/* ENGINE v1.0 — ATALAKOU; stylesheet shared by both math renderers. */
:root{--blue:#2d5687;--navy:#1e3a5d;--light:#e8f0f9;--orange:#b7470d;--orange-bg:#fff4ed;--ink:#1e293b;--muted:#475569;--line:#ced9e5;--bg:#f6f8fb;--green:#166534;--red:#991b1b;--radius:14px}
*{box-sizing:border-box}html{font-size:16px;scroll-padding-top:150px}body{margin:0;background:var(--bg);color:var(--ink);font:17px/1.65 system-ui,-apple-system,"Segoe UI",Arial,sans-serif;-webkit-text-size-adjust:100%}button,input,select,textarea{font:inherit;color:inherit}button,summary,input,select,textarea{font-size:16px}button,a,summary,input,select{touch-action:manipulation}button,summary{cursor:pointer}button{min-height:44px;border:1px solid var(--line);border-radius:9px;background:#fff;padding:9px 15px;font-weight:650}button:hover{border-color:var(--blue);background:var(--light)}button:disabled{cursor:default;opacity:.7}button:focus-visible,a:focus-visible,summary:focus-visible,input:focus-visible,select:focus-visible,textarea:focus-visible{outline:3px solid #c2410c;outline-offset:3px}a{color:var(--blue);text-underline-offset:3px}h1,h2,h3,h4{line-height:1.3;color:var(--navy)}h2{font-size:1.55rem;margin:0 0 15px}h3{font-size:1.2rem;margin:0 0 12px}h4{font-size:1.05rem;margin:14px 0 8px}p{margin:10px 0}ul,ol{padding-left:24px}li{margin:6px 0}strong{font-weight:720}[hidden]{display:none!important}.sr-only{position:absolute!important;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}.skip{position:absolute;top:-100px;left:10px;background:#fff;padding:12px;z-index:99}.skip:focus{top:10px}.hero{background:var(--navy);color:#fff;border-bottom:5px solid #e8884b}.hero-inner{max-width:1000px;margin:auto;padding:30px 24px 32px}.eyebrow{font-size:16px;font-weight:750;letter-spacing:.13em;color:#dae8fa}.level{font-size:16px;color:#e6eef9;margin:10px 0}.hero h1{color:#fff;font-size:2.45rem;letter-spacing:-.025em;margin:14px 0}.tagline{color:#edf3fb}.pilot-label{display:inline-block;border:1px solid #92afce;border-radius:8px;font-size:16px;padding:5px 12px;margin-top:12px}.tabs{position:sticky;top:0;z-index:20;background:#fff;border-bottom:1px solid var(--line);box-shadow:0 2px 8px #1e3a5d0b}.tabs [role=tablist]{max-width:1000px;margin:auto;display:flex;gap:5px;padding:10px 16px}.tabs button{flex:1;background:transparent;border-color:transparent;color:var(--muted);padding:10px 8px;white-space:nowrap}.tabs button[aria-selected=true]{background:var(--light);color:var(--navy);border-color:#bdd0e5;box-shadow:inset 0 -3px var(--blue)}main{max-width:1000px;padding:24px;margin:auto;min-height:55vh}.panel{min-width:0}.section-intro{margin-bottom:22px}.section-intro p{max-width:760px;color:var(--muted)}.kicker{font-weight:750;color:var(--orange);font-size:16px;letter-spacing:.04em;margin:0 0 8px}.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:24px;margin:0 0 20px;box-shadow:0 3px 14px #1e3a5d04;min-width:0}.card.tight{padding:18px}.grid-two{display:grid;grid-template-columns:1fr 1fr;gap:18px}.grid-two>.card{margin:0}.route{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin:20px 0}.route button{text-align:left;padding:16px;background:#fff;border:1px solid var(--line)}.route strong{display:block;color:var(--navy)}.route span{display:block;font-weight:400;font-size:16px;color:var(--muted)}.box{padding:15px 18px;border-radius:9px;margin:16px 0;border-left:4px solid var(--blue);background:var(--light)}.box strong:first-child{display:block}.box.pitfall{background:var(--orange-bg);border-color:var(--orange)}.box.note{background:#f1f5f9;border-color:#64748b}.worked{padding:16px 18px;border:1px dashed #9fb2c9;border-radius:10px;margin:18px 0;background:#fafcfe}.formula{background:#f1f5f9;border-radius:8px;padding:12px 14px;margin:14px 0;line-height:2}.math{display:inline-block;max-width:100%;vertical-align:baseline}.katex{font-size:1.05em}.katex-display{margin:.4em 