/* NexoMath V68 · escritura matemática legible en teléfono + solución infográfica */
/* iOS pinta de azul el texto de los botones sin color propio: se hereda el color del texto. */
button{color:inherit}
.choice,.choices>button,.kid-choices>button,.v63-check .choice,.nx-opt{color:#172344}
.choice.ok,.choice.no{color:inherit}

/* Fracciones más claras: barra firme, números con aire, anidadas un poco menores. */
.n62-frac,.frac{display:inline-flex!important;flex-direction:column;align-items:center;vertical-align:middle;white-space:nowrap;line-height:1.08}
.n62-frac>span:first-child{border-bottom:max(1.6px,.075em) solid currentColor!important;padding:0 .2em .1em!important}
.n62-frac>span:last-child{padding:.1em .2em 0!important}
.n62-frac .n62-frac,.frac .frac,.n62-frac .frac,.frac .n62-frac{font-size:.86em!important;margin:.12em .12em}
.mx-f{margin:0 .14em}

/* Ajuste automático: trozos que no se parten + paréntesis que crecen. */
.mf-root{display:inline;max-width:100%}
.mf-c{display:inline-block;white-space:nowrap;vertical-align:middle;max-width:none}
.mf-g{display:inline-flex;align-items:center;white-space:nowrap;vertical-align:middle}
.mf-in{display:inline-flex;align-items:center;flex-wrap:nowrap;white-space:nowrap}
.mf-p{display:inline-block;transform-origin:center;line-height:1;font-weight:400}
.mf-tall>.mf-p{font-weight:300}
.mf-split{display:block}
.mf-split>.mf-prose{display:block;margin-bottom:.35em}
.mf-split>.mf-block{display:block;text-align:center;line-height:1.9}
.mf-on{overflow-wrap:normal;word-break:normal}
.mf-scroll{overflow-x:auto;-webkit-overflow-scrolling:touch;scrollbar-width:thin}
.mf-scroll>.mf-root{display:inline-block;white-space:nowrap;padding-bottom:4px}
.mf-scroll::after{content:"desliza →";display:block;font-size:11px;font-weight:800;color:#7a84a6;text-align:right}
#question.mf-on,#mixedQ.mf-on,#evalQuestion.mf-on{line-height:1.75}
.nx-math.mf-on,.v63-step-math.mf-on,.helper-math.mf-on{line-height:1.9}

/* Bloques del lenguaje M */
.mx{margin:12px 0;padding:12px 10px;border-radius:14px;background:#f7f8ff;border:1px solid #e3e7fb;text-align:center;font-weight:800;font-size:1.12em;color:#1d2650;overflow:hidden}
.mx-line{line-height:2;padding:2px 0}
.mx-line+.mx-line{border-top:1px dashed #dfe3f6}
.mx-b{color:#2f5be0}.mx-o{color:#e08a00}.mx-g{color:#12925a}.mx-r{color:#d63c48}.mx-p{color:#7c3aed}.mx-k{color:#1d2650}
.mx-root{display:inline-flex;align-items:flex-start;white-space:nowrap}
.mx-rs{font-size:1.12em;line-height:1;margin-right:-.05em}
.mx-rad{border-top:max(1.6px,.075em) solid currentColor;padding:0 .12em;margin-top:.12em}
.mx-ri{font-size:.55em;margin-right:-.35em;position:relative;top:.1em}

/* Botones flotantes: más pequeños en teléfono para no tapar respuestas ni flechas. */
@media (max-width:760px){
 .whatsapp-fab{width:46px!important;height:46px!important;min-width:0!important;padding:0!important;right:10px!important;bottom:146px!important;opacity:.92;box-shadow:0 8px 20px rgba(0,0,0,.18)!important}
 .whatsapp-fab .wa-brand{width:24px!important;height:24px!important;flex-basis:24px!important}
 .tool-fab{width:46px!important;height:46px!important;padding:0!important;right:10px!important;bottom:92px!important;border-radius:15px!important;font-size:0!important;opacity:.92}
 .tool-fab::before{font-size:20px!important}
 .nx-nav{padding-right:0}
}

