/* ============================================================================
   LexiCoil — Sistema de diseño de pantallas (responsive: móvil / tablet / escritorio)
   ESTE ARCHIVO ES LA FORMA CANÓNICA. Todas las pantallas usan estas clases.
   Breakpoints:  móvil <640px (1 col) · tablet 640–1024px (2 col) · escritorio >1024px (máx 1200px centrado)
   Reglas clave: cabecera mínima (sin pestañas), contenedor centrado, barra inferior fija que en
   móvil se apila, objetivos táctiles >=44px, un solo acento azul protagonista por pantalla.
   ========================================================================== */
/* Canonical tokens — align with lexicoil-design-system.css */
:root{
  --lc-font:'Poppins',system-ui,sans-serif;
  --brand:#2563eb; --brand-dark:#1d4ed8; --brand-light:#dbeafe; --lc-teal:#06b6d4;
  --bg:#f8fafc; --bg2:#fff; --bg3:#f1f5f9;
  --border:rgba(15,23,42,.08);
  --text-primary:#0f172a; --text-secondary:#475569; --text-muted:#94a3b8; --text:var(--text-primary);
  --green:#10b981; --amber:#f59e0b; --purple:#7f77dd; --red:#ef4444;
  --radius-md:12px; --radius-lg:16px;
  --tap:44px;            /* objetivo táctil mínimo */
  --maxw:1200px;         /* ancho máximo en escritorio (design system) */
}
*{box-sizing:border-box}
html,body{margin:0}
body{font-family:var(--lc-font);background:var(--bg);color:var(--text);line-height:1.55;-webkit-text-size-adjust:100%}

/* ---- Cabecera mínima (sustituye a las 4 pestañas) ---- */
.appbar{position:sticky;top:0;z-index:20;display:flex;align-items:center;gap:12px;
  padding:10px 16px;background:rgba(255,255,255,.92);backdrop-filter:saturate(1.1) blur(6px);
  border-bottom:1px solid var(--border)}
.appbar .brand{display:flex;align-items:center;gap:8px;font-weight:700;font-size:17px;color:var(--text);text-decoration:none}
.appbar .logo{width:26px;height:26px;border-radius:7px;background:linear-gradient(135deg,var(--brand),var(--teal));flex:none}
.appbar .back{display:inline-flex;align-items:center;gap:6px;min-height:var(--tap);padding:0 8px;
  font-size:14px;font-weight:600;color:var(--text-secondary);background:none;border:none;cursor:pointer;font-family:var(--lc-font)}
.appbar .ctxname{font-weight:700;color:var(--text)}
.appbar .spacer{flex:1}
.appbar .acct{width:36px;height:36px;border-radius:50%;background:var(--bg3);border:1px solid var(--border);
  display:flex;align-items:center;justify-content:center;font-weight:700;font-size:13px;color:var(--text-secondary);cursor:pointer}
.appbar .badge-soft{font-size:10px;font-weight:700;text-transform:uppercase;letter-spacing:.06em;
  color:var(--amber);background:rgba(245,158,11,.12);padding:4px 10px;border-radius:99px}

/* ---- Contenedor centrado y responsive ---- */
.container{width:100%;max-width:var(--maxw);margin:0 auto;padding:18px 16px 96px}
@media(min-width:640px){ .container{padding:24px 24px 100px} }
@media(min-width:1024px){ .container{padding:32px 32px 110px} }

/* ---- Tipografía ---- */
.h1{font-size:22px;font-weight:700;letter-spacing:-.02em;margin:0 0 4px}
.h2{font-size:19px;font-weight:700;letter-spacing:-.01em;margin:0}
.kicker{font-size:11px;font-weight:700;letter-spacing:.12em;text-transform:uppercase;color:var(--brand);margin:0 0 14px}
.seclbl{font-size:10px;font-weight:700;letter-spacing:.1em;text-transform:uppercase;color:var(--text-muted);margin:0 0 10px;
  display:flex;align-items:center;justify-content:space-between;gap:8px}
.lede{font-size:14px;font-weight:500;color:var(--text-secondary);margin:0 0 18px}
.note{font-size:12px;font-weight:500;color:var(--text-muted);margin-top:12px;line-height:1.5}
@media(min-width:640px){ .h1{font-size:26px} .h2{font-size:21px} }