0}.katex .katex-mathml{user-select:none}html[data-math=mathml] math{font-size:1.1em}html[data-math=mathml] .katex{font-family:inherit}.math .katex-html{white-space:normal}.figure,figure{margin:18px 0}.figure svg,figure svg,#parabola svg{display:block;width:100%;max-width:500px;height:auto;margin:0 auto}.figure svg text,figure svg text,#parabola svg text{font:20px system-ui,sans-serif;fill:#334155}figcaption{color:var(--muted);font-size:16px;margin-top:8px}.graph-triptych{display:grid;grid-template-columns:1fr;gap:16px}.graph-triptych figure{margin:0;border:1px solid var(--line);padding:12px;border-radius:9px}.sign-table{border-collapse:collapse;width:100%;max-width:520px;margin:18px auto;font-size:16px}.sign-table caption{text-align:left;font-weight:700;padding:6px 0}.sign-table th,.sign-table td{padding:8px 12px;border:1px solid var(--line)}.sign-table th{background:var(--light);text-align:left}.sign-table td:last-child{width:25%;text-align:center;font-weight:750}.prompt{font-weight:650;color:var(--blue)}details{border:1px solid var(--line);border-radius:10px;background:#fff;margin:12px 0}summary{min-height:48px;padding:12px 15px;color:var(--navy);font-weight:700;line-height:1.45}summary::marker{color:var(--orange)}.detail-body{padding:0 16px 18px}details[open]>summary{border-bottom:1px solid var(--line);margin-bottom:14px}details.task>summary .meta{display:block;color:var(--muted);font-weight:400;font-size:16px;margin:5px 0 0 18px}.task{margin:14px 0}.task-body{padding:0 20px 20px}.task-body .correction{background:#fbfcfe}.task-body .correction .detail-body{padding-top:2px}.question{border:1px solid var(--line);border-radius:10px;padding:20px;margin:18px 0}.question h3{font-size:1.1rem}.choices{display:grid;gap:9px;margin:15px 0}.choice{text-align:left;font-weight:400;display:flex;align-items:flex-start;gap:10px;width:100%;min-height:48px;background:#f8fafc}.choice .letter{color:var(--blue);font-weight:750;flex:0 0 20px}.choice.selected{border:2px solid var(--blue);background:var(--light)}.answer-row{display:flex;gap:8px;flex-wrap:wrap;align-items:center;margin:12px 0}.answer-row label{flex:0 0 100%}.answer-row input{min-height:46px;padding:10px;border:1px solid #8195ac;border-radius:8px;min-width:0;flex:1;width:160px;background:#fff}.primary{background:var(--blue);color:#fff;border-color:var(--blue)}.primary:hover{background:var(--navy);color:#fff}.feedback{border-radius:8px;padding:12px 14px;margin:12px 0;font-size:16px}.feedback.good{color:var(--green);background:#eef8f0;border-left:4px solid var(--green)}.feedback.bad{color:var(--red);background:#fff1f1;border-left:4px solid var(--red)}.feedback:empty{display:none}.help-row{display:flex;gap:8px;flex-wrap:wrap;margin:18px 0 10px}.help-row button{font-size:16px}.hint{background:var(--orange-bg);padding:12px 15px;border-left:3px solid var(--orange);margin:8px 0}.state{display:block;font-size:16px;color:var(--muted);margin:10px 0}.state[data-state=autonomous]{color:var(--green)}.state[data-state=aided]{color:#854d0e}.self-grid{border-top:1px solid var(--line);padding-top:14px;margin-top:16px}.check-label{display:flex;gap:10px;align-items:flex-start;min-height:44px;padding:8px 0;font-size:16px}.check-label input{width:22px;height:22px;flex:0 0 22px;margin:3px 0;accent-color:var(--blue)}.self-action{margin:10px 0}.muted{color:var(--muted);font-size:16px}.method-picker label{display:block;margin:15px 0 8px}.method-picker select,select{display:block;width:100%;min-height:46px;border:1px solid #8195ac;border-radius:8px;background:#fff;padding:8px;max-width:100%}.rubric{padding-left:22px;font-size:16px;color:var(--muted)}.rubric li{margin:4px 0}.duty-head{background:#eef3f9;border-radius:10px;padding:20px;margin-bottom:18px}.timer{display:flex;gap:10px;align-items:center;flex-wrap:wrap;margin:14px 