/* ===== Compás — identidad visual del sitio ===== */
:root {
  --cream: #f6f3ea;
  --forest: #14301f;
  --forest-soft: #1c3d28;
  --moss: #3f6b4a;
  --lime: #c4e86b;
  --ink: #22301f;
  --ink-soft: #56604f;
  --line: rgba(63, 107, 74, 0.25);
  --surface: #ffffff;
  --callout-bg: #e4f1d3;
  --callout-border: #c3dba3;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--cream);
  color: var(--ink);
  font-family: 'Karla', system-ui, sans-serif;
  line-height: 1.6;
}

h1, h2, h3 {
  font-family: 'Outfit', system-ui, sans-serif;
  font-weight: 600;
  text-wrap: balance;
  margin: 0;
}

a { color: inherit; }

.wrap {
  max-width: 1040px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ---- Nav ---- */
.site-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.1rem 1.5rem;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 0.95rem;
  text-decoration: none;
  color: var(--ink);
}
.brand .mark {
  width: 0; height: 0;
  border-left: 9px solid transparent;
  border-right: 9px solid transparent;
  border-bottom: 15px solid var(--forest);
}
.site-nav .back {
  font-size: 0.85rem;
  color: var(--moss);
  text-decoration: none;
  font-weight: 600;
}
.site-nav .back:hover { color: var(--forest); }

/* ---- Hero (home) ---- */
.hero {
  width: min(100% - 3rem, 1040px);
  margin: 0 auto 2.2rem auto;
  padding: 3rem 2.2rem;
  border-radius: 20px;
  background: var(--forest);
  color: var(--cream);
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute; right: -60px; top: -80px;
  width: 280px; height: 280px; border-radius: 50%;
  border: 2px solid rgba(196,232,107,0.25);
}
.hero::after {
  content: "";
  position: absolute; right: 60px; bottom: -70px;
  width: 160px; height: 160px;
  border: 2px solid rgba(246,243,234,0.18);
  transform: rotate(20deg);
}
.hero .eyebrow {
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--lime);
  position: relative;
}
.hero h1 {
  font-size: clamp(1.8rem, 4vw, 2.7rem);
  margin: 0.6rem 0 0.9rem;
  max-width: 18ch;
  position: relative;
}
.hero p {
  max-width: 42ch;
  opacity: 0.88;
  position: relative;
  margin: 0;
}

/* ---- Course grid ---- */
/* Subtítulos de sección: título con línea lima debajo (que no se pierdan en el texto) */
.section-label {
  font-family: 'Outfit', 'Karla', system-ui, sans-serif;
  font-size: clamp(1.2rem, 3.4vw, 1.5rem);
  font-weight: 600;
  line-height: 1.25;
  text-transform: none;
  color: var(--forest);
  width: min(100% - 3rem, 760px);
  margin: 2.2rem auto 1.1rem auto;
  padding-bottom: 0.4rem;
  border-bottom: 3px solid var(--lime);
  scroll-margin-top: 1rem;
}
.courses {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.1rem;
  width: min(100% - 3rem, 1040px);
  margin: 0 auto 2.5rem auto;
}
@media (min-width: 640px) {
  .courses { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 900px) {
  .courses { grid-template-columns: repeat(3, 1fr); }
}
.course-card {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 20px 6px 20px 6px;
  padding: 1.4rem 1.4rem 1.5rem;
  text-decoration: none;
  color: var(--ink);
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  transition: transform 0.15s ease, border-color 0.15s ease;
}
.badge-proximamente {
  position: absolute;
  top: 1.1rem;
  right: 1.1rem;
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.62rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--moss);
  background: var(--cream);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.2rem 0.6rem;
}
.course-card:hover {
  transform: translateY(-3px);
  border-color: var(--moss);
}
.course-card .num {
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.7rem;
  color: var(--moss);
}
.course-card h3 { font-size: 1.15rem; }
.course-card p {
  font-size: 0.85rem;
  color: var(--ink-soft);
  margin: 0;
  flex: 1;
}
.course-card .go {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--forest);
}
.course-card .ico {
  width: 22px; height: 22px;
  background: var(--moss);
  border-radius: 50%;
}
.course-card.optativa .ico {
  border-radius: 4px;
  transform: rotate(45deg);
}

footer.site-footer {
  padding: 2rem 1.5rem 3rem;
  text-align: center;
  color: var(--ink-soft);
  font-size: 0.82rem;
}

/* ---- Course page ---- */
.course-header {
  width: min(100% - 3rem, 1040px);
  margin: 0 auto 2rem auto;
  padding: 2.2rem 2rem;
  border-radius: 20px;
  background: var(--surface);
  border: 1px solid var(--line);
}
.course-header .k {
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--moss);
}
.course-header h1 {
  font-size: clamp(1.6rem, 3.5vw, 2.2rem);
  margin: 0.5rem 0 0;
}

.blocks {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
  width: min(100% - 3rem, 760px);
  margin: 0 auto 3rem auto;
}
@media (min-width: 560px) {
  .blocks { grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }
}
.block {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 1.3rem 1.3rem 1.4rem;
}
.block h2 { font-size: 1rem; margin-bottom: 0.5rem; }
.block p { font-size: 0.85rem; color: var(--ink-soft); margin: 0; }

