/* RC173: consistent light, dim and dark learning surfaces. */
.sk173-map,.sk173-visual{--sk173-bg:#eaf4fc;--sk173-card:#fff;--sk173-edge:#b4cde1;--sk173-text:#173453;--sk173-muted:#45617e;--sk173-accent:#21658a;--sk173-soft:#dceefa;background:var(--sk173-bg);color:var(--sk173-text);border:1px solid var(--sk173-edge);border-radius:20px;padding:19px;margin:20px 0;max-width:100%;min-width:0;overflow-wrap:anywhere}
.sk173-map *,.sk173-visual *{box-sizing:border-box}
.sk173-map-head>span,.sk173-visual header>span{font-size:11px;font-weight:850;letter-spacing:.08em;color:var(--sk173-accent)}
.sk173-map-head h3,.sk173-visual header h3{margin:6px 0;font-size:clamp(19px,2.1vw,25px);line-height:1.3;color:var(--sk173-text)}
.sk173-map-head p,.sk173-visual header p{font-size:14px;color:var(--sk173-muted);line-height:1.65;margin:5px 0 16px}
.sk173-map-flow{display:grid;grid-template-columns:minmax(0,1fr) 22px minmax(0,1fr) 22px minmax(0,1fr);align-items:stretch;gap:7px}
.sk173-map-node{border:1px solid var(--sk173-edge);background:var(--sk173-card);border-radius:15px;padding:13px;min-width:0;display:flex;flex-direction:column;gap:8px}
.sk173-map-node small{font-weight:800;color:var(--sk173-accent);font-size:11px}.sk173-map-node strong{font-size:17px;line-height:1.4;color:var(--sk173-text)}.sk173-map-node p{font-size:13px;line-height:1.65;color:var(--sk173-muted);margin:0}
.sk173-map-arrow{display:grid;place-items:center;font-size:25px;font-weight:900;color:var(--sk173-accent)}
.sk173-map-why{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-top:12px}
.sk173-map-why details{min-width:0;background:var(--sk173-card);border:1px solid var(--sk173-edge);border-radius:12px;padding:11px}.sk173-map-why summary{font-weight:800;color:var(--sk173-text);cursor:pointer}.sk173-map-why details p{margin:12px 0 0;color:var(--sk173-muted);line-height:1.6}
.sk173-map-takeaway{border:1px solid var(--sk173-edge);background:var(--sk173-soft);border-radius:12px;padding:13px;font-weight:600;line-height:1.7;color:var(--sk173-text)}.sk173-map-note{font-size:12px;color:var(--sk173-muted)}
.sk173-visual-layout{display:grid;grid-template-columns:minmax(0,1.2fr) minmax(0,.8fr);gap:12px}.sk173-visual-stage,.sk173-visual-control{background:var(--sk173-card);border:1px solid var(--sk173-edge);border-radius:14px;padding:13px;min-width:0}
.sk173-visual-stage svg{width:100%;height:auto;display:block;color:var(--sk173-text)}
.sk173-visual-control{display:flex;flex-direction:column;justify-content:center;gap:12px}.sk173-visual-control label{font-weight:850;color:var(--sk173-text)}.sk173-visual-control input{width:100%;min-height:38px;accent-color:#2988ac;cursor:pointer}.sk173-visual-control output{font-weight:800;line-height:1.65;color:var(--sk173-text)}.sk173-visual-control p{font-size:13px;line-height:1.65;color:var(--sk173-muted);margin:0}
:is(html.lessonsky-dark body,body.lessonsky-dark) :is(.sk173-map,.sk173-visual){--sk173-bg:#142840;--sk173-card:#203c5a;--sk173-edge:#567897;--sk173-text:#f2f8ff;--sk173-muted:#c8d9ec;--sk173-accent:#a5d5ff;--sk173-soft:#294865}
:is(html.lessonsky-dim body,body.lessonsky-dim) :is(.sk173-map,.sk173-visual){--sk173-bg:#283f53;--sk173-card:#324f64;--sk173-edge:#6b8a9f;--sk173-text:#f4f8ff;--sk173-muted:#d3e1ee;--sk173-accent:#bee3ff;--sk173-soft:#426078}
@media(max-width:760px){.sk173-map,.sk173-visual{padding:13px}.sk173-map-flow{grid-template-columns:minmax(0,1fr)}.sk173-map-arrow{transform:rotate(90deg);min-height:16px}.sk173-map-why{grid-template-columns:1fr}.sk173-visual-layout{grid-template-columns:minmax(0,1fr)}.sk173-map-node{padding:12px}}
@media(forced-colors:active){.sk173-map,.sk173-visual,.sk173-map-node,.sk173-visual-stage,.sk173-visual-control{background:Canvas;color:CanvasText;border-color:CanvasText}}