.lesson-main{max-width:1180px;padding-top:48px}
.lesson-main [hidden]{display:none!important}
.lesson-intro{max-width:850px;margin-bottom:28px}
.lesson-intro h1{font-size:clamp(34px,5.5vw,66px);line-height:1.06;letter-spacing:-.045em;text-wrap:balance;margin:12px 0 22px}
.lesson-intro>p{max-width:720px;line-height:1.7;color:var(--b-muted)}
.lesson-route-note{font-size:13px}
.lesson-progress{padding:16px 20px;border:1px solid var(--b-line);border-radius:12px;background:var(--b-panel);font-size:14px;line-height:1.6;font-variant-numeric:tabular-nums}
.lesson-progress strong{color:var(--b-text)}
.lesson-progress small{display:block;color:var(--b-muted)}
.lesson-resume,.lesson-sync-status{margin:14px 0;padding:16px 20px;border:1px solid var(--b-line);border-radius:12px;line-height:1.6;font-size:14px;background:var(--b-panel)}
.lesson-resume p,.lesson-sync-status p{margin:4px 0 12px}
.lesson-card .lesson-history{margin-top:10px;background:transparent;color:var(--b-text);font-size:13px}
.lesson-history-list{font-size:13px;line-height:1.6;border-top:1px solid var(--b-line);padding-top:8px}
.lesson-history-list summary{cursor:pointer;min-height:44px;padding:10px 0;color:var(--b-muted)}
.lesson-status{margin:12px 0}
.lesson-status:empty{min-height:0;margin:0}
.lesson-library-heading{display:flex;align-items:end;justify-content:space-between;gap:24px;margin:36px 0 0}
.lesson-library-heading h2{font-size:28px;margin:0}
.lesson-level-filter{display:grid;gap:8px;font-size:13px;color:var(--b-muted);min-width:230px}
.lesson-main select,.lesson-number{background:var(--b-panel);color:var(--b-text);border:1px solid var(--b-control);border-radius:10px;min-height:48px;padding:12px;font:inherit;max-width:100%}
.lesson-count{font-size:13px;color:var(--b-muted);margin-bottom:26px}
.lesson-main h2,.lesson-main h3,.lesson-reader{scroll-margin-top:120px}
.lesson-main h3{margin-top:30px;font-size:20px}
.lesson-model-note{font-size:14px;line-height:1.6;color:var(--b-muted);max-width:800px}
.lesson-grid{grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}
.lesson-card{display:flex;flex-direction:column;gap:12px;min-width:0;padding:24px}
.lesson-card h4{font-size:21px;line-height:1.3;margin:0;text-wrap:balance}
.lesson-card p{font-size:14px;line-height:1.6;margin:0}
.lesson-card .lesson-card-action{margin-top:auto;padding-top:8px}
.lesson-card a.lesson-card-action{min-height:44px;display:flex;align-items:center}
.lesson-card .lesson-card-progress{font-size:12px;color:var(--b-gold)}
.lesson-card button{width:100%;text-align:left}
.lesson-main button,.lesson-main a{touch-action:manipulation}
.lesson-main button{transition:transform 160ms ease,opacity 160ms ease}
.lesson-main button:active:not(:disabled){transform:translateY(1px)}
.lesson-main button:disabled{opacity:.65;cursor:wait}
.lesson-reader{max-width:none;padding:30px;margin:28px 0 36px;animation:lesson-reveal 180ms ease-out}
.lesson-reader-top,.lesson-reader-actions{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap}
.lesson-reader-top .lesson-back,.lesson-reader-actions .lesson-secondary{background:transparent;color:var(--b-text)}
.lesson-reader .lesson-case-number{font-size:13px;color:var(--b-muted);font-variant-numeric:tabular-nums}
.lesson-reader h2{font-size:clamp(25px,3.5vw,36px);margin:28px 0 12px;line-height:1.2}
.lesson-reader .lesson-scenario{font-size:16px;line-height:1.75;max-width:850px;white-space:pre-line}
