.force-light,.force-light *{color-scheme:light}.force-light{--background:0 0% 100%;--foreground:222.2 84% 4.9%}:root{--bg-primary:#faf8ff;--bg-secondary:#f2f3fe;--bg-card:#fff;--bg-nav:rgba(250,248,255,.8);--accent:#0056d2;--accent-hover:#0047b3;--accent-light:#e8f0fe;--success:#16a34a;--success-light:#dcfce7;--error:#dc2626;--error-light:#fef2f2;--warning:#d97706;--warning-light:#fef9c3;--text-primary:#191b23;--text-secondary:#4b5064;--text-muted:#8b8fa3;--text-on-accent:#fff;--border:#e2e4ef;--border-hover:#c5c8da;--shadow-sm:0 1px 3px 0 rgba(25,27,35,.04);--shadow-md:0 4px 16px 0 rgba(25,27,35,.06);--shadow-lg:0 8px 32px 0 rgba(25,27,35,.06);--radius-sm:8px;--radius-md:12px;--radius-lg:16px;--radius-full:9999px;--font-display:"Lexend",system-ui,sans-serif;--font-body:"Plus Jakarta Sans",system-ui,sans-serif}.card-exercise{background-color:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-md);padding:1.5rem;box-shadow:var(--shadow-sm);transition:border-color .2s ease,box-shadow .2s ease}.card-exercise:hover{border-color:var(--border-hover);box-shadow:var(--shadow-md)}.card-exercise.is-correct{border-color:var(--success);background-color:var(--success-light)}.card-exercise.is-incorrect{border-color:var(--error);background-color:var(--error-light)}.btn-primary{display:inline-flex;align-items:center;justify-content:center;gap:.5rem;padding:.625rem 1.5rem;background-color:var(--accent);color:var(--text-on-accent);font-family:var(--font-body);font-weight:600;font-size:.9375rem;letter-spacing:.01em;border-radius:var(--radius-sm);border:none;cursor:pointer;transition:background-color .18s ease,transform .12s ease,box-shadow .18s ease;-webkit-user-select:none;-moz-user-select:none;user-select:none}.btn-primary:hover{background-color:var(--accent-hover);box-shadow:0 4px 12px rgba(0,86,210,.25)}.btn-primary:active{transform:scale(.97)}.btn-primary:disabled{opacity:.5;cursor:not-allowed;transform:none}.btn-ghost{display:inline-flex;align-items:center;justify-content:center;gap:.5rem;padding:.625rem 1.5rem;background-color:transparent;color:var(--text-primary);font-family:var(--font-body);font-weight:500;font-size:.9375rem;border-radius:var(--radius-sm);border:1px solid var(--border);cursor:pointer;transition:background-color .18s ease,border-color .18s ease}.btn-ghost:hover{border-color:var(--border-hover)}.btn-ghost:hover,.progress-bar{background-color:var(--bg-secondary)}.progress-bar{width:100%;height:6px;border-radius:var(--radius-full);overflow:hidden}.progress-bar__fill{height:100%;background-color:var(--accent);border-radius:var(--radius-full);transition:width .4s cubic-bezier(.4,0,.2,1)}.progress-badge{display:inline-flex;align-items:center;padding:.25rem .75rem;background-color:var(--accent-light);color:var(--accent);font-size:.8125rem;font-weight:600;border-radius:var(--radius-full);letter-spacing:.03em}.feedback-correct{color:var(--success);font-weight:600}.feedback-incorrect{color:var(--error);font-weight:600}.input-exercise{background-color:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-sm);padding:.5rem .875rem;font-family:var(--font-body);font-size:1rem;color:var(--text-primary);outline:none;transition:border-color .18s ease,box-shadow .18s ease;width:100%}.input-exercise:focus{border-color:var(--accent);box-shadow:0 0 0 3px rgba(0,86,210,.12)}.input-exercise.is-correct{border-color:var(--success);box-shadow:0 0 0 3px rgba(22,163,74,.12)}.input-exercise.is-incorrect{border-color:var(--error);box-shadow:0 0 0 3px rgba(220,38,38,.12)}article.prose h3{margin-top:1.75rem;margin-bottom:.75rem;font-size:1.5rem;color:var(--text-primary);font-family:var(--font-display)}article.prose h3:first-child{margin-top:0}article.prose