:root{font-family:system-ui,-apple-system,Segoe UI,sans-serif;color-scheme:dark;--bg:#071629;--ink:#edf9ff;--muted:#b7ceda;--card:#102b40;--border:#355769;--teal:#4ce3c2;--amber:#ffc47b;--danger:#ffb3a8;--field:#092033}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:radial-gradient(ellipse at 80% 0,#153d56 0,transparent 40%),var(--bg);color:var(--ink);line-height:1.5}a{color:var(--teal)}button,input,select{font:inherit}button{cursor:pointer}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid var(--amber);outline-offset:3px}button,.mini,.secondary{border:1px solid var(--border);background:#1c4656;color:var(--ink);padding:10px 14px;border-radius:11px;font-weight:650}.primary{background:linear-gradient(115deg,#25d0a8,#8ff4bd);border:0;color:#07283c;font-weight:900;width:100%;padding:14px;border-radius:13px}.secondary:hover,.mini:hover{border-color:var(--teal)}.topbar{max-width:1200px;margin:auto;padding:18px 20px;display:flex;align-items:center;gap:16px;justify-content:space-between}.logo{text-decoration:none;white-space:nowrap;font-size:19px;color:var(--ink)}.logo span{color:var(--teal)}nav{display:flex;flex-wrap:wrap;gap:15px;font-size:14px}nav a{text-decoration:none;color:var(--ink)}.wrap{max-width:1160px;margin:0 auto;padding:12px 18px 36px}.hero{display:flex;justify-content:space-between;gap:20px;align-items:center;margin:15px 0 26px;padding:30px 36px;border:1px solid var(--border);background:linear-gradient(125deg,#0b3346,#172443);border-radius:24px}.hero h1{font-size:clamp(2.6rem,6vw,4.5rem);line-height:1.04;margin:7px 0 16px;letter-spacing:-.055em}.hero h1 em{font-style:normal;color:var(--teal)}.hero p{max-width:670px}.eyebrow{color:var(--teal);font-size:12px;font-weight:850;letter-spacing:.14em;margin:0}.hero-art{font-size:116px;font-weight:750;color:var(--teal);opacity:.8;display:flex;flex-direction:column;line-height:1}.hero-art small{font-size:14px;color:var(--amber);font-weight:600;white-space:nowrap}.tags,.tools,.links{display:flex;flex-wrap:wrap;gap:10px}.tags span{border:1px solid #447387;border-radius:99px;padding:5px 10px;font-size:12px}.panel{border:1px solid var(--border);border-radius:20px;padding:24px;background:var(--card);box-shadow:0 14px 30px #0002}.panel h2{margin:4px 0 12px;font-size:1.45rem}.panel h3{font-size:1.05rem}.section-header{display:flex;justify-content:space-between;align-items:flex-start;gap:10px}.config{margin-bottom:20px}.settings{display:grid;grid-template-columns:1fr 2fr;gap:14px}.layout{display:grid;grid-template-columns:minmax(0,1.65fr) minmax(270px,1fr);gap:20px}.solver,.tutor{min-width:0}label{display:block;font-weight:700;font-size:14px;margin:8px 0}label input,label select{margin-top:6px}input,select{display:block;width:100%;border:1px solid #5c8195;background:var(--field);color:var(--ink);padding:12px 13px;border-radius:10px;font-weight:520;font-size:16px;min-width:0}#original,#step{font-family:ui-monospace,SFMono-Regular,Consolas,monospace;font-size:17px;letter-spacing:.015em}.quiet{color:var(--muted);font-size:13px}.drawing{margin:19px 0;background:#092539;border:1px solid #3d7483;border-radius:16px;padding:10px;min-height:160px}.drawing svg{width:100%;height:auto;display:block;max-height:240px}.step-trail{margin:14px 0}.step-trail>div{margin:7px 0;border:1px solid #385d68;border-left:3px solid #4ce3c2;border-radius:9px;padding:9px 12px;display:flex;gap:12px;align-items:baseline;overflow-wrap:anywhere}.step-trail small{color:var(--muted);white-space:nowrap}.keyboard{display:flex;flex-wrap:wrap;gap:7px;margin:12px 0}.keyboard button{padding:8px 11px;font-size:16px;border-radius:9px;min-width:38px;background:#204655}.feedback,.nova-message{padding:14px;margin:15px 0;border-radius:12px;border:1px solid #4c7580;background:#15384a;min-height:54px}.feedback[data-kind=ok]{background:#0d4b42;border-color:#3bba97}.feedback[data-kind=wrong]{background:#49302a;border-color:#9e786a}.nova-title{display:flex;align-items:center;gap:14px}.nova-symbol{font-size:42px;color:var(--teal)}.concept{background:#092539;border-radius:12px;padding:12px 14px;margin-top:19px}.concept h3{margin:4px 0}.concept p{margin:0}hr{border:0;border-top:1px solid var(--border);margin:25px 0}.cross{display:block;margin-top:22px}.integrations{margin-top:21px}.links>a{flex:1;min-width:185px;border:1px solid var(--border);padding:12px;border-radius:11px;text-decoration:none}footer{text-align:center;padding:22px;color:var(--muted);font-size:12px}[data-theme=light]{color-scheme:light;--bg:#f3fafb;--ink:#112d42;--muted:#526a78;--card:white;--border:#bed3dc;--field:#f7fafa}[data-theme=light] .hero{background:linear-gradient(110deg,#e6faf3,#e3edf9)}[data-theme=light] .drawing,[data-theme=light] .concept{background:#ecf6f8}[data-theme=light] .step-trail>div,[data-theme=light] .feedback,[data-theme=light] .nova-message{background:#ebf5f7}[data-theme=light] .feedback[data-kind=wrong]{background:#ffe9df}[data-theme=light] .keyboard button,[data-theme=light] button:not(.primary){background:#e8f4f8;color:var(--ink)}[data-theme=light] .hero-art{color:#137a70}[data-theme=light] .hero-art small{color:#986022}
@media(max-width:800px){.topbar{flex-wrap:wrap}.layout{grid-template-columns:1fr}.hero{padding:23px;align-items:start}.hero-art{font-size:70px}.hero-art small{font-size:10px}.panel{padding:18px}.settings{grid-template-columns:1fr}}@media(max-width:460px){.hero-art{display:none}.topbar nav{width:100%;gap:12px}.panel{padding:15px}.wrap{padding-inline:11px}.tools button{flex:1}.step-trail>div{align-items:flex-start}.hero h1{font-size:2.8rem}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{animation:none!important;transition:none!important}}

