px; margin: 0; accent-color: var(--learn-accent); }
.bt-lab__layer-line { width: 20px; border-top: 2px solid var(--learn-muted); }
.bt-lab__layer-line--author { border-top-style: dashed; border-color: var(--learn-accent); }
.bt-lab__comparison-views { display: flex; flex-wrap: wrap; gap: 8px; }
.bt-lab__comparison-views button { min-height: 44px; padding: 8px 12px; border: 1px solid var(--learn-line); border-radius: 7px; background: var(--learn-panel); color: var(--learn-muted); font: inherit; font-size: 12px; cursor: pointer; }
.bt-lab__comparison-views button[aria-pressed="true"] { border-color: var(--learn-accent); color: var(--learn-accent); }
.bt-lab__comparison input:focus-visible, .bt-lab__comparison button:focus-visible, .bt-lab__author-review summary:focus-visible { outline: 2px solid var(--learn-accent); outline-offset: 3px; }
.bt-lab__author-review { display: grid; gap: 14px; margin-top: 18px; font-size: 12px; line-height: 1.7; }
.bt-lab__author-review p { margin: 0; overflow-wrap: anywhere; }
.bt-lab__author-areas { display: grid; grid-template-columns: repeat(auto-fit,minmax(min(100%,240px),1fr)); gap: 12px; }
.bt-lab__author-area { min-width: 0; padding: 14px; border: 1px solid var(--learn-line); border-radius: 10px; background: var(--learn-panel-2); }
.bt-lab__author-area h4 { margin: 0 0 6px; font-size: 13px; }
.bt-lab__author-price { color: var(--learn-accent); margin-bottom: 8px; }
.bt-lab__author-review summary { display: flex; align-items: center; min-height: 44px; cursor: pointer; color: var(--learn-muted); }
.bt-lab__author-question { border-left: 2px solid var(--learn-accent); padding: 10px 14px; background: var(--learn-panel); }
.bt-lab__coach-summary { color: var(--learn-ink); font-size: 12px; line-height: 1.7; }
.bt-lab__coach-summary p { margin: 0 0 10px; }
.bt-lab__level:focus-visible, .bt-lab__indicators button:focus-visible, .bt-lab__context summary:focus-visible, .bt-lab__field textarea:focus-visible { outline: 2px solid var(--learn-accent); outline-offset: 3px; }
.bt-lab__sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }
.bt-learn a { color: inherit; }
.bt-learn__eyebrow { display: block; margin-bottom: 7px; color: var(--learn-accent); font-size: 11px; font-weight: 850; letter-spacing: .13em; text-transform: uppercase; }
.bt-learn__muted { margin: 0; color: var(--learn-muted); }
.bt-learn__subnav { display: flex; flex-wrap: wrap; gap: 8px 20px; margin-bottom: 20px; color: var(--learn-muted); font-size: 13px; font-weight: 700; }
.bt-learn__subnav a { text-decoration: none; }
.bt-learn__subnav a:hover, .bt-learn__subnav a:focus-visible { color: var(--learn-accent); }
.bt-learn__primary, .bt-learn__secondary { min-height: 46px; display: inline-flex; justify-content: center; align-items: center; border-radius: 10px; padding: 11px 18px; font: inherit; font-size: 14px; font-weight: 800; text-align: center; text-decoration: none; cursor: pointer; }
.bt-learn__primary { border: 1px solid #ffad50; color: #17100a !important; background: linear-gradient(180deg,#ffad49,#ff8a1f); }
.bt-learn__primary:hover { filter: brightness(1.06); }
.bt-learn__primary:disabled { cursor: wait; opacity: .65; }
.bt-learn__secondary { border: 1px solid var(--learn-line); color: var(--learn-ink); background: var(--learn-panel-2); }
.bt-learn__secondary:hover { border-color: var(--learn-accent); }
.bt-learn__primary:focus-visible, .bt-learn__secondary:focus-visible, .bt-lab__case-row:focus-visible, .bt-lab__select-label select:focus-visible { outline: 3px solid rgba(255,154,49,.4); outline-offset: 2px; }
.bt-learn__panel { border: 1px solid var(--learn-line); border-radius: 16px; padding: clamp(18px,2vw,26px); background: var(--learn-panel); }
.bt-learn__section-heading { display: flex; align-items: baseline; justify-content: space-between; flex-wrap: wrap; gap: 8px 24px; margin-bottom: 17px; }
.bt-learn__section-heading h2 { margin: 0; font-size: clamp(18px,1.5vw,22px); line-height: 1.2; letter-spacing: -.02em; }
.bt-learn__section-heading span { color: var(--learn-muted); font-size: 12px; }
.bt-learn__section-heading a { color: var(--learn-accent); font-size: 12px; font-weight: 800; text-decoration: underline; text-underline-offset: 3px; }

.bt-lab__notice { min-height: 44px; display: flex; align-items: center; margin-bottom: 15px; padding: 9px 15px; border: 1px solid var(--learn-line); border-radius: 10px; background: var(--learn-panel); color: var(--learn-muted); font-size: 13px; }
.bt-lab__notice[data-tone="error"] { border-color: rgba(223,79,89,.55); color: #f27d82; }
html[data-theme="light"] .bt-lab__notice[data-tone="error"] { color: #ac2738; }
.bt-lab__workspace { display: grid; grid-template-columns: minmax(0,1fr); border: 1px solid var(--learn-line); border-radius: 18px; overflow: hidden; overflow-anchor: none; scroll-margin-top: 80px; background: var(--learn-panel); box-shadow: 0 20px 50px rgba(0,0,0,.12); }
.bt-lab__main { display: flex; flex-direction: column; min-width: 0; padding: clamp(14px,1.5vw,22px); }
.bt-lab__casebar { display: block; }
.bt-lab__case-heading { min-width: 0; }
.bt-lab__casebar h2 { margin: 0; font-size: clamp(20px,2vw,28px); letter-spacing: -.03em; line-height: 1.15; }
.bt-lab__select-label { display: grid; gap: 5px; min-width: 190px; color: var(--learn-muted); font-size: 11px; font-weight: 800; }
.bt-lab__select-label select { width: 100%; min-height: 44px; padding: 8px 10px; border: 1px solid var(--learn-line); border-radius: 8px; background: var(--learn-panel-2); color: var(--learn-ink); font: inherit; font-size: 12px; }
