/* ===========================================================
   AI Learning Hub — estilos
   =========================================================== */

:root {
  --bg: #0b0d12;
  --bg-soft: #11141c;
  --bg-card: #141824;
  --bg-card-hover: #1a1f2e;
  --border: #232838;
  --border-soft: #1b2030;
  --text: #e6e9f0;
  --text-dim: #9aa3b8;
  --text-faint: #6b7488;
  --accent: #7c9cff;
  --accent-2: #64e0c0;
  --accent-3: #ff9d6b;
  --accent-4: #d78bff;
  --shadow: 0 1px 3px rgba(0, 0, 0, .4), 0 8px 24px rgba(0, 0, 0, .25);
  --radius: 12px;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, Helvetica, Arial, sans-serif;
  --sidebar-w: 268px;
}

:root[data-theme="light"] {
  --bg: #f7f8fb;
  --bg-soft: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f1f3f9;
  --border: #dfe3ec;
  --border-soft: #e9ecf3;
  --text: #131722;
  --text-dim: #545c70;
  --text-faint: #808899;
  --accent: #3a63d8;
  --accent-2: #0f9b7c;
  --accent-3: #c4622a;
  --accent-4: #8b3fc4;
  --shadow: 0 1px 2px rgba(16, 24, 40, .06), 0 8px 24px rgba(16, 24, 40, .06);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 84px; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

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

code {
  font-family: var(--mono);
  font-size: .88em;
  background: var(--bg-soft);
  border: 1px solid var(--border-soft);
  border-radius: 5px;
  padding: 1px 5px;
}

/* ---------- Layout ---------- */

.layout {
  display: grid;
  grid-template-columns: var(--sidebar-w) minmax(0, 1fr);
  min-height: 100vh;
}

/* ---------- Sidebar ---------- */

.sidebar {
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
  border-right: 1px solid var(--border);
  background: var(--bg-soft);
  padding: 20px 14px 40px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 4px 8px 16px;
}

.brand-mark {
  width: 30px; height: 30px;
  border-radius: 9px;
  background: linear-gradient(135deg, var(--accent), var(--accent-4));
  display: grid; place-items: center;
  font-weight: 700; font-size: 15px; color: #fff;
  flex: none;
}

.brand-text { line-height: 1.2; }
.brand-text strong { display: block; font-size: 14.5px; letter-spacing: -.01em; }
.brand-text span { font-size: 11.5px; color: var(--text-faint); }

.nav-group-title {
  font-size: 10.5px;
  text-transform: uppercase;
  letter-spacing: .09em;
  color: var(--text-faint);
  padding: 16px 10px 6px;
  font-weight: 600;
}

.nav a {
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 6px 10px;
  border-radius: 8px;
  color: var(--text-dim);
  font-size: 13.5px;
  line-height: 1.35;
  text-decoration: none;
}
.nav a:hover { background: var(--bg-card-hover); color: var(--text); text-decoration: none; }
.nav a.active { background: var(--bg-card-hover); color: var(--text); font-weight: 600; }
.nav a .n-ico { width: 16px; text-align: center; flex: none; opacity: .85; }
.nav a .n-count { margin-left: auto; font-size: 10.5px; color: var(--text-faint); font-variant-numeric: tabular-nums; }

/* ---------- Main ---------- */

.main { min-width: 0; }

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  padding: 12px 32px;
  display: flex;
  gap: 12px;
  align-items: center;
}

.menu-btn {
  display: none;
  background: var(--bg-card); border: 1px solid var(--border);
  color: var(--text); border-radius: 9px; width: 36px; height: 36px;
  font-size: 16px; cursor: pointer; flex: none;
}

.search-wrap { position: relative; flex: 1; min-width: 0; max-width: 560px; }
.search-wrap::before {
  content: "⌕";
  position: absolute; left: 12px; top: 50%; transform: translateY(-52%);
  color: var(--text-faint); font-size: 17px; pointer-events: none;
}
#search {
  width: 100%;
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 10px;
  padding: 9px 12px 9px 32px;
  font-size: 14px;
  font-family: inherit;
  outline: none;
}
#search:focus { border-color: var(--accent); box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 18%, transparent); }
#search::placeholder { color: var(--text-faint); }

.kbd {
  position: absolute; right: 9px; top: 50%; transform: translateY(-50%);
  font-family: var(--mono); font-size: 10.5px; color: var(--text-faint);
  border: 1px solid var(--border); border-radius: 5px; padding: 1px 5px;
  pointer-events: none;
}

