/* NexoMath V68 · «Aprende un tema» + lecciones detalladas de fracciones */
#temas{--t68ink:#1d2650;--t68mut:#5b6787;--t68line:#e3e7f5;--t68p:#5b5cf0;color:var(--t68ink)}
.t68-hero{display:flex;flex-wrap:wrap;gap:14px;justify-content:space-between;align-items:flex-end;background:linear-gradient(135deg,#232a6b,#5b5cf0 70%,#8b5cf6);color:#fff;border-radius:24px;padding:22px 18px;margin-bottom:14px}
.t68-hero .eyebrow{color:#c9d2ff;font-size:12px;letter-spacing:.14em;font-weight:900}
.t68-hero h2{margin:6px 0 6px;font-size:30px;line-height:1.05}
.t68-hero p{margin:0;max-width:640px;line-height:1.5;color:#e6e9ff;font-size:15px}
.t68-grade{display:flex;flex-direction:column;gap:6px;font-weight:900;font-size:12px;text-transform:uppercase;letter-spacing:.08em}
.t68-grade select{min-height:44px;border-radius:12px;border:0;padding:0 12px;font-weight:900;font-size:16px;color:#1d2650;background:#fff}
.t68-search input{width:100%;min-height:48px;border-radius:14px;border:1.5px solid var(--t68line);padding:0 14px;font-size:16px;background:#fff;color:var(--t68ink);box-sizing:border-box}
.t68-areas{display:flex;gap:8px;overflow-x:auto;padding:12px 0 4px;-webkit-overflow-scrolling:touch}
.t68-areas button{flex:0 0 auto;border:1.5px solid var(--t68line);background:#fff;border-radius:999px;padding:9px 14px;font-weight:800;font-size:13px;color:var(--t68ink);cursor:pointer}
.t68-areas button.on{background:var(--t68p);border-color:var(--t68p);color:#fff}
.t68-h{margin:18px 2px 10px;font-size:18px;color:var(--t68ink)}
.t68-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(270px,1fr));gap:10px}
.t68-card{display:flex;gap:12px;text-align:left;background:#fff;border:1.5px solid var(--t68line);border-radius:18px;padding:14px;cursor:pointer;color:var(--t68ink);box-shadow:0 6px 18px rgba(30,40,90,.05);transition:transform .15s,border-color .15s}
.t68-card:hover{transform:translateY(-2px);border-color:#c4c8f7}
.t68-ic{flex:0 0 46px;height:46px;border-radius:14px;background:#f0f1ff;display:flex;align-items:center;justify-content:center;font-size:24px}
.t68-ic.big{flex-basis:58px;height:58px;font-size:30px}
.t68-ct{display:flex;flex-direction:column;gap:3px;min-width:0}
.t68-ct b{font-size:15.5px;line-height:1.25}
.t68-ct small{color:var(--t68p);font-weight:800;font-size:12px}
.t68-cr{color:var(--t68mut);font-size:13px;line-height:1.4;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.t68-mini{display:block;height:6px;border-radius:9px;background:#eceefa;margin-top:6px;overflow:hidden}.t68-mini i{display:block;height:100%;background:#22c55e}
.t68-empty{padding:20px;text-align:center;color:var(--t68mut)}
.t68-banner{display:flex;align-items:center;gap:12px;width:100%;text-align:left;border:0;border-radius:20px;padding:16px;margin:0 0 14px;background:linear-gradient(135deg,#eef0ff,#f6edff);border:1.5px solid #d9dcff;color:#1d2650;cursor:pointer;box-shadow:0 8px 22px rgba(60,60,160,.08)}
.t68-banner>span:first-child{font-size:30px}
.t68-banner span{display:flex;flex-direction:column;gap:3px}.t68-banner b{font-size:16px}.t68-banner small{color:#56618a;font-size:13.5px;line-height:1.4}
.t68-banner>b:last-child{margin-left:auto;font-size:22px;color:#5b5cf0}

.t68-top{display:flex;align-items:center;gap:10px;flex-wrap:wrap;margin-bottom:10px}
.t68-back{border:0;background:#fff;border:1.5px solid var(--t68line);border-radius:12px;min-height:42px;padding:0 14px;font-weight:900;color:var(--t68ink);cursor:pointer}
.t68-dom{display:flex;align-items:center;gap:8px;flex:1;min-width:200px;font-size:12px;font-weight:800;color:var(--t68mut)}