.bt-lab__metadata { display: flex; flex-wrap: wrap; gap: 7px 17px; margin: 12px 0; color: var(--learn-muted); font-size: 12px; }
.bt-lab__metadata span + span { padding-left: 17px; border-left: 1px solid var(--learn-line); }
.bt-lab__chart-shell { position: relative; flex: 0 0 auto; height: clamp(320px,50svh,640px); min-height: 0; overflow: hidden; overflow-anchor: none; border: 1px solid var(--learn-line); border-radius: 11px; background: var(--learn-chart); }
.bt-lab__chart { position: relative; width: 100%; height: 100%; min-height: 0; }
.bt-lab__chart-empty { position: absolute; inset: 0; display: grid; place-items: center; padding: 20px; color: var(--learn-muted); text-align: center; }
.bt-learning-chart__annotations { position: absolute; inset: 0; z-index: 1; width: 100%; height: 100%; pointer-events: none; overflow: hidden; }
.bt-lab__chart.is-drawing { cursor: crosshair; }
.bt-lab__chart.is-drawing, .bt-lab__chart.is-editable [data-annotation-hit] { touch-action: none; }
.bt-lab__chart:focus-visible { outline: 2px solid var(--learn-accent); outline-offset: -3px; }
.bt-lab__case-status { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 12px; margin-bottom: 7px; }
.bt-lab__case-status .bt-learn__eyebrow { margin: 0; }
.bt-lab__stage { font-size: 10px; font-weight: 750; color: var(--learn-muted); }
.bt-lab__stage[data-state="playing"]::before { content: ""; display: inline-block; width: 7px; height: 7px; margin-right: 7px; border-radius: 50%; background: #29c9bd; }
.bt-lab__lesson-instruction { margin: 0 0 10px; color: var(--learn-ink); font-size: 12px; line-height: 1.45; }
.bt-lab__transport button[aria-pressed="true"] { border-color: var(--learn-accent); color: var(--learn-accent); }
.bt-lab__spotlight { position: absolute; inset: 0; z-index: 2; width: 100%; height: 100%; overflow: hidden; border-radius: 9px; pointer-events: none; }
.bt-lab__spotlight-shade { fill: rgba(3,9,17,.68); }
.bt-lab__spotlight-ring { fill: transparent; stroke: var(--learn-accent); stroke-width: 1.5; filter: drop-shadow(0 0 5px rgba(255,157,55,.2)); }
.bt-lab__coach-arrow { fill: none; stroke: var(--learn-accent); stroke-width: 2; stroke-linecap: round; }
.bt-lab__arrow-tip, .bt-lab__coach-anchor { fill: var(--learn-accent); }
.bt-lab__coach-anchor { stroke: #ffffff; stroke-width: 1.5; }
.bt-lab__spotlight[data-mode="drawing"] .bt-lab__spotlight-shade { opacity: .3; }
.bt-lab__coach { position: absolute; z-index: 3; top: 50%; left: 12px; transform: translateY(-50%); box-sizing: border-box; width: min(360px,calc(100% - 24px)); max-height: calc(100% - 24px); overflow-y: auto; overscroll-behavior: contain; scrollbar-width: thin; margin: 0; padding: 10px 18px 12px; border: 1px solid color-mix(in srgb,var(--learn-accent) 42%,var(--learn-line)); border-radius: 14px; background: var(--learn-panel-2); color: var(--learn-ink); box-shadow: 0 16px 48px rgba(0,0,0,.4), inset 0 1px rgba(255,255,255,.035); }
.bt-lab__coach-step { display: block; margin: 12px 0 8px; color: var(--learn-accent); font-size: 11px; font-weight: 650; }
.bt-lab__coach[data-mode="drawing"] { width: min(400px,calc(100% - 24px)); min-height: 46px; padding: 8px 12px 8px 48px; pointer-events: none; }
.bt-lab__coach[data-mode="drawing"] .bt-lab__coach-message, .bt-lab__coach[data-mode="drawing"] .bt-lab__coach-step { display: none; }
.bt-lab__coach-head { display: flex; align-items: center; justify-content: space-between; gap: 8px; margin-bottom: 10px; padding-bottom: 7px; border-bottom: 1px solid var(--learn-line); }
.bt-lab__coach-head button { flex: 0 0 44px; width: 44px; height: 44px; border: 0; border-radius: 6px; background: transparent; color: var(--learn-muted); font-size: 22px; cursor: pointer; }
.bt-lab__coach-head button:not(.bt-lab__coach-move) { font-size: 22px; }
.bt-lab__coach-head button:hover { background: var(--learn-panel); color: var(--learn-ink); }
.bt-lab__coach-head .bt-lab__coach-move { display: flex; align-items: center; gap: 8px; flex: 1 1 auto; width: auto; min-width: 0; min-height: 44px; height: auto; padding: 5px 2px; cursor: grab; touch-action: none; user-select: none; text-align: left; font: inherit; pointer-events: auto; }
.bt-lab__coach-move svg { flex: 0 0 16px; color: var(--learn-accent); }
.bt-lab__coach-title { display: grid; gap: 3px; min-width: 0; }
.bt-lab__coach-title small { color: var(--learn-soft); font-size: 11px; font-weight: 400; line-height: 1.3; }
.bt-lab__coach-move .bt-lab__coach-name { margin: 0; }
.bt-lab__coach[data-moving="true"] { border-color: var(--learn-accent); }
.bt-lab__coach[data-moving="true"] .bt-lab__coach-move { cursor: grabbing; }
.bt-lab__coach-head button:focus-visible { outline: 2px solid var(--learn-accent); outline-offset: 2px; }
.bt-lab__coach[data-mode="drawing"] .bt-lab__coach-head { position: absolute; left: 0; top: 0; bottom: 0; width: 44px; margin: 0; padding: 0; border: 0; }
.bt-lab__coach[data-mode="drawing"] .bt-lab__coach-move { justify-content: center; width: 44px; height: 100%; padding: 0; }
.bt-lab__coach[data-mode="drawing"] .bt-lab__coach-title, .bt-lab__coach[data-mode="drawing"] [data-lab-coach-close], .bt-lab__coach[data-mode="drawing"] [data-lab-coach-reset], .bt-lab__coach[data-mode="drawing"] .bt-lab__coach-footer { display: none; }
.bt-lab__coach-name { display: block; color: var(--learn-ink); font-size: 13px; font-weight: 650; line-height: 1.35; }