/* ---- Contenido de un tema (prosa, ejemplos, métodos) ---- */
.prose {
  width: min(100% - 3rem, 68ch);
  margin: 0 auto 2.2rem auto;
  font-size: 0.95rem;
  line-height: 1.75;
  color: var(--ink);
}
.prose p { margin: 0 0 1rem; }
.prose p:last-child { margin-bottom: 0; }
.prose strong { color: var(--forest); }

/* ---- Video incrustado ---- */
.video-embed {
  position: relative;
  width: min(100% - 3rem, 640px);
  aspect-ratio: 16 / 9;
  margin: 0 auto 0.8rem auto;
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--forest);
}
.video-embed iframe,
.video-embed video {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
}
.video-embed-caption {
  width: min(100% - 3rem, 640px);
  margin: 0 auto 1.6rem auto;
  font-size: 0.85rem;
  color: var(--ink-soft);
  text-align: center;
}

.example-box {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 1.4rem 1.5rem 1.6rem;
  width: min(100% - 3rem, 760px);
  margin: 0 auto 2.5rem auto;
}
.example-box h2 {
  font-size: 1.02rem;
  margin: 0 0 0.6rem;
}
.example-box p {
  font-size: 0.9rem;
  color: var(--ink-soft);
  margin: 0 0 1rem;
  line-height: 1.6;
}
.example-box .eq {
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 1.05rem;
  background: var(--cream);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0.55rem 1rem;
  display: inline-block;
  margin: 0 0.6rem 0.5rem 0;
}
/* Fragmento de una fórmula compuesta (texto + determinante/fracción + texto):
   mismo estilo tipográfico que .eq, pero sin la "pastilla" con borde, para que
   toda la fórmula se lea como una sola pieza en vez de varios cuadros sueltos. */
.example-box .eq-plain {
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 1.05rem;
  color: var(--ink);
}

.method-list {
  width: min(100% - 3rem, 60ch);
  margin: 0 auto 2.5rem auto;
  padding-left: 1.3rem;
}
.method-list li {
  margin-bottom: 0.45rem;
  color: var(--ink-soft);
  font-size: 0.92rem;
}
.method-list strong { color: var(--ink); }

/* ---- Bloques adicionales para páginas de subtema (objetivo, casos, pasos, gráficas) ---- */
.callout {
  width: min(100% - 3rem, 760px);
  margin: 0 auto 2.2rem auto;
  padding: 1.2rem 1.4rem;
  background: var(--callout-bg);
  border: 1px solid var(--callout-border);
  color: var(--forest);
  border-radius: 14px;
}
.callout .k {
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--moss);
}
.callout p { margin: 0.4rem 0 0; font-size: 0.92rem; line-height: 1.6; opacity: 0.92; }

.case-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
  width: min(100% - 3rem, 760px);
  margin: 0 auto 2.5rem auto;
}
@media (min-width: 480px) {
  .case-grid { grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); }
}
.case-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 1rem 1rem 1.2rem;
  text-align: center;
}
.case-card svg { display: block; margin: 0 auto 0.6rem; }
.case-card h3 { font-size: 0.9rem; margin-bottom: 0.3rem; }
.case-card p { font-size: 0.78rem; color: var(--ink-soft); margin: 0; }

.steps {
  list-style: none;
  counter-reset: step;
  width: min(100% - 3rem, 760px);
  margin: 0 auto 2.2rem auto;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.7rem;
}
.steps li {
  counter-increment: step;
  display: flex;
  gap: 0.9rem;
  align-items: baseline;
  font-size: 0.9rem;
  color: var(--ink-soft);
  line-height: 1.6;
}
.steps li::before {
  content: counter(step);
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.78rem;
  color: var(--cream);
  background: var(--moss);
  border-radius: 50%;
  width: 1.5rem; height: 1.5rem;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
}
.steps strong { color: var(--ink); }

.graph-figure {
  width: min(100% - 3rem, 760px);
  margin: 0 auto 2.2rem auto;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 1.2rem;
  text-align: center;
}
.graph-figure svg { max-width: 100%; height: auto; }
.graph-figure figcaption {
  margin-top: 0.6rem;
  font-size: 0.8rem;
  color: var(--ink-soft);
}

/* ---- Determinantes (método de Cramer) ---- */
.det {
  display: inline-flex;
  align-items: stretch;
  vertical-align: middle;
  margin: 0 0.3rem 0.3rem 0;
}
.det-bar {
  width: 1px;
  background: var(--ink);
  margin: 0.1rem 0.55rem;
}
.det-grid {
  display: grid;
  grid-template-columns: auto auto;
  gap: 0.2rem 0.9rem;
  align-content: center;
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.95rem;
  text-align: right;
  padding: 0.15rem 0;
}
/* ---- Fracciones (numerador sobre denominador, sin diagonal) ---- */
.frac {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  vertical-align: middle;
  margin: 0 0.25rem;
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.95rem;
  line-height: 1.3;
}
.frac .num { padding-bottom: 0.15rem; text-align: center; }
.frac .den { border-top: 1.5px solid var(--ink); padding-top: 0.15rem; align-self: stretch; text-align: center; } /* la raya cubre todo el numerador */
.frac.frac-inline { font-size: 0.85rem; margin: 0 0.2rem; }