0}.clock{font-size:1.25rem;font-weight:700;font-variant-numeric:tabular-nums;padding:6px 12px;background:#fff;border-radius:8px}.progress-list{list-style:none;padding:0;margin:10px 0}.progress-list li{padding:13px 0;border-bottom:1px solid var(--line)}.progress-list li:last-child{border:0}.progress-list strong{display:block}.progress-list span{font-size:16px;color:var(--muted)}.bilan-list li{margin-bottom:12px}.controls{display:grid;gap:12px}.controls label{display:block;font-weight:650}.controls input[type=range]{display:block;width:100%;height:44px;margin:0;accent-color:var(--blue)}output{font-weight:750}.animation-result{background:var(--light);padding:14px;border-radius:8px}.animation-result p{margin:5px 0}textarea{display:block;width:100%;min-height:110px;border:1px solid #8195ac;border-radius:8px;padding:10px}.survey-row{margin:18px 0}.survey-row label{display:block;font-weight:650;margin-bottom:8px}.survey-row select{font-weight:400}.survey-actions{display:flex;gap:10px;flex-wrap:wrap}.copy-area{margin-top:15px}.copy-area textarea{min-height:200px}.storage-message{background:#fff4ed;border:1px solid #d99c78;border-radius:8px;padding:12px;margin-bottom:16px;font-size:16px}footer{max-width:1000px;margin:20px auto;padding:20px 24px 35px;border-top:1px solid var(--line);font-size:16px;color:var(--muted)}footer a{display:inline-block;min-height:44px;padding:10px 0}.memo-grid{display:grid;grid-template-columns:1fr 1fr;gap:16px}.memo-grid section{border:1px solid var(--line);border-radius:8px;padding:16px}.memo-grid h3{font-size:1.05rem}.memo-sub,.memo-foot{color:var(--muted);font-size:16px}.actions{display:flex;flex-wrap:wrap;gap:10px;margin-top:16px}.small-nav{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:20px}.small-nav a{display:inline-flex;align-items:center;min-height:44px;border:1px solid var(--line);border-radius:8px;background:#fff;padding:7px 12px;text-decoration:none;font-size:16px}section[id],article[id]{scroll-margin-top:145px}
@media(min-width:850px){.controls{grid-template-columns:repeat(3,1fr)}.graph-triptych{grid-template-columns:1fr}.graph-triptych figure{display:grid;grid-template-columns:1fr 1fr;align-items:center;gap:20px}.tabs button{font-size:17px}}
@media(max-width:600px){.hero-inner{padding:24px 20px}.hero h1{font-size:1.8rem}.wide-only{display:none}.tabs [role=tablist]{display:grid;grid-template-columns:repeat(6,1fr);gap:4px;padding:7px 10px}.tabs button{grid-column:span 2;font-size:16px;padding:8px 4px;min-width:0}.tabs button:nth-child(4),.tabs button:nth-child(5){grid-column:span 3}main{padding:20px 14px}.card{padding:18px 15px}.question{padding:16px 12px}.task-body{padding:0 12px 16px}.detail-body{padding:0 12px 14px}.route{grid-template-columns:1fr}.grid-two,.memo-grid{grid-template-columns:1fr}.worked{padding:13px 12px}.box{padding:12px}.formula{padding:10px;line-height:2.2}.math{font-size:16px}.katex{font-size:1em}.hero p br{display:none}h2{font-size:1.4rem}.duty-head{padding:16px 12px}.figure svg text,figure svg text,#parabola svg text{font-size:24px}.animation-result{padding:12px}.help-row{gap:6px}.help-row button{flex:1;padding:9px 7px}.task .math{font-size:16px}.self-grid button{width:100%}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important}}
@media print{@page{size:A4;margin:12mm}body{background:#fff;font-size:11pt;line-height:1.4}body>header,body>nav,body>main,body>footer,body>.skip,body>#announcer{display:none!important}#print-memo{display:block!important}#print-memo h2{font-size:20pt;margin-bottom:5mm}#print-memo h3{font-size:12pt;margin:0 0 2mm}#print-memo .memo-grid{display:grid;grid-template-columns:1fr 1fr;gap:4mm}#print-memo .memo-grid section{padding:4mm;break-inside:avoid}#print-memo p{margin:2mm 0}#print-memo .math{font-size:11pt}#print-memo .memo-sub,#print-memo .memo-foot{font-size:10pt}#print-memo .memo-foot{margin-top:5mm}}