:root{
  --coral:#ff7a59;--coral2:#ff9a6f;--yellow:#ffd66b;--mint:#6fd3b8;--green:#45b98d;
  --purple:#8b74e8;--blue:#65a9ed;--ink:#3d3650;--muted:#7d748d;--cream:#fff8ee;--paper:#fffefb;
  --line:#eadfd4;--shadow:0 18px 50px rgba(84,63,101,.13);--radius:26px;
}
*{box-sizing:border-box}html{min-width:320px}body{margin:0;font-family:"Trebuchet MS","Segoe UI",system-ui,sans-serif;color:var(--ink);background:linear-gradient(180deg,#fff9ef 0%,#f8f5ff 48%,#eef9f6 100%);min-height:100vh}button,input{font:inherit}.hidden{display:none!important}.view{display:none}.view.active{display:block}.topbar{position:sticky;top:0;z-index:20;display:flex;justify-content:space-between;align-items:center;padding:12px clamp(14px,4vw,30px);background:rgba(255,254,250,.9);backdrop-filter:blur(14px);border-bottom:1px solid rgba(232,218,205,.85)}.brand{display:flex;align-items:center;gap:10px;border:0;background:none;color:var(--ink);text-align:left;cursor:pointer}.logo{width:42px;height:42px;border-radius:15px;display:grid;place-items:center;color:white;font-size:29px;font-weight:900;background:linear-gradient(145deg,var(--coral),#ffb35c);box-shadow:0 8px 18px rgba(255,122,89,.28)}.brand strong{display:block;font-size:16px;letter-spacing:.03em}.brand small{display:block;color:var(--muted);font-size:11px;margin-top:1px}.top-actions{display:flex;gap:8px}.icon-btn{width:42px;height:42px;border:1px solid var(--line);background:white;border-radius:14px;cursor:pointer;font-size:18px}
main{max-width:1300px;margin:0 auto;padding:clamp(18px,4vw,42px)}.hero-card{display:grid;grid-template-columns:1.05fr .95fr;gap:28px;align-items:center;background:linear-gradient(135deg,#fff2d9,#ffe8dc 48%,#eee8ff);border:1px solid #f1deca;border-radius:34px;padding:clamp(28px,5vw,58px);box-shadow:var(--shadow);overflow:hidden;position:relative}.hero-card:after{content:"";position:absolute;right:-80px;top:-80px;width:220px;height:220px;border-radius:50%;background:rgba(255,214,107,.35)}.hero-copy{position:relative;z-index:1}.eyebrow{font-size:12px;font-weight:900;letter-spacing:.07em;text-transform:uppercase;color:#8a5b52}.eyebrow.warm{color:#a36935}.hero-copy h1{font-size:clamp(38px,6vw,70px);line-height:.98;margin:12px 0 18px;max-width:650px}.hero-copy h1 span{color:var(--coral)}.hero-copy p{font-size:clamp(17px,2vw,20px);line-height:1.55;color:#685f76;max-width:620px}.start-panel{position:relative;z-index:1;background:rgba(255,255,255,.9);border:1px solid rgba(232,218,205,.9);border-radius:26px;padding:24px;box-shadow:0 12px 34px rgba(89,63,81,.1)}label{font-size:13px;font-weight:800;color:#5b5168}input{width:100%;margin-top:7px;border:2px solid #eadfd4;background:white;border-radius:16px;padding:13px 14px;outline:none;color:var(--ink);font-size:19px;font-weight:800}input:focus{border-color:var(--purple);box-shadow:0 0 0 4px rgba(139,116,232,.11)}.operation-input{display:grid;grid-template-columns:1fr auto 1fr;align-items:end;gap:10px;margin:16px 0}.times{font-size:34px;font-weight:900;color:var(--coral);padding-bottom:10px}.btn{border:0;border-radius:16px;padding:13px 18px;font-weight:900;cursor:pointer;transition:.18s transform,.18s box-shadow}.btn:active{transform:scale(.98)}.btn.primary{background:linear-gradient(135deg,var(--coral),#ff9e59);color:white;box-shadow:0 10px 22px rgba(255,122,89,.25)}.btn.soft{background:#eee8ff;color:#5d4bb0}.btn.ghost{background:#fff8e8;color:#85612d;border:1px