.topbar-actions { display: flex; gap: 8px; margin-left: auto; align-items: center; }

.btn {
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text-dim);
  border-radius: 9px;
  padding: 7px 12px;
  font-size: 13px;
  font-family: inherit;
  cursor: pointer;
  white-space: nowrap;
}
.btn:hover { background: var(--bg-card-hover); color: var(--text); }

.content { padding: 28px 32px 120px; max-width: 1080px; }

/* ---------- Hero ---------- */

.hero { padding: 26px 0 8px; }
.hero h1 {
  font-size: 38px; line-height: 1.12; margin: 0 0 12px;
  letter-spacing: -.028em; font-weight: 700;
}
.hero h1 em {
  font-style: normal;
  background: linear-gradient(100deg, var(--accent), var(--accent-4) 55%, var(--accent-2));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero p { color: var(--text-dim); font-size: 16px; max-width: 68ch; margin: 0 0 18px; }

.stats { display: flex; flex-wrap: wrap; gap: 10px; margin: 22px 0 8px; }
.stat {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: 10px; padding: 10px 14px; min-width: 96px;
}
.stat b { display: block; font-size: 20px; letter-spacing: -.02em; font-variant-numeric: tabular-nums; }
.stat span { font-size: 11.5px; color: var(--text-faint); }

/* ---------- Filtros ---------- */

.filters {
  display: flex; flex-wrap: wrap; gap: 6px;
  padding: 16px 0 6px;
  border-top: 1px solid var(--border-soft);
  margin-top: 26px;
}
.filter-label {
  font-size: 11px; color: var(--text-faint); text-transform: uppercase;
  letter-spacing: .07em; width: 100%; margin-bottom: 2px; font-weight: 600;
}
.chip {
  background: var(--bg-card); border: 1px solid var(--border);
  color: var(--text-dim); border-radius: 999px; padding: 4px 11px;
  font-size: 12.5px; cursor: pointer; font-family: inherit;
  display: inline-flex; align-items: center; gap: 5px;
}
.chip:hover { background: var(--bg-card-hover); color: var(--text); }
.chip[aria-pressed="true"] { background: var(--accent); border-color: var(--accent); color: #fff; font-weight: 600; }
:root[data-theme="light"] .chip[aria-pressed="true"] { color: #fff; }

.results-meta {
  font-size: 13px; color: var(--text-faint);
  padding: 14px 0 0; display: flex; align-items: center; gap: 10px;
}

/* ---------- Secciones ---------- */

.section { padding-top: 46px; scroll-margin-top: 80px; }
.section > h2 {
  font-size: 24px; letter-spacing: -.02em; margin: 0 0 6px;
  display: flex; align-items: center; gap: 10px;
}
.section > h2 .sec-ico { font-size: 22px; }
.section > .sec-desc {
  color: var(--text-dim); margin: 0 0 18px; max-width: 74ch; font-size: 14.5px;
}

.subhead {
  font-size: 12px; text-transform: uppercase; letter-spacing: .08em;
  color: var(--text-faint); font-weight: 600;
  margin: 26px 0 10px; padding-bottom: 6px;
  border-bottom: 1px solid var(--border-soft);
}

/* ---------- Cards ---------- */

.cards { display: grid; gap: 9px; }

.card {
  display: block;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 13px 15px;
  color: inherit;
  text-decoration: none;
  transition: border-color .13s, background .13s, transform .13s;
}
.card:hover {
  background: var(--bg-card-hover);
  border-color: color-mix(in srgb, var(--accent) 45%, var(--border));
  text-decoration: none;
  transform: translateY(-1px);
}

.card-top { display: flex; align-items: baseline; gap: 9px; flex-wrap: wrap; }
.card-title { font-weight: 600; font-size: 14.5px; letter-spacing: -.008em; }
.card:hover .card-title { color: var(--accent); }
.card-author { font-size: 12.5px; color: var(--text-faint); }
.card-note { color: var(--text-dim); font-size: 13.5px; margin: 5px 0 0; }

.card-meta { display: flex; flex-wrap: wrap; gap: 5px; margin-top: 9px; align-items: center; }

