/* =============================================================
   1. Tokens
   ============================================================= */
:root {
  --bg: #0b0f14;
  --surface: #121821;
  --surface-2: #1a222e;
  --surface-3: #222c3a;
  --line: #263243;
  --text: #e6edf3;
  --muted: #8c99ab;
  --accent: #f2b84b;          /* ámbar de cabina: cálido y suave de noche */
  --accent-ink: #1a1304;
  --key-num: #7cc0ff;
  --key-func: #ff8f85;
  --key-eq: #ff6b5e;
  --bad: #ff8f85;
  --good: #7ee2a8;

  --sans: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;

  --radius: 14px;
  --gutter: 16px;
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
}

/* =============================================================
   2. Reset & base
   ============================================================= */
*, *::before, *::after { box-sizing: border-box; margin: 0; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; color-scheme: dark; }
body {
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: clip;
}
img, svg { display: block; max-width: 100%; }
button { font: inherit; color: inherit; cursor: pointer; border: 0; background: none; }
a { color: inherit; }
p { text-wrap: pretty; }
h1, h2, h3 { text-wrap: balance; line-height: 1.2; letter-spacing: -0.015em; }
::selection { background: var(--accent); color: var(--accent-ink); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 6px; }

/* =============================================================
   3. Utilities
   ============================================================= */
.container { width: 100%; max-width: 860px; margin-inline: auto; padding-inline: var(--gutter); }
.muted { color: var(--muted); }
.skip-link {
  position: fixed; top: -100px; left: 1rem; z-index: 99;
  padding: .6rem 1rem; border-radius: 8px; font-weight: 600;
  background: var(--accent); color: var(--accent-ink); text-decoration: none;
}
.skip-link:focus { top: 1rem; }
.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; }

/* =============================================================
   4. Typography
   ============================================================= */
h1 { font-size: clamp(1.3rem, 1rem + 1.6vw, 1.9rem); font-weight: 700; }
h2 { font-size: clamp(1.25rem, 1.05rem + 1vw, 1.6rem); font-weight: 700; margin-bottom: .75rem; }
h3 { font-size: 1.05rem; font-weight: 600; }
kbd, .seq {
  font-family: var(--mono); font-size: .86em; font-weight: 500;
  padding: .1em .42em; border-radius: 6px; white-space: nowrap;
  background: var(--surface-2); border: 1px solid var(--line); color: var(--text);
}
.seq { color: var(--accent); }

/* =============================================================
   5. Components
   ============================================================= */
/* Header */
.site-header { border-bottom: 1px solid var(--line); background: rgba(11, 15, 20, .85); }
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 48px; }
.logo { display: inline-flex; align-items: center; gap: .5rem; font-weight: 700; text-decoration: none; letter-spacing: -0.01em; }
.logo svg { color: var(--accent); }
.header-nav { display: flex; gap: 1.1rem; font-size: .9rem; }
.header-nav a { color: var(--muted); text-decoration: none; padding: .4rem 0; transition: color .2s var(--ease-out); }
.header-nav a:hover { color: var(--text); }
/* Selector de idioma: los dos idiomas a la vista, con el actual marcado */
.header-nav { align-items: center; }
.lang-toggle {
  display: inline-flex; align-items: center; gap: 2px; padding: 2px 2px 2px 8px;
  border: 1px solid var(--line); border-radius: 999px; background: var(--surface); color: var(--muted);
}
.lang-toggle svg { flex: none; margin-right: 4px; }
.header-nav .lang-option {
  padding: .22rem .6rem; border-radius: 999px; font-size: .78rem; font-weight: 600; line-height: 1.2;
  color: var(--muted); text-decoration: none; white-space: nowrap;
}
.header-nav a.lang-option:hover { color: var(--text); background: var(--surface-3); }
.header-nav .lang-option.is-current { background: var(--accent); color: var(--accent-ink); }
.lang-long { display: none; }
.logo { flex: none; }
.logo svg { flex: none; }
/* En pantallas estrechas la cabecera se queda con lo esencial: logo, «Rarezas» y el idioma */
@media (max-width: 539px) {
  .share-text { display: none; }
  .header-nav { gap: .7rem; }
  .header-nav .nav-extra { display: none; }
}