solid #f0ddaf}.full{width:100%}.quick-examples{display:flex;gap:7px;align-items:center;flex-wrap:wrap;margin-top:14px;color:var(--muted);font-size:12px}.quick-examples button{border:1px solid #e9dacf;background:#fffaf4;border-radius:999px;padding:6px 9px;color:#7a5c62;cursor:pointer}.limit-note{font-size:11px;color:#9b91a5;text-align:center;margin:12px 0 0}.feature-row{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin-top:20px}.feature-row article{background:rgba(255,255,255,.83);border:1px solid var(--line);border-radius:22px;padding:20px;box-shadow:0 10px 28px rgba(82,65,97,.07)}.feature-row article>span{font-size:28px}.feature-row strong{display:block;margin:8px 0 5px}.feature-row p{margin:0;color:var(--muted);font-size:13px;line-height:1.45}
.lesson-layout{display:grid;grid-template-columns:minmax(0,1.35fr) minmax(300px,.65fr);gap:22px;align-items:start}.board-card,.coach-card{background:rgba(255,255,255,.93);border:1px solid var(--line);border-radius:28px;box-shadow:var(--shadow)}.board-card{padding:24px}.board-head{display:flex;justify-content:space-between;align-items:flex-start;gap:16px}.board-head h2{font-size:clamp(25px,4vw,38px);margin:5px 0;color:#544768}.progress-pill{min-width:155px;font-size:11px;color:var(--muted);font-weight:800;text-align:right}.progress-pill>div{height:8px;border-radius:99px;background:#f1e9e2;margin-top:7px;overflow:hidden}.progress-pill i{display:block;width:0%;height:100%;border-radius:inherit;background:linear-gradient(90deg,var(--mint),var(--purple));transition:width .35s ease}.math-board-wrap{display:flex;justify-content:center;overflow:auto;padding:28px 4px 12px}.math-board{--cell:clamp(42px,7vw,70px);display:grid;gap:0;font-family:"Courier New",monospace;font-weight:900;font-variant-numeric:tabular-nums;min-width:max-content;position:relative}.mcell{width:var(--cell);height:calc(var(--cell)*.86);display:grid;place-items:center;font-size:clamp(26px,5vw,44px);position:relative;border-radius:10px;transition:.2s}.mcell.small{height:30px;font-size:clamp(15px,2.5vw,21px);color:#a26d39}.mcell.operator{font-size:clamp(24px,4vw,36px);color:var(--coral)}.mcell.line{height:5px;background:#61556b;border-radius:99px;margin:4px 1px}.mcell.active-cell{background:#dff8ed;box-shadow:0 0 0 3px #78d8b8,0 0 22px rgba(111,211,184,.55);animation:pulseCell 1.15s infinite}.mcell.carry-active{background:#fff0b8;color:#a16815;box-shadow:0 0 0 3px #ffd66b;animation:pulseCarry 1s infinite}.mcell.placed{color:#4d4460}.mcell.partial{color:#7b5ca9}.mcell.total{color:#cf6146}.mcell.placeholder{color:#c8becf}.row-label{position:absolute;left:100%;white-space:nowrap;font-family:"Trebuchet MS",sans-serif;font-size:11px;font-weight:800;color:#9a91a3;padding-left:8px;top:50%;transform:translateY(-50%)}@keyframes pulseCell{50%{box-shadow:0 0 0 6px rgba(120,216,184,.25),0 0 30px rgba(111,211,184,.45)}}@keyframes pulseCarry{50%{transform:scale(1.1);box-shadow:0 0 0 7px rgba(255,214,107,.2)}}.board-legend{text-align:center;color:var(--muted);font-size:12px;margin-top:10px}.coach-card{padding:24px;position:sticky;top:82px}.coach-avatar{width:68px;height:68px;border-radius:23px;display:grid;place-items:center;font-size:36px;background:linear-gradient(145deg,#fff1b8,#ffe3d2);box-shadow:0 10px 22px rgba(160,108,50,.13)}.coach-title{font-size:12px;font-weight:900;color:#a27455;text-transform:uppercase;letter-spacing:.08em;margin-top:14px}.coach-message{font-size:22px;line-height:1.4;font-weight:800;margin:8px 