/* ============================================================
   EXÁMENES LIBRES · 5° BÁSICO — sistema de diseño
   Producto WhiteBox Juegos. Tema "Misión de Estudio":
   tinta ciruela, coral cálido, ámbar logro, papel crema.
   Diseño propio, no reutiliza bio (teal) ni física (azul).
   Sin build, sin frameworks. Un solo archivo de tokens+layout.
   ============================================================ */

:root {
  /* --- paleta --- */
  --paper:      #fbf7f0;   /* crema */
  --paper-2:    #fffdf9;   /* tarjeta */
  --ink:        #2a1f38;   /* tinta ciruela */
  --ink-soft:   #4c3f5e;
  --muted:      #8a7f97;
  --line:       #e7ddd0;
  --line-2:     #efe7db;

  --coral:      #e8623d;   /* acento principal */
  --coral-ink:  #b8431f;
  --coral-wash: #fcefe9;
  --amber:      #f2a93b;   /* logro / estrellas */
  --amber-ink:  #b9781a;
  --teal:       #2f9c8b;   /* correcto / avance */
  --teal-wash:  #e6f4f1;
  --plum:       #7a4bc4;   /* eje / etiqueta */
  --plum-wash:  #f0eafb;
  --wrong:      #d8455f;   /* incorrecto */
  --wrong-wash: #fdecef;

  /* por asignatura (acento de sección) */
  --leng: #e8623d;   /* coral */
  --mate: #2f6fb0;   /* azul */
  --cien: #2f9c8b;   /* teal */
  --hist: #b06a2c;   /* tierra */
  --ingl: #7a4bc4;   /* plum */

  --radius:     18px;
  --radius-sm:  12px;
  --measure:    68ch;
  --shadow:     0 2px 4px rgba(42,31,56,.05), 0 10px 30px rgba(42,31,56,.07);
  --shadow-sm:  0 1px 2px rgba(42,31,56,.06), 0 4px 12px rgba(42,31,56,.05);
  --font: "Nunito", "Baloo 2", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink);
  background: var(--paper);
  line-height: 1.62;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

/* fondo con textura suave (sin imágenes) */
body {
  background-image:
    radial-gradient(circle at 12% 8%, rgba(242,169,59,.08), transparent 42%),
    radial-gradient(circle at 88% 4%, rgba(122,75,196,.07), transparent 40%),
    radial-gradient(circle at 78% 92%, rgba(47,156,139,.07), transparent 46%);
  background-attachment: fixed;
}

a { color: var(--coral-ink); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ---------- layout ---------- */
.wrap { max-width: 1080px; margin: 0 auto; padding: 0 20px; }
.wrap-narrow { max-width: 760px; margin: 0 auto; padding: 0 20px; }

/* ---------- barra superior ---------- */
.topbar {
  position: sticky; top: 0; z-index: 40;
  background: rgba(251,247,240,.86);
  backdrop-filter: saturate(1.4) blur(8px);
  border-bottom: 1px solid var(--line);
}
.topbar .wrap { display: flex; align-items: center; gap: 14px; height: 60px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; letter-spacing: -.02em; color: var(--ink); }
.brand .logo {
  width: 34px; height: 34px; border-radius: 10px;
  background: linear-gradient(135deg, var(--coral), var(--amber));
  display: grid; place-items: center; color: #fff; font-size: 19px; box-shadow: var(--shadow-sm);
}
.brand small { display: block; font-weight: 700; font-size: .68rem; color: var(--muted); letter-spacing: .06em; text-transform: uppercase; margin-top: -3px; }
.topbar .spacer { flex: 1; }
.topbar nav { display: flex; gap: 4px; flex-wrap: wrap; }
.topbar nav a {
  padding: 7px 12px; border-radius: 999px; font-weight: 700; font-size: .9rem;
  color: var(--ink-soft);
}
.topbar nav a:hover { background: var(--coral-wash); color: var(--coral-ink); text-decoration: none; }
.topbar nav a.active { background: var(--ink); color: #fff; }