/* Aviso de idioma para quien llega con el navegador en otro idioma */
.lang-hint {
  display: flex; flex-wrap: wrap; align-items: center; justify-content: center; gap: .5rem .9rem;
  padding: .55rem var(--gutter); font-size: .9rem; text-align: center;
  background: var(--surface-2); border-bottom: 1px solid var(--line);
}
.lang-hint[hidden] { display: none; }
.lang-hint .btn { padding: .3rem .8rem; font-size: .85rem; text-decoration: none; }

/* Calculadora — aspecto noche (por defecto) */
.calc {
  --calc-gap: 6px;
  width: 100%; max-width: 400px; margin-inline: auto;
  padding: 12px; border-radius: 18px;
  background: var(--surface); border: 1px solid var(--line);
  box-shadow: 0 20px 50px -20px rgba(0, 0, 0, .7);
}
.calc-screen {
  position: relative;
  padding: 10px 14px; margin-bottom: 12px;
  border-radius: 10px; background: #05080c; border: 1px solid var(--line);
}
.calc-display {
  font-family: var(--mono); font-weight: 700; font-size: 1.85rem; line-height: 1.3;
  text-align: right; white-space: pre; overflow: hidden;
  font-variant-numeric: tabular-nums; color: var(--text);
  min-height: 1.3em;
}
.calc-display[data-long] { font-size: 1.3rem; line-height: 1.85; }
.calc-noscript { padding: .75rem; margin-bottom: 12px; border-radius: 10px; background: var(--surface-2); color: var(--muted); font-size: .9rem; }

.calc-keys { display: grid; grid-template-columns: repeat(5, 1fr); gap: var(--calc-gap); }
.calc-keys--func { padding-bottom: 12px; margin-bottom: 12px; border-bottom: 1px solid var(--line); }
.calc-keys--main .key--clear { grid-column-start: 3; }

.key {
  height: 50px; border-radius: 10px;
  font-family: var(--sans); font-weight: 600; font-size: 1.05rem;
  background: var(--surface-2); border: 1px solid var(--line);
  touch-action: manipulation; user-select: none; -webkit-user-select: none;
  -webkit-tap-highlight-color: transparent;
  transition: background-color .15s var(--ease-out), transform .08s var(--ease-out), border-color .15s var(--ease-out);
}
.key--func { height: 38px; font-size: .9rem; color: var(--key-func); }
.key--num { color: var(--key-num); font-size: 1.15rem; background: var(--surface-3); }
.key--op { color: var(--text); }
.key--eq { color: var(--key-eq); }
@media (hover: hover) { .key:hover { background: #2a3648; border-color: #34435a; } }
.key:active, .key.is-pressed { transform: scale(.95); background: #33415a; border-color: var(--accent); }

/* Calculadora — aspecto del examen: medidas y colores de la original */
.calc[data-skin="examen"] {
  --calc-gap: 4px;
  width: 298px; max-width: 100%; padding: 5px; border-radius: 0;
  background: #cccccc; border: 1px solid #000; box-shadow: none;
}
.calc[data-skin="examen"] .calc-screen {
  padding: 0 5px; margin-bottom: 8px; border-radius: 0;
  background: #fff; border: 1px solid #f00;
}
.calc[data-skin="examen"] .calc-display {
  font-family: Arial, Helvetica, sans-serif; font-size: 20px; line-height: 25px; min-height: 25px; color: #000;
}
.calc[data-skin="examen"] .calc-display[data-long] { font-size: 20px; line-height: 25px; }
.calc[data-skin="examen"] .calc-keys { grid-template-columns: repeat(5, 50px); justify-content: space-between; row-gap: 4px; }
.calc[data-skin="examen"] .calc-keys--func { padding-bottom: 8px; margin-bottom: 8px; border-bottom: 1px solid #999; }
.calc[data-skin="examen"] .key {
  height: 30px; border-radius: 0; font-family: Arial, Helvetica, sans-serif; font-size: 14px; font-weight: 700;
  background: #f5f5f5; border: 1px solid #000; transition: none;
}
.calc[data-skin="examen"] .key--func { height: 24px; color: #f00; }
.calc[data-skin="examen"] .key--num { color: #00f; }
.calc[data-skin="examen"] .key--op { color: #262626; }
.calc[data-skin="examen"] .key--eq { color: #f00; }
.calc[data-skin="examen"] .key:hover { background: #fff; }
.calc[data-skin="examen"] .key:active,
.calc[data-skin="examen"] .key.is-pressed { transform: none; background: #ddd; }