p{margin-bottom:1rem;line-height:1.7;color:var(--text-secondary)}article.prose table{width:100%;border-collapse:separate;border-spacing:0;margin:1rem 0 1.5rem;border-radius:var(--radius-md);overflow-x:auto;-webkit-overflow-scrolling:touch;display:block;border:1px solid var(--border);font-size:.9375rem}article.prose thead th{background-color:var(--accent-light);color:var(--accent);font-weight:700;font-size:.8125rem;text-transform:uppercase;letter-spacing:.06em;padding:.75rem 1rem;text-align:center;border-bottom:2px solid rgba(0,86,210,.15)}article.prose tbody td{padding:.75rem 1rem;border-bottom:1px solid var(--border);vertical-align:middle}article.prose tbody tr:last-child td{border-bottom:none}article.prose tbody tr:hover{background-color:var(--bg-secondary)}article.prose em{color:var(--accent);font-style:normal;font-weight:500}.tl-card{background-color:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-md);padding:1.5rem 1.5rem 1rem;margin:1.5rem auto;text-align:center;max-width:320px;box-shadow:var(--shadow-sm)}.tl-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:1rem;margin:1.5rem 0}.tl-grid .tl-card{max-width:none;margin:0}@media (max-width:600px){article.prose tbody td,article.prose thead th{padding:.5rem .75rem;font-size:.8rem}article.prose thead th{font-size:.7rem}}@media (max-width:500px){.tl-grid{grid-template-columns:1fr}}.tl-icon{display:flex;align-items:center;justify-content:center;width:48px;height:48px;margin:0 auto .5rem;font-size:1.5rem;border-radius:50%;background-color:var(--accent-light);color:var(--accent)}.tl-title{font-family:var(--font-body);font-size:.7rem;font-weight:700;text-transform:uppercase;letter-spacing:.12em;color:var(--text-muted)}.tl-name,.tl-title{margin-bottom:.25rem}.tl-name{font-family:var(--font-display);font-size:1.125rem;font-weight:600;color:var(--text-primary)}.tl-formula{font-size:.8125rem;color:var(--text-muted);margin-bottom:.125rem}.tl-helper{font-size:.875rem;font-weight:600;color:var(--success);margin-top:.75rem}article.prose .tl-example{font-family:var(--font-display);font-style:italic;font-size:.9375rem;color:var(--text-primary);margin-top:.5rem;margin-bottom:0}.tl-timeline{position:relative;margin:1.25rem 0 .25rem;height:74px}.tl-timeline:after{left:0;right:0;bottom:16px;height:2px}.tl-timeline:after,.tl-timeline:before{content:"";position:absolute;background-color:var(--text-primary)}.tl-timeline:before{left:50%;bottom:14px;width:2px;height:10px;transform:translateX(-50%)}.tl-labels{justify-content:space-between;bottom:0;left:0;right:0;font-size:.625rem;text-transform:uppercase;letter-spacing:.06em;color:var(--text-muted)}.tl-labels,.tl-marks{display:flex;position:absolute}.tl-marks{bottom:22px;left:5%;right:5%;justify-content:space-around}.tl-x{position:relative;width:10px;height:10px}.tl-x:after,.tl-x:before{content:"";position:absolute;left:50%;top:50%;width:10px;height:2px;background-color:var(--accent);border-radius:1px}.tl-x:before{transform:translate(-50%,-50%) rotate(45deg)}.tl-x:after{transform:translate(-50%,-50%) rotate(-45deg)}.tl-arc{position:absolute;bottom:18px;left:30%;right:30%;height:28px;border:2px dashed var(--accent);border-bottom:none;border-radius:50% 50% 0 0}.tl-arrow{position:absolute;bottom:23px;left:8%;width:42%;height:2px;background-color:var(--accent)}.tl-arrow:after{content:"";position:absolute;right:-1px;top:50%;transform:translateY(-50%);border-left:6px solid var(--accent);border-top:4px solid transparent;border-bottom:4px solid transparent}.tl-x--end{left:50%;transform:translateX(-50%)}.tl-wave,.tl-x--end{position:absolute;bottom:18px}.tl-wave{left:8%;width:52%;height:18px;background:linear-gradient(90deg,rgba(0,86,210,.3),rgba(0,86,210,.6) 55%,rgba(0,86,210,.1));border-radius:8px 8px 0 