:root{color-scheme:light;--paper: #fff8ee;--paper-2: #fdf1e0;--paper-3: #f8e7cf;--card: #ffffff;--ink: #2a2140;--ink-2: #5d5672;--ink-3: #8f88a3;--line: #eadfce;--line-2: #f3ebdf;--brand: #f2762e;--brand-strong: #d45a12;--brand-soft: #ffe9d8;--sun: #ffc23d;--sun-soft: #fff1c9;--good: #189a5f;--good-strong: #0f7a49;--good-soft: #e1f6eb;--bad: #e2554f;--bad-soft: #fdeceb;--warn: #b26b00;--warn-soft: #fff3d6;--strand: #5b5bd6;--strand-soft: #ececfd;--radius-xl: 32px;--radius-lg: 26px;--radius: 18px;--radius-sm: 12px;--shadow-card: 0 1px 0 rgba(42, 33, 64, .04), 0 14px 34px -16px rgba(42, 33, 64, .22);--shadow-pop: 0 24px 60px -16px rgba(42, 33, 64, .4);--font: ui-rounded, "SF Pro Rounded", "Nunito", "Varela Round", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;--calc-cell: 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0;font-size:1.05rem;max-width:45%;line-height:1.15;text-align:right}.input-warn{box-shadow:inset 0 0 0 3px #f0b545,0 0 0 6px var(--warn-soft);animation:shake .4s ease}.input-wrong{background:var(--bad-soft);box-shadow:inset 0 0 0 3px var(--bad)}.input-right{background:var(--good-soft);box-shadow:inset 0 0 0 3px var(--good)}.field-hint{color:var(--ink-3);font-size:.92rem;text-align:center}.field-note{position:relative;padding:10px 14px;border-radius:14px;background:var(--warn-soft);color:#7a4a00;font-weight:700;font-size:1rem;text-align:center;animation:rise .2s ease both}.check-btn{width:min(100%,380px)}.choices{display:grid;grid-template-columns:repeat(var(--cols, 2),minmax(0,1fr));gap:14px;width:100%}.choices.cols-1{--cols: 1}.choices.cols-2{--cols: 2}.choices.cols-3{--cols: 3}.choices.cols-4{--cols: 4}.choice{position:relative;display:flex;align-items:center;gap:14px;min-height:76px;padding:14px 18px;border:0;border-radius:20px;background:#fff;box-shadow:inset 0 0 0 3px var(--line),0 4px 0 var(--line);font-size:1.4rem;font-weight:700;text-align:left;line-height:1.35;transition:transform .08s ease,box-shadow .12s ease,background-color .12s ease,opacity .2s ease}.choice:not(:disabled):active{transform:translateY(3px);box-shadow:inset 0 0 0 3px var(--line),0 1px 0 var(--line)}.choice:disabled{cursor:default}.cols-3 .choice,.cols-4 .choice{justify-content:center;text-align:center}.choice-letter{display:grid;place-items:center;width:38px;height:38px;flex:none;border-radius:12px;background:var(--paper-2);color:var(--ink-2);font-size:1.05rem;font-weight:900}.cols-4 .choice-letter,.cols-3 .choice-letter{position:absolute;top:8px;left:8px;width:28px;height:28px;border-radius:9px;font-size:.85rem}.choice-body{min-width:0}.choice.is-selected{background:var(--brand-soft);box-shadow:inset 0 0 0 3px var(--brand),0 4px 0 var(--brand)}.choice.is-selected .choice-letter{background:var(--brand);color:#fff}.choice.is-correct{background:var(--good-soft);box-shadow:inset 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var(--line)}.steps h3{margin-bottom:14px;font-size:.9rem;color:var(--ink-3);text-transform:uppercase;letter-spacing:.09em;font-weight:900}.steps ol{list-style:none;margin:0;padding:0;counter-reset:step}.steps li{position:relative;padding-left:46px;margin-bottom:16px;font-size:1.2rem;line-height:1.6;counter-increment:step}.steps li:before{content:counter(step);position:absolute;left:0;top:.15em;display:grid;place-items:center;width:30px;height:30px;border-radius:10px;background:var(--strand-soft);color:var(--strand);font-size:.95rem;font-weight:900}.plain-list{margin:8px 0 0;padding-left:1.1em}.plain-list li{counter-increment:none;padding-left:0;margin-bottom:6px;font-size:1em}.plain-list li:before{content:none}.oo-kind{color:var(--ink-2);font-weight:800}.result-actions{display:flex;justify-content:center;margin-top:22px}.result-actions .btn{width:min(100%,380px)}.calc{display:inline-flex;flex-direction:column;font-size:1.5rem;font-weight:700;font-variant-numeric:tabular-nums;line-height:1;padding:6px 4px}.calc-row{display:flex;align-items:center;gap:18px}.calc-cells{display:grid}.calc-cell{height:1.55em;display:grid;place-items:center}.calc-top{border-top:3px solid var(--ink)}.calc-strong .calc-cell,.calc-cell.calc-strong{color:var(--strand);font-weight:900}.calc-muted{color:var(--ink-3)}.calc-accent{color:var(--brand-strong);background:var(--brand-soft);border-radius:6px}.calc-note{font-size:.62em;color:var(--ink-3);font-weight:700}.longdiv{display:inline-flex;align-items:flex-start;font-size:1.5rem}.longdiv-divisor{margin-top:calc(1.55em + 6px);height:1.55em;display:grid;place-items:center;padding:0 10px 0 4px;font-weight:800;font-variant-numeric:tabular-nums;border-right:3px solid var(--ink);border-top-right-radius:14px 100%;border-bottom-right-radius:14px 100%;line-height:1}.longdiv 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td:last-child{border-right:0}.ratio-table th{text-align:left;font-size:1.05rem;background:var(--strand-soft);color:var(--ink);font-weight:800}.ratio-table td{background:#fff;font-weight:800;min-width:70px}.ratio-table td.missing{background:var(--brand-soft);color:var(--brand-strong);font-weight:900}.price-list{display:flex;flex-direction:column;gap:10px;max-width:520px;margin:0 auto;font-size:1.3rem;font-weight:700}.price-row{display:flex;align-items:baseline;gap:10px}.price-dots{flex:1;border-bottom:3px dotted var(--line)}.stemleaf{width:max-content;margin:0 auto;font-variant-numeric:tabular-nums}.stemleaf-title{text-align:center;font-weight:800;color:var(--ink-2);margin-bottom:8px}.stemleaf table{border-collapse:collapse;font-size:1.45rem;font-weight:800}.stemleaf th{font-size:.95rem;color:var(--ink-3);padding:4px 14px;text-transform:uppercase;letter-spacing:.06em}.stemleaf td{padding:5px 16px}.stemleaf td.stem{text-align:right;border-right:3px solid 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