:root {
  --papel: #FCFAF5;
  --papel-profundo: #F7F3EA;
  --superficie: #FFFFFF;
  --superficie-suave: #F3EFE5;
  --renglon: #E3DCCD;
  --tinta: #221F19;
  --tinta-suave: #6B675C;
  --margen: #3F6756;
  --resaltador: #CFE0D7;
  --dominio: #3F6756;
  --ascua: #C05A2E;
  --blanco: #FFFFFF;
  --linea-h: 30px;
  --borde-margen: clamp(28px, 7vw, 96px);
  --radio: 8px;
  --sombra-suave: 0 12px 30px rgba(23, 32, 27, .07), 0 2px 6px rgba(23, 32, 27, .05);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

[hidden] {
  display: none !important;
}

body {
  min-height: 100dvh;
  color: var(--tinta);
  background: var(--papel);
  font-family: "IBM Plex Sans", system-ui, sans-serif;
  line-height: var(--linea-h);
}

body::before {
  display: none;
}

a {
  color: var(--tinta);
}

button,
input,
textarea {
  font: inherit;
}

.materia,
.rotulo,
.meta,
.quien,
.insignia,
code,
kbd {
  font-family: "IBM Plex Mono", ui-monospace, monospace;
}

.pagina {
  position: relative;
  z-index: 1;
  width: min(1240px, 100%);
  margin-inline: auto;
  padding: 0 clamp(22px, 5vw, 74px) calc(var(--linea-h) * 3);
}

.pagina-estrecha {
  width: min(760px, 100%);
  margin-inline: auto;
  padding-left: clamp(20px, 4vw, 64px);
}

.barra {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 20px;
  min-height: calc(var(--linea-h) * 3);
  padding-top: calc(env(safe-area-inset-top, 0px) + (var(--linea-h) * .55));
  line-height: calc(var(--linea-h) * 1.4);
}

.marca {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  color: var(--tinta);
  font-family: "IBM Plex Sans", system-ui, sans-serif;
  font-size: 25px;
  font-weight: 800;
  letter-spacing: -.02em;
  text-decoration: none;
}

.marca-flame {
  display: block;
  width: auto;
  height: 31px;
  flex: 0 0 auto;
  object-fit: contain;
}

.nav-enlaces {
  display: flex;
  flex-wrap: nowrap;
  align-items: center;
  gap: clamp(16px, 3vw, 42px);
  white-space: nowrap;
}

.nav-enlaces.nav-enlaces--creator {
  gap: clamp(10px, 2.1vw, 34px);
}

.nav-enlaces a {
  border-bottom: 1px solid transparent;
  border-radius: 999px;
  color: var(--tinta);
  font-family: "IBM Plex Sans", system-ui, sans-serif;
  font-size: 16px;
  font-weight: 500;
  letter-spacing: 0;
  line-height: 1.35;
  padding: 5px 11px;
  text-decoration: none;
}

.nav-enlaces a:hover,
.nav-enlaces a:focus-visible {
  border-bottom-color: var(--margen);
}

.nav-enlaces a[aria-current="page"] {
  border-color: var(--margen);
  background: var(--margen);
  color: var(--blanco);
  font-weight: 600;
}

.nav-enlaces .enlace-nav {
  all: unset;
  border-bottom: 1px solid transparent;
  border-radius: 999px;
  color: var(--tinta-suave);
  cursor: pointer;
  font-family: "IBM Plex Sans", system-ui, sans-serif;
  font-size: 16px;
  font-weight: 500;
  line-height: 1.35;
  padding: 5px 11px;
}

.nav-enlaces .enlace-nav:hover,
.nav-enlaces .enlace-nav:focus-visible {
  border-bottom-color: var(--margen);
  outline: none;
}

@media (max-width: 980px) and (min-width: 701px) {
  .nav-enlaces.nav-enlaces--creator {
    gap: clamp(6px, 1.1vw, 12px);
  }

  .nav-enlaces.nav-enlaces--creator a,
  .nav-enlaces.nav-enlaces--creator .enlace-nav {
    padding-right: 8px;
    padding-left: 8px;
  }
}

.materia {
  color: var(--dominio);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  font-family: "IBM Plex Sans", system-ui, sans-serif;
  letter-spacing: -.02em;
}

h1 {
  max-width: 16ch;
  padding: calc(var(--linea-h) / 2) 0 calc(var(--linea-h) / 3);
  font-size: clamp(38px, 5.4vw, 58px);
  font-weight: 800;
  line-height: 1.04;
}

h2 {
  font-size: clamp(23px, 3vw, 30px);
  line-height: calc(var(--linea-h) * 1.15);
}