/* ---- Rejillas: 1 col móvil, 2 col tablet+, auto para tarjetas ---- */
.grid{display:grid;gap:14px;grid-template-columns:1fr}
@media(min-width:640px){ .grid.cols2,.grid.cols3{grid-template-columns:1fr 1fr} }
@media(min-width:1024px){ .grid.cols3{grid-template-columns:1fr 1fr 1fr} }
.grid.cards{grid-template-columns:1fr}
@media(min-width:560px){ .grid.cards{grid-template-columns:repeat(auto-fill,minmax(260px,1fr))} }

/* ---- Tarjetas ---- */
.card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius-lg);padding:18px;transition:border-color .2s;margin-bottom:14px}
.card.click{cursor:pointer}
.card.click:hover{border-color:var(--brand)}
.card.accent{border-color:var(--brand);background:var(--brand-light)}      /* protagonista (único por pantalla) */
.card.dashed{border:1.5px dashed var(--border);background:transparent;display:flex;flex-direction:column;
  align-items:center;justify-content:center;color:var(--text-muted);min-height:150px}
.card.span{grid-column:1/-1}

/* ---- Botones (tap >=44px) ---- */
.btn{display:inline-flex;align-items:center;justify-content:center;min-height:var(--tap);
  padding:0 20px;border-radius:12px;font-family:var(--lc-font);font-size:15px;font-weight:700;
  cursor:pointer;border:1px solid transparent;text-decoration:none}
.btn-primary{background:var(--brand);color:#fff}
.btn-primary:hover{background:var(--brand-dark)}
.btn-secondary{background:var(--bg2);color:var(--text);border-color:var(--border)}
.btn-block{display:flex;width:100%;max-width:320px;margin:16px auto 0}
.cta-link{display:inline-flex;align-items:center;gap:6px;min-height:36px;font-size:13px;font-weight:700;color:var(--brand)}

/* ---- Barra inferior fija (responsive): fila en tablet+, apilada a ancho completo en móvil ---- */
.footbar{position:fixed;left:0;right:0;bottom:0;z-index:20;background:var(--bg2);border-top:1px solid var(--border);
  padding:12px 16px calc(12px + env(safe-area-inset-bottom));display:flex;align-items:center;gap:12px}
.footbar .summary{flex:1;font-size:12px;font-weight:600;color:var(--text-secondary)}
.footbar .summary b{color:var(--text)}
.footbar .btn{white-space:nowrap}
@media(max-width:639px){
  .footbar{flex-direction:column;align-items:stretch}
  .footbar .summary{text-align:center;order:1}
  .footbar .btn{order:2;width:100%}
}
@media(min-width:640px){ .footbar{justify-content:center} .footbar>*{max-width:var(--maxw);width:100%} .footbar{padding-left:24px;padding-right:24px} }

/* ---- Badges / pills ---- */
.pill{font-size:10px;font-weight:700;padding:3px 8px;border-radius:6px;background:var(--bg3);color:var(--text-secondary)}
.badge-due{font-size:9px;font-weight:700;text-transform:uppercase;letter-spacing:.05em;color:#fff;background:var(--amber);padding:2px 7px;border-radius:6px}
.badge-soon{font-size:9px;font-weight:700;text-transform:uppercase;letter-spacing:.05em;color:var(--amber);background:rgba(245,158,11,.12);padding:2px 7px;border-radius:6px}

/* ---- Chips (selección de palabras, tap-friendly) ---- */
.chips{display:flex;flex-wrap:wrap;gap:8px}
.chip{display:inline-flex;align-items:center;gap:7px;min-height:40px;padding:0 13px;border:1px solid var(--border);
  border-radius:99px;font-size:13px;font-weight:600;color:var(--text-secondary);cursor:pointer;background:var(--bg2);font-family:var(--lc-font)}
.chip.on{border-color:var(--brand);background:var(--brand-light);color:var(--brand)}
.chip .tk{width:16px;height:16px;border-radius:4px;border:1.5px solid var(--text-muted);display:inline-flex;align-items:center;justify-content:center;font-size:10px;color:#fff}
.chip.on .tk{background:var(--brand);border-color:var(--brand)}
.chip .due{width:6px;height:6px;border-radius:50%;background:var(--amber)}