/* ---------- hero ---------- */
.hero { padding: 46px 0 28px; }
.hero .kicker {
  display: inline-flex; align-items: center; gap: 8px;
  font-weight: 800; font-size: .78rem; letter-spacing: .1em; text-transform: uppercase;
  color: var(--coral-ink); background: var(--coral-wash);
  padding: 6px 14px; border-radius: 999px; margin-bottom: 16px;
}
.hero h1 {
  font-size: clamp(2.1rem, 5.5vw, 3.4rem); font-weight: 800; letter-spacing: -.03em;
  line-height: 1.05; margin: 0 0 14px;
}
.hero h1 .hl { color: var(--coral); }
.hero .lede { max-width: 60ch; font-size: 1.16rem; color: var(--ink-soft); margin: 0 0 22px; }
.hero .facts { display: flex; flex-wrap: wrap; gap: 10px; }
.chip {
  display: inline-flex; align-items: center; gap: 7px;
  background: var(--paper-2); border: 1px solid var(--line);
  padding: 8px 14px; border-radius: 999px; font-weight: 700; font-size: .9rem; color: var(--ink-soft);
  box-shadow: var(--shadow-sm);
}
.chip b { color: var(--ink); }

/* ---------- grilla de asignaturas ---------- */
.subjects { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 18px; margin: 8px 0 40px; }
.subject-card {
  position: relative; display: block; background: var(--paper-2);
  border: 1px solid var(--line); border-radius: var(--radius);
  padding: 22px 22px 20px; text-decoration: none; color: inherit;
  box-shadow: var(--shadow-sm); transition: transform .16s, box-shadow .16s, border-color .16s;
  overflow: hidden;
}
.subject-card::before {
  content: ""; position: absolute; left: 0; top: 0; bottom: 0; width: 6px; background: var(--acc, var(--coral));
}
.subject-card:hover { transform: translateY(-3px); box-shadow: var(--shadow); border-color: var(--acc, var(--coral)); text-decoration: none; }
.subject-card .ico {
  width: 52px; height: 52px; border-radius: 14px; display: grid; place-items: center;
  font-size: 27px; margin-bottom: 14px; background: color-mix(in srgb, var(--acc) 14%, #fff); color: var(--acc);
}
.subject-card h3 { margin: 0 0 6px; font-size: 1.28rem; font-weight: 800; letter-spacing: -.02em; }
.subject-card p { margin: 0 0 14px; color: var(--muted); font-size: .95rem; line-height: 1.5; }
.subject-card .meta { display: flex; gap: 14px; font-size: .82rem; font-weight: 700; color: var(--ink-soft); }
.subject-card .meta span { display: inline-flex; align-items: center; gap: 5px; }
.subject-card .go { position: absolute; right: 20px; top: 24px; color: var(--acc); font-size: 1.3rem; opacity: .0; transition: opacity .16s, transform .16s; }
.subject-card:hover .go { opacity: 1; transform: translateX(3px); }

/* ---------- secciones ---------- */
.section { padding: 8px 0 40px; }
.section-head { border-bottom: 2px solid var(--line); padding-bottom: 12px; margin-bottom: 22px; }
.section-head h2 { margin: 0; font-size: 1.6rem; font-weight: 800; letter-spacing: -.02em; }
.section-head p { margin: 6px 0 0; color: var(--muted); }

/* dos columnas de acción por asignatura */
.actions { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.action {
  display: flex; gap: 14px; align-items: flex-start; background: var(--paper-2);
  border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 18px; text-decoration: none; color: inherit;
  box-shadow: var(--shadow-sm); transition: transform .14s, border-color .14s;
}
.action:hover { transform: translateY(-2px); border-color: var(--acc, var(--coral)); text-decoration: none; }
.action .ico { flex: none; width: 44px; height: 44px; border-radius: 11px; display: grid; place-items: center; font-size: 22px; background: color-mix(in srgb, var(--acc, var(--coral)) 13%, #fff); color: var(--acc, var(--coral)); }
.action h4 { margin: 0 0 3px; font-size: 1.05rem; font-weight: 800; }
.action p { margin: 0; font-size: .88rem; color: var(--muted); }

/* ---------- caja de nota ---------- */
.callout {
  display: flex; gap: 14px; background: var(--amber); background: linear-gradient(135deg, #fff6e6, #fdeccb);
  border: 1px solid #f0d79a; border-radius: var(--radius-sm); padding: 16px 18px; margin: 22px 0;
}
.callout .ico { font-size: 24px; }
.callout b { color: var(--amber-ink); }