.bt-lab__coach p { display: block; margin: 8px 0 14px; font-size: 14px; font-weight: 400; line-height: 1.6; overflow-wrap: anywhere; }
.bt-lab__coach .bt-lab__coach-focus { display: flex; align-items: center; gap: 7px; margin: 8px 0 10px; color: var(--learn-muted); font-size: 11px; line-height: 1.4; }
.bt-lab__coach-focus::before { content: ""; width: 10px; height: 10px; flex: 0 0 10px; border: 1px solid var(--learn-accent); border-radius: 3px; }
.bt-lab__coach-footer { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 0 12px; margin-top: 8px; border-top: 1px solid var(--learn-line); }
.bt-lab__coach-footer .bt-lab__coach-detail { min-height: 44px; margin: 0; font-size: 11px; }
.bt-lab__coach .bt-lab__coach-action { min-height: 44px; padding: 7px 12px; border: 1px solid #ffb158; border-radius: 7px; background: rgba(255,157,55,.1); color: #ffbd78; font: inherit; font-size: 12px; font-weight: 750; cursor: pointer; }
html[data-theme="light"] .bt-lab__coach { border-color: rgba(185,97,7,.35); background: rgba(255,255,255,.94); box-shadow: 0 12px 32px rgba(35,57,81,.14); color: #19283b; }
html[data-theme="light"] .bt-lab__coach-name { color: #a85200; }
html[data-theme="light"] .bt-lab__coach-action { border-color: #bb690f; color: #874604; }
html[data-theme="light"] .bt-lab__spotlight-shade { fill: rgba(27,42,61,.53); }
html[data-theme="light"] .bt-lab__spotlight-ring, html[data-theme="light"] .bt-lab__coach-arrow { stroke: #a95505; }
html[data-theme="light"] .bt-lab__arrow-tip, html[data-theme="light"] .bt-lab__coach-anchor { fill: #a95505; }
.bt-lab__transport { display: flex; flex-wrap: wrap; align-items: center; gap: 9px 17px; margin-bottom: 10px; padding: 8px 10px; border: 1px solid var(--learn-line); border-radius: 10px; background: var(--learn-panel-2); }
.bt-lab__transport-actions { display: flex; flex-wrap: wrap; gap: 7px; }
.bt-lab__transport button, .bt-lab__speed select { min-height: 44px; border: 1px solid var(--learn-line); border-radius: 8px; padding: 7px 12px; background: var(--learn-panel); color: var(--learn-ink); font: inherit; font-size: 12px; font-weight: 800; cursor: pointer; }
.bt-lab__transport button:hover, .bt-lab__speed select:hover { border-color: var(--learn-accent); }
.bt-lab__transport button:disabled { opacity: .55; cursor: default; }
.bt-lab__transport .bt-lab__transport-primary { min-width: 132px; border-color: var(--learn-accent); color: var(--learn-accent); }
.bt-lab__transport button:focus-visible, .bt-lab__speed select:focus-visible, .bt-lab__field input:focus-visible, .bt-lab__field textarea:focus-visible { outline: 3px solid rgba(255,154,49,.4); outline-offset: 2px; }
.bt-lab__speed { display: flex; align-items: center; gap: 7px; color: var(--learn-muted); font-size: 11px; font-weight: 750; }
.bt-lab__speed select { min-width: 65px; }
.bt-lab__progress { margin-left: auto; color: var(--learn-muted); font-size: 11px; font-variant-numeric: tabular-nums; }
.bt-lab__drawing-tools { display: flex; align-items: center; flex-wrap: wrap; gap: 5px; }
.bt-lab__drawing-tools button { min-height: 44px; padding: 7px 11px; border: 1px solid var(--learn-line); border-radius: 7px; background: var(--learn-panel-2); color: var(--learn-muted); font: inherit; font-size: 12px; font-weight: 700; cursor: pointer; }
.bt-lab__drawing-tools button[aria-pressed="true"] { border-color: var(--learn-accent); color: var(--learn-accent); background: rgba(255,157,55,.09); }
.bt-lab__drawing-tools button:disabled { opacity: .45; cursor: default; }
.bt-lab__tool-hint { min-height: 0; flex-shrink: 0; margin: 7px 0 11px; color: var(--learn-muted); font-size: 11px; line-height: 16px; }
.bt-lab__chart-foot { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 6px 15px; margin-top: 9px; color: var(--learn-soft); font-size: 11px; }
.bt-lab__task { display: flex; gap: 15px; align-items: baseline; margin-bottom: 13px; padding: 13px 15px; border-left: 2px solid var(--learn-accent); background: var(--learn-panel-2); }
.bt-lab__task strong { color: var(--learn-accent); font-size: 12px; }
.bt-lab__task p { margin: 0; color: var(--learn-ink); font-size: 13px; }
.bt-lab__decision { min-width: 0; border-top: 1px solid var(--learn-line); padding: clamp(14px,1.5vw,22px); background: var(--learn-panel-2); }
.bt-lab__decision form { display: grid; gap: 16px; }
.bt-lab__decision fieldset { min-width: 0; }
.bt-lab__checklist { display: grid; gap: 4px; }
.bt-lab__checklist button { min-height: 44px; display: flex; gap: 8px; align-items: center; padding: 6px 0; border: 0; background: transparent; color: var(--learn-muted); text-align: left; font: inherit; font-size: 12px; cursor: pointer; }
.bt-lab__checklist span { color: var(--learn-accent); font-size: 16px; }
.bt-lab__checklist .bt-lab__check-copy { display: grid; gap: 3px; color: var(--learn-ink); font-size: 12px; }
.bt-lab__check-copy small { color: var(--learn-muted); font-size: 11px; font-weight: 500; line-height: 1.4; }
.bt-lab__marks { min-height: 48px; max-height: 130px; overflow-y: auto; border-top: 1px solid var(--learn-line); border-bottom: 1px solid var(--learn-line); padding: 5px 0; }
.bt-lab__marks p { margin: 10px 0; color: var(--learn-soft); font-size: 11px; }
.bt-lab__mark { display: grid; grid-template-columns: minmax(0,1fr) 44px; align-items: center; gap: 4px; }
.bt-lab__mark.has-role { grid-template-columns: minmax(0,1fr) minmax(90px,130px) 44px; }
