/* Simple Learning Hub — LEARN section (chapter reading + interactive diagram viewer). See HANDOVER.md → "Learn section". */
@font-face{font-family:Poppins;font-weight:700;font-display:swap;src:url(/learn/a/poppins-700.woff2) format('woff2')}
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.lrn h1{font-size:1.45rem;line-height:1.25;margin:.3em 0 .2em}
.lrn .sub{color:var(--mut);margin:0 0 10px}
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.lrn .how{font-size:.9rem;background:var(--card);border:1px dashed var(--line);border-radius:10px;padding:8px 10px;margin:10px 0}
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a.cc.d3 .ic{background:#7b3fe4}
a.cc:hover,a.cc:focus-visible{background:rgba(255,210,31,.3)}
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#ktip b{color:#ffd21f}#ktip i{display:block;font-style:normal;opacity:.85;margin-top:3px}
/* diagram strip */
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.dcard{flex:0 0 138px;scroll-snap-align:start;border:1px solid var(--line);border-radius:12px;background:var(--card);color:var(--ink);text-decoration:none;padding:6px;font-size:.8rem;line-height:1.3;display:flex;flex-direction:column;gap:5px}
.dcard img{width:100%;aspect-ratio:1;object-fit:contain;background:#fff;border-radius:8px}
.dcard b{font-size:.8rem}.dcard small{color:var(--mut);font-size:.72rem}
.dgrid{display:grid;grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:10px}.dgrid .dcard{flex:none}
/* inline figure button inside notes */
.fig{display:flex;gap:10px;align-items:center;border:1px solid var(--line);background:var(--card);border-radius:12px;padding:8px;margin:12px 0;color:var(--ink);text-decoration:none}
.fig img{width:84px;height:84px;object-fit:contain;background:#fff;border-radius:8px;flex:none}
.fig b{display:block}.fig small{color:var(--mut)}.fig .go{margin-left:auto;font-weight:700;color:var(--link);white-space:nowrap;font-size:.85rem}
/* end blocks */
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.endc{display:flex;gap:12px;align-items:center;border:1px solid var(--line);border-radius:12px;background:var(--card);padding:12px;color:var(--ink);text-decoration:none}
.endc .e{font-size:1.6rem}.endc b{display:block}.endc small{color:var(--mut)}
.pn{display:flex;gap:8px;justify-content:space-between;margin:18px 0}.pn a{flex:1}
/* viewer */
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@media(min-width:800px){.lv{align-items:center}.lvp{height:92vh;border-radius:16px}}
.lvin{border:1px solid var(--line);border-radius:14px;overflow:hidden;background:var(--card);display:flex;flex-direction:column;height:min(88vh,820px)}
.lvh{display:flex;align-items:flex-start;gap:8px;padding:10px 12px 6px;border-bottom:1px solid var(--line)}
.lvh .t{flex:1;min-width:0}.lvh .t b{display:block;font-size:1rem;line-height:1.3}.lvh .t small{color:var(--mut);font-size:.76rem}
.lvb{border:1px solid var(--line);background:var(--card);color:var(--ink);border-radius:9px;min-width:38px;height:38px;font-size:1rem;font-weight:700;cursor:pointer;padding:0 9px}
.lvb[aria-pressed=true]{background:var(--y);color:#081c2c;border-color:var(--y)}
.lvg{display:flex;gap:6px;overflow-x:auto;padding:6px 10px;border-bottom:1px solid var(--line)}
.lvg button{flex:none;border:1px solid var(--line);background:var(--soft);color:var(--ink);border-radius:999px;padding:5px 11px;font-size:.8rem;font-weight:600;cursor:pointer}
.lvg button.on{background:#081c2c;color:#ffd21f;border-color:#081c2c}
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.lvc .cv{position:absolute;left:0;top:0;transform-origin:0 0;will-change:transform}