.resaltado {
  padding: 0;
  background: none;
}

.intro,
.texto-suave {
  max-width: 56ch;
  color: var(--tinta-suave);
}

.paneles-auth {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(20px, 4vw, 42px);
  padding-top: var(--linea-h);
}

.hoja {
  position: relative;
  padding: calc(var(--linea-h) * .8) clamp(18px, 3vw, 28px) var(--linea-h);
  border: 1px solid rgba(63, 103, 86, .14);
  border-radius: var(--radio);
  background: var(--blanco);
  box-shadow: 0 1px 3px rgba(34, 31, 25, .04);
}

.hoja::before {
  content: "";
  position: absolute;
  top: -10px;
  left: 34px;
  width: 78px;
  height: 22px;
  border: 1px solid rgba(192, 90, 46, .14);
  background: color-mix(in srgb, #F0D9B8 70%, transparent);
  transform: rotate(-4deg);
}

.formulario {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding-top: calc(var(--linea-h) / 2);
}

.campo {
  display: flex;
  flex-direction: column;
  gap: 5px;
}

label {
  font-size: 14px;
  font-weight: 700;
  line-height: 1.3;
}

input[type="email"],
input[type="password"],
input[type="text"],
textarea,
select {
  width: 100%;
  padding: 10px 14px;
  border: 1px solid rgba(63, 103, 86, .3);
  border-radius: var(--radio);
  background: var(--blanco);
  color: var(--tinta);
  line-height: 1.45;
}

input:focus-visible,
textarea:focus-visible,
select:focus-visible,
button:focus-visible,
.boton:focus-visible {
  outline: 3px solid var(--resaltador);
  outline-offset: 1px;
}

.boton,
button {
  display: inline-flex;
  min-height: 36px;
  align-items: center;
  justify-content: center;
  align-self: flex-start;
  padding: 6px 16px;
  border: 1px solid var(--margen);
  border-radius: 999px;
  background: var(--margen);
  box-shadow: none;
  color: var(--blanco);
  cursor: pointer;
  font-family: "IBM Plex Sans", system-ui, sans-serif;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: .01em;
  line-height: 1.4;
  text-decoration: none;
  transition: background-color .15s ease, border-color .15s ease;
}

.boton:hover,
button:hover {
  background: color-mix(in srgb, var(--margen) 86%, var(--ascua));
  border-color: color-mix(in srgb, var(--margen) 86%, var(--ascua));
  box-shadow: none;
  transform: none;
}

.boton.secundario,
button.secundario {
  border-color: rgba(63, 103, 86, .35);
  background: transparent;
  box-shadow: none;
  color: var(--margen);
}

.boton.secundario:hover,
button.secundario:hover {
  background: color-mix(in srgb, var(--margen) 8%, transparent);
  border-color: rgba(63, 103, 86, .55);
  box-shadow: none;
}

button:disabled {
  cursor: default;
  opacity: .55;
}

.acciones {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  padding-top: calc(var(--linea-h) / 2);
}

.estado {
  min-height: var(--linea-h);
  color: var(--tinta-suave);
  font-style: italic;
}

.estado.error {
  color: var(--margen);
  font-style: normal;
  font-weight: 700;
}

.estado.ok {
  color: var(--dominio);
  font-style: normal;
  font-weight: 700;
}

.insignias {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
  padding-top: calc(var(--linea-h) / 3);
}

.insignia {
  display: inline-flex;
  align-items: center;
  min-height: 26px;
  padding: 2px 9px;
  border: 1px solid rgba(30, 42, 74, .28);
  border-radius: 999px;
  background: var(--blanco);
  color: var(--tinta-suave);
  font-size: 12px;
  font-weight: 700;
  line-height: 1.2;
}

.insignia.destacada {
  border-color: rgba(214, 69, 69, .36);
  background: color-mix(in srgb, var(--resaltador) 36%, var(--blanco));
  color: var(--tinta);
}

.separador {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--tinta-suave);
  font-size: 13px;
  line-height: var(--linea-h);
}

.separador::before,
.separador::after {
  content: "";
  height: 1px;
  flex: 1;
  background: var(--renglon);
}

.nota-pie {
  padding-top: var(--linea-h);
  color: var(--tinta-suave);
  font-size: 14px;
}

/* ---------------- pestañas de índice (como separadores de lumbre) */
.pestanas {
  display: flex;
  gap: 8px;
  padding: 0 0 0 22px;
}

.pestana {
  align-self: flex-end;
  padding: 6px 20px 8px;
  border: 1px solid rgba(30, 42, 74, .3);
  border-bottom: none;
  border-radius: 10px 10px 0 0;
  background: color-mix(in srgb, var(--blanco) 55%, var(--papel));
  box-shadow: none;
  color: var(--tinta-suave);
  font-size: 15px;
  font-weight: 600;
}