.bt-lab__mark-role { box-sizing: border-box; width: 100%; min-width: 0; min-height: 44px; padding: 5px; border: 1px solid var(--learn-line); border-radius: 5px; background: var(--learn-panel); color: var(--learn-ink); font: inherit; font-size: 11px; }
.bt-lab__mark-role:focus-visible { outline: 3px solid var(--learn-accent); outline-offset: 2px; }
.bt-lab__mark button { min-height: 44px; padding: 5px; border: 0; border-radius: 5px; background: transparent; color: var(--learn-muted); font: inherit; font-size: 11px; cursor: pointer; }
.bt-lab__mark button:first-child { display: grid; gap: 2px; text-align: left; }
.bt-lab__mark button:first-child strong { color: var(--learn-ink); font-size: 11px; }
.bt-lab__mark button[aria-pressed="true"] { background: rgba(255,157,55,.1); }
.bt-lab__mark button:hover { background: var(--learn-panel); }
.bt-lab__rules { display: grid; min-width: 0; gap: 6px; margin: 0; padding: 0; border: 0; }
.bt-lab__rules legend { margin-bottom: 8px; color: var(--learn-muted); font-size: 11px; }
.bt-lab__rules label { display: flex; align-items: center; gap: 7px; min-height: 44px; font-size: 12px; }
.bt-lab__rules input { accent-color: #ff9d37; }
.bt-lab__note { color: var(--learn-muted); font-size: 11px; }
.bt-lab__note summary { padding: 6px 0; cursor: pointer; }
.bt-lab__note textarea, .bt-lab__field select { width: 100%; min-height: 44px; margin-top: 7px; padding: 8px; border: 1px solid var(--learn-line); border-radius: 7px; background: var(--learn-panel); color: var(--learn-ink); font: inherit; font-size: 12px; resize: vertical; }
.bt-lab__drawing-tools button:focus-visible, .bt-lab__checklist button:focus-visible, .bt-lab__mark button:focus-visible, .bt-lab__coach button:focus-visible, .bt-lab__note summary:focus-visible, .bt-lab__note textarea:focus-visible, .bt-lab__field select:focus-visible, .bt-lab__rules input:focus-visible, .bt-lab__actions input:focus-visible { outline: 3px solid rgba(255,154,49,.5); outline-offset: 2px; }
.bt-lab__workspace:fullscreen { display: block; width: 100%; height: 100svh; border-radius: 0; overflow-y: auto; }
.bt-lab__workspace:fullscreen .bt-lab__main { min-height: 100svh; height: auto; }
.bt-lab__workspace:fullscreen .bt-lab__casebar .bt-learn__eyebrow, .bt-lab__workspace:fullscreen .bt-lab__select-label, .bt-lab__workspace:fullscreen .bt-lab__metadata { display: none; }
.bt-lab__workspace:fullscreen .bt-lab__casebar h2 { font-size: 18px; }
.bt-lab__workspace:fullscreen .bt-lab__task { margin: 8px 0; padding: 8px 12px; }
.bt-lab__workspace:fullscreen .bt-lab__transport { gap: 6px; padding: 6px; }
.bt-lab__workspace:fullscreen .bt-lab__transport { flex-wrap: nowrap; flex-shrink: 0; min-height: 58px; overflow-x: auto; }
.bt-lab__workspace:fullscreen .bt-lab__transport > * { flex-shrink: 0; }
.bt-lab__workspace:fullscreen .bt-lab__transport-actions { width: auto; flex-wrap: nowrap; }
.bt-lab__workspace:fullscreen .bt-lab__transport button { padding: 7px 8px; font-size: 11px; }
.bt-lab__workspace:fullscreen .bt-lab__drawing-tools { flex-wrap: nowrap; overflow-x: auto; min-height: 49px; }
.bt-lab__workspace:fullscreen .bt-lab__drawing-tools button { flex: 0 0 auto; }
.bt-lab__workspace:fullscreen .bt-lab__tool-hint { min-height: 32px; }
.bt-lab__workspace:fullscreen .bt-lab__task { display: flex; align-items: baseline; }
.bt-lab__workspace:fullscreen .bt-lab__task p { margin: 0; font-size: 12px; line-height: 1.4; }
.bt-lab__workspace:fullscreen .bt-lab__chart-shell { flex: 0 0 auto; height: clamp(320px,55svh,700px); min-height: 220px; }
.bt-lab__workspace:fullscreen .bt-lab__decision { overflow-y: auto; }
.bt-lab__panel-head h2 { margin: 0; font-size: 23px; letter-spacing: -.03em; }
.bt-lab__actions { display: grid; gap: 8px; margin: 0; padding: 0; border: 0; }
.bt-lab__actions legend { margin-bottom: 9px; color: var(--learn-muted); font-size: 12px; font-weight: 800; }
.bt-lab__actions label { display: flex; gap: 9px; align-items: center; min-height: 44px; padding: 8px 11px; border: 1px solid var(--learn-line); border-radius: 8px; background: var(--learn-panel); cursor: pointer; font-size: 12px; font-weight: 700; }
.bt-lab__actions label:has(input:checked) { border-color: var(--learn-accent); }
.bt-lab__actions input { accent-color: #ff9d37; }
.bt-lab__field { display: grid; gap: 7px; margin-bottom: 13px; font-size: 12px; font-weight: 800; }
.bt-lab__field small { color: var(--learn-soft); font-size: 10px; font-weight: 600; }
.bt-lab__field input, .bt-lab__field textarea { width: 100%; min-height: 37px; padding: 10px; border: 1px solid var(--learn-line); border-radius: 8px; background: var(--learn-panel); color: var(--learn-ink); font: inherit; font-size: 12px; font-weight: 500; line-height: 1.45; resize: vertical; }
.bt-lab__field input::placeholder, .bt-lab__field textarea::placeholder { color: var(--learn-soft); }
.bt-lab__level-state { margin: -5px 0 13px; color: var(--learn-soft); font-size: 11px; line-height: 1.4; }
.bt-lab__decision .bt-learn__primary { width: 100%; }
.bt-lab__decision .bt-learn__primary:disabled { cursor: not-allowed; }
.bt-lab__next-step { margin: -9px 0 0; color: var(--learn-muted); font-size: 11px; line-height: 1.45; }
.bt-lab__boundary { margin: 0; color: var(--learn-soft); font-size: 11px; line-height: 1.45; }
.bt-lab__review { display: grid; align-content: start; gap: 19px; }
.bt-lab__review p { margin: 0; color: var(--learn-muted); font-size: 13px; }
