*{box-sizing:border-box}body{margin:0;background:#f3f6fb;color:#152445;font:16px/1.55 system-ui,sans-serif}button,input,select,textarea{font:inherit}button,a{touch-action:manipulation}button{cursor:pointer;border:0;border-radius:12px;padding:12px 19px;background:#194ce5;color:#fff;font-weight:650}button:hover{filter:brightness(.95)}button:disabled{opacity:.5;cursor:default}button.secondary{background:#e9efff;color:#1943ba}input,select,textarea{width:100%;padding:12px;border:1px solid #c9d3e4;border-radius:10px;background:#fff;color:#152445}textarea{min-height:110px}label{display:block;margin:12px 0 5px}h1{font-size:clamp(28px,4vw,42px);line-height:1.15;letter-spacing:-1px;margin:8px 0 20px}h2{line-height:1.25}p{margin:8px 0 18px}.muted{color:#586880}.shell{display:grid;grid-template-columns:230px 1fr;min-height:100vh}aside{background:#fff;border-right:1px solid #e0e7f2;padding:28px 18px;position:sticky;top:0;height:100vh}.brand{font-size:29px;font-weight:850;color:#194ce5;letter-spacing:-1px;margin-bottom:36px}nav{display:grid;gap:8px}nav button{text-align:left;background:transparent;color:#586880}nav button.active{background:#edf2ff;color:#194ce5}main{padding:30px 5%;max-width:1400px;width:100%;margin:auto}.top{display:flex;justify-content:space-between;align-items:center;gap:12px;margin-bottom:28px}.tag{font-size:13px;font-weight:700;background:#e9efff;color:#1943ba;border-radius:30px;padding:6px 12px;display:inline-block}.hero{background:#142e76;color:#fff;border-radius:24px;display:grid;grid-template-columns:1fr 220px;overflow:hidden;margin:24px 0}.hero .copy{padding:30px}.hero img{width:100%;height:280px;object-fit:cover;object-position:top}.hero button{background:#ffbc58;color:#18284b}.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:18px}.card{background:#fff;border:1px solid #e1e7f0;border-radius:18px;padding:24px}.card h3{margin:8px 0}.row{display:flex;align-items:center;gap:12px;flex-wrap:wrap}.spread{justify-content:space-between}.space{margin-top:24px}.progress{height:9px;border-radius:20px;background:#e2e9f6;overflow:hidden;margin:15px 0}.progress span{height:100%;background:#194ce5;display:block}.choice{display:block;width:100%;text-align:left;margin:10px 0;background:#f1f5ff;color:#152445;border:2px solid transparent}.choice.selected{border-color:#194ce5}.feedback{border-left:4px solid #196c55;padding:16px;background:#eaf8f1;border-radius:8px;margin:18px 0}.bubble{background:#eaf0ff;border-radius:16px;padding:16px;margin:12px 0;max-width:85%}.bubble.mine{margin-left:auto;background:#173fbe;color:#fff}.small{font-size:14px}.table-wrap{overflow:auto}table{border-collapse:collapse;width:100%;text-align:left}td,th{padding:14px;border-bottom:1px solid #e4e9f2;white-space:nowrap}a{color:#194ce5}.error{padding:14px;background:#fff0ed;color:#972f20;border-radius:10px}.success{color:#196c55}.stat{font-size:35px;font-weight:800}.steps{display:flex;gap:8px;flex-wrap:wrap}.steps span{padding:6px 12px;background:#e9efff;border-radius:20px;font-size:14px}.lesson{max-width:820px;margin:auto}.footer-note{margin-top:28px;font-size:14px;color:#66748a}details{margin-top:16px}summary{cursor:pointer;color:#194ce5}dialog{border:0;border-radius:20px;max-width:650px;width:95%;padding:28px}dialog::backdrop{background:#10204499}:focus-visible{outline:3px solid #ed940c;outline-offset:3px}@media(max-width:760px){.shell{display:block}aside{position:static;height:auto;padding:15px;border-bottom:1px solid #ddd}.brand{margin:0 0 10px}nav{display:flex;overflow:auto}nav button{white-space:nowrap;padding:9px 12px}main{padding:22px 16px}.hero{grid-template-columns:1fr 115px}.hero .copy{padding:22px}.hero img{height:100%;min-height:260px}.grid{grid-template-columns:1fr}.top{align-items:flex-start}h1{font-size:30px}}@media(prefers-reduced-motion:no-preference){.card,.hero{animation:appear .25s ease-out}@keyframes appear{0%{opacity:.4;transform:translateY(5px)}to{opacity:1;transform:none}}}.rich-lesson{max-width:980px;margin:auto}.lesson-route{display:flex;gap:10px;overflow-x:auto;padding:12px 0}.lesson-route button{min-width:180px}.lesson-route [aria-current=step]{outline:2px solid #2455dc}.lesson-figure{margin:20px 0;background:#edf3fb;border-radius:18px;overflow:hidden}.lesson-figure img{display:block;width:100%}.lesson-figure figcaption{padding:16px;font-size:14px}.concept-section{padding:20px;background:#f3f6fb;border-radius:14px;margin:16px 0}.concept-section summary{cursor:pointer;font-weight:700}.animated-scene{background:#edf3ff;border-radius:18px;padding:22px;margin:22px 0}.scene-turn{animation:scene-appear .35s ease-out;min-height:150px}.scene-turn strong{color:#234bc2}.rich-lesson section{scroll-margin-top:90px}@keyframes scene-appear{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}@media(prefers-reduced-motion:reduce){.scene-turn{animation:none}html{scroll-behavior:auto}}