@keyframes _si{from{opacity:0}to{opacity:1}}

.legacy-content .lesson-header .kicker {color:var(--ds)}.legacy-content .l-callout b {color:var(--ds)}.legacy-content .map-box {background:var(--card);border:1.5px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow-card);overflow:hidden}.legacy-content .map-stage {padding:8px;display:flex;justify-content:center}.legacy-content .map-stage svg {width:100%;max-width:640px;height:auto;display:block;touch-action:none}.legacy-content .sem-word circle {stroke:#fff;stroke-width:2}.legacy-content .sem-word text {fill:var(--text);font-size:12.5px;font-weight:800;pointer-events:none}.legacy-content .sem-halo-label {font-size:12px;font-weight:800;opacity:.55}.legacy-content .sem-line {stroke:var(--ds);stroke-width:1.5;stroke-dasharray:5 4;opacity:.75}.legacy-content .sem-line.first {stroke-width:2.5;stroke-dasharray:none;opacity:1}.legacy-content .sem-dist {fill:var(--ds-deep);font-size:11px;font-weight:800;paint-order:stroke;stroke:#fff;stroke-width:3}.legacy-content .sem-query {cursor:grab}.legacy-content .sem-query:active {cursor:grabbing}.legacy-content .sem-query circle {fill:var(--surface-soft);stroke:#fff;stroke-width:2.5}.legacy-content .sem-query text {fill:#fff;font-size:13px;font-weight:900;pointer-events:none}.legacy-content .sem-crown {font-size:16px;pointer-events:none}.legacy-content .map-narr {margin:4px 22px 18px;padding:13px 16px;background:var(--ds-soft);border:1.5px dashed var(--ds-line);border-radius:var(--radius-sm);font-size:13px;line-height:1.8;color:var(--sub);min-height:52px}.legacy-content .map-narr b {color:var(--ds-deep)}.legacy-content .race-box {background:var(--card);border:1.5px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow-card);overflow:hidden}.legacy-content .race-stage {padding:8px;display:flex;justify-content:center}.legacy-content .race-stage svg {width:100%;max-width:640px;height:auto;display:block}.legacy-content .race-pt {fill:rgba(0,0,0,.28);transition:fill .1s,r .1s}.legacy-content .race-pt.flash {fill:var(--danger)}.legacy-content .race-pt.visited {fill:rgba(220,38,38,.35)}.legacy-content .race-pt.hop {fill:var(--ds)}.legacy-content .race-pt.answer {fill:var(--success)}.legacy-content .race-target {fill:var(--amber)}.legacy-content .race-jump {stroke:var(--ds);stroke-width:2;fill:none;opacity:0;transition:opacity .3s}.legacy-content .race-jump.on {opacity:.85}.legacy-content .race-jump.high {stroke-width:3;stroke-dasharray:2 6;stroke-linecap:round}.legacy-content .race-jump.mid {stroke-width:2.2;stroke-dasharray:5 4}.legacy-content .race-jump.low {stroke-width:1.8}.legacy-content .race-layer-tag {fill:var(--ds-deep);font-size:11.5px;font-weight:800;opacity:0;transition:opacity .3s}.legacy-content .race-layer-tag.on {opacity:1}.legacy-content .race-panel {display:grid;grid-template-columns:1fr 1fr;gap:0;border-top:1px solid var(--border)}.legacy-content .race-cell {padding:14px 20px;text-align:center}.legacy-content .race-cell + .race-cell {border-left:1px solid var(--border)}.legacy-content .race-cell .rc-name {font-size:12px;font-weight:800;color:var(--sub)}.legacy-content .race-cell .rc-num {font-size:30px;font-weight:900;font-variant-numeric:tabular-nums;color:var(--text)}.legacy-content .race-cell.brute .rc-num.hot {color:var(--danger)}.legacy-content .race-cell.hnsw .rc-num.hot {color:var(--ds)}.legacy-content .race-cell .rc-sub {font-size:11.5px;color:var(--sub)}.legacy-content .race-narr {margin:12px 22px 0;padding:13px 16px;background:var(--ds-soft);border:1.5px dashed var(--ds-line);border-radius:var(--radius-sm);font-size:13px;line-height:1.8;color:var(--sub);min-height:52px}.legacy-content .race-narr b {color:var(--ds-deep)}.legacy-content .race-foot {display:flex;align-items:center;gap:12px;flex-wrap:wrap;padding:14px 22px}.legacy-content .btn-ds {background:var(--ds);color:#fff;border:none;padding:10px 26px;border-radius:999px;font-size:14px;font-weight:800;cursor:pointer;font-family:inherit;transition:filter .15s,transform .15s}.legacy-content .btn-ds:hover:not(:disabled) {filter:brightness(1.08);transform:translateY(-1px)}.legacy-content .btn-ds:disabled {background:#c4c8cf;cursor:not-allowed}.legacy-content .btn-ds.alt {background:var(--danger)}.legacy-content .race-status {font-size:12.5px;color:var(--sub);font-weight:600}.legacy-content .nn-grid {display:grid;grid-template-columns:repeat(3,1fr);gap:14px}.legacy-content .nn-card {background:var(--card);border:1.5px solid var(--border);border-radius:var(--radius);padding:18px 20px;box-shadow:var(--shadow-card)}.legacy-content .nn-card .nn-icon {font-size:24px;margin-bottom:8px}.legacy-content .nn-card h4 {font-size:14.5px;font-weight:800;color:var(--text);margin-bottom:6px}.legacy-content .nn-card p {font-size:13px;color:var(--sub);line-height:1.75}.legacy-content .nn-card p b {color:var(--ds-deep)}.legacy-content .takeaway-box {background:linear-gradient(135deg,#f0f9ff,#e0f2fe);border:1.5px solid #bae6fd;border-radius:var(--radius);padding:24px 28px;margin-top:36px}.legacy-content .takeaway-box h3 {font-size:17px;font-weight:800;color:var(--ds-deep);margin-bottom:10px}.legacy-content .takeaway-box ul {list-style:none;padding:0;margin:0}.legacy-content .takeaway-box li {font-size:14.5px;color:#0c4a6e;line-height:1.8;padding:4px 0 4px 22px;position:relative}.legacy-content .takeaway-box li::before {content:'';position:absolute;left:0;top:13px;width:8px;height:8px;border-radius:50%;background:var(--ds)}@media (max-width:768px){.legacy-content .nn-grid {grid-template-columns:1fr}.legacy-content .map-narr, .legacy-content .race-narr {margin-left:14px;margin-right:14px}.legacy-content .race-cell .rc-num {font-size:24px}}

.legacy-content .xa-tldr {margin:18px 0 4px;padding:14px 18px;background:rgba(0,102,255,0.04);border:1px solid rgba(0,102,255,0.16);border-radius:10px}.legacy-content .xa-tldr .xa-tldr-tag {display:block;font-size:11px;font-weight:800;letter-spacing:1px;color:var(--accent,#0066ff);margin-bottom:6px}.legacy-content .xa-tldr p {margin:0;font-size:15px;line-height:1.8;color:var(--text,#1f2937)}