/* ---- Ejercicios ---- */
.exercise-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.9rem;
  width: min(100% - 3rem, 760px);
  margin: 0 auto 2.5rem auto;
}
@media (min-width: 480px) {
  .exercise-grid { grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); }
}
.exercise-card {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 0.9rem 1rem;
}
.exercise-card .enum {
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.78rem;
  color: var(--cream);
  background: var(--moss);
  border-radius: 50%;
  width: 1.7rem; height: 1.7rem;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
}
.exercise-card .eqs {
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.82rem;
  color: var(--ink);
  line-height: 1.6;
}

/* ---- Tabla ancha (rúbrica) ---- */
.table-scroll {
  overflow-x: auto;
  width: min(100% - 3rem, 760px);
  margin: 0 auto 2.5rem auto;
  border: 1px solid var(--line);
  border-radius: 14px;
}
.table-scroll table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.8rem;
  min-width: 720px;
}
.table-scroll th, .table-scroll td {
  border: 1px solid var(--line);
  padding: 0.65rem 0.8rem;
  text-align: left;
  vertical-align: top;
  line-height: 1.5;
}
.table-scroll th {
  background: var(--forest);
  color: var(--cream);
  font-family: 'Outfit', sans-serif;
  font-weight: 600;
  font-size: 0.78rem;
}
.table-scroll td:first-child { font-weight: 700; background: var(--cream); }

/* ---- Temario (lista de temas de una materia) ---- */
.tema-list {
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
  width: min(100% - 3rem, 1040px);
  margin: 0 auto 3rem auto;
}
.tema-row {
  display: flex;
  align-items: flex-start;
  gap: 1.1rem;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 16px 6px 16px 6px;
  padding: 1.1rem 1.3rem;
  text-decoration: none;
  color: var(--ink);
  transition: transform 0.15s ease, border-color 0.15s ease;
}
.tema-row:hover {
  transform: translateY(-2px);
  border-color: var(--moss);
}
.tema-row .tnum {
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.85rem;
  color: var(--moss);
  min-width: 2.2rem;
  padding-top: 0.15rem;
}
.tema-row .tbody { flex: 1; display: flex; flex-direction: column; gap: 0.5rem; }
.tema-row h3 { font-size: 1.05rem; }
.tema-row .subtemas {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}
.tema-row .subtemas span {
  font-size: 0.72rem;
  color: var(--ink-soft);
  background: var(--cream);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.15rem 0.6rem;
}
.tema-row .go {
  align-self: center;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--forest);
  white-space: nowrap;
}

/* ---- Gráfica interactiva (pendiente y ordenada) ---- */
.pg-equation {
  text-align: center;
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 1.15rem;
  color: var(--forest);
  margin: 0 0 1rem;
}
.pg-label {
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 11px;
  fill: var(--forest);
  font-weight: 600;
}
.pg-label.small { font-size: 9.5px; fill: var(--moss); font-weight: 500; }
.pg-point { fill: var(--lime); stroke: var(--forest); stroke-width: 1.5; }
.pg-guide { stroke: var(--moss); stroke-width: 2; fill: none; }
.pg-final-line { stroke: var(--forest); stroke-width: 2.6; fill: none; }
.pg-scale-note {
  text-align: center;
  font-size: 0.75rem;
  color: var(--moss);
  font-weight: 600;
  margin: -0.4rem 0 1rem;
  min-height: 1em;
}

.pg-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 1.4rem;
  justify-content: center;
  margin: 1rem 0 1.2rem;
}
.pg-field {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.35rem;
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.68rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--moss);
}
.pg-field input[type="range"] { width: 110px; accent-color: var(--moss); }
.pg-field .val {
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.95rem;
  color: var(--forest);
  font-weight: 700;
  text-transform: none;
}
.pg-field-label {
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.68rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--moss);
}
.pg-field-row { display: flex; align-items: center; gap: 0.5rem; }
/* Etiquetas con fórmulas o letras matemáticas: se muestran tal cual (sin mayúsculas) */
.section-label.no-caps, .callout .k.no-caps, .pg-field-label.no-caps { text-transform: none; }
.pg-box {
  width: 52px;
  text-align: center;
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--forest);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0.3rem 0.35rem;
}
.pg-box.wide { width: 68px; }
.pg-box:focus { outline: 2px solid var(--moss); outline-offset: 1px; }
.pg-box.invalid { border-color: #c0392b; }
.pg-actions {
  display: flex;
  gap: 0.8rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 0.4rem;
}
.pg-btn {
  font-family: 'Outfit', sans-serif;
  font-weight: 600;
  font-size: 0.85rem;
  color: var(--cream);
  background: var(--forest);
  border: none;
  border-radius: 999px;
  padding: 0.6rem 1.3rem;
  cursor: pointer;
  transition: background 0.15s ease;
}
.pg-btn:hover { background: var(--forest-soft); }
.pg-btn:disabled { opacity: 0.6; cursor: default; }
.pg-btn.secondary {
  background: var(--cream);
  color: var(--forest);
  border: 1px solid var(--line);
}
.pg-btn.secondary:hover { border-color: var(--moss); }

