/* GoMaths — Bleu energie. Couleurs uniquement, aucun changement aux exercices. */
:root{--ink:#142e56;--ink-2:#274a78;--paper:#f4f9ff;--blue:#155de0;--orange:#c64324;--yellow:#ffd04c;--green:#087957;--violet:#7045dc;--red:#b72e4b;--muted:#506582;--line:#d2e3fa;--shadow:0 22px 60px rgba(23,85,172,.13)}
body{background:radial-gradient(ellipse 65% 520px at 95% 5%,#cff4ff,transparent),radial-gradient(ellipse 60% 460px at 0 0,#e3ebff,transparent),var(--paper)}
.noise{display:none}
.site-header{background:rgba(255,255,255,.96);border-color:#dce9fa;box-shadow:0 10px 35px rgba(32,87,164,.09)}
.brand{color:#163c86}
.brand-mark{display:flex;align-items:center;justify-content:center;flex-shrink:0;gap:0;padding:0;letter-spacing:-2px;line-height:1;background:linear-gradient(140deg,#1767e8,#2448c7);box-shadow:0 5px 13px rgba(25,91,211,.22)}
.brand-mark span{color:var(--yellow);align-self:center}
.nav-link{color:#23456f}.nav-link:hover{background:#e7f1ff;color:#174ab1}
.nav-link.active{background:#1559cf;color:#fff;box-shadow:0 4px 12px rgba(21,89,207,.16)}
.menu-button,.eyebrow,.text-button,.back-button{color:#1756bd}
.hero h1 span{color:#1556d2;isolation:isolate}
.hero h1 span:after{background:#ffd04c;bottom:1px;height:9px}
.hero-demo:before{background:linear-gradient(145deg,#2866f4 6%,#188bf1 57%,#54dced);box-shadow:0 22px 60px rgba(20,108,230,.22)}
.demo-card{border:1px solid #d7e7fc;box-shadow:0 25px 65px rgba(21,76,160,.2)}
.demo-equation b{color:#165cd8}
.demo-answer{background:#f2f8ff;border-color:#92baf4;color:#42618a}.demo-answer strong{color:#1547a3}
.demo-progress,.progress-track{background:#e5eefb}
.demo-progress span,.progress-track span{background:linear-gradient(90deg,#155de0,#138b84)}
.demo-feedback{background:#def8e9;color:#0c684c}
.badge-a{background:#7548e8;color:#fff}.badge-b{background:#0e8cac;color:#fff}.badge-c{background:#ffd04c;color:#513600}
.pill{background:#e6efff;color:#214fae}
.btn.primary{background:linear-gradient(135deg,#1563e8,#1747c5);color:#fff;box-shadow:0 8px 23px rgba(21,86,205,.24)}
.btn.primary:hover{background:linear-gradient(135deg,#1254d3,#143eaf);box-shadow:0 10px 27px rgba(21,86,205,.29)}
.btn.secondary{background:#fff;color:#164fb7;border-color:#a9c9f6}.btn.secondary:hover{background:#edf5ff;border-color:#7babee}
.btn.light{background:#fff;color:#1648b6}
.category-card{--card-accent:#155de0;--card-tint:#e0edff;--card-mark:#2563eb;--icon-ink:#fff;background:linear-gradient(135deg,#fff 8%,var(--card-tint));color:var(--ink);border-color:#d4e3f6;border-top:4px solid var(--card-mark);box-shadow:0 5px 16px rgba(28,74,145,.05)}
.category-card[data-color="blue"]{--card-accent:#155de0;--card-tint:#dfeeff;--card-mark:#2563eb;border-top-color:var(--card-mark)}
.category-card[data-color="orange"]{--card-accent:#a83d20;--card-tint:#ffe9e0;--card-mark:#ef633b;border-top-color:var(--card-mark)}
.category-card[data-color="violet"]{--card-accent:#6333bd;--card-tint:#ece4ff;--card-mark:#7548e8;border-top-color:var(--card-mark)}
.category-card[data-color="green"]{--card-accent:#087763;--card-tint:#ddf7ed;--card-mark:#0b856b;border-top-color:var(--card-mark)}
.category-card[data-color="yellow"]{--card-accent:#805304;--card-tint:#fff1c6;--card-mark:#ffd04c;--icon-ink:#513600;border-top-color:var(--card-mark)}
.category-card[data-color="red"]{--card-accent:#ad244a;--card-tint:#ffe5ee;--card-mark:#d93769;border-top-color:var(--card-mark)}
.category-icon{width:58px;height:58px;border-radius:17px;display:grid;place-items:center;background:var(--card-mark);color:var(--icon-ink);font-weight:850;box-shadow:0 5px 12px rgba(28,65,127,.12)}
.category-card p{color:#4a607c}
.category-card:after{width:34px;height:34px;display:grid;place-items:center;border-radius:50%;background:#fff;color:var(--card-accent);box-shadow:0 3px 10px rgba(28,74,145,.06)}
.category-card:hover{box-shadow:0 16px 34px rgba(28,74,145,.12)}
.feature-card.dark,.challenge-card{background:linear-gradient(125deg,#1646bc,#116ad4);color:#fff;box-shadow:0 18px 45px rgba(25,83,193,.17)}
.feature-card.dark p,.feature-card.dark .mini-label,.challenge-message{opacity:1;color:#f1f7ff}
.feature-card.paper{background:linear-gradient(135deg,#fff,#ddf3ff);border-color:#c8e0fb}.feature-card.paper p,.feature-card.paper .mini-label{opacity:1;color:#466280}
.filter-button.active{background:#1559cf;color:#fff}.filter-button:not(.active):hover{background:#e4efff;color:#194db1}
.exercise-card{border-color:#d0e1f7;box-shadow:0 4px 14px rgba(21,72,158,.035)}.exercise-card:hover{border-color:#7eaaf0;background:#f7fbff}.exercise-card .symbol{background:#e4efff;color:#1757c9}
.mode-switch{background:#e2edff}.mode-switch button.active{background:#1559cf;color:#fff}
.work-card,.repere-card{background:#fff;border-color:#ccdef7;box-shadow:0 18px 45px rgba(25,83,170,.09)}.equation{color:#184faa}
.answer-row input,.repere-read input{border-color:#9ebfec;background:#fbfdff;color:var(--ink)}.answer-row input:focus,.repere-read input:focus{border-color:#155de0;box-shadow:0 0 0 4px rgba(21,93,224,.14)}
.feedback.good{color:#0b7352}.feedback.bad{color:#b32d46}
.tip-card{background:linear-gradient(135deg,#fff8de,#ffe99d);border:1px solid #efd37b;color:#544015}.tip-card .text-button{color:#71500a}
.work-footer{border-color:#e1edfc}.site-footer{border-color:#ccdef7;color:#506582}
:where(button,a,input,select):focus-visible{outline:3px solid #195ed7;outline-offset:4px}.challenge-card :focus-visible,.feature-card.dark :focus-visible{outline-color:#ffda75}
@media(max-width:900px){.top-nav{background:#fff;border-color:#d3e3fa}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.btn,.category-card,.exercise-card{transition:none}.btn:hover,.category-card:hover,.exercise-card:hover{transform:none}}
@media print{body{background:#fff!important;color:#111}.sheet-preview{background:#fff;color:#111}.sheet-title,.sheet-meta,.sheet-calc{color:#111}}