/* ---------- botones ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 9px; cursor: pointer;
  font-family: var(--font); font-weight: 800; font-size: 1rem;
  padding: 13px 24px; border-radius: 999px; border: 0;
  background: var(--coral); color: #fff; box-shadow: var(--shadow-sm);
  transition: transform .12s, box-shadow .12s, background .12s; text-decoration: none;
}
.btn:hover { transform: translateY(-2px); box-shadow: var(--shadow); text-decoration: none; }
.btn:active { transform: translateY(0); }
.btn.ghost { background: var(--paper-2); color: var(--ink); border: 1px solid var(--line); }
.btn.ghost:hover { border-color: var(--coral); color: var(--coral-ink); }
.btn.big { font-size: 1.1rem; padding: 15px 30px; }
.btn[disabled] { opacity: .5; cursor: not-allowed; transform: none; }

/* ---------- footer ---------- */
.foot { border-top: 1px solid var(--line); padding: 26px 0 46px; color: var(--muted); font-size: .9rem; }
.foot .wrap { display: flex; flex-wrap: wrap; gap: 8px 20px; align-items: center; }
.foot .spacer { flex: 1; }

/* ============================================================
   MOTOR DE EXAMEN (examen.js)
   ============================================================ */
.exam { max-width: 760px; margin: 0 auto; padding: 20px; }

/* barra de progreso fija */
.exam-bar {
  position: sticky; top: 60px; z-index: 30; background: rgba(251,247,240,.9);
  backdrop-filter: blur(6px); border-bottom: 1px solid var(--line);
  display: flex; align-items: center; gap: 14px; padding: 12px 20px; margin: 0 -20px 20px;
}
.exam-bar .prog { flex: 1; height: 10px; background: var(--line-2); border-radius: 999px; overflow: hidden; }
.exam-bar .prog i { display: block; height: 100%; background: linear-gradient(90deg, var(--acc, var(--coral)), var(--amber)); border-radius: 999px; transition: width .3s; }
.exam-bar .count { font-weight: 800; font-size: .92rem; color: var(--ink-soft); white-space: nowrap; }
.exam-bar .timer { font-weight: 800; font-variant-numeric: tabular-nums; padding: 5px 12px; border-radius: 999px; background: var(--paper-2); border: 1px solid var(--line); white-space: nowrap; }
.exam-bar .timer.low { color: #fff; background: var(--wrong); border-color: var(--wrong); }

/* tarjeta de pregunta */
.q-card { background: var(--paper-2); border: 1px solid var(--line); border-radius: var(--radius); padding: 26px 26px 22px; box-shadow: var(--shadow-sm); }
.q-eje { display: inline-block; font-size: .72rem; font-weight: 800; letter-spacing: .08em; text-transform: uppercase; color: var(--plum); background: var(--plum-wash); padding: 4px 11px; border-radius: 999px; margin-bottom: 14px; }
.q-stem { font-size: 1.18rem; font-weight: 700; line-height: 1.5; margin: 0 0 8px; }
.q-context { background: var(--paper); border-left: 3px solid var(--line); border-radius: 6px; padding: 12px 16px; margin: 12px 0; font-size: 1rem; color: var(--ink-soft); white-space: pre-wrap; }
.q-figure { margin: 14px 0; text-align: center; }
.q-figure svg, .q-figure img { max-width: 100%; height: auto; }

.opts { display: grid; gap: 10px; margin-top: 18px; }
.opt {
  display: flex; align-items: center; gap: 13px; padding: 14px 16px; cursor: pointer;
  background: var(--paper); border: 2px solid var(--line); border-radius: var(--radius-sm);
  font-size: 1.02rem; font-weight: 600; transition: border-color .12s, background .12s;
}
.opt:hover { border-color: var(--acc, var(--coral)); background: var(--paper-2); }
.opt .key { flex: none; width: 30px; height: 30px; border-radius: 8px; display: grid; place-items: center; font-weight: 800; background: var(--line-2); color: var(--ink-soft); }
.opt.sel { border-color: var(--acc, var(--coral)); background: color-mix(in srgb, var(--acc, var(--coral)) 8%, #fff); }
.opt.sel .key { background: var(--acc, var(--coral)); color: #fff; }
.opt.correct { border-color: var(--teal); background: var(--teal-wash); }
.opt.correct .key { background: var(--teal); color: #fff; }
.opt.wrong { border-color: var(--wrong); background: var(--wrong-wash); }
.opt.wrong .key { background: var(--wrong); color: #fff; }
.opt[aria-disabled="true"] { cursor: default; }

.q-explain { margin-top: 16px; padding: 14px 16px; border-radius: var(--radius-sm); background: var(--teal-wash); border: 1px solid #bfe4dc; font-size: .96rem; display: none; }
.q-explain.show { display: block; }
.q-explain b { color: var(--teal); }
.q-explain.bad { background: var(--wrong-wash); border-color: #f2c2cb; }
.q-explain.bad b { color: var(--wrong); }