.steps li.active { color: var(--forest); font-weight: 600; }
.steps li.active::before { background: var(--lime); color: var(--forest); }

@media (max-width: 640px) {
  .hero { padding: 2.2rem 1.4rem; }
  .site-nav { padding: 1rem; }
  .tema-row { flex-wrap: wrap; }
  .tema-row .go { align-self: flex-start; }
}

/* ---- Funciones: diagramas sagitales, gráficas pequeñas y clasificación ---- */
.sagital-grid, .mini-graph-grid {
  display: grid;
  gap: 0.9rem;
  width: min(100% - 3rem, 760px);
  margin: 0 auto 1.6rem auto;
}
.sagital-grid { grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }
.mini-graph-grid { grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); margin-bottom: 2.5rem; }
.sagital-card, .mini-graph {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 0.6rem;
  text-align: center;
  margin: 0;
}
.sagital-card svg, .mini-graph svg { max-width: 100%; height: auto; }
.mini-graph figcaption {
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.78rem;
  color: var(--ink-soft);
}
.fill-table td { height: 2.6rem; }
.def-list, .class-tree { margin: 0; padding-left: 1.2rem; font-size: 0.92rem; line-height: 1.8; }
.class-tree ul { padding-left: 1.3rem; }
.class-tree mark { background: var(--lime); color: var(--forest); border-radius: 4px; padding: 0 0.3rem; font-weight: 700; }

/* ---- Rúbricas desplegables ---- */
details.rubric {
  width: min(100% - 3rem, 760px);
  margin: 0 auto 2.5rem auto;
}
details.rubric summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 0.6rem;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 0.8rem 1rem;
  font-weight: 700;
  color: var(--forest);
}
details.rubric summary::-webkit-details-marker { display: none; }
details.rubric summary::before {
  content: "+";
  display: inline-flex; align-items: center; justify-content: center;
  width: 1.5rem; height: 1.5rem; flex-shrink: 0;
  border-radius: 50%;
  background: var(--lime);
  color: var(--forest);
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
}
details.rubric[open] summary { margin-bottom: 0.8rem; }
details.rubric[open] summary::before { content: "−"; }
details.rubric .table-scroll { width: 100%; margin: 0; }

/* Rúbrica por niveles (matriz de criterios: Niveles 1 a 5 y Nivel 0) */
details.rubric.rubric-matriz { width: min(100% - 3rem, 1040px); }
.rubric-matriz table.matriz { min-width: 980px; }
.rubric-matriz table.matriz th { vertical-align: bottom; }
.rubric-matriz table.matriz th small {
  display: block;
  margin-top: 0.15rem;
  font-family: 'Karla', system-ui, sans-serif;
  font-weight: 400;
  font-size: 0.7rem;
  opacity: 0.85;
}
.rubric-matriz table.matriz td.crit { min-width: 14rem; font-weight: 400; }
.rubric-matriz table.matriz td.crit > strong { display: block; color: var(--forest); }
.rubric-matriz table.matriz td.crit .sub,
.rubric-matriz table.matriz td.crit .crit-desc {
  display: block;
  margin-top: 0.15rem;
  font-size: 0.72rem;
  color: var(--ink-soft);
}
.rubric-matriz table.matriz td.crit .en-act {
  display: block;
  margin-top: 0.5rem;
  padding: 0.4rem 0.5rem;
  background: var(--callout-bg);
  border: 1px solid var(--callout-border);
  border-radius: 8px;
  font-size: 0.74rem;
  color: var(--forest);
}
.rubric-matriz table.matriz td.crit .en-act strong { display: inline; }
.rubric-matriz table.matriz td.crit .en-act ul { margin: 0.3rem 0 0; padding-left: 1.05rem; }
.rubric-matriz table.matriz td.crit .en-act li { margin: 0 0 0.25rem; }
.rubric-matriz .rubric-note {
  margin: 0.8rem 0 0;
  padding: 0.7rem 0.9rem;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 10px;
  font-size: 0.82rem;
  color: var(--ink-soft);
}

/* ---- Títulos grandes de cada tarea ---- */
.task-title {
  width: min(100% - 3rem, 760px);
  margin: 0.5rem auto 1.2rem auto;
  padding-bottom: 0.5rem;
  border-bottom: 3px solid var(--lime);
  font-size: clamp(1.4rem, 4vw, 1.9rem);
  color: var(--forest);
  scroll-margin-top: 1rem;
}
.task-subtitle {
  width: min(100% - 3rem, 760px);
  margin: 0 auto 0.8rem auto;
  font-size: 1.25rem;
  color: var(--moss);
}