.lvc svg{display:block;width:100%;height:100%}
.lvz{position:absolute;right:6px;top:6px;display:flex;gap:5px}.lvz .lvb{min-width:34px;height:34px;padding:0 6px}
.lvz .lvb{background:rgba(255,255,255,.94);color:#081c2c;border-color:#cfd8de}
.lvs{display:flex;align-items:center;gap:6px;padding:7px 10px;border-top:1px solid var(--line);background:var(--soft)}
.lvs .cap{flex:1;font-size:.86rem;line-height:1.35;min-height:2.7em}
.lvs .n{font-size:.75rem;color:var(--mut);white-space:nowrap}
.lvi{padding:9px 12px;border-top:1px solid var(--line);font-size:.9rem;line-height:1.5;min-height:4.4em;max-height:34vh;overflow:auto}
.lvi .nm{font-weight:700;font-size:1rem}.lvi .hn{color:var(--mut);margin-left:6px}
.lvi .tip{color:var(--mut)}
.lvf{display:flex;gap:12px;flex-wrap:wrap;padding:6px 12px 10px;font-size:.8rem;border-top:1px solid var(--line)}
.lvf a{color:var(--link)}
.lvload{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;color:#56636e;font-size:.9rem}
/* svg states (the diagram's own colours live in each SVG) */
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@keyframes lvpulse{50%{opacity:.55}}
.lvc svg.nolbl .lb{display:none}
.lvc svg [data-s]{transition:opacity .45s}
.lvc svg .hid{opacity:0!important;pointer-events:none}
.quiz .lb text{fill:transparent}

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/* reading-language switch (English | हिंदी | Hinglish) */
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.lsw button.on{background:#0b3c5d;border-color:#0b3c5d;color:#fff}
.lsw button small{display:block;font-weight:500;font-size:.68rem;opacity:.8;margin-top:2px}
.lswh{font-size:.82rem;margin:-2px 0 10px;color:var(--mut,#56636e)}
/* tap-to-understand */
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.tb .trb{display:inline-flex;align-items:center;justify-content:center;width:30px;height:26px;margin-left:6px;vertical-align:middle;border:1.5px solid #ffb300;background:#fff8e1;color:#b26a00;border-radius:8px;font:700 .9rem/1 "Noto Sans Devanagari",system-ui,sans-serif;cursor:pointer;padding:0}
.box.tb .trb{position:absolute;top:8px;right:8px;margin:0}
.tb.trsel{background:#fff8e1;box-shadow:0 0 0 3px #fff8e1;border-radius:6px}
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#trsw.on{pointer-events:auto}
#trsbg{position:absolute;inset:0;background:rgba(8,28,44,.35);opacity:0;transition:opacity .2s}
#trsw.on #trsbg{opacity:1}
#trs{position:absolute;left:0;right:0;bottom:0;max-height:72vh;overflow:auto;background:var(--card,#fff);color:var(--ink,#14212b);border-radius:18px 18px 0 0;padding:12px 14px 18px;box-shadow:0 -8px 30px rgba(0,0,0,.25);transform:translateY(105%);transition:transform .22s ease-out}
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#trs .tabs button{flex:1;min-height:44px;border-radius:11px;border:2px solid #cfd8de;background:transparent;color:inherit;font:700 .95rem/1.1 system-ui,"Noto Sans Devanagari",sans-serif;cursor:pointer}
#trs .tabs button.on{background:#ffb300;border-color:#ffb300;color:#14212b}
#trs .tabs button:disabled{opacity:.4}
#trs .tx{font-size:1.06rem;line-height:1.65;padding:10px 12px;background:#fffdf5;border:1px solid #ffe082;border-radius:12px}
#trs .tx[lang=hi]{font-family:"Noto Sans Devanagari",system-ui,sans-serif;font-size:1.1rem}
#trs .tx .bt{display:block;margin-bottom:4px}
#trs .ft{font-size:.78rem;opacity:.75;margin:8px 2px 0}
html.trsopen{overflow:hidden}
html[data-theme=dark] #trs .tx{background:#1d2a33;border-color:#5d4a14}
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