/* Ayudas al estudio: fórmula y avisos (ocultas en modo examen) */
/* La calculadora y sus ayudas forman una columna. En móvil la fórmula sube ENCIMA de la pantalla (es donde se mira al
   teclear) con altura FIJA de una línea: si creciera, movería las teclas bajo el dedo. Fichas y avisos van siempre debajo. */
.practice { display: flex; flex-direction: column; }
.aids { width: 100%; max-width: 400px; margin: 10px auto 0; text-align: left; }
.aids--formula { order: -1; margin: 0 auto 10px; }
.aids--coach { margin-top: 8px; }
.aids--coach:not(:has(.aid-chip:not([hidden]), .coach:not([hidden]), .history:not([hidden]))) { display: none; }
.aids[hidden] { display: none; }
.formula {
  display: flex; align-items: center; gap: .6rem; height: 2.5rem;
  padding: 0 .75rem; border-radius: 10px;
  background: var(--surface); border: 1px solid var(--line);
}
.aids[data-alert] .formula { border-color: rgba(242, 184, 75, .6); }
.formula-label { flex: none; font-size: .68rem; font-weight: 600; letter-spacing: .06em; text-transform: uppercase; color: var(--muted); }
.formula-text {
  flex: 1; min-width: 0; font-family: var(--mono); font-size: .95rem; color: var(--text);
  white-space: nowrap; overflow-x: auto; scrollbar-width: none;
}
.formula-text::-webkit-scrollbar { display: none; }
.formula-text[data-empty] { font-family: var(--sans); font-size: .78rem; color: var(--muted); overflow: hidden; text-overflow: ellipsis; }
/* Indicadores de ayuda (memoria y paréntesis): fuera de la pantalla de la calculadora, que es como la del examen */
.aid-flags { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 6px; }
.aid-flags:not(:has(.aid-chip:not([hidden]))) { display: none; }
.aid-chip { padding: .18rem .6rem; border-radius: 999px; font-size: .76rem; color: var(--muted); background: var(--surface); border: 1px solid var(--line); }
.aid-chip strong { color: var(--accent); font-family: var(--mono); }
.aid-chip[hidden] { display: none; }
/* Compartir la secuencia: dentro de la fila de la fórmula, así no cambia la altura de nada */
.share-btn {
  flex: none; display: inline-flex; align-items: center; gap: .3rem; padding: .2rem .55rem; border-radius: 999px;
  font-size: .74rem; font-weight: 600; color: var(--accent); border: 1px solid rgba(242, 184, 75, .45); background: rgba(242, 184, 75, .07);
}
.share-btn:hover { background: rgba(242, 184, 75, .16); }
.share-btn[hidden] { display: none; }
/* Historial de operaciones */
.history { margin-top: 8px; padding: .6rem .75rem; border-radius: 10px; background: var(--surface); border: 1px solid var(--line); }
.history[hidden] { display: none; }
.history-title { margin-bottom: .35rem; font-size: .68rem; font-weight: 600; letter-spacing: .06em; text-transform: uppercase; color: var(--muted); }
.history-list { list-style: none; padding: 0; display: grid; gap: .25rem; font-family: var(--mono); font-size: .86rem; color: var(--muted); }
.history-list li { overflow-wrap: anywhere; }
.history-list li:first-child { color: var(--text); }
.coach { display: grid; gap: 6px; margin-top: 6px; }
.coach-item {
  padding: .6rem .75rem .6rem 2.1rem; border-radius: 10px; font-size: .86rem; line-height: 1.45;
  background: var(--surface); border: 1px solid var(--line); color: var(--text); position: relative;
}
.coach-item::before {
  content: "i"; position: absolute; left: .7rem; top: .68rem; width: 1rem; height: 1rem; border-radius: 50%;
  display: grid; place-items: center; font: 700 .68rem/1 var(--mono); color: var(--bg); background: var(--key-num);
}
.coach-item[data-kind="warn"] { border-color: rgba(242, 184, 75, .45); background: rgba(242, 184, 75, .07); }
.coach-item[data-kind="warn"]::before { content: "!"; background: var(--accent); }