.bt-lab__review ul { display: grid; gap: 9px; max-height: 320px; overflow-y: auto; margin: 0; padding: 0 4px 0 17px; color: var(--learn-ink); font-size: 13px; }
.bt-lab__market-facts { display: grid; gap: 9px; padding: 13px; border: 1px solid var(--learn-line); border-radius: 9px; background: var(--learn-panel); }
.bt-lab__market-facts p { color: var(--learn-ink); font-size: 12px; }
.bt-lab__review .bt-learn__secondary { width: max-content; }
.bt-lab__below { display: grid; grid-template-columns: 1fr; gap: 17px; margin-top: 17px; }
.bt-lab__case-list { display: grid; grid-template-columns: repeat(2,minmax(0,1fr)); gap: 8px; }
.bt-lab__case-row { display: grid; gap: 3px; align-content: center; min-height: 63px; border: 1px solid var(--learn-line); border-radius: 9px; padding: 10px 12px; background: var(--learn-panel-2); color: var(--learn-ink); text-align: left; text-decoration: none; font: inherit; cursor: pointer; }
.bt-lab__case-row:hover { border-color: var(--learn-accent); }
.bt-lab__case-row strong { font-size: 12px; }
.bt-lab__case-row span { color: var(--learn-muted); font-size: 11px; }
.bt-lab__metrics { display: grid; grid-template-columns: repeat(4,minmax(0,1fr)); gap: 8px; }
.bt-lab__metrics > div { display: grid; gap: 5px; padding: 12px; border: 1px solid var(--learn-line); border-radius: 8px; background: var(--learn-panel-2); }
.bt-lab__metrics strong { font-size: 22px; line-height: 1; }
.bt-lab__metrics span { color: var(--learn-muted); font-size: 10px; line-height: 1.25; }
.bt-lab__analysis-line { margin: 17px 0 10px; font-size: 12px; line-height: 1.5; }
.bt-lab__recent { display: grid; gap: 7px; margin-top: 14px; padding-top: 12px; border-top: 1px solid var(--learn-line); }
.bt-lab__recent a { font-size: 12px; text-decoration: none; }
.bt-lab__recent a:hover { color: var(--learn-accent); }

.bt-learn-hub__workspace { display: grid; grid-template-columns: minmax(0,1.7fr) minmax(280px,.75fr); overflow: hidden; border: 1px solid var(--learn-line); border-radius: 18px; background: var(--learn-panel); box-shadow: 0 20px 50px rgba(0,0,0,.12); }
.bt-learn-hub__preview { display: flex; flex-direction: column; min-width: 0; padding: clamp(20px,2.3vw,32px); }
.bt-learn-hub__topline { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 10px; }
.bt-learn-hub__state { color: var(--learn-muted); font-size: 11px; font-weight: 800; }
.bt-learn-hub__preview h2 { margin: 4px 0 8px; font-size: clamp(23px,2.25vw,34px); letter-spacing: -.035em; line-height: 1.15; }
.bt-learn-hub__preview > p { max-width: 670px; margin: 0 0 19px; color: var(--learn-muted); font-size: 13px; }
.bt-learn-hub__chart-wrap { min-height: 355px; overflow: hidden; border: 1px solid var(--learn-line); border-radius: 11px; background: var(--learn-chart); }
.bt-learn-hub__chart { position: relative; height: 355px; width: 100%; }
.bt-learn-hub__chart-fallback { display: grid; place-items: center; min-height: 355px; padding: 20px; color: var(--learn-muted); text-align: center; font-size: 13px; }
.bt-learn-hub__preview-foot { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 6px 14px; margin: 9px 0 19px; color: var(--learn-soft); font-size: 11px; }
.bt-learn-hub__preview .bt-learn__primary { align-self: flex-start; min-width: 178px; }
.bt-learn-hub__rail { display: flex; flex-direction: column; border-left: 1px solid var(--learn-line); background: var(--learn-panel-2); }
.bt-learn-hub__rail-section { padding: clamp(21px,2.2vw,30px); border-bottom: 1px solid var(--learn-line); }
.bt-learn-hub__rail-section h3 { margin: 0 0 8px; font-size: clamp(17px,1.55vw,22px); line-height: 1.2; letter-spacing: -.02em; }
.bt-learn-hub__rail-section p { margin: 0 0 19px; color: var(--learn-muted); font-size: 12px; line-height: 1.5; }
.bt-learn-hub__access { display: grid; gap: 4px; margin-top: auto; padding: 20px clamp(21px,2.2vw,30px); color: var(--learn-muted); font-size: 11px; }
.bt-learn-hub__access strong { color: var(--learn-ink); font-size: 12px; }
.bt-learn-hub__follow { display: grid; grid-template-columns: minmax(0,1.7fr) minmax(280px,.75fr); gap: 17px; margin-top: 17px; }
.bt-learn-hub__follow-main, .bt-learn-hub__activity { padding: clamp(18px,2vw,25px); border: 1px solid var(--learn-line); border-radius: 14px; background: var(--learn-panel); }
.bt-learn-hub__follow-main p { margin: 0; color: var(--learn-muted); font-size: 13px; }
.bt-learn-hub__links { display: flex; flex-wrap: wrap; gap: 9px 20px; margin-top: 17px; }
.bt-learn-hub__links a { font-size: 12px; font-weight: 800; text-decoration: underline; text-decoration-color: var(--learn-accent); text-underline-offset: 4px; }
.bt-learn-hub__links a:hover { color: var(--learn-accent); }
.bt-learn-hub__activity { display: grid; align-content: start; gap: 7px; }
.bt-learn-hub__activity strong { font-size: 19px; line-height: 1.2; }
.bt-learn-hub__activity > span:last-child { color: var(--learn-muted); font-size: 12px; }

.bt-learn-analysis { display: grid; gap: 16px; }
.bt-learn-analysis__empty { max-width: 700px; padding: clamp(24px,3vw,38px); }
.bt-learn-analysis__empty h2 { margin: 0 0 9px; font-size: clamp(21px,2.4vw,30px); }
.bt-learn-analysis__empty p { margin: 0 0 21px; color: var(--learn-muted); }
.bt-learn-analysis__summary { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); gap: 12px; }
.bt-learn-analysis__summary > div { display: grid; gap: 5px; border: 1px solid var(--learn-line); border-radius: 12px; padding: 17px; background: var(--learn-panel); }
.bt-learn-analysis__summary strong { font-size: clamp(24px,2.5vw,35px); line-height: 1; }