0 18px;color:#554b63}.coach-message strong{color:var(--coral)}.answer-zone{padding:16px;background:#f8f5ff;border-radius:20px;border:1px solid #e7def7}.answer-zone input{text-align:center;font-size:30px;letter-spacing:.05em;margin-bottom:10px}.hint-box{background:#fff6d7;border:1px solid #f1dc9a;color:#725826;border-radius:16px;padding:13px;margin-bottom:12px;line-height:1.45;font-size:13px}.feedback{border-radius:16px;padding:13px;margin-top:12px;font-weight:800;font-size:13px}.feedback.good{background:#e2f8ef;color:#2f7b62}.feedback.bad{background:#ffe9e3;color:#a14d3e}.coach-card>.btn{margin-top:10px}
.finish-card{max-width:760px;margin:40px auto;background:linear-gradient(145deg,#fffdf8,#fff0dc 50%,#eeeaff);border:1px solid #ecdccb;border-radius:34px;padding:clamp(30px,6vw,60px);text-align:center;box-shadow:var(--shadow)}.confetti{letter-spacing:12px;font-size:24px}.finish-badge{font-size:74px;margin:12px}.finish-card h1{font-size:clamp(36px,7vw,62px);margin:5px}.finish-card p{color:var(--muted);font-size:18px}.final-operation{display:inline-block;margin:18px auto;padding:17px 24px;border-radius:20px;background:white;border:1px solid var(--line);font-size:clamp(25px,5vw,42px);font-family:"Courier New",monospace;font-weight:900;color:#675375}.finish-actions{display:flex;justify-content:center;gap:10px;flex-wrap:wrap;margin-top:16px}.toast{position:fixed;z-index:99;left:50%;bottom:22px;transform:translateX(-50%);background:#4f455e;color:white;border-radius:999px;padding:11px 16px;font-size:13px;font-weight:800;box-shadow:0 10px 28px rgba(0,0,0,.18);text-align:center;max-width:90%}
@media(max-width:900px){.hero-card{grid-template-columns:1fr}.lesson-layout{grid-template-columns:1fr}.coach-card{position:static}.feature-row{grid-template-columns:1fr 1fr}.math-board{--cell:clamp(40px,10vw,62px)}}
@media(max-width:600px){main{padding:14px 9px 90px}.topbar{padding:9px 10px}.brand strong{font-size:13px}.brand small{font-size:9px}.logo{width:38px;height:38px}.hero-card{padding:23px 16px;border-radius:25px}.hero-copy h1{font-size:39px}.start-panel{padding:17px;border-radius:21px}.operation-input{grid-template-columns:1fr auto 1fr;gap:6px}.operation-input input{font-size:17px;padding:12px 8px}.times{font-size:28px}.feature-row{grid-template-columns:1fr}.feature-row article{padding:16px}.board-card,.coach-card{padding:16px;border-radius:23px}.board-head{flex-direction:column}.progress-pill{width:100%;text-align:left}.math-board-wrap{padding:20px 0 8px}.math-board{--cell:clamp(35px,10.5vw,51px)}.mcell{font-size:clamp(23px,8vw,34px)}.row-label{display:none}.coach-message{font-size:20px}.coach-card{padding-bottom:20px}.finish-actions .btn{width:100%}}
@media(max-width:380px){.brand small{display:none}.hero-copy h1{font-size:34px}.quick-examples span{width:100%}.math-board{--cell:34px}.mcell{font-size:22px}}


/* v2 · Maite escribe dentro de la operación */
.mcell.interact-cell{
  background:#ffe0df;
  color:#d63535;
  box-shadow:0 0 0 3px #ff625d,0 0 28px rgba(255,74,69,.38);
  animation:pulseInteract 1s infinite;
  z-index:2;
}
.mcell.sum-source-cell{
  background:#fff0cc;
  color:#b46c19;
  box-shadow:0 0 0 3px #ffc861;
}
.mcell.entry-cell{
  padding:2px;
  z-index:3;
}
.mcell.write-entry{
  background:#dff8ed;
