@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 .kg-box {background:var(--card);border:1.5px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow-card);overflow:hidden}.legacy-content .kg-stage {padding:10px 12px 4px;display:flex;justify-content:center}.legacy-content .kg-stage svg {width:100%;max-width:660px;height:auto;display:block}.legacy-content .kg-edge {stroke:rgba(0,0,0,.14);stroke-width:1.5;transition:stroke .3s,stroke-width .3s}.legacy-content .kg-edge.lit {stroke:var(--ds);stroke-width:2.5}.legacy-content .kg-elabel {fill:var(--sub);font-size:9.5px;font-weight:600;opacity:.75}.legacy-content .kg-node {cursor:pointer;transition:opacity .3s}.legacy-content .kg-node circle.kg-dot {stroke:#fff;stroke-width:2;transition:r .25s}.legacy-content .kg-node text {fill:var(--text);font-size:12px;font-weight:800;pointer-events:none}.legacy-content .kg-node.dim {opacity:.22}.legacy-content .kg-node.h0 circle.kg-dot {r:15}.legacy-content .kg-ring {fill:none;stroke-width:2.5;opacity:0;pointer-events:none}.legacy-content .kg-node.h0 .kg-ring, .legacy-content .kg-node.h1 .kg-ring, .legacy-content .kg-node.h2 .kg-ring {animation:kgRipple .7s ease-out}@keyframes kgRipple{0%{opacity:.85;transform:scale(1)}100%{opacity:0;transform:scale(2.6)}}.legacy-content .kg-hop {fill:#fff;font-size:9px;font-weight:900;pointer-events:none;opacity:0;transition:opacity .3s}.legacy-content .kg-node.h0 .kg-hop, .legacy-content .kg-node.h1 .kg-hop, .legacy-content .kg-node.h2 .kg-hop {opacity:1}.legacy-content .kg-legend {display:flex;gap:14px;flex-wrap:wrap;padding:10px 22px;font-size:12px;color:var(--sub);border-bottom:1px solid var(--border);background:rgba(0,0,0,.015)}.legacy-content .kg-legend i {display:inline-block;width:10px;height:10px;border-radius:50%;margin-right:5px;vertical-align:-1px}.legacy-content .kg-narr {margin:8px 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 .kg-narr b {color:var(--ds-deep)}.legacy-content .dag-box {background:var(--card);border:1.5px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow-card);overflow:hidden}.legacy-content .dag-stage {padding:12px 12px 4px;display:flex;justify-content:center}.legacy-content .dag-stage svg {width:100%;max-width:760px;height:auto;display:block}.legacy-content .dag-edge {stroke:rgba(0,0,0,.2);stroke-width:2;fill:none;transition:stroke .3s}.legacy-content .dag-edge.lit {stroke:var(--success)}.legacy-content .dag-edge.cycle {stroke:var(--danger);stroke-dasharray:6 5;opacity:0;transition:opacity .4s}.legacy-content .dag-edge.cycle.on {opacity:1}.legacy-content .dag-node rect {fill:#fff;stroke:rgba(0,0,0,.18);stroke-width:1.5;transition:fill .3s,stroke .3s}.legacy-content .dag-node text {fill:var(--text);font-size:12.5px;font-weight:800;pointer-events:none}.legacy-content .dag-node.running rect {fill:var(--muted);stroke:var(--amber);animation:dagPulse .8s ease-in-out infinite}@keyframes dagPulse{50%{stroke-width:3.5}}.legacy-content .dag-node.done rect {fill:var(--muted);stroke:var(--success)}.legacy-content .dag-node.done text {fill:var(--surface-soft)}.legacy-content .dag-node.stuck rect {fill:var(--muted);stroke:var(--danger);animation:dagBlink .5s step-end infinite}@keyframes dagBlink{50%{fill:#fff}}.legacy-content .dag-narr {margin:8px 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 .dag-narr b {color:var(--ds-deep)}.legacy-content .dag-narr .warn {color:var(--danger);font-weight:800}.legacy-content .dag-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-ghost {background:none;color:var(--danger);border:1.5px solid rgba(220,38,38,.4);padding:9px 22px;border-radius:999px;font-size:13.5px;font-weight:800;cursor:pointer;font-family:inherit;transition:background .15s}.legacy-content .btn-ghost:hover:not(:disabled) {background:rgba(220,38,38,.06)}.legacy-content .btn-ghost:disabled {opacity:.45;cursor:not-allowed}.legacy-content .btn-ghost.armed {background:var(--danger);color:#fff;border-color:var(--danger)}.legacy-content .dag-status {font-size:12.5px;color:var(--sub);font-weight:600}.legacy-content .concept-grid {display:grid;grid-template-columns:1fr 1fr;gap:14px}.legacy-content .concept-card {background:var(--card);border:1.5px solid var(--border);border-radius:var(--radius);padding:18px 20px;box-shadow:var(--shadow-card)}.legacy-content .concept-card .cc-icon {font-size:24px;margin-bottom:8px}.legacy-content .concept-card h4 {font-size:15px;font-weight:800;color:var(--text);margin-bottom:6px}.legacy-content .concept-card p {font-size:13px;color:var(--sub);line-height:1.75}.legacy-content .concept-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 .kg-node text {font-size:13px}.legacy-content .concept-grid {grid-template-columns:1fr}.legacy-content .kg-narr, .legacy-content .dag-narr {margin-left:14px;margin-right:14px}}

.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)}