.bt-learn-analysis__summary span { color: var(--learn-muted); font-size: 12px; }
.bt-learn-analysis__summary p { grid-column: 1/-1; margin: 0; color: var(--learn-muted); font-size: 12px; }
.bt-learn-analysis__skill-list { display: grid; }
.bt-learn-analysis__skill { display: grid; grid-template-columns: minmax(0,1fr) minmax(190px,.85fr); align-items: start; gap: 12px 25px; padding: 17px 0; border-top: 1px solid var(--learn-line); }
.bt-learn-analysis__skill h3 { margin: 0 0 5px; font-size: 16px; }
.bt-learn-analysis__skill p { margin: 0; color: var(--learn-muted); font-size: 13px; }
.bt-learn-analysis__skill-action { display: grid; gap: 7px; justify-items: start; }
.bt-learn-analysis__skill-action a { font-size: 12px; text-decoration: underline; text-decoration-color: var(--learn-accent); text-underline-offset: 3px; }
.bt-learn-analysis__skill-action a:last-child { color: var(--learn-accent); font-weight: 800; }
.bt-learn-analysis__boundary { margin: 12px 0 0; color: var(--learn-soft); font-size: 12px; }
.bt-learn-analysis__recent { display: grid; }
.bt-learn-analysis__recent a { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 6px 18px; padding: 13px 0; border-top: 1px solid var(--learn-line); text-decoration: none; font-size: 12px; }
.bt-learn-analysis__recent a:hover strong { color: var(--learn-accent); }
.bt-learn-analysis__recent span { color: var(--learn-muted); }

@media (max-width: 1050px) {
  .bt-lab__workspace { grid-template-columns: minmax(0,1fr); }
  .bt-lab__below { grid-template-columns: 1fr; }
  .bt-learn-hub__workspace, .bt-learn-hub__follow { grid-template-columns: minmax(0,1fr) 290px; }
}
@media (max-width: 900px) {
  .bt-lab__cases-grid { grid-template-columns: repeat(3,minmax(0,1fr)); }
  .bt-lab__workspace { grid-template-columns: minmax(0,1fr); }
  .bt-lab__decision { border-left: 0; border-top: 1px solid var(--learn-line); }
  .bt-lab__decision form { grid-template-columns: minmax(0,1fr); }
  .bt-lab__workspace:fullscreen { display: block; overflow-y: auto; }
  .bt-lab__workspace:fullscreen .bt-lab__main { min-height: 100svh; height: auto; }
}
@media (max-width: 760px) {
  .bt-lab__navigation { padding: 12px; }
  .bt-lab__selector-bar { flex-wrap: wrap; gap: 4px; }
  .bt-lab__selector-bar .bt-lab__levels { flex-basis: 100%; }
  .bt-lab__cases-toggle { margin-left: auto; }
  .bt-lab__cases-grid { grid-template-columns: repeat(2,minmax(0,1fr)); }
  .bt-lab__level-hint { max-width: none; }
  .bt-lab__overview { flex-wrap: wrap; gap: 4px 12px; margin-bottom: 12px; }
  .bt-lab__overall { order: 1; flex-basis: 100%; }
  .bt-lab__overall progress { flex: 1; }
  .bt-lab__level { padding: 9px 8px; }
  .bt-lab__casebar { align-items: stretch; flex-direction: column; }
  .bt-lab__select-label { min-width: 0; }
  .bt-lab__chart-shell { height: clamp(350px,55svh,520px); }
  .bt-lab__task { display: block; }
  .bt-lab__task p { margin-top: 6px; }
  .bt-learn-hub__workspace, .bt-learn-hub__follow { grid-template-columns: 1fr; }
  .bt-learn-hub__rail { border-left: 0; border-top: 1px solid var(--learn-line); }
}
@media (max-width: 520px) {
  .bt-lab__level-heading { flex-direction: column; align-items: flex-start; gap: 4px; }
  .bt-lab__level-goal { display: none; }
  .bt-lab__level-short { display: block; }
  .bt-lab__navigation[data-collapsed="true"] .bt-lab__level { padding-inline: 7px; }
  .bt-lab__level strong { font-size: 12px; }
  .bt-lab__filters { width: 100%; }
  .bt-lab__filters button { flex: 1; padding-inline: 5px; font-size: 11px; }
  .bt-lab__filters button > span { margin-left: 3px; }
  .bt-lab__case-card { padding: 11px; }
  .bt-lab__phases { gap: 8px 12px; }
  .bt-lab__notice { min-height: 60px; }
  .bt-lab__case-list { grid-template-columns: 1fr; }
  .bt-lab__metrics { grid-template-columns: repeat(2,minmax(0,1fr)); }
  .bt-lab__metadata span + span { padding-left: 0; border-left: 0; }
  .bt-lab__chart-shell { height: 380px; }
  .bt-lab__coach { width: calc(100% - 24px); padding: 8px 10px; }
  .bt-lab__coach p { font-size: 13px; }
  .bt-lab__coach-title small, .bt-lab__coach .bt-lab__coach-focus { display: none; }
  .bt-lab__coach-name { font-size: 12px; }
  .bt-lab__coach-head { gap: 3px; margin-bottom: 7px; padding-bottom: 4px; }
  .bt-lab__coach-step { margin-top: 7px; }
  .bt-lab__drawing-tools { flex-wrap: nowrap; overflow-x: auto; min-height: 49px; flex-shrink: 0; }
  .bt-lab__drawing-tools button { flex: 0 0 auto; }
  .bt-lab__tool-hint, .bt-lab__workspace:fullscreen .bt-lab__tool-hint { height: auto; min-height: 0; }
  .bt-lab__decision form { display: grid; }
  .bt-lab__transport-actions { width: 100%; }
  .bt-lab__transport-actions { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); }
  .bt-lab__transport-actions button { flex: 1 1 auto; }
  .bt-lab__transport .bt-lab__transport-primary { min-width: 0; }
  .bt-lab__transport-actions button { min-width: 0; padding: 7px 5px; font-size: 11px; white-space: normal; }
  .bt-lab__workspace:fullscreen .bt-lab__transport-actions { display: flex; }
  .bt-lab__progress { width: 100%; margin-left: 0; }
  .bt-learn-hub__chart-wrap, .bt-learn-hub__chart, .bt-learn-hub__chart-fallback { min-height: 275px; height: 275px; }
  .bt-learn-analysis__summary { grid-template-columns: 1fr; }
  .bt-learn-analysis__skill { grid-template-columns: 1fr; }
}

/* One answer form follows the coach; only its active step is shown on the canvas. */