/* ---- Respuestas desplegables en los ejercicios ---- */
.exercise-card.has-answer { flex-wrap: wrap; align-items: flex-start; }
.exercise-card.has-answer .enum { margin-top: 0.15rem; }
.exercise-card details.answer { flex-basis: 100%; }
.exercise-card details.answer summary {
  cursor: pointer;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--moss);
}
.exercise-card details.answer[open] summary { margin-bottom: 0.5rem; }
.exercise-card details.answer p { font-size: 0.8rem; margin: 0 0 0.4rem; line-height: 1.45; }
.exercise-card details.answer .answer-lines { font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.72rem; }
.exercise-card details.answer .answer-lines span { display: block; }
.exercise-card details.answer .answer-lines .l1 { color: var(--forest); }
.exercise-card details.answer .answer-lines .l2 { color: #b5452f; }
.exercise-card details.answer svg { width: 100%; max-width: 220px; height: auto; display: block; margin: 0 auto; }
.exercise-card.has-answer { align-self: start; }
.exercise-card details.answer .answer-dets { font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.74rem; }
.exercise-card details.answer .answer-dets span, .exercise-card details.answer .nw { white-space: nowrap; }
.exercise-card details.answer .answer-dets span { margin-right: 0.6rem; }
.exercise-card details.answer .answer-calc { font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.78rem; line-height: 2.4; }
.table-scroll td.ans { font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.85rem; white-space: nowrap; color: var(--forest); }
details.rubric .interval-answer { width: 100%; margin: 0 0 0.8rem; padding: 1rem 1.2rem; }
details.rubric .interval-answer p { margin: 0 0 0.5rem; }
details.rubric .interval-answer svg { display: block; max-width: 100%; height: auto; margin-top: 0.6rem; }
details.rubric .interval-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 0.8rem; margin-bottom: 0.8rem; }
details.rubric .interval-card { background: var(--surface); border: 1px solid var(--line); border-radius: 12px; padding: 0.8rem 0.9rem; }
details.rubric .interval-card p { margin: 0 0 0.5rem; font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.82rem; display: flex; align-items: center; gap: 0.5rem; flex-wrap: wrap; }
details.rubric .interval-card .enum { font-size: 0.72rem; color: var(--cream); background: var(--moss); border-radius: 50%; width: 1.5rem; height: 1.5rem; display: inline-flex; align-items: center; justify-content: center; flex-shrink: 0; }
details.rubric .interval-card .eq { font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.95rem; background: var(--cream); border: 1px solid var(--line); border-radius: 8px; padding: 0.3rem 0.8rem; display: inline-block; }
details.rubric .interval-card svg { display: block; width: 100%; max-width: 260px; height: auto; margin-top: 0.4rem; }
.exercise-card details.answer .answer-interval { font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.9rem; white-space: nowrap; }
.exercise-card details.answer svg[viewBox="0 0 260 72"] { max-width: 260px; }

/* ---- Ejercicios con revisión automática ---- */
.practice-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.9rem;
  width: min(100% - 3rem, 760px);
  margin: 0 auto 1.2rem auto;
}
@media (min-width: 620px) {
  .practice-grid { grid-template-columns: 1fr 1fr; }
}
.practice-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 0.9rem 1rem 1rem;
  transition: border-color 0.2s, background 0.2s;
}
.practice-card.ok { border-color: #6fa35a; background: #f3faea; }
.practice-card.bad { border-color: #d48a78; }
.practice-head { display: flex; align-items: center; gap: 0.7rem; margin-bottom: 0.6rem; }
.practice-head .enum {
  font-family: 'IBM Plex Mono', ui-monospace, monospace;
  font-size: 0.78rem; color: var(--cream); background: var(--moss);
  border-radius: 50%; width: 1.7rem; height: 1.7rem;
  display: flex; align-items: center; justify-content: center; flex-shrink: 0;
}
.practice-card.ok .enum { background: #4f8a3c; }
.practice-q { font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.98rem; color: var(--forest); font-weight: 500; }
.practice-q .frac.frac-inline { font-size: 0.78rem; }
.practice-row { display: flex; gap: 0.5rem; align-items: center; flex-wrap: wrap; }
.practice-row .eq { font-family: 'IBM Plex Mono', ui-monospace, monospace; font-weight: 700; color: var(--forest); }
.practice-row input {
  flex: 1 1 140px; min-width: 0;
  font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.95rem;
  padding: 0.45rem 0.6rem; border: 1.5px solid var(--line); border-radius: 8px;
  background: #fff; color: var(--ink);
}
.practice-row input:focus { outline: 2px solid var(--moss); outline-offset: 1px; }
.practice-keys { display: flex; gap: 0.3rem; margin-top: 0.45rem; flex-wrap: wrap; }
.practice-keys button {
  font-family: 'Karla', system-ui, sans-serif; font-size: 1.25rem; font-weight: 700; line-height: 1;
  border: 1px solid var(--line); background: var(--cream); color: var(--forest);
  border-radius: 6px; min-width: 2.2rem; height: 2rem; padding: 0 0.5rem; cursor: pointer;
}
.practice-check {
  font-family: 'Outfit', system-ui, sans-serif; font-weight: 600; font-size: 0.85rem;
  background: var(--forest); color: var(--cream); border: 0; border-radius: 8px;
  padding: 0.5rem 0.9rem; cursor: pointer;
}
.practice-check:hover { background: var(--forest-soft); }
.practice-fb { font-size: 0.86rem; margin-top: 0.55rem; line-height: 1.5; min-height: 0; }
.practice-fb .yes { color: #3d7a2c; font-weight: 700; }
.practice-fb .no { color: #b3412e; font-weight: 700; }
.practice-fb .show {
  background: none; border: 0; padding: 0; margin-left: 0.2rem; cursor: pointer;
  color: var(--moss); font-weight: 700; text-decoration: underline; font-size: 0.86rem;
}
.practice-fb .sol { font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.82rem; color: var(--forest); margin-top: 0.3rem; line-height: 1.8; }
.practice-score {
  width: min(100% - 3rem, 760px); margin: 0 auto 2.5rem auto; text-align: center;
  font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.85rem; color: var(--moss);
}
.practice-score strong { color: var(--forest); font-size: 1rem; }
/* Ejercicios de opción (botones para elegir una respuesta) */
.practice-ask { font-size: 0.86rem; font-weight: 700; color: var(--forest); margin: 0.55rem 0 0.3rem; }
.practice-opts { display: flex; gap: 0.35rem; flex-wrap: wrap; }
.practice-opts button {
  font-family: 'Karla', system-ui, sans-serif; font-size: 0.85rem;
  border: 2px solid var(--line); background: var(--surface); color: var(--ink-soft);
  border-radius: 999px; padding: 0.3rem 0.8rem; cursor: pointer;
  transition: background 0.15s, border-color 0.15s, opacity 0.15s;
}
.practice-opts button::before { content: '○ '; }
.practice-opts button:hover { border-color: var(--moss); color: var(--forest); }
/* La opción elegida: fondo verde-lima, borde oscuro y palomita */
.practice-opts button.on {
  background: var(--lime); border-color: var(--forest); color: var(--forest);
  font-weight: 700; box-shadow: 0 2px 6px rgba(20, 48, 31, 0.25);
}
.practice-opts button.on::before { content: '✓ '; }
/* Cuando ya se eligió una, las demás se ven más tenues */
.practice-opts:has(button.on) button:not(.on) { opacity: 0.55; }
.practice-opts:has(button.on) button:not(.on):hover { opacity: 1; }
/* Raíz cuadrada con barra (vínculo) que cubre todo el radicando */
.rad { white-space: nowrap; }
.radicand { border-top: 0.08em solid currentColor; padding: 0.08em 0.12em 0 0.14em; margin-left: -0.08em; }