.t68-bar{flex:1;height:10px;border-radius:9px;background:#e9ebf8;overflow:hidden}.t68-bar i{display:block;height:100%;background:linear-gradient(90deg,#22c55e,#16a34a);transition:width .4s}
.t68-dom b{color:#16a34a;font-size:14px}
.t68-head{display:flex;gap:12px;align-items:flex-start;background:#fff;border:1.5px solid var(--t68line);border-radius:20px;padding:16px;margin-bottom:10px}
.t68-head small{color:var(--t68p);font-weight:900;font-size:12px}
.t68-head h2{margin:3px 0 6px;font-size:22px;line-height:1.15}
.t68-head p{margin:0;color:var(--t68mut);line-height:1.5;font-size:14.5px}
.t68-pdfrow{display:flex;flex-wrap:wrap;gap:8px;margin:0 0 10px}
.t68-btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:44px;padding:0 16px;border-radius:14px;border:0;background:var(--t68p,#5b5cf0);color:#fff!important;font-weight:900;font-size:14.5px;text-decoration:none;cursor:pointer}
.t68-btn.ghost{background:#eef0ff;color:#3f3fd4!important}
.t68-btn.good{background:#16a34a}.t68-btn.bad{background:#e5484d}
.t68-tabs{position:sticky;top:0;z-index:20;display:flex;gap:6px;overflow-x:auto;padding:8px 2px;background:rgba(245,246,252,.96);backdrop-filter:blur(8px);-webkit-overflow-scrolling:touch;scrollbar-width:none}
.t68-tabs::-webkit-scrollbar{display:none}
.t68-tabs button{flex:0 0 auto;border:1.5px solid var(--t68line);background:#fff;border-radius:999px;padding:9px 13px;font-weight:900;font-size:13.5px;color:var(--t68ink);cursor:pointer}
.t68-tabs button.on{background:#1d2650;color:#fff;border-color:#1d2650}
.t68-body{padding:4px 0 6px}
.t68-next{display:flex;justify-content:space-between;gap:8px;margin:14px 0 30px}
.t68-goals{background:#f0fdf4;border:1.5px solid #bbf7d0;border-radius:18px;padding:12px 16px;margin:6px 0 12px}
.t68-goals h4{margin:2px 0 6px}.t68-goals ul{margin:0;padding-left:20px;line-height:1.6}
.t68-sec,.t68-ex,.t68-guide{background:#fff;border:1.5px solid var(--t68line);border-radius:20px;padding:16px;margin:0 0 12px;box-shadow:0 6px 18px rgba(30,40,90,.04)}
.t68-sec h3{display:flex;align-items:center;gap:10px;margin:0 0 10px;font-size:18px;line-height:1.25}
.t68-sec h3 span{flex:0 0 30px;height:30px;border-radius:10px;background:var(--t68p,#5b5cf0);color:#fff;display:flex;align-items:center;justify-content:center;font-size:15px}
.t68-sec h5{margin:14px 0 6px;font-size:15.5px;color:#3730a3}
.t68-sec p,.t68-sec li{line-height:1.6;font-size:15.5px}
.t68-list{padding-left:20px}.t68-list li{margin:4px 0}
.t68-steps{padding-left:22px}.t68-steps li{margin:6px 0}
.t68-two{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin:10px 0}
@media(max-width:560px){.t68-two{grid-template-columns:1fr}}
.t68-key{border-radius:16px;padding:12px;border:1.5px solid}.t68-key p{margin:4px 0 0;font-size:14.5px}
.t68-kb{background:#eef4ff;border-color:#bcd0ff}.t68-ko{background:#fff6e8;border-color:#fcd9a0}.t68-kg{background:#ecfdf3;border-color:#a7f3c8}.t68-kr{background:#fff0f1;border-color:#fecdd3}
.t68-key .mx{background:#fff}
.t68-note{background:#fffbea;border:1.5px solid #fde68a;border-radius:14px;padding:10px 12px;margin:10px 0;font-size:14.5px;line-height:1.5}
.t68-vrow{display:flex;flex-wrap:wrap;gap:10px;align-items:center;justify-content:center;margin:10px 0}
.t68-fig{margin:6px auto;display:flex;flex-direction:column;align-items:center;gap:4px;max-width:100%}
.t68-fig svg{max-width:100%;height:auto}
.t68-fig figcaption{font-size:13.5px;color:var(--t68mut);text-align:center;font-weight:700}
.t68-op{font-size:28px;font-weight:900;color:#5b5cf0}
.t68-table-wrap{overflow-x:auto;margin:10px 0}
.t68-table{width:100%;border-collapse:separate;border-spacing:0;border:1.5px solid #f2c94c;border-radius:14px;overflow:hidden;font-size:15px}