.pestana[aria-selected="true"] {
  position: relative;
  z-index: 2;
  margin-bottom: -1px;
  padding-bottom: 9px;
  background: var(--blanco);
  color: var(--tinta);
  font-weight: 700;
}

.hoja.sin-cinta::before {
  display: none;
}

/* ---------------- tarjetas de lumbre (portada + etiqueta), compartidas */
.catalogo {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 380px), 1fr));
  gap: clamp(20px, 2.5vw, 30px);
  padding: calc(var(--linea-h) * .8) 0 var(--linea-h);
}

.lumbre {
  display: grid;
  grid-template-columns: 124px minmax(0, 1fr);
  align-items: start;
  overflow: hidden;
  min-height: 192px;
  border: 1px solid rgba(63, 103, 86, .12);
  border-radius: var(--radio);
  background: var(--superficie);
  box-shadow: 0 1px 3px rgba(34, 31, 25, .04);
  transition: border-color .15s ease, box-shadow .15s ease;
}

.lumbre:hover,
.lumbre:focus-within {
  transform: none;
  border-color: rgba(63, 103, 86, .3);
  box-shadow: var(--sombra-suave);
}

.pasta {
  position: relative;
  display: block;
  width: 88px;
  height: 88px;
  min-height: 0;
  margin: 26px 0 0 26px;
  border: 1px solid rgba(63, 103, 86, .08);
  border-radius: 7px;
  background: radial-gradient(120% 120% at 30% 20%, #F6E9D4 0%, #EFDFC4 48%, #E7D2AE 100%);
  background-position: center;
  background-size: cover;
}

.etiqueta {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 24px 26px 0;
}

.etiqueta .rotulo {
  color: var(--dominio);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .02em;
  line-height: 1.2;
}

.etiqueta .titulo {
  padding-bottom: 12px;
  border-bottom: 1px solid rgba(63, 103, 86, .18);
  font-family: "IBM Plex Sans", system-ui, sans-serif;
  font-size: clamp(20px, 2.2vw, 24px);
  font-weight: 700;
  line-height: 1.16;
}

.etiqueta .alumno {
  color: var(--tinta);
  font-size: 15px;
  line-height: 1.35;
}

.contenido-lumbre {
  display: flex;
  min-width: 0;
  flex-direction: column;
}

.paginas {
  display: flex;
  flex: 1;
  flex-direction: column;
  gap: 11px;
  padding: 12px 26px 22px;
}

.paginas p {
  flex: 1;
  font-size: 14px;
  line-height: 1.45;
}

.paginas .meta {
  flex: none;
  color: var(--tinta-suave);
  font-size: 12px;
  line-height: 1.4;
}

.paginas .boton {
  align-self: flex-end;
  margin-top: 2px;
  padding: 9px 18px;
  font-size: 15px;
}

.clamp-3 {
  display: -webkit-box;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 3;
  line-clamp: 3;
  overflow: hidden;
}

@media (prefers-reduced-motion: reduce) {
  .lumbre,
  .lumbre:hover,
  .lumbre:focus-within {
    transform: none;
    transition: none;
  }
}

/* ---------------- notas adhesivas (perfil) */
.nota-adhesiva {
  position: relative;
  padding: calc(var(--linea-h) * .6) 18px var(--linea-h);
  border: 1px solid rgba(63, 103, 86, .14);
  border-radius: 2px;
  box-shadow: none;
}

.nota-adhesiva h2 {
  font-size: 17px;
}

.nota-amarilla { background: #F7EDD8; }
.nota-rosada { background: #F4E4DA; }
.nota-azul { background: #E9EFE4; }

@media (max-width: 860px) {
  .paneles-auth {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 700px) {
  :root {
    --borde-margen: 18px;
  }

  .pagina {
    padding-right: 16px;
    padding-left: 16px;
  }

  .barra {
    align-items: flex-start;
    flex-direction: column;
    gap: 0;
    padding-top: calc(env(safe-area-inset-top, 0px) + (var(--linea-h) / 2));
    line-height: var(--linea-h);
  }

  .nav-enlaces {
    flex-wrap: wrap;
    gap: 4px 18px;
    white-space: normal;
  }