/* Interruptores */
.options { display: flex; flex-wrap: wrap; gap: 10px 20px; justify-content: center; margin-top: 14px; }
.options .switch { text-align: left; }
.switch { display: inline-flex; align-items: center; gap: .6rem; cursor: pointer; font-size: .9rem; }
.switch input { position: absolute; opacity: 0; width: 1px; height: 1px; }
.switch-track {
  flex: none; width: 38px; height: 22px; border-radius: 999px; position: relative;
  background: var(--surface-3); border: 1px solid var(--line); transition: background-color .2s var(--ease-out);
}
.switch-track::after {
  content: ""; position: absolute; top: 2px; left: 2px; width: 16px; height: 16px; border-radius: 50%;
  background: var(--muted); transition: transform .2s var(--ease-out), background-color .2s var(--ease-out);
}
.switch input:checked + .switch-track { background: var(--accent); border-color: var(--accent); }
.switch input:checked + .switch-track::after { transform: translateX(16px); background: var(--accent-ink); }
.switch:has(input:disabled) { opacity: .45; cursor: default; }
.switch input:focus-visible + .switch-track { outline: 2px solid var(--accent); outline-offset: 2px; }
.switch-text { line-height: 1.25; }
.switch-text small { display: block; font-size: .75rem; color: var(--muted); }

/* Aviso del modo examen: solo donde hace falta (pantalla estrecha o pantalla táctil) */
.exam-note { display: none; max-width: 400px; margin: 12px auto 0; padding: .55rem .75rem; border-radius: 10px; font-size: .84rem; text-align: left;
  color: var(--text); background: rgba(242, 184, 75, .07); border: 1px solid rgba(242, 184, 75, .45); }
@media (max-width: 719px), (pointer: coarse) { .exam-note:not([hidden]) { display: block; } }

.privacy-badge {
  display: flex; align-items: flex-start; justify-content: center; gap: .45rem;
  max-width: 520px; margin: 16px auto 0; font-size: .8rem; color: var(--muted); text-align: left;
}
.privacy-badge svg { flex: none; margin-top: .15rem; color: var(--good); }

/* Anuncios oficiales de AdSense. Reglas: etiqueta «Anuncios» encima, altura reservada para que la página no salte,
   mucho aire alrededor (nunca a menos de 150 px de un botón) y un aspecto que NO imite nuestras tarjetas. */
.ad-wrap { padding-block: 96px; }
.ad-wrap[hidden] { display: none; }
.ad-unit { width: 100%; max-width: 728px; margin-inline: auto; }
.ad-label { margin-bottom: 6px; font-size: .68rem; letter-spacing: .08em; text-transform: uppercase; color: var(--muted); text-align: center; }
.ad-box { min-height: 280px; }                       /* adaptable en móvil: suele ocupar hasta 280 px */
/* Mientras AdSense no está activado, el hueco se ve marcado para poder revisar su posición */
.ad-box--pendiente { border: 1px dashed #3a4a61; border-radius: 4px; }
.hint-close {
  flex: none; width: 28px; height: 28px; border-radius: 50%; font-size: 1.15rem; line-height: 1;
  color: var(--text); background: var(--surface-3); border: 1px solid var(--line);
}
.hint-close:hover { border-color: var(--accent); color: var(--accent); }

/* Botones de contenido */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: .55rem .95rem; border-radius: 10px; font-weight: 600; font-size: .9rem;
  background: var(--accent); color: var(--accent-ink); border: 1px solid var(--accent);
  transition: filter .2s var(--ease-out), background-color .2s var(--ease-out);
}
.btn:hover { filter: brightness(1.08); }
.btn--ghost { background: transparent; color: var(--text); border-color: var(--line); }
.btn--ghost:hover { background: var(--surface-2); filter: none; }
.btn[disabled] { opacity: .5; cursor: default; }