.t68-table th{background:#f8d978;color:#3b2f00;padding:8px;font-size:13px}
.t68-table td{background:#fff8de;border-top:1px solid #f4dc8c;padding:6px 8px;text-align:center}
.t68-table td svg{width:56px;height:56px}
.t68-read td:last-child b{color:#d6336c}
.t68-big{font-size:20px;font-weight:900;color:#1d4ed8}
.t68-rules{padding:0;list-style:none;counter-reset:r}
.t68-rules li{counter-increment:r;position:relative;background:#fff;border:1.5px solid var(--t68line);border-radius:16px;padding:12px 12px 12px 50px;margin:8px 0;line-height:1.6;font-size:15.5px}
.t68-rules li::before{content:counter(r);position:absolute;left:12px;top:11px;width:28px;height:28px;border-radius:9px;background:#eef0ff;color:#4338ca;font-weight:900;display:flex;align-items:center;justify-content:center}
.t68-proc{display:flex;flex-direction:column;gap:8px}
.t68-pstep{display:flex;gap:12px;background:#fff;border:1.5px solid var(--t68line);border-radius:16px;padding:12px}
.t68-pstep>i{flex:0 0 32px;height:32px;border-radius:50%;background:#5b5cf0;color:#fff;font-style:normal;font-weight:900;display:flex;align-items:center;justify-content:center}
.t68-pstep p{margin:4px 0;color:var(--t68mut);line-height:1.5}
.t68-pex{background:#f7f8ff;border-radius:10px;padding:6px 10px;font-weight:800;line-height:1.9}
.t68-lead{color:var(--t68mut);margin:4px 2px 10px;line-height:1.5}
.t68-ex header{display:flex;flex-direction:column;gap:2px;margin-bottom:6px}.t68-ex header span{color:#5b5cf0;font-weight:900;font-size:12px;text-transform:uppercase;letter-spacing:.08em}.t68-ex header b{font-size:17px}
.t68-ex .s68-head{display:none}
.t68-viz{display:flex;justify-content:center;margin:6px 0 10px}.t68-viz svg{max-width:100%;height:auto}
.t68-err{display:grid;grid-template-columns:1fr 1fr;gap:8px;margin:8px 0}
@media(max-width:560px){.t68-err{grid-template-columns:1fr}}
.t68-err>div{border-radius:14px;padding:10px 12px;line-height:1.6}.t68-err small{display:block;font-weight:900;margin-bottom:2px}
.t68-err .bad{background:#fff0f1;border:1.5px solid #fecdd3}.t68-err .good{background:#ecfdf3;border:1.5px solid #a7f3c8}
.t68-pinfo{background:#eef0ff;border-radius:14px;padding:10px 12px;font-size:14px;color:#3f3fd4;font-weight:700;margin-bottom:10px}
.t68-q{background:#fff;border:1.5px solid var(--t68line);border-radius:20px;padding:14px;margin-bottom:10px}
.t68-qn{font-size:12px;font-weight:900;color:#5b5cf0;text-transform:uppercase;letter-spacing:.08em;margin-bottom:6px}
.t68-qt{font-size:20px;font-weight:800;line-height:1.7;text-align:center}
.t68-opts{display:grid;grid-template-columns:1fr 1fr;gap:8px}
.t68-opts.small{margin-top:8px}
@media(max-width:420px){.t68-opts{grid-template-columns:1fr}}
.t68-opt{min-height:56px;border:1.5px solid var(--t68line);border-radius:16px;background:#fff;color:#1d2650;font-weight:800;font-size:17px;padding:8px 10px;cursor:pointer;line-height:1.6;text-align:center}
.t68-opt span{display:block}
.t68-opt:hover:not(:disabled){border-color:#a5a8f5;background:#fafaff}
.t68-opt.ok{background:#ecfdf3;border-color:#22c55e}.t68-opt.no{background:#fff0f1;border-color:#e5484d}
.t68-opt:disabled{cursor:default;opacity:1}
.t68-fb{margin-top:10px}
.t68-fbt{border-radius:14px;padding:10px 12px;line-height:1.6;font-size:15px}.t68-fbt.good{background:#ecfdf3}.t68-fbt.bad{background:#fff0f1}
.t68-mini-steps{padding-left:20px;margin:10px 0}.t68-mini-steps li{margin:8px 0}.t68-mini-steps p{margin:2px 0;color:var(--t68mut);font-size:14px;line-height:1.5}
.t68-sm{background:#f7f8ff;border-radius:10px;padding:4px 8px;font-weight:800;line-height:1.9;margin-top:3px}
.t68-fbb{display:flex;flex-wrap:wrap;gap:8px;align-items:center;justify-content:space-between}