.tag {
  font-size: 10.5px; letter-spacing: .02em;
  border-radius: 5px; padding: 1.5px 6px;
  border: 1px solid var(--border);
  color: var(--text-faint);
  background: var(--bg-soft);
  white-space: nowrap;
}
.tag.type { color: var(--accent); border-color: color-mix(in srgb, var(--accent) 35%, transparent); background: color-mix(in srgb, var(--accent) 10%, transparent); font-weight: 600; }
.tag.lvl-intro { color: var(--accent-2); border-color: color-mix(in srgb, var(--accent-2) 35%, transparent); background: color-mix(in srgb, var(--accent-2) 10%, transparent); }
.tag.lvl-medio { color: var(--accent-3); border-color: color-mix(in srgb, var(--accent-3) 35%, transparent); background: color-mix(in srgb, var(--accent-3) 10%, transparent); }
.tag.lvl-avanzado { color: var(--accent-4); border-color: color-mix(in srgb, var(--accent-4) 35%, transparent); background: color-mix(in srgb, var(--accent-4) 10%, transparent); }
.tag.es { color: var(--text-dim); }
.tag.free { color: var(--accent-2); border-color: color-mix(in srgb, var(--accent-2) 30%, transparent); }
.tag.year { font-variant-numeric: tabular-nums; }

.star { color: var(--accent-3); font-size: 12px; margin-left: 2px; }

/* ---------- Prosa (futuro, roadmaps) ---------- */

.prose { max-width: 76ch; }
.prose h3 { font-size: 17px; margin: 30px 0 8px; letter-spacing: -.012em; }
.prose h4 { font-size: 14.5px; margin: 22px 0 6px; color: var(--text); }
.prose p { color: var(--text-dim); margin: 0 0 12px; }
.prose ul, .prose ol { color: var(--text-dim); padding-left: 20px; margin: 0 0 14px; }
.prose li { margin-bottom: 6px; }
.prose strong { color: var(--text); font-weight: 600; }

.callout {
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  background: var(--bg-card);
  border-radius: 10px;
  padding: 13px 16px;
  margin: 18px 0;
}
.callout.warn { border-left-color: var(--accent-3); }
.callout.good { border-left-color: var(--accent-2); }
.callout p:last-child { margin-bottom: 0; }
.callout-title { font-weight: 600; color: var(--text); font-size: 13.5px; margin-bottom: 4px; }

/* Roadmap */
.roadmap { display: grid; gap: 12px; grid-template-columns: repeat(auto-fit, minmax(272px, 1fr)); }
.rm-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 16px 17px;
}
.rm-card h4 { margin: 0 0 3px; font-size: 15px; display: flex; align-items: center; gap: 8px; }
.rm-card .rm-for { font-size: 12px; color: var(--text-faint); margin-bottom: 11px; }
.rm-card ol { margin: 0; padding-left: 18px; font-size: 13.5px; color: var(--text-dim); }
.rm-card ol li { margin-bottom: 6px; }
.rm-card ol li strong { color: var(--text); }

/* Tabla */
.table-wrap { overflow-x: auto; margin: 16px 0; border: 1px solid var(--border); border-radius: var(--radius); }
table { border-collapse: collapse; width: 100%; font-size: 13.5px; min-width: 560px; }
th, td { text-align: left; padding: 9px 14px; border-bottom: 1px solid var(--border-soft); vertical-align: top; }
th { background: var(--bg-soft); font-size: 11.5px; text-transform: uppercase; letter-spacing: .06em; color: var(--text-faint); font-weight: 600; }
tbody tr:last-child td { border-bottom: none; }
td { color: var(--text-dim); }
td:first-child { color: var(--text); font-weight: 500; }

/* Timeline */
.timeline { position: relative; padding-left: 26px; margin: 18px 0; }
.timeline::before {
  content: ""; position: absolute; left: 6px; top: 6px; bottom: 6px;
  width: 2px; background: var(--border);
}
.tl-item { position: relative; margin-bottom: 20px; }
.tl-item::before {
  content: ""; position: absolute; left: -23px; top: 8px;
  width: 9px; height: 9px; border-radius: 50%;
  background: var(--accent); border: 2px solid var(--bg);
}
.tl-year { font-family: var(--mono); font-size: 12px; color: var(--accent); font-weight: 600; }
.tl-item h4 { margin: 1px 0 3px; font-size: 14.5px; }
.tl-item p { margin: 0; font-size: 13.5px; color: var(--text-dim); }

.empty { color: var(--text-faint); padding: 40px 0; text-align: center; font-size: 14px; }

/* Modo búsqueda: las secciones se ocultan y queda la lista de resultados */
#results-section { display: none; padding-top: 20px; }
body.filtering #results-section { display: block; }
body.filtering .section { display: none; }
body.filtering .hero { display: none; }

footer {
  border-top: 1px solid var(--border);
  margin-top: 70px; padding-top: 22px;
  color: var(--text-faint); font-size: 13px;
}