  .lumbre {
    grid-template-columns: 1fr;
  }

  .pasta {
    margin: 22px auto 0;
  }

  .pasta::before {
    top: 50%;
  }

  .etiqueta,
  .paginas {
    padding-right: 20px;
    padding-left: 20px;
  }

  .etiqueta {
    padding-top: 22px;
  }
}

/* ---- chat del tutor: markdown y widgets (aprender.html y probar.html) ---- */
.msg.tutor { white-space: normal; }
.msg.tutor .md-plano { white-space: pre-wrap; }
.msg.tutor .md > * { margin: 0; padding: 0 0 calc(var(--linea-h) / 3); }
.msg.tutor .md > *:last-child { padding-bottom: 0; }
.msg.tutor .md strong { color: var(--tinta); font-weight: 700; }
.msg.tutor .md ul,
.msg.tutor .md ol { padding-left: 1.4em; }
.msg.tutor .md li { padding-bottom: 4px; }
.msg.tutor .md blockquote {
  margin: 4px 0;
  padding: 8px 14px;
  border-left: 3px solid var(--dominio);
  border-radius: 0 var(--radio) var(--radio) 0;
  background: color-mix(in srgb, var(--resaltador) 30%, var(--blanco));
  color: var(--tinta);
}
.msg.tutor .md table {
  margin: 4px 0;
  border-collapse: collapse;
  font-size: 14px;
  line-height: 1.45;
}
.msg.tutor .md th,
.msg.tutor .md td {
  padding: 5px 12px;
  border: 1px solid var(--renglon);
  text-align: left;
}
.msg.tutor .md th {
  background: var(--superficie-suave);
  color: var(--tinta-suave);
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .06em;
  text-transform: uppercase;
}
.msg.tutor .md code {
  padding: 1px 5px;
  border-radius: 4px;
  background: var(--superficie-suave);
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: .9em;
}
.msg.tutor pre {
  overflow-x: auto;
  margin: 4px 0;
  padding: 10px 14px;
  border: 1px solid var(--renglon);
  border-radius: var(--radio);
  background: var(--superficie-suave);
  font-size: 13px;
  line-height: 1.5;
  white-space: pre;
}

/* opciones tocables (quiz y práctica) */
.opciones-chat {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 8px 0 2px;
}
.opciones-chat button {
  display: flex;
  gap: 8px;
  align-items: baseline;
  min-height: 40px;
  padding: 8px 16px;
  border: 1px solid rgba(192, 90, 46, .35);
  border-radius: 12px;
  background: var(--superficie);
  color: var(--tinta);
  cursor: pointer;
  font-size: 15px;
  line-height: 1.45;
  text-align: left;
  transition: border-color .12s ease, background .12s ease, transform .12s ease;
}
.opciones-chat button:hover:not(:disabled) {
  border-color: var(--ascua);
  background: color-mix(in srgb, var(--ascua) 6%, var(--superficie));
  transform: translateX(2px);
}
.opciones-chat button:disabled { cursor: default; opacity: .65; }
.opciones-chat button.elegida {
  border-color: var(--dominio);
  background: color-mix(in srgb, var(--resaltador) 35%, var(--blanco));
  opacity: 1;
}
.opciones-chat .opcion-letra {
  flex: none;
  color: var(--ascua);
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 13px;
  font-weight: 700;
}
.opciones-chat.historica button { opacity: .75; }

/* pista tocable */
.msg.tutor details.pista {
  margin: 6px 0 2px;
  padding: 8px 14px;
  border: 1.5px dashed color-mix(in srgb, var(--ascua) 50%, transparent);
  border-radius: var(--radio);
  background: color-mix(in srgb, var(--ascua) 4%, var(--superficie));
}
.msg.tutor details.pista summary {
  color: var(--ascua);
  cursor: pointer;
  font-size: 14px;
  font-weight: 700;
}
.msg.tutor details.pista p { padding: 6px 0 0; font-size: 15px; }

/* divisor de capítulo: la línea 📍 del tutor convertida en sensación de avance */
.divisor-capitulo {
  display: flex;
  flex-direction: column;
  gap: 2px;
  margin: calc(var(--linea-h) / 3) 0;
  padding: 10px 16px;
  border-top: 1px dashed var(--renglon);
  border-left: 3px solid var(--dominio);
  border-radius: 0 var(--radio) var(--radio) 0;
  background: color-mix(in srgb, var(--resaltador) 18%, var(--papel));
  animation: divisorEntra .45s ease;
}
.divisor-capitulo .divisor-modulo {
  color: var(--tinta-suave);
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
}
.divisor-capitulo .divisor-concepto {
  color: var(--dominio);
  font-size: 16px;
  font-weight: 700;
}
@keyframes divisorEntra {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

.widget-cargando {
  display: inline-block;
  color: var(--tinta-suave);
  animation: parpadeoWidget 1.2s ease-in-out infinite;
}
@keyframes parpadeoWidget { 50% { opacity: .3; } }

@media (prefers-reduced-motion: reduce) {
  .divisor-capitulo, .widget-cargando { animation: none; }
  .opciones-chat button { transition: none; }
}

.divisor-capitulo .divisor-arte {
  width: min(220px, 100%);
  margin-bottom: 6px;
  border-radius: var(--radio);
}