.exam-nav { display: flex; gap: 12px; margin-top: 22px; align-items: center; }
.exam-nav .spacer { flex: 1; }

/* pantalla de inicio y resultados */
.exam-splash { text-align: center; padding: 30px 0; }
.exam-splash .ico { font-size: 60px; margin-bottom: 10px; }
.exam-splash h1 { font-size: 2rem; margin: 0 0 8px; letter-spacing: -.02em; }
.exam-splash .rules { max-width: 460px; margin: 20px auto; text-align: left; display: grid; gap: 10px; }
.exam-splash .rules li { list-style: none; display: flex; gap: 10px; align-items: flex-start; }
.exam-splash .rules .ck { color: var(--teal); font-weight: 800; }

.score-ring { width: 160px; height: 160px; margin: 6px auto 14px; position: relative; }
.score-ring .num { position: absolute; inset: 0; display: grid; place-items: center; font-size: 2.6rem; font-weight: 800; }
.result-grade { font-size: 1.3rem; font-weight: 800; margin: 4px 0 2px; }
.result-line { color: var(--ink-soft); margin: 0 0 20px; }
.result-breakdown { display: grid; gap: 8px; max-width: 420px; margin: 0 auto 24px; text-align: left; }
.result-breakdown .row { display: flex; align-items: center; gap: 10px; font-weight: 700; }
.result-breakdown .bar { flex: 1; height: 8px; background: var(--line-2); border-radius: 999px; overflow: hidden; }
.result-breakdown .bar i { display: block; height: 100%; background: var(--teal); }

/* ============================================================
   CAJAS DE LECCIÓN (guías de estudio profundas)
   ============================================================ */
.g-box { border-radius: var(--radius-sm); padding: 14px 18px; margin: 14px 0; border: 1px solid; font-size: .97rem; }
.g-box .g-label { display: flex; align-items: center; gap: 8px; font-weight: 800; font-size: .8rem; letter-spacing: .07em; text-transform: uppercase; margin-bottom: 6px; }
.g-box p { margin: 6px 0; }
.g-box ul, .g-box ol { margin: 6px 0; padding-left: 22px; }
.g-box.def  { background: var(--plum-wash);  border-color: #ddd0f2; }
.g-box.def .g-label  { color: var(--plum); }
.g-box.ej   { background: var(--teal-wash);  border-color: #bfe4dc; }
.g-box.ej .g-label   { color: var(--teal); }
.g-box.warn { background: var(--wrong-wash); border-color: #f2c2cb; }
.g-box.warn .g-label { color: var(--wrong); }
.g-box.tip  { background: #fff6e6;           border-color: #f0d79a; }
.g-box.tip .g-label  { color: var(--amber-ink); }

/* figura dentro de una guía */
.g-fig { margin: 16px 0; text-align: center; }
.g-fig svg { max-width: 100%; height: auto; }
.g-fig figcaption { font-size: .86rem; color: var(--muted); margin-top: 6px; line-height: 1.45; }

/* paso a paso de un ejemplo resuelto */
.g-steps { counter-reset: paso; list-style: none; padding-left: 0 !important; }
.g-steps li { counter-increment: paso; position: relative; padding-left: 34px; margin: 8px 0; }
.g-steps li::before { content: counter(paso); position: absolute; left: 0; top: 1px;
  width: 24px; height: 24px; border-radius: 8px; display: grid; place-items: center;
  background: var(--acc, var(--coral)); color: #fff; font-weight: 800; font-size: .8rem; }

/* mini tabla dentro de guías */
.g-table { border-collapse: collapse; margin: 12px auto; font-size: .93rem; }
.g-table th, .g-table td { border: 1px solid var(--line); padding: 6px 12px; text-align: center; }
.g-table th { background: var(--paper); font-weight: 800; }

/* ============================================================
   MAPA DE NIVELES (progresión local, sin usuarios)
   ============================================================ */
.lvl-head { display: flex; align-items: center; gap: 16px; flex-wrap: wrap; margin-bottom: 18px; }
.lvl-head .stars-total { font-weight: 800; font-size: 1.05rem; white-space: nowrap; }
.lvl-head .stars-total .amber { color: var(--amber-ink); }
.lvl-head .bar { flex: 1; min-width: 160px; height: 10px; background: var(--line-2); border-radius: 999px; overflow: hidden; }
.lvl-head .bar i { display: block; height: 100%; background: linear-gradient(90deg, var(--acc, var(--coral)), var(--amber)); border-radius: 999px; transition: width .4s; }