0;opacity:.6}.tl-cyclist{position:absolute;bottom:26px;font-size:1.125rem;line-height:1;z-index:1;filter:grayscale(.3);transform:scaleX(-1)}.tl-simple .tl-cyclist{animation:tl-habitual 2.8s linear infinite}@keyframes tl-habitual{0%{left:-5%;opacity:0;transform:scaleX(-1)}8%{left:2%;opacity:1;transform:scaleX(-1)}80%{left:90%;opacity:1;transform:scaleX(-1)}90%{left:95%;opacity:0;transform:scaleX(-1)}to{left:95%;opacity:0;transform:scaleX(-1)}}.tl-continuous .tl-cyclist{left:46%;animation:tl-pedaling .5s ease-in-out infinite alternate}@keyframes tl-pedaling{0%{transform:scaleX(-1) translateY(0) rotate(-3deg)}to{transform:scaleX(-1) translateY(-4px) rotate(3deg)}}.tl-perfect .tl-cyclist{animation:tl-done 3.5s ease-out infinite}@keyframes tl-done{0%{left:2%;opacity:1;transform:scaleX(-1) scale(1)}45%{left:44%;opacity:1;transform:scaleX(-1) scale(1)}55%{left:46%;opacity:1;transform:scaleX(-1) scale(1.15)}to{left:46%;opacity:1;transform:scaleX(-1) scale(1)}}.tl-perf-cont .tl-cyclist{animation:tl-ongoing 3s ease-in-out infinite}@keyframes tl-ongoing{0%{left:2%;transform:translateY(0) rotate(0deg) scaleX(-1)}50%{left:46%;transform:translateY(0) rotate(0deg) scaleX(-1)}57%{left:48%;transform:translateY(-3px) rotate(-2deg) scaleX(-1)}64%{left:50%;transform:translateY(0) rotate(2deg) scaleX(-1)}71%{left:52%;transform:translateY(-3px) rotate(-2deg) scaleX(-1)}78%{left:54%;transform:translateY(0) rotate(2deg) scaleX(-1)}85%{left:56%;transform:translateY(-3px) rotate(-2deg) scaleX(-1)}92%{left:58%;transform:translateY(0) rotate(0deg) scaleX(-1)}to{left:58%;transform:translateY(0) rotate(0deg) scaleX(-1)}}.tl-future-simple .tl-marks{left:58%;right:2%}.tl-future-simple .tl-cyclist{animation:tl-future-simple 3.8s ease-in infinite}@keyframes tl-future-simple{0%{left:48%;opacity:0;transform:scaleX(-1)}10%{left:50%;opacity:1;transform:scaleX(-1)}80%{left:92%;opacity:1;transform:scaleX(-1)}90%{left:95%;opacity:0;transform:scaleX(-1)}to{left:95%;opacity:0;transform:scaleX(-1)}}.tl-future-cont .tl-arc{left:58%;right:10%}.tl-future-cont .tl-cyclist{left:68%;animation:tl-pedaling .5s ease-in-out infinite alternate}.tl-future-perfect-tense .tl-arrow{left:50%;width:34%}.tl-future-perfect-tense .tl-x--end{left:83%;transform:none}.tl-future-perfect-tense .tl-cyclist{animation:tl-future-done 3.5s ease-out infinite}@keyframes tl-future-done{0%{left:50%;opacity:1;transform:scaleX(-1) scale(1)}50%{left:76%;opacity:1;transform:scaleX(-1) scale(1)}65%{left:78%;opacity:1;transform:scaleX(-1) scale(1.15)}to{left:78%;opacity:1;transform:scaleX(-1) scale(1)}}.tl-future-perf-cont .tl-wave{left:50%;width:36%}.tl-future-perf-cont .tl-cyclist{animation:tl-future-perf-cont 3s ease-in-out infinite}@keyframes tl-future-perf-cont{0%{left:50%;transform:translateY(0) rotate(0deg) scaleX(-1)}40%{left:70%;transform:translateY(0) rotate(0deg) scaleX(-1)}48%{left:72%;transform:translateY(-3px) rotate(-2deg) scaleX(-1)}56%{left:74%;transform:translateY(0) rotate(2deg) scaleX(-1)}64%{left:76%;transform:translateY(-3px) rotate(-2deg) scaleX(-1)}72%{left:78%;transform:translateY(0) rotate(0deg) scaleX(-1)}to{left:78%;transform:translateY(0) 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.tl-wave{left:2%;width:36%}.tl-past-perf-cont .tl-cyclist{animation:tl-past-perf-cont 3s ease-in-out infinite}@keyframes tl-past-perf-cont{0%{left:2%;transform:translateY(0) rotate(0deg) scaleX(-1)}40%{left:28%;transform:translateY(0) rotate(0deg) scaleX(-1)}48%{left:30%;transform:translateY(-3px) rotate(-2deg) scaleX(-1)}56%{left:32%;transform:translateY(0) rotate(2deg) scaleX(-1)}64%{left:34%;transform:translateY(-3px) rotate(-2deg) scaleX(-1)}72%{left:36%;transform:translateY(0) rotate(0deg) scaleX(-1)}to{left:36%;transform:translateY(0) rotate(0deg) scaleX(-1)}}