/* ===== Regla destacada: cuadro grande con la fórmula y sus pasos de colores ===== */
.regla-box { width: min(100% - 3rem, 760px); margin: 1.6rem auto 2.4rem auto; border: 3px solid var(--forest); border-radius: 22px; overflow: hidden; background: var(--surface); box-shadow: 0 7px 0 var(--forest); }
.regla-head { background: var(--forest); color: var(--lime); font-family: 'Outfit', system-ui, sans-serif; font-weight: 600; letter-spacing: 0.16em; text-transform: uppercase; text-align: center; font-size: 1.05rem; padding: 0.55rem 1rem; }
.regla-formula { background: var(--lime); color: var(--forest); text-align: center; font-family: 'IBM Plex Mono', ui-monospace, monospace; font-weight: 500; font-size: clamp(1.1rem, 4.6vw, 2rem); line-height: 1.9; padding: 1rem 0.8rem; }
.regla-formula .ig { opacity: 0.8; }
.regla-chip { display: inline-block; padding: 0 0.4em; border-radius: 0.4em; color: #fff; font-weight: 700; line-height: 1.5; }
.regla-chip.c1 { background: var(--forest); }
.regla-chip.c2 { background: #d9650b; }
.regla-chip.c3 { background: #2b6cb0; }
.regla-steps { display: grid; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); gap: 0.9rem; padding: 1.1rem; }
.regla-step { border: 3px solid; border-radius: 16px; padding: 0.8rem 0.9rem 1rem; text-align: center; position: relative; background: #fff; }
.regla-step.c1 { border-color: var(--forest); }
.regla-step.c2 { border-color: #d9650b; }
.regla-step.c3 { border-color: #2b6cb0; }
.regla-step .n { width: 2rem; height: 2rem; border-radius: 50%; color: #fff; font-family: 'Outfit', system-ui, sans-serif; font-weight: 600; display: inline-flex; align-items: center; justify-content: center; font-size: 1.1rem; }
.regla-step.c1 .n { background: var(--forest); }
.regla-step.c2 .n { background: #d9650b; }
.regla-step.c3 .n { background: #2b6cb0; }
.regla-step .big { font-family: 'Outfit', system-ui, sans-serif; font-weight: 600; font-size: 1.9rem; line-height: 1.2; margin: 0.3rem 0 0.2rem; }
.regla-step.c1 .big { color: var(--forest); }
.regla-step.c2 .big { color: #d9650b; }
.regla-step.c3 .big { color: #2b6cb0; }
.regla-step .txt { font-size: 1.02rem; line-height: 1.4; color: var(--ink); }
.regla-ejemplo { margin: 0 1.1rem 1.1rem; border-radius: 14px; background: var(--callout-bg); border: 2px dashed var(--moss); padding: 0.8rem 1rem; text-align: center; font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: clamp(0.95rem, 3.6vw, 1.2rem); line-height: 2; color: var(--forest); }
.regla-ejemplo .lbl { display: block; font-family: 'Karla', system-ui, sans-serif; font-size: 0.85rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--moss); font-weight: 700; }
.regla-signos { margin: 0 1.1rem 1.2rem; text-align: center; font-size: 1.02rem; }
.regla-pill { display: inline-block; margin: 0.2rem 0.25rem; padding: 0.2rem 0.8rem; border-radius: 999px; background: var(--forest); color: #fff; font-weight: 700; }
.regla-pill.neg { background: #fff; color: var(--forest); border: 2px solid var(--forest); }
/* Regla simple: "Paso 1, Paso 2, Paso 3" con la expresión grande y una sola palabra */
.regla-step .paso { display: inline-block; padding: 0.12rem 1rem; border-radius: 999px; color: #fff; font-family: 'Outfit', system-ui, sans-serif; font-weight: 600; letter-spacing: 0.1em; text-transform: uppercase; font-size: 0.95rem; }
.regla-step.c1 .paso { background: var(--forest); }
.regla-step.c2 .paso { background: #d9650b; }
.regla-step.c3 .paso { background: #2b6cb0; }
.regla-step .big { font-family: 'IBM Plex Mono', ui-monospace, monospace; font-weight: 500; font-size: clamp(1.25rem, 5.4vw, 2.2rem); margin: 0.5rem 0 0.1rem; }
.regla-step .txt { font-size: 1rem; color: var(--ink-soft); text-transform: uppercase; letter-spacing: 0.08em; font-weight: 700; }
.regla-signos { margin-top: -0.2rem; }
/* etiquetas de color con fracciones adentro: más espacio y raya del mismo color que el texto */
.regla-ejemplo { line-height: 2.7; }
.regla-chip { vertical-align: middle; margin: 0.15em 0; }
.regla-chip .frac { vertical-align: middle; margin: 0 0.1rem; }
.regla-chip .frac .den { border-top-color: currentColor; }