.lvl-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 14px; }
.lvl-card {
  position: relative; display: flex; gap: 13px; align-items: flex-start; cursor: pointer;
  background: var(--paper-2); border: 1px solid var(--line); border-radius: var(--radius-sm);
  padding: 16px; box-shadow: var(--shadow-sm); transition: transform .14s, border-color .14s;
}
.lvl-card:hover { transform: translateY(-2px); border-color: var(--acc, var(--coral)); }
.lvl-num {
  flex: none; width: 40px; height: 40px; border-radius: 12px; display: grid; place-items: center;
  background: var(--acc, var(--coral)); color: #fff; font-weight: 800; font-size: 1.05rem;
}
.lvl-card.done .lvl-num { background: var(--teal); }
.lvl-title { font-weight: 800; font-size: .98rem; line-height: 1.3; margin: 1px 0 5px; }
.lvl-stars { font-size: .95rem; letter-spacing: 2px; color: #ddd3c4; }
.lvl-stars .on { color: var(--amber); }
.lvl-eje { display: inline-block; margin-top: 6px; font-size: .68rem; font-weight: 800; letter-spacing: .07em; text-transform: uppercase; color: var(--plum); background: var(--plum-wash); padding: 2px 9px; border-radius: 999px; }
.lvl-card .next-badge {
  position: absolute; top: -9px; right: 12px; font-size: .66rem; font-weight: 800; letter-spacing: .08em;
  background: var(--amber); color: #5c3c07; padding: 3px 10px; border-radius: 999px; text-transform: uppercase;
  box-shadow: var(--shadow-sm);
}

/* ============================================================
   REPRODUCTOR DE LECCIÓN (leccion.js) — un paso por pantalla
   ============================================================ */
.lx-top { position: sticky; top: 0; z-index: 61; display: flex; align-items: center; gap: 14px;
  background: rgba(251,247,240,.92); backdrop-filter: blur(8px); border-bottom: 1px solid var(--line); padding: 12px 18px; }
.lx-prog { flex: 1; display: flex; gap: 5px; }
.lx-prog i { flex: 1; height: 7px; border-radius: 999px; background: var(--line-2); transition: background .25s; }
.lx-prog i.on { background: var(--acc, var(--coral)); }
.lx-prog i.check { background: var(--line-2); outline: 1.5px dashed #d9cdbb; outline-offset: -1.5px; }
.lx-prog i.check.on { background: var(--amber); outline: none; }
.lx-wrap { max-width: 680px; margin: 0 auto; padding: 26px 20px 60px; }
.lx-kicker { font-size: .74rem; font-weight: 800; letter-spacing: .09em; text-transform: uppercase; color: var(--muted); margin-bottom: 10px; }
.lx-step { animation: lxin .28s ease; }
@keyframes lxin { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: none; } }
.lx-step h4 { font-size: 1.25rem; margin: 0 0 10px; letter-spacing: -.01em; }
.lx-step p { font-size: 1.06rem; line-height: 1.7; }
.lx-step .g-box { font-size: 1.02rem; }
.lx-nav { display: flex; gap: 12px; margin-top: 26px; align-items: center; }
.lx-nav .spacer { flex: 1; }
.lx-check-stem { font-size: 1.15rem; font-weight: 700; line-height: 1.5; margin: 0 0 14px; }
.lx-done { text-align: center; padding: 30px 0; }
.lx-done .big-stars { font-size: 3.2rem; letter-spacing: 8px; color: #ddd3c4; margin: 10px 0 6px; }
.lx-done .big-stars .on { color: var(--amber); animation: pop .4s ease; }
@keyframes pop { from { transform: scale(.3); } 60% { transform: scale(1.25); } to { transform: scale(1); } }
.lx-done h2 { margin: 4px 0 6px; }
.lx-done p { color: var(--ink-soft); }

/* utilidades */
.center { text-align: center; }
.hidden { display: none !important; }
.mt { margin-top: 20px; }
.tag { display: inline-block; font-size: .74rem; font-weight: 800; padding: 3px 10px; border-radius: 999px; background: var(--plum-wash); color: var(--plum); }

@media (max-width: 640px) {
  .actions { grid-template-columns: 1fr; }
  .exam-bar { top: 60px; }
  .hero { padding: 32px 0 20px; }
}