/* =============================================================
   6. Sections
   ============================================================= */
.tool-section { padding-top: 14px; padding-bottom: 28px; text-align: center; }
.subtitle { color: var(--muted); font-size: .92rem; margin: .3rem auto 8px; max-width: 46ch; }
.seal { margin: 0 auto 12px; font-size: .8rem; }
.seal a {
  display: inline-flex; align-items: center; gap: .35rem; padding: .2rem .65rem .2rem .5rem; border-radius: 999px;
  color: var(--good); text-decoration: none; border: 1px solid rgba(126, 226, 168, .35); background: rgba(126, 226, 168, .07);
  transition: background-color .2s var(--ease-out);
}
.seal a:hover { background: rgba(126, 226, 168, .14); }
.seal svg { flex: none; }
.only-wide { display: none; }

.content { padding-block: 32px; border-top: 1px solid var(--line); }
.lead { color: var(--muted); max-width: 65ch; margin-bottom: 1.25rem; }

.steps { list-style: none; padding: 0; display: grid; gap: 14px; }
.steps li { padding: 18px; border-radius: var(--radius); background: var(--surface); border: 1px solid var(--line); }
.steps svg { color: var(--accent); margin-bottom: .6rem; }
.steps h3 { margin-bottom: .3rem; }
.steps p { color: var(--muted); font-size: .94rem; }
.steps strong { color: var(--text); }

.quirks { display: grid; gap: 14px; }
.quirk { display: flex; flex-direction: column; padding: 20px; border-radius: var(--radius); background: var(--surface); border: 1px solid var(--line); }
.quirk h3, .quirk h4 { margin-bottom: .5rem; font-size: 1.02rem; font-weight: 600; line-height: 1.3; }
.quirk-group { margin: 1.8rem 0 .9rem; color: var(--accent); font-size: .8rem; letter-spacing: .07em; text-transform: uppercase; }
.quirk-example { line-height: 1.9; }
.quirk-list button { margin-top: .2rem; }
.quirk-list details p:last-child { padding-bottom: 1rem; }
.quirk-note { margin-top: 1rem; font-size: .85rem; }
.quirk p { color: var(--muted); font-size: .94rem; margin-bottom: .7rem; }
.quirk p strong { color: var(--text); }
.quirk-example { padding: .7rem .85rem; border-radius: 10px; background: #05080c; border: 1px solid var(--line); }
.quirk .bad { color: var(--bad); font-family: var(--mono); }
.quirk-actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: auto; padding-top: .3rem; }

.prose p, .prose ul { color: var(--muted); max-width: 70ch; margin-bottom: 1rem; }
.prose h3 { margin: 1.6rem 0 .6rem; }
.prose ul { padding-left: 1.15rem; display: grid; gap: .55rem; }
.prose strong { color: var(--text); }

.faq { display: grid; gap: 8px; }
.faq details { border-radius: 12px; background: var(--surface); border: 1px solid var(--line); }
.faq summary { padding: .9rem 1rem; font-weight: 600; cursor: pointer; list-style: none; display: flex; justify-content: space-between; gap: 1rem; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--accent); font-family: var(--mono); flex: none; }
.faq details[open] summary::after { content: "–"; }
.fuentes-titulo { margin: 1.6rem 0 .6rem; }
.fuentes { padding-left: 1.15rem; display: grid; gap: .45rem; color: var(--muted); font-size: .93rem; max-width: 75ch; }
.fuentes a, .steps a, .prose a, .faq a, .quirk-note a { color: var(--text); overflow-wrap: anywhere; }
.faq details p { padding: 0 1rem 1rem; color: var(--muted); font-size: .95rem; max-width: 70ch; }

.site-footer { border-top: 1px solid var(--line); padding-block: 28px 40px; font-size: .88rem; }
.footer-inner { display: grid; gap: .6rem; }
.footer-links a { color: var(--muted); }
.footer-links a:hover { color: var(--text); }

/* Páginas legales */
.legal { padding-block: 32px 48px; }
.legal h1 { margin-bottom: 1rem; }
.legal h2 { font-size: 1.15rem; margin-top: 1.6rem; }
.legal p, .legal li { color: var(--muted); max-width: 70ch; margin-bottom: .8rem; }
.legal .todo { color: var(--accent); }
.legal a { overflow-wrap: anywhere; }
.legal ul { padding-left: 1.15rem; }
.legal strong { color: var(--text); }
.legal a { color: var(--text); }