.t68-rq{background:#fff;border:1.5px solid var(--t68line);border-radius:18px;padding:12px;margin:0 0 10px}
.t68-rq>b{display:block;line-height:1.55;font-size:15.5px}
.t68-why{margin-top:8px;line-height:1.5;font-size:14.5px;color:#334155}
.t68-games{display:grid;grid-template-columns:repeat(auto-fill,minmax(160px,1fr));gap:8px;margin-bottom:12px}
.t68-games button{display:flex;flex-direction:column;gap:3px;align-items:flex-start;text-align:left;border:1.5px solid var(--t68line);background:#fff;border-radius:18px;padding:12px;cursor:pointer;color:#1d2650}
.t68-games button span{font-size:26px}.t68-games small{color:var(--t68mut)}
.t68-gbar{display:flex;justify-content:space-between;background:#1d2650;color:#fff;border-radius:12px;padding:8px 12px;font-weight:900;margin-bottom:10px}
.t68-vf{background:#fff;border:1.5px solid var(--t68line);border-radius:18px;padding:16px;font-size:18px;font-weight:800;text-align:center;line-height:1.7}
.t68-vfb{display:flex;gap:8px;margin-top:10px}.t68-vfb .t68-btn{flex:1}
.t68-gend{text-align:center;background:#fff;border:1.5px solid var(--t68line);border-radius:18px;padding:18px;margin-top:10px}.t68-gend b{display:block;font-size:20px;margin-bottom:6px}
.t68-mem{display:grid;grid-template-columns:repeat(3,1fr);gap:8px}
@media(min-width:620px){.t68-mem{grid-template-columns:repeat(4,1fr)}}
.t68-mc{min-height:84px;border-radius:14px;border:0;background:linear-gradient(135deg,#5b5cf0,#8b5cf6);color:transparent;font-weight:800;font-size:15px;cursor:pointer;padding:6px}
.t68-mc span{visibility:hidden}
.t68-mc.up,.t68-mc.done{background:#fff;border:1.5px solid #c4c8f7;color:#1d2650}.t68-mc.up span,.t68-mc.done span{visibility:visible}
.t68-mc.done{background:#ecfdf3;border-color:#22c55e}
.t68-ord{display:flex;flex-direction:column;gap:6px}.t68-ord .t68-opt{text-align:left;font-size:15px}
.t68-ordok{padding-left:22px}.t68-ordok li{background:#ecfdf3;border-radius:10px;padding:6px 10px;margin:4px 0;font-weight:800}
.t68-small{font-size:13.5px;color:var(--t68mut)}

/* ---------- Lección completa dentro de los cursos ---------- */
.t68-course{background:#fff;border:1.5px solid #d9dcff;border-radius:20px;margin:0 0 14px;overflow:hidden}
.t68-course>summary{list-style:none;display:flex;align-items:center;gap:10px;padding:14px;cursor:pointer;background:linear-gradient(135deg,#eef0ff,#f6edff);font-weight:900;color:#1d2650}
.t68-course>summary::-webkit-details-marker{display:none}
.t68-course>summary span{font-size:26px}.t68-course>summary small{display:block;font-weight:700;color:#56618a;font-size:13px}
.t68-course>summary::after{content:"▾";margin-left:auto;font-size:18px;color:#5b5cf0;transition:transform .2s}
.t68-course[open]>summary::after{transform:rotate(180deg)}
.t68-cbody{padding:12px}
.t68-cbody .t68-sec{box-shadow:none}
.t68-cnav{display:flex;flex-wrap:wrap;gap:8px;margin:6px 0 0}
.t68-link{display:flex;align-items:center;gap:10px;width:100%;text-align:left;border:1.5px solid #d9dcff;background:#f7f7ff;border-radius:16px;padding:12px;margin:0 0 12px;color:#1d2650;cursor:pointer;font-weight:800}
.t68-link span:first-child{font-size:24px}.t68-link small{display:block;color:#56618a;font-weight:700}

#conceptMaster .t68-course h3,#conceptMaster .t68-sec h3{font-size:18px!important;line-height:1.25!important;margin:0 0 10px!important;letter-spacing:0!important}
#conceptMaster .t68-course h4.t68-ctitle{font-size:17px;margin:14px 0 8px;color:#3730a3}
#conceptMaster .t68-course p,#conceptMaster .t68-course li{font-size:15.5px;line-height:1.6}
#conceptMaster .t68-course summary div{font-size:16px;line-height:1.3}
.t68-course .t68-cbody{max-width:100%;overflow:hidden}