/* ===== Recordatorio de las leyes de los signos ===== */
.signos-box { width: min(100% - 3rem, 760px); margin: 0 auto 2.4rem auto; border: 2px solid var(--forest); border-radius: 18px; background: var(--surface); overflow: hidden; }
.signos-head { background: var(--forest); color: var(--lime); font-family: 'Outfit', system-ui, sans-serif; font-weight: 600; letter-spacing: 0.1em; text-transform: uppercase; font-size: 0.95rem; text-align: center; padding: 0.5rem 1rem; }
.signos-cols { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 1rem; padding: 1rem 1.1rem 0.6rem; }
.signos-t { font-family: 'Outfit', system-ui, sans-serif; font-weight: 600; font-size: 1.15rem; color: var(--forest); margin-bottom: 0.4rem; }
.signos-row { display: flex; justify-content: space-between; align-items: center; gap: 0.6rem; padding: 0.3rem 0.7rem; margin-bottom: 0.3rem; border-radius: 10px; background: var(--callout-bg); font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.95rem; color: var(--forest); }
.signos-row b { font-family: 'Outfit', system-ui, sans-serif; font-size: 1.4rem; line-height: 1; min-width: 1.4rem; text-align: center; }
.signos-row.pos b { color: #2b6cb0; }
.signos-row.neg b { color: #d9650b; }
.signos-row.txt { display: block; font-family: 'Karla', system-ui, sans-serif; font-size: 1rem; }
.signos-ej { font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.9rem; color: var(--ink-soft); margin: 0.2rem 0 0.6rem 0.2rem; }
.signos-link { text-align: center; padding: 0.2rem 1rem 0.9rem; font-size: 0.95rem; }
.signos-link a { color: var(--forest); font-weight: 700; }

/* ===== Barras de fracciones (para ver la suma de fracciones) ===== */
.fbarras { width: min(100% - 3rem, 760px); margin: 0 auto 2rem auto; }
.fbar-row { display: flex; align-items: center; gap: 0.9rem; margin: 0.55rem 0; }
.fbar-lbl { width: 5.2rem; text-align: right; font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 1rem; color: var(--forest); white-space: nowrap; }
.fbar { display: flex; flex: 1; max-width: 380px; border: 2px solid var(--forest); border-radius: 8px; overflow: hidden; background: #fff; }
.fbar span { flex: 1; height: 30px; border-right: 1.5px solid var(--forest); }
.fbar span:last-child { border-right: 0; }
.fbar span.a { background: var(--lime); }
.fbar span.b { background: #f1b27a; }
.fbar-cap { text-align: center; font-size: 0.9rem; color: var(--ink-soft); margin-top: 0.4rem; }
/* frases dentro del recuadro de ejemplo, y fracciones más grandes en la fórmula de la regla */
.regla-ejemplo .nota { font-family: 'Karla', system-ui, sans-serif; font-size: 1rem; line-height: 1.6; display: inline-block; }
.regla-formula .frac.frac-inline { font-size: 0.85em; }