/* NOVA 7.1 · Indicació visual accessible i alternatives sense respostes automàtiques */
.math-preview{margin:7px 0 14px;border:1px dashed var(--border);background:var(--field);border-radius:10px;padding:10px 14px;overflow-wrap:anywhere}.math-preview small{display:block;color:var(--muted)}.math-preview output{font-size:1.2rem;font-weight:750;letter-spacing:.02em}.choices{margin:12px 0;border:1px solid #66829a;padding:14px;border-radius:12px}.choices[hidden]{display:none}.choices p{margin:0 0 10px;font-weight:680}.choices button{display:block;width:100%;margin:6px 0;text-align:left;font-family:ui-monospace,monospace}.drawing .nova-focus{stroke:#ffd976;stroke-width:5;filter:drop-shadow(0 0 9px #ffbf69)}.drawing .nova-arrow-focus{stroke:#ffb95a;stroke-width:5;stroke-dasharray:9 3}@media(prefers-reduced-motion:no-preference){.drawing .nova-focus{animation:novaFocus 1.6s ease-in-out infinite alternate}@keyframes novaFocus{to{filter:drop-shadow(0 0 2px #ffbf69)}}}

/* NOVA 8.0 · Seguiment formatiu responsive */
.learning-plan{margin:20px 0}.learning-metrics{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:10px;margin:15px 0}.learning-metrics>div{border:1px solid var(--border);background:var(--field);border-radius:12px;padding:14px}.learning-metrics strong{display:block;font-size:clamp(1.3rem,3vw,2rem);color:var(--teal);font-variant-numeric:tabular-nums}.learning-metrics span{display:block;font-size:13px;color:var(--muted)}.recommendations{display:grid;grid-template-columns:repeat(auto-fit,minmax(245px,1fr));gap:10px;margin:10px 0 16px}.recommendation{border:1px solid #578a8b;padding:15px;border-radius:14px;background:var(--field)}.recommendation>strong{font-size:1.06rem;color:var(--teal)}.recommendation p{font-size:.92rem;margin:10px 0}.recommendation button{max-width:100%}.diagnostic-note{border-left:3px solid #e3bb73;background:var(--field);padding:10px 13px;font-size:.92rem;border-radius:5px 10px 10px 5px}.learning-plan .tools{margin-top:14px}@media(max-width:650px){.learning-metrics{grid-template-columns:repeat(2,minmax(0,1fr))}.learning-plan .section-header{display:block}}@media(max-width:370px){.learning-metrics span{font-size:12px}}

.nova29-related{display:grid;gap:9px}.nova29-related-link{display:block;padding:11px 14px;border:1px solid var(--border);border-radius:11px;color:var(--teal);text-decoration:none;font-weight:650}.nova29-related-link:focus-visible{outline:3px solid #e3bb73}