  box-shadow:0 0 0 4px #56c99f,0 0 30px rgba(70,192,148,.42);
  animation:pulseEntry 1s infinite;
}
.mcell.carry-entry{
  background:#fff0b8;
  box-shadow:0 0 0 4px #ffc83d,0 0 28px rgba(255,200,61,.42);
  animation:pulseCarry 1s infinite;
}
.board-entry-input{
  width:100%;height:100%;margin:0;padding:0;border:0!important;border-radius:8px;
  background:transparent!important;box-shadow:none!important;outline:none;
  text-align:center;font:inherit;font-size:inherit;font-weight:900;color:#3f3a52;
  caret-color:#4b3f63;
}
.carry-entry .board-entry-input{color:#9d6713}
.board-entry-input.correct-entry{color:#268267}
.board-entry-input.shake{animation:shakeEntry .28s linear}
@keyframes pulseInteract{50%{transform:scale(1.08);box-shadow:0 0 0 6px rgba(255,98,93,.18),0 0 35px rgba(255,74,69,.35)}}
@keyframes pulseEntry{50%{box-shadow:0 0 0 7px rgba(86,201,159,.18),0 0 35px rgba(70,192,148,.42)}}
@keyframes shakeEntry{0%,100%{transform:translateX(0)}25%{transform:translateX(-5px)}75%{transform:translateX(5px)}}
.board-legend{font-weight:800;line-height:1.45;padding:9px 12px;border-radius:14px;background:#fffaf2;border:1px solid #efe0cf;max-width:680px;margin:12px auto 0}
.answer-zone.hidden{display:none!important}
@media(max-width:600px){
  .board-legend{font-size:11px;padding:8px 9px}
  .mcell.interact-cell{box-shadow:0 0 0 2px #ff625d,0 0 18px rgba(255,74,69,.32)}
  .mcell.write-entry,.mcell.carry-entry{box-shadow:0 0 0 3px currentColor,0 0 20px rgba(70,192,148,.28)}
}
@media(prefers-reduced-motion:reduce){.mcell.interact-cell,.mcell.write-entry,.mcell.carry-entry,.board-entry-input.shake{animation:none!important}}


/* v3 · Mensajes de papá */
.papa-welcome{display:flex;gap:11px;align-items:flex-start;margin-top:18px;padding:13px 15px;border-radius:18px;background:linear-gradient(135deg,#fff6cf,#fff0df);border:1px solid #f1dca7;max-width:620px;color:#6f5a4c}.papa-welcome>span{font-size:24px;line-height:1}.papa-welcome strong{display:block;color:#8d6248;font-size:13px}.papa-welcome p{font-size:14px!important;line-height:1.45!important;margin:3px 0 0!important;color:#756253!important}.papa-message{display:flex;gap:10px;align-items:flex-start;margin:-3px 0 16px;padding:12px 13px;border-radius:18px;background:linear-gradient(135deg,#fff8d9,#fff0e4);border:1px solid #f0dcaa;box-shadow:0 6px 16px rgba(145,101,54,.08)}.papa-message>span{font-size:21px;line-height:1}.papa-message small{display:block;color:#a16b48;font-size:9px;font-weight:900;letter-spacing:.08em;margin-bottom:3px}.papa-message p{margin:0;color:#6f594d;font-size:13px;line-height:1.45;font-weight:700}.papa-pop{animation:papaPop .32s ease}.papa-finish{display:flex;gap:12px;align-items:flex-start;text-align:left;max-width:610px;margin:18px auto;padding:16px 17px;border-radius:20px;background:linear-gradient(135deg,#fff7ce,#ffe9dc);border:1px solid #efd6a5;box-shadow:0 8px 24px rgba(142,97,55,.09)}.papa-finish>span{font-size:28px}.papa-finish strong{display:block;color:#8f6047;margin-bottom:4px}.papa-finish p{margin:0;color:#6e5a4e;font-size:15px;line-height:1.55}@keyframes papaPop{0%{transform:scale(.985);opacity:.75}100%{transform:scale(1);opacity:1}}@media(max-width:600px){.papa-welcome{padding:11px 12px}.papa-message{padding:11px 12px}.papa-message p{font-size:12.5px}.papa-finish{padding:14px}.papa-finish p{font-size:14px}}@media(prefers-reduced-motion:reduce){.papa-pop{animation:none!important}}