.bt-lab__coach[data-mode="answer"], .bt-lab__coach[data-mode="review"] { width: min(480px,calc(100% - 24px)); }
.bt-lab__chart-shell:has(.bt-lab__coach[data-mode="answer"]:not([hidden])) { min-height: 520px; }
.bt-lab__coach-form form { display: grid; gap: 14px; min-width: 0; }
.bt-lab__coach-form .bt-lab__answer-head { display: none; }
[data-lab-form-home] .bt-lab__answer-footer { display: none; }
.bt-lab__coach-form .bt-lab__answer-panel, .bt-lab__coach-form .bt-lab__answer-panel .bt-lab__evidence { grid-template-columns: minmax(0,1fr); gap: 12px; }
.bt-lab__coach-form .bt-lab__actions { grid-template-columns: repeat(3,minmax(0,1fr)); gap: 6px; }
.bt-lab__coach-form .bt-lab__actions label { min-height: 44px; padding: 10px 8px; }
.bt-lab__coach-form fieldset { min-width: 0; }
.bt-lab__coach-form .bt-lab__answer-footer { grid-template-columns: minmax(0,1fr); gap: 8px; }
.bt-lab__coach-form .bt-lab__answer-footer .bt-learn__primary { grid-column: 1; grid-row: 1; width: 100%; min-width: 0; min-height: 44px; }
.bt-lab__coach-form .bt-lab__next-step { display: none; }
.bt-lab__coach-form .bt-lab__answer-footer .bt-lab__boundary { grid-row: 2; }
.bt-lab__coach .bt-lab__boundary, .bt-lab__coach .bt-lab__coach-plan { margin: 0 0 10px; font-size: 11px; line-height: 1.55; font-weight: 400; color: var(--learn-muted); }
.bt-lab__coach .bt-lab__coach-plan[data-state="inside-area"], .bt-lab__coach .bt-lab__coach-plan[data-state="wrong-side"] { color: var(--learn-accent); }
.bt-lab__coach .bt-lab__coach-error { color: var(--learn-accent); font-size: 12px; font-weight: 500; }
.bt-lab__coach-review-nav { display: flex; align-items: center; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
.bt-lab__coach-review-nav > button { min-height: 44px; }
.bt-lab__coach-review-nav > button:first-child { padding: 8px 12px; border: 1px solid var(--learn-line); border-radius: 7px; background: var(--learn-panel); color: var(--learn-muted); font: inherit; font-size: 12px; cursor: pointer; }
.bt-lab__coach-review-nav > button:disabled { opacity: .45; cursor: default; }
.bt-lab__coach-completion .bt-lab__review-actions { margin-top: 10px; }
.bt-lab__coach-completion button { min-height: 44px; width: 100%; }
.bt-lab__case-info > summary::after { margin-left: 0; }
.bt-lab__comparison, .bt-lab__review, .bt-lab__author-review { display: block; }
.bt-lab__decision:has([data-lab-answer][hidden]):has([data-lab-review][hidden]) { display: none; }
.bt-lab__comparison > summary, .bt-lab__review > summary, .bt-lab__author-review > summary { display: flex; align-items: center; min-height: 44px; color: var(--learn-muted); font-size: 12px; cursor: pointer; list-style: none; }
.bt-lab__comparison > summary::after, .bt-lab__review > summary::after, .bt-lab__author-review > summary::after { content: "+"; margin-left: auto; }
.bt-lab__comparison[open] > summary::after, .bt-lab__review[open] > summary::after, .bt-lab__author-review[open] > summary::after { content: "−"; }
.bt-lab__comparison > summary:focus-visible, .bt-lab__review > summary:focus-visible, .bt-lab__author-review > summary:focus-visible { outline: 2px solid var(--learn-accent); outline-offset: 3px; }
@media (max-width: 520px) {
  .bt-lab__chart-shell:has(.bt-lab__coach[data-mode="answer"]:not([hidden])) { min-height: 580px; }
  .bt-lab__coach-form .bt-lab__actions { grid-template-columns: minmax(0,1fr); }
}
/* Local lab composition: chart first, compact answer panels, trainer on the canvas. */
.bt-lab__answer-head { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 12px; }
.bt-lab__answer-head h2 { margin: 0; font-size: 18px; }
.bt-lab__answer-tabs { display: flex; flex-wrap: wrap; gap: 6px; }
.bt-lab__answer-tabs button { min-height: 44px; padding: 9px 15px; border: 1px solid var(--learn-line); border-radius: 8px; background: var(--learn-panel); color: var(--learn-muted); font: inherit; font-size: 12px; cursor: pointer; }
.bt-lab__answer-tabs button[aria-pressed="true"] { border-color: var(--learn-accent); color: var(--learn-accent); }
.bt-lab__answer-tabs button:focus-visible, .bt-lab__review-details summary:focus-visible { outline: 2px solid var(--learn-accent); outline-offset: 3px; }
.bt-lab__note summary::after, .bt-lab__review-details summary::after, .bt-lab__author-review summary::after { content: "+"; margin-left: auto; padding-left: 12px; color: var(--learn-muted); font-size: 18px; }
.bt-lab__note[open] summary::after, .bt-lab__review-details[open] summary::after, .bt-lab__author-review details[open] summary::after { content: "−"; }
.bt-lab__answer-panel { display: grid; grid-template-columns: repeat(2,minmax(0,1fr)); align-items: start; gap: 16px 24px; }
.bt-lab__answer-panel .bt-lab__field { margin: 0; }
.bt-lab__answer-panel .bt-lab__checklist { grid-template-columns: repeat(2,minmax(0,1fr)); gap: 12px; }
.bt-lab__answer-panel [data-lab-plan-fields], .bt-lab__answer-panel .bt-lab__actions { grid-column: 1/-1; }
.bt-lab__answer-panel .bt-lab__actions { grid-template-columns: repeat(3,minmax(0,1fr)); }
.bt-lab__answer-panel .bt-lab__rules { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 20px; }
.bt-lab__answer-panel .bt-lab__rules legend { width: 100%; }
.bt-lab__answer-panel .bt-lab__evidence { grid-template-columns: repeat(2,minmax(0,1fr)); }
.bt-lab__answer-panel .bt-lab__evidence > p { grid-column: 1/-1; }
.bt-lab__answer-panel .bt-lab__note summary { display: flex; align-items: center; min-height: 44px; }