.lesson-reader .lesson-assumptions{max-width:850px;padding:12px 16px;border-left:2px solid var(--b-line);font-size:13px;line-height:1.65;color:var(--b-muted)}
.lesson-reader legend{font-weight:700;font-size:18px;line-height:1.5;margin-bottom:12px;max-width:850px}
.lesson-reader label{max-width:850px;cursor:pointer;align-items:flex-start;line-height:1.6}
.lesson-reader label:has(input:checked){border-color:var(--b-gold);background:color-mix(in srgb,var(--b-gold) 8%,var(--b-panel))}
.lesson-reader input[type=radio]{margin-top:6px;flex-shrink:0;accent-color:var(--b-gold);width:18px;height:18px}
.lesson-reader .lesson-number-label{display:block;border:0;padding:0;margin-top:8px}
.lesson-number{display:block;width:280px;font-variant-numeric:tabular-nums;margin-top:8px}
.lesson-reader .lesson-field-hint{font-size:13px;color:var(--b-muted)}
.decision-reader{overflow-wrap:anywhere}.decision-reader h1{font-size:clamp(28px,4vw,42px)}.decision-context,.decision-limits{margin:20px 0;line-height:1.65}.decision-context summary,.decision-limits summary{min-height:44px;padding:10px 0;cursor:pointer;font-weight:700}.decision-context dl{display:grid;grid-template-columns:minmax(120px,1fr) 2fr;gap:8px 16px;max-width:850px}.decision-context dd{margin:0}.decision-privacy{font-size:13px;color:var(--b-muted);max-width:850px}.decision-reader fieldset{border:0;padding:0;margin:24px 0}.decision-reader .lesson-sync-status button{margin:8px 8px 0 0;min-height:44px}
.lesson-answer-error{color:var(--b-text);font-weight:700;border-left:3px solid var(--b-gold);padding-left:12px}
.lesson-answer-error:empty{display:none}
.lesson-feedback{padding:20px 24px;background:color-mix(in srgb,var(--b-gold) 5%,var(--b-panel));line-height:1.75;margin-top:28px}
.lesson-feedback h3{margin-top:0}
.lesson-feedback h4{font-size:14px;text-transform:uppercase;letter-spacing:.06em;margin:20px 0 8px}
.lesson-feedback p{max-width:850px;white-space:pre-line;margin:10px 0}
.lesson-feedback .lesson-result{font-size:19px;font-weight:700}
.lesson-feedback small,.lesson-session-note{display:block;color:var(--b-muted);font-size:13px;margin:12px 0}
.lesson-reader-actions{justify-content:flex-start;margin-top:22px}
.lesson-help{margin:38px 0 20px;font-size:14px}
.lesson-archives{border-top:1px solid var(--b-line);padding:20px 0;line-height:1.7;font-size:14px;color:var(--b-muted)}
.lesson-archives summary{font-weight:700;color:var(--b-text);cursor:pointer;min-height:44px;display:list-item;padding:8px 0}
.lesson-archives ul{padding-left:22px}
.lesson-archives li{padding:7px 0}
@keyframes lesson-reveal{from{opacity:0}to{opacity:1}}
@media(hover:hover){.lesson-main button:hover:not(:disabled){opacity:.88}.lesson-card:focus-within{border-color:var(--b-gold)}}
@media(max-width:1000px){.lesson-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:640px){.lesson-main{padding:26px 16px 50px}.lesson-grid{grid-template-columns:1fr}.lesson-library-heading{display:block}.lesson-level-filter{margin-top:20px}.lesson-card{padding:20px}.lesson-reader{padding:20px 16px}.lesson-reader-top{align-items:flex-start}.lesson-feedback{padding:16px}.lesson-reader-actions button{width:100%;text-align:center}.lesson-main h2,.lesson-main h3,.lesson-reader{scroll-margin-top:100px}}
@media(prefers-reduced-motion:reduce){.lesson-main *{animation:none!important;transition:none!important;scroll-behavior:auto!important}.lesson-main button:active:not(:disabled){transform:none}}