/* ===== Descomposición en primos: escalera de divisiones y tabla de exponentes ===== */
.escalera { border-collapse: collapse; margin: 0.4rem auto 1rem; font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 1.1rem; color: var(--forest); }
.escalera td { padding: 0.12rem 0.9rem; }
.escalera td:first-child { text-align: right; border-right: 3px solid var(--forest); }
.escalera td:last-child { color: #d9650b; font-weight: 700; }
.exp-wrap { width: min(100% - 3rem, 760px); margin: 0 auto 1.6rem auto; overflow-x: auto; }
.exp-table { border-collapse: separate; border-spacing: 5px; margin: 0.4rem auto; font-family: 'IBM Plex Mono', ui-monospace, monospace; text-align: center; font-size: 1rem; }
.exp-table th, .exp-table td { padding: 0.4rem 1rem; border-radius: 9px; background: var(--callout-bg); color: var(--forest); }
.exp-table th { background: var(--forest); color: var(--lime); font-weight: 500; }
.exp-table td.lbl { background: transparent; text-align: left; font-weight: 700; white-space: nowrap; }
.exp-table td.min { background: #2b6cb0; color: #fff; font-weight: 700; }
.exp-table td.max { background: #d9650b; color: #fff; font-weight: 700; }
.exp-cap { text-align: center; font-size: 0.9rem; color: var(--ink-soft); }
@media (max-width: 480px) {
  .exp-table { font-size: 0.85rem; border-spacing: 3px; }
  .exp-table th, .exp-table td { padding: 0.3rem 0.5rem; }
}

/* ===== Criba de Eratóstenes (1 a 100) y tablas de criterios ===== */
.criba { display: grid; grid-template-columns: repeat(10, 1fr); gap: 3px; width: min(100% - 3rem, 440px); margin: 0.6rem auto 0.4rem; font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.85rem; }
.criba span { text-align: center; padding: 0.3rem 0; border-radius: 6px; background: var(--callout-bg); color: var(--ink-soft); }
.criba span.p { background: var(--lime); color: var(--forest); font-weight: 700; }
.criba span.u { background: #d9d6c9; color: #6b6b60; }
.crit-table { width: min(100% - 3rem, 760px); margin: 0.4rem auto 1.4rem; border-collapse: separate; border-spacing: 0 6px; font-size: 0.98rem; }
.crit-table td { padding: 0.55rem 0.8rem; background: var(--callout-bg); }
.crit-table td:first-child { background: var(--forest); color: var(--lime); font-family: 'Outfit', system-ui, sans-serif; font-weight: 600; font-size: 1.15rem; text-align: center; width: 4.5rem; border-radius: 10px 0 0 10px; }
.crit-table td:last-child { border-radius: 0 10px 10px 0; font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.88rem; color: var(--forest); }

/* ===== Tabla de descomposición simultánea (mcm y MCD) ===== */
.dsim-wrap { overflow-x: auto; margin: 0.4rem 0 0.8rem; }
.dsim { border-collapse: collapse; margin: 0 auto; font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 1.15rem; color: var(--forest); }
.dsim td { padding: 0.12rem 0.7rem; text-align: right; }
.dsim td.one { color: var(--ink-soft); }
.dsim td.pr { border-left: 3px solid var(--forest); text-align: left; min-width: 2.2rem; padding-left: 0.8rem; color: #d9650b; font-weight: 700; }
.dsim td.res { text-align: left; padding-left: 1.2rem; vertical-align: middle; font-size: 1rem; white-space: nowrap; }
.dsim td.res b { color: var(--forest); background: var(--lime); border-radius: 6px; padding: 0 0.4rem; }
.dsim-cap { display: none; text-align: center; font-family: 'IBM Plex Mono', ui-monospace, monospace; font-size: 0.95rem; color: var(--forest); margin-top: 0.4rem; }
.dsim-cap b { background: var(--lime); border-radius: 6px; padding: 0 0.4rem; }
@media (max-width: 560px) { .dsim td.res { display: none; } .dsim-cap { display: block; } .dsim { font-size: 1.05rem; } }

/* "mcm" siempre en minúsculas, aunque el recuadro ponga todo en mayúsculas */
.mcm { text-transform: none; }

/* MCD: los primos que dividen a todos a la vez van en azul; los demás, atenuados */
.dsim td.pr.com .pill { background: #2b6cb0; color: #fff; border-radius: 8px; padding: 0.05rem 0.55rem; }
.dsim td.pr.no { color: #b3ae9c; font-weight: 500; }
.dsim-leg { text-align: center; font-size: 0.88rem; color: var(--ink-soft); margin-top: 0.5rem; font-family: 'Karla', system-ui, sans-serif; }
.pill-leg { background: #2b6cb0; color: #fff; border-radius: 8px; padding: 0 0.5rem; font-weight: 700; }

/* pasos con frases completas (en vez de mayúsculas y letra espaciada) */
.regla-steps.claro .txt { text-transform: none; letter-spacing: 0; font-weight: 400; font-size: 1.02rem; line-height: 1.45; color: var(--ink); }

/* palabras grandes de los pasos: que siempre quepan dentro de su tarjeta */
.regla-step { min-width: 0; }
.regla-step .big { font-size: clamp(1.2rem, 5vw, 1.6rem); overflow-wrap: anywhere; max-width: 100%; }