.bt-lab__answer-footer { display: grid; grid-template-columns: minmax(0,1fr) auto; gap: 8px 24px; align-items: center; padding-top: 12px; border-top: 1px solid var(--learn-line); }
.bt-lab__answer-footer .bt-lab__next-step { margin: 0; }
.bt-lab__answer-footer .bt-lab__boundary { grid-column: 1/-1; margin: 0; }
.bt-lab__answer-footer .bt-learn__primary { grid-column: 2; grid-row: 1; width: auto; min-width: 220px; }
.bt-lab__review-details summary { display: flex; align-items: center; min-height: 44px; color: var(--learn-muted); font-size: 13px; cursor: pointer; }
@media (max-width: 700px) {
  .bt-lab__answer-panel { grid-template-columns: minmax(0,1fr); gap: 14px; }
  .bt-lab__answer-panel .bt-lab__actions { grid-template-columns: minmax(0,1fr); }
  .bt-lab__answer-panel .bt-lab__evidence { grid-template-columns: minmax(0,1fr); }
  .bt-lab__answer-footer { grid-template-columns: minmax(0,1fr); }
  .bt-lab__answer-footer .bt-learn__primary { grid-column: 1; grid-row: 2; min-width: 0; width: 100%; }
  .bt-lab__answer-footer .bt-lab__boundary { grid-row: 3; }
}

/* Guidance controls disclose detail after the learner chooses a task. */
.bt-lab__case-info { min-width: 0; max-width: 850px; margin-top: 6px; }
.bt-lab__case-info summary { justify-content: flex-start; width: fit-content; gap: 12px; }
.bt-lab__case-info summary::after { margin-left: 0; }
.bt-lab__case-info summary, .bt-lab__options summary, .bt-lab__toolbox summary, .bt-lab__answer > summary { display: flex; align-items: center; gap: 12px; min-height: 44px; color: var(--learn-muted); font-size: 12px; cursor: pointer; list-style: none; }
.bt-lab__case-info summary::after, .bt-lab__options summary::after, .bt-lab__toolbox summary::after, .bt-lab__answer > summary::after { content: "+"; margin-left: auto; color: var(--learn-soft); font-size: 18px; }
.bt-lab__case-info[open] summary::after, .bt-lab__options[open] summary::after, .bt-lab__toolbox[open] summary::after, .bt-lab__answer[open] > summary::after { content: "−"; }
.bt-lab__case-info summary::-webkit-details-marker, .bt-lab__options summary::-webkit-details-marker, .bt-lab__toolbox summary::-webkit-details-marker, .bt-lab__answer > summary::-webkit-details-marker { display: none; }
.bt-lab__case-info-content { padding: 0 0 8px; }
.bt-lab__case-info .bt-lab__metadata { display: flex; flex-wrap: wrap; gap: 6px 16px; margin: 10px 0 0; }
.bt-lab__case-info .bt-lab__metadata span { padding: 0; border: 0; }
.bt-lab__case-goal { margin: 0; font-size: 12px; line-height: 1.6; }
.bt-lab__options { min-width: 0; }
.bt-lab__options summary { padding: 0 8px; }
.bt-lab__options[open] { flex: 1 1 100%; }
.bt-lab__options-content { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 12px; padding: 10px 0; }
.bt-lab__transport[data-coach="true"] .bt-lab__transport-primary { border-color: var(--learn-line); color: var(--learn-ink); }
.bt-lab__chart-label { color: var(--learn-soft); font-size: 11px; }
.bt-lab__toolbox { margin: 0; }
.bt-lab__toolbox summary { justify-content: flex-start; }
.bt-lab__toolbox summary::after { margin-left: 0; }
.bt-lab__toolbox small, .bt-lab__answer > summary small { color: var(--learn-soft); font-size: 11px; font-weight: 400; }
.bt-lab__toolbox .bt-lab__drawing-tools { flex-wrap: wrap; padding: 7px 0; overflow: visible; }
.bt-lab__transport .bt-lab__toolbox summary { padding: 0 8px; }
.bt-lab__transport .bt-lab__toolbox[open] { flex: 1 1 100%; order: 1; }
.bt-lab__transport .bt-lab__options[open] { order: 2; }
.bt-lab__answer > summary { flex-wrap: wrap; }
.bt-lab__answer[open] > summary { padding-bottom: 12px; margin-bottom: 16px; border-bottom: 1px solid var(--learn-line); }
.bt-lab__answer-head { justify-content: flex-start; }
.bt-lab__coach-name { text-transform: none; letter-spacing: 0; font-size: 11px; color: var(--learn-muted); }
.bt-lab__coach .bt-lab__coach-tip, .bt-lab__coach .bt-lab__coach-detail-text { margin: 8px 0; color: var(--learn-muted); font-size: 11px; font-weight: 400; line-height: 1.55; }
.bt-lab__coach .bt-lab__coach-detail { min-height: 44px; padding: 7px 8px; border: 0; background: transparent; color: var(--learn-muted); font: inherit; font-size: 11px; text-decoration: underline; text-underline-offset: 3px; cursor: pointer; }
.bt-lab__coach-rules { display: grid; grid-template-columns: repeat(2,minmax(0,1fr)); gap: 8px; }
.bt-lab__coach-rules button { min-height: 44px; padding: 8px; border: 1px solid var(--learn-line); border-radius: 7px; background: var(--learn-panel); color: var(--learn-ink); font: inherit; font-size: 12px; cursor: pointer; }
.bt-lab__case-info summary:focus-visible, .bt-lab__options summary:focus-visible, .bt-lab__toolbox summary:focus-visible, .bt-lab__answer > summary:focus-visible { outline: 2px solid var(--learn-accent); outline-offset: 3px; border-radius: 4px; }
@media (max-width: 700px) {
  .bt-lab__case-info { width: 100%; max-width: none; flex-basis: auto; }
  .bt-lab__answer > summary small { flex-basis: 100%; }
  .bt-lab__answer > summary::after { position: absolute; right: 0; }
  .bt-lab__answer > summary { position: relative; padding-right: 24px; }
  .bt-lab__workspace:fullscreen .bt-lab__transport { flex-wrap: wrap; overflow: visible; }
}
@media (max-width: 520px) {
  .bt-lab__transport { gap: 6px 10px; }
  .bt-lab__transport-actions { width: auto; grid-template-columns: repeat(2,minmax(0,1fr)); }
  .bt-lab__chart-label { margin-left: auto; }
  .bt-lab__toolbox small { max-width: 65%; overflow-wrap: anywhere; }
}