/* ---- Pestañas y listas (filas tap >=48px) ---- */
.tabs{display:flex;gap:7px;flex-wrap:wrap;margin-bottom:12px;align-items:center}
.tab{min-height:38px;display:inline-flex;align-items:center;padding:0 13px;border-radius:99px;border:1px solid var(--border);
  font-size:12px;font-weight:600;color:var(--text-secondary);cursor:pointer;background:var(--bg2);font-family:var(--lc-font)}
.tab.on{background:var(--text);color:#fff;border-color:var(--text)}
.list{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius-lg);overflow:hidden}
.row{display:flex;align-items:center;justify-content:space-between;gap:12px;min-height:52px;padding:10px 14px;border-bottom:1px solid var(--border);font-size:14px}
.row:last-child{border-bottom:0}
.chk{width:20px;height:20px;border-radius:6px;border:1.5px solid var(--text-muted);flex:none}
.chk.on{background:var(--brand);border-color:var(--brand)}
.icbtn{width:var(--tap);height:var(--tap);display:flex;align-items:center;justify-content:center;color:var(--text-muted);cursor:pointer;font-size:14px}

/* ---- Examen ---- */
.examhead{display:flex;align-items:center;gap:12px;margin-bottom:14px}
.progress{flex:1;height:8px;background:var(--bg3);border-radius:99px;overflow:hidden}
.progress > i{display:block;height:100%;background:linear-gradient(90deg,var(--brand),var(--teal));border-radius:99px}
.timer{font-family:ui-monospace,monospace;font-weight:700;color:var(--text)}
.modechip{font-size:10px;font-weight:700;text-transform:uppercase;letter-spacing:.06em;padding:4px 9px;border-radius:99px;background:var(--bg3);color:var(--text-secondary)}
.passage{font-size:15px;line-height:1.85;color:var(--text);background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius-lg);padding:16px;margin-bottom:12px}
.qtxt{font-size:14px;line-height:1.7;color:var(--text);margin:0 0 10px}
.w{border-bottom:1px dashed var(--text-muted);cursor:pointer}
.w.marked{background:rgba(245,158,11,.18);border-bottom:0;border-radius:3px;padding:0 2px}
.w.saved{background:rgba(16,185,129,.16);border-bottom:0;border-radius:3px;padding:0 2px;color:var(--green);font-weight:700}
.opt{display:block;min-height:var(--tap);border:1px solid var(--border);border-radius:10px;padding:11px 14px;font-size:14px;font-weight:600;color:var(--text);margin-top:10px;cursor:pointer;width:100%;text-align:left;font-family:var(--lc-font);background:var(--bg2)}
.opt:hover{border-color:var(--brand)}
.opt.correct{border-color:var(--green);background:rgba(16,185,129,.1)}
.opt.wrong{border-color:var(--red);background:rgba(239,68,68,.08)}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);border:0}

/* ---- Foco accesible (teclado) ---- */
:where(a,button,.btn,.tab,.chip,.opt,.card.click,.icbtn,.lvl,.tile,.mode):focus-visible{
  outline:3px solid var(--brand);outline-offset:2px;border-radius:10px}
/* ---- Estados utilitarios ---- */
.spinner{width:34px;height:34px;border-radius:50%;border:3px solid var(--bg3);border-top-color:var(--brand);animation:spin .8s linear infinite;margin:0 auto;flex-shrink:0}
@keyframes spin{to{transform:rotate(360deg)}}
.statecard{text-align:center;padding:34px 20px}
.statecard .ic{font-size:30px}
.statecard h3{font-size:16px;font-weight:700;margin:12px 0 6px}
.statecard p{font-size:13px;font-weight:500;color:var(--text-secondary);margin:0 auto;max-width:360px;line-height:1.5}
.btn[disabled]{opacity:.45;cursor:not-allowed}
.err{color:var(--red);text-align:center;font-size:13px;font-weight:600;padding:20px}