/* ---------- Responsive ---------- */

@media (max-width: 900px) {
  .layout { grid-template-columns: 1fr; }
  .sidebar {
    position: fixed; z-index: 60; left: 0; top: 0; width: 280px;
    transform: translateX(-100%); transition: transform .2s ease;
    box-shadow: var(--shadow);
  }
  .sidebar.open { transform: none; }
  .menu-btn { display: block; }
  .content { padding: 20px 18px 100px; }
  .topbar { padding: 10px 18px; }
  .hero h1 { font-size: 29px; }
  .scrim { position: fixed; inset: 0; background: rgba(0,0,0,.5); z-index: 50; }
}

@media print {
  .sidebar, .topbar, .filters { display: none; }
  .layout { display: block; }
  body { background: #fff; color: #000; }
}

/* ===========================================================
   Sitio multipágina: migas, encabezados de página, FAQ y navegación
   entre temas. Todo lo de abajo se agregó junto con el generador estático.
   =========================================================== */

/* ---------- Accesibilidad ---------- */

.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}
.skip-link {
  position: absolute; left: -9999px; top: 0; z-index: 100;
  background: var(--accent); color: #fff; padding: 10px 16px;
  border-radius: 0 0 8px 0; font-size: 14px; font-weight: 600;
}
.skip-link:focus { left: 0; text-decoration: none; }

:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 4px; }

/* ---------- Marca (ahora es un enlace a la portada) ---------- */

a.brand { color: inherit; }
a.brand:hover { text-decoration: none; }
a.brand:hover .brand-text strong { color: var(--accent); }

.nav a[aria-current="page"] {
  background: var(--bg-card-hover); color: var(--text); font-weight: 600;
}

/* ---------- Migas de pan ---------- */

.breadcrumb { padding-top: 18px; font-size: 12.5px; color: var(--text-faint); }
.breadcrumb ol { list-style: none; display: flex; flex-wrap: wrap; gap: 6px; margin: 0; padding: 0; }
.breadcrumb li + li::before { content: "/"; margin-right: 6px; color: var(--border); }
.breadcrumb a { color: var(--text-faint); }
.breadcrumb a:hover { color: var(--accent); }

/* ---------- Encabezado de página interna ---------- */

.page-hero { padding-top: 14px; }
.page-hero h1 { font-size: 32px; }
.hero .lede, p.lede { font-size: 16.5px; color: var(--text-dim); max-width: 70ch; }
.hero .lede p { font-size: 16.5px; }
.hero .lede p:last-child { margin-bottom: 0; }

.byline-top { font-size: 12.5px; color: var(--text-faint); margin-top: 16px; }
.ruta-para { color: var(--text-faint); font-size: 13.5px; margin: 0 0 14px; }
.ruta-meta {
  font-size: 13px; color: var(--text-dim); margin-top: 18px;
  border-left: 3px solid var(--accent); padding-left: 12px;
}

/* ---------- Portada: grupos y vistas previas ---------- */

.group-heading {
  font-size: 13px; text-transform: uppercase; letter-spacing: .09em;
  color: var(--text-faint); font-weight: 700;
  margin: 56px 0 0; padding-top: 22px; border-top: 1px solid var(--border-soft);
}
#temas.group-heading { margin-bottom: 6px; }

.section > h3 {
  font-size: 20px; letter-spacing: -.02em; margin: 0 0 6px;
  display: flex; align-items: center; gap: 10px;
}
.section > h3 a { color: var(--text); }
.section > h3 a:hover { color: var(--accent); }
.section > h3 .sec-ico { font-size: 19px; }

p.more { margin: 14px 0 0; font-size: 13.5px; }
p.more a, .rm-more a { font-weight: 600; }

/* ---------- Rutas ---------- */

.rm-card h3 { margin: 0 0 3px; font-size: 15.5px; display: flex; align-items: center; gap: 8px; }
.rm-card h3 a { color: var(--text); }
.rm-card h3 a:hover { color: var(--accent); }
.rm-more { margin: 12px 0 0; font-size: 12.5px; }