/* ---------- Solución infográfica ---------- */
.s68-lock{overflow:hidden}
.s68-overlay{position:fixed;inset:0;z-index:5000;background:rgba(15,20,45,.55);display:flex;align-items:stretch;justify-content:center;padding:max(10px,env(safe-area-inset-top)) 8px 8px}
.s68-modal{background:#fff;border-radius:20px;width:min(860px,100%);display:flex;flex-direction:column;overflow:hidden;box-shadow:0 30px 80px rgba(0,0,0,.3)}
.s68-bar{display:flex;align-items:center;gap:10px;padding:10px 12px;border-bottom:1px solid #e6e9f5;font-size:15px}
.s68-bar b{flex:1;text-align:center;color:#1d2650}
.s68-close{border:0;background:#f1f3fb;border-radius:12px;width:40px;height:40px;font-size:18px;font-weight:900;color:#1d2650;cursor:pointer}
.s68-scroll{flex:1;overflow:auto;-webkit-overflow-scrolling:touch;padding:10px}
.s68-actions{display:flex;gap:8px;padding:10px;border-top:1px solid #e6e9f5;background:#fafbff}
.s68-actions button{flex:1;min-height:46px;border:0;border-radius:14px;font-weight:900;font-size:15px;cursor:pointer;background:#5b5cf0;color:#fff}
.s68-actions button+button{background:#1d2650}
.s68-sheet{background:#fff;padding:6px;color:#1d2650;font-family:Inter,system-ui,-apple-system,"Segoe UI",sans-serif}
.s68-head{display:flex;justify-content:space-between;align-items:flex-start;gap:10px;background:linear-gradient(135deg,#eaf0ff,#f4ecff);border-radius:16px;padding:14px 14px 12px;margin-bottom:10px;border:1px solid #dfe5fb}
.s68-head h2{margin:0;font-size:20px;line-height:1.15;color:#1b2a6b}
.s68-head p{margin:4px 0 0;font-size:13px;color:#53608a}
.s68-brand{font-weight:900;font-size:14px;white-space:nowrap}.s68-brand b{color:#5b5cf0}
.s68-card{display:flex;gap:10px;background:var(--t);border:1.5px solid color-mix(in srgb,var(--e) 35%,transparent);border-left:5px solid var(--e);border-radius:16px;padding:12px 12px 12px 10px;margin:10px 0}
.s68-num{flex:0 0 30px;height:30px;border-radius:50%;background:var(--e);color:#fff;font-weight:900;display:flex;align-items:center;justify-content:center;font-size:15px;margin-top:2px}
.s68-body{flex:1;min-width:0}
.s68-body h3{margin:2px 0 8px;font-size:16px;line-height:1.25;color:#1d2650}
.s68-body h3 small{color:var(--e);font-size:15px;font-weight:900}
.s68-math{background:#fff;border-radius:12px;padding:8px 10px;font-weight:800;font-size:17px;text-align:center;line-height:1.9;border:1px solid #e6e9f5;overflow:hidden}
.s68-line+.s68-line{border-top:1px dashed #e3e6f3}
.s68-problem{font-size:18px}
.s68-why{margin:8px 2px 0;font-size:14.5px;line-height:1.5;color:#3a4566}
.s68-goal{margin:8px 2px 0;font-size:14px;color:#3a4566}
.s68-res{margin-top:8px;display:flex;flex-direction:column;gap:4px}
.s68-res>span{font-size:12px;font-weight:900;text-transform:uppercase;letter-spacing:.06em;color:var(--e)}
.s68-res .s68-math{background:#fffef5;border-color:color-mix(in srgb,var(--e) 40%,transparent)}
.s68-answer{margin:12px 0 4px;border-radius:18px;padding:14px;background:linear-gradient(135deg,#1e3a8a,#5b5cf0);color:#fff;text-align:center}
.s68-answer>span{font-weight:900;font-size:16px;display:block;margin-bottom:8px}
.s68-answer .s68-math{background:#fff;color:#1d2650;font-size:22px;display:inline-block;min-width:60%}
.s68-answer p{margin:8px 0 0;font-size:13.5px;opacity:.95}
.s68-open{display:inline-flex;align-items:center;gap:6px;margin:10px 0 0;border:0;border-radius:14px;min-height:44px;padding:10px 16px;background:#eef0ff;color:#3f3fd4;font-weight:900;font-size:15px;cursor:pointer}
.s68-open:hover{background:#e2e5ff}
@media print{
 body.s68-printing>*:not(#s68Overlay){display:none!important}
 body.s68-printing .s68-overlay{position:static;background:none;padding:0}
 body.s68-printing .s68-bar,body.s68-printing .s68-actions{display:none}
 .s68-card,.s68-answer{break-inside:avoid}
 .s68-sheet{-webkit-print-color-adjust:exact;print-color-adjust:exact}
}

/* Matrices y determinantes */
.mx-mat{display:inline-flex;align-items:stretch;vertical-align:middle;margin:0 .2em;position:relative;padding:0 .35em}
.mx-mat::before,.mx-mat::after{content:"";position:absolute;top:0;bottom:0;width:.32em;border:max(1.6px,.08em) solid currentColor}
.mx-mat::before{left:0;border-right:0;border-radius:3px 0 0 3px}.mx-mat::after{right:0;border-left:0;border-radius:0 3px 3px 0}
.mx-det::before{border-top:0;border-bottom:0;border-radius:0;width:0}.mx-det::after{border-top:0;border-bottom:0;border-radius:0;width:0}
.mx-mt{display:inline-flex;flex-direction:column;gap:.05em;padding:.15em .1em}
.mx-mr{display:flex;gap:.2em}
.mx-mc{min-width:1.7em;text-align:center;line-height:1.35}
.s68-problem.s68-prose{font-weight:600;font-size:16px;text-align:left;line-height:1.55}
.t68-qt{line-height:1.7}