.pasos { list-style: none; counter-reset: paso; padding: 0; margin: 0; }
.pasos > li {
  counter-increment: paso;
  position: relative; padding: 0 0 22px 46px; margin: 0;
  border-left: 2px solid var(--border-soft); margin-left: 15px;
}
.pasos > li:last-child { border-left-color: transparent; padding-bottom: 0; }
.pasos > li::before {
  content: counter(paso);
  position: absolute; left: -16px; top: 0;
  width: 30px; height: 30px; border-radius: 50%;
  background: var(--bg-card); border: 1px solid var(--border);
  color: var(--accent); font-weight: 700; font-size: 13px;
  display: flex; align-items: center; justify-content: center;
  font-variant-numeric: tabular-nums;
}
.pasos h3 { margin: 4px 0 6px; font-size: 16px; letter-spacing: -.01em; }
.pasos p { color: var(--text-dim); margin: 0 0 8px; max-width: 70ch; font-size: 14.5px; }
.paso-link { font-size: 13px; }

/* ---------- Preguntas frecuentes ---------- */

.faq details {
  border: 1px solid var(--border); border-radius: 10px;
  background: var(--bg-card); margin-bottom: 8px; overflow: hidden;
}
.faq summary {
  cursor: pointer; padding: 13px 16px; list-style: none;
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+"; color: var(--text-faint); font-size: 18px; line-height: 1; flex: none;
}
.faq details[open] summary::after { content: "−"; }
.faq summary:hover { background: var(--bg-card-hover); }
.faq summary h3 { margin: 0; font-size: 15px; font-weight: 600; letter-spacing: -.01em; }
.faq .faq-a { padding: 0 16px 14px; }
.faq .faq-a p { margin: 0; color: var(--text-dim); max-width: 74ch; font-size: 14.5px; }

/* ---------- Temas relacionados ---------- */

.related { margin-top: 56px; padding-top: 26px; border-top: 1px solid var(--border-soft); }
.related h2 { font-size: 18px; margin: 0 0 14px; letter-spacing: -.02em; }
.related ul {
  list-style: none; padding: 0; margin: 0;
  display: grid; gap: 10px; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}
.related li a {
  display: block; background: var(--bg-card); border: 1px solid var(--border);
  border-radius: 10px; padding: 13px 15px; color: var(--text);
  font-weight: 600; font-size: 14.5px;
}
.related li a:hover { background: var(--bg-card-hover); border-color: var(--accent); text-decoration: none; }
.related li a em {
  display: block; font-style: normal; font-weight: 400;
  color: var(--text-faint); font-size: 12.5px; margin-top: 4px; line-height: 1.5;
}

/* ---------- Prosa ---------- */

.prose h2 {
  font-size: 21px; margin: 38px 0 10px; letter-spacing: -.02em;
  padding-top: 4px;
}
.prose h2:first-child { margin-top: 0; }
.prose a { text-decoration: underline; text-underline-offset: 2px; }
.home-intro { margin-top: 34px; }
.guia h2 { border-top: 1px solid var(--border-soft); padding-top: 28px; }
.guia h2:first-child { border-top: 0; padding-top: 0; }

/* ---------- Línea de tiempo (ahora con h2) ---------- */

.tl-item h2 { margin: 1px 0 3px; font-size: 15px; letter-spacing: -.01em; }

/* ---------- Modo búsqueda ---------- */

body.filtering #page-content { display: none; }
.subhead a { color: inherit; }
.subhead a:hover { color: var(--accent); }

/* ---------- Pie ---------- */

footer .byline { color: var(--text-dim); }
footer .byline span { color: var(--text-faint); }
footer .foot-nav { margin-top: 14px; }

@media (max-width: 900px) {
  .page-hero h1 { font-size: 26px; }
  .pasos > li { padding-left: 34px; }
}

/* ---------- Colecciones ---------- */

.related.colecciones { margin-top: 18px; padding-top: 0; border-top: 0; }
.related.colecciones ul { grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }

/* ---------- Índice de temas ---------- */

.tema-index { list-style: none; padding: 0; margin: 0; }
.tema-index li {
  display: grid; grid-template-columns: 1fr auto; gap: 2px 14px;
  padding: 12px 0; border-bottom: 1px solid var(--border-soft);
}
.tema-index li a { font-weight: 600; font-size: 15.5px; color: var(--text); }
.tema-index li a:hover { color: var(--accent); text-decoration: none; }
.tema-count {
  font-size: 12px; color: var(--text-faint); white-space: nowrap;
  font-variant-numeric: tabular-nums;
}
.tema-index li em {
  grid-column: 1 / -1; font-style: normal;
  color: var(--text-dim); font-size: 13.5px; max-width: 78ch;
}
.group-heading a { color: inherit; }
.group-heading a:hover { color: var(--accent); }