/* Modo entrenamiento */
.training-page h1 { margin-bottom: 12px; }
.training-page .history { display: none; }            /* aquí manda el resultado del ejercicio, no el historial */
.training-page .options { margin-top: 22px; }
.training-head {
  max-width: 400px; margin: 0 auto 10px; padding: .6rem .8rem; text-align: left; border-radius: 12px;
  background: var(--surface); border: 1px solid rgba(242, 184, 75, .45);
  height: 7.4rem; overflow-y: auto;                     /* altura fija: las teclas no se mueven al cambiar de ejercicio */
}
.training-count { font-size: .68rem; font-weight: 600; letter-spacing: .06em; text-transform: uppercase; color: var(--accent); min-height: 1em; }
.training-title { font-size: 1rem !important; margin: .1rem 0 .25rem !important; }
.training-text { font-size: .92rem; color: var(--text); }
.training-controls { max-width: 400px; margin: 10px auto 0; text-align: left; }
.training-stats { font-family: var(--mono); font-size: .8rem; color: var(--muted); min-height: 1.3em; }
.training-feedback { margin-top: 6px; padding: .6rem .75rem; border-radius: 10px; font-size: .9rem; background: var(--surface); border: 1px solid var(--line); }
.training-feedback[hidden], .training-formula[hidden] { display: none; }
.training-feedback[data-kind="ok"] { border-color: rgba(126, 226, 168, .5); background: rgba(126, 226, 168, .08); }
.training-feedback[data-kind="warn"] { border-color: rgba(242, 184, 75, .5); background: rgba(242, 184, 75, .07); }
.training-formula { margin-top: 6px; padding: .5rem .75rem; border-radius: 10px; font-family: var(--mono); font-size: .84rem; color: var(--text); background: #05080c; border: 1px solid var(--line); }
.training-buttons { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 10px; }
.training-buttons .btn[hidden] { display: none; }
@media (min-width: 720px) { .training-head { height: auto; min-height: 6.2rem; } }

/* Página de ejemplos resueltos */
.ejemplos-pagina h2 { margin-top: 2.2rem !important; color: var(--accent); font-size: .85rem !important; letter-spacing: .07em; text-transform: uppercase; }
.ejemplos { display: grid; gap: 12px; margin-top: .8rem; }
.ejemplo { padding: 18px; border-radius: var(--radius); background: var(--surface); border: 1px solid var(--line); }
.ejemplo--trampa { border-color: rgba(242, 184, 75, .45); background: rgba(242, 184, 75, .05); }
.ejemplo h3 { margin-bottom: .4rem; font-size: 1.02rem; }
.ejemplo p { margin-bottom: .6rem; max-width: none; }
.ejemplo-formula code { font-family: var(--mono); font-size: .88rem; color: var(--text); }
.ejemplo dl { display: grid; grid-template-columns: auto 1fr; gap: .45rem .9rem; margin: .8rem 0; font-size: .92rem; align-items: baseline; }
.ejemplo dt { color: var(--muted); font-size: .72rem; letter-spacing: .06em; text-transform: uppercase; }
.ejemplo dd { margin: 0; color: var(--muted); min-width: 0; }
.ejemplo dd .seq { white-space: normal; line-height: 1.9; }
.ejemplo .ok { color: var(--good); font-family: var(--mono); font-size: 1.05em; }
.ejemplo .bad { color: var(--bad); font-family: var(--mono); font-size: 1.05em; }
.ejemplo-acciones { display: flex; flex-wrap: wrap; gap: 8px; margin: 0 !important; }
.ejemplo-acciones .btn { text-decoration: none; }

/* Hoja de reglas de oro (pensada para imprimirse en una sola página) */
.hoja h1 { margin-bottom: .5rem; }
.hoja-intro { max-width: 70ch; }
.reglas { list-style: none; padding: 0; display: grid; gap: 10px; margin-top: 1rem; }
.regla { padding: 12px 14px; border-radius: 12px; background: var(--surface); border: 1px solid var(--line); margin: 0 !important; max-width: none !important; }
.regla h2 { font-size: 1rem !important; margin: 0 0 .4rem !important; color: var(--text); }
.regla-linea { margin: .15rem 0 !important; max-width: none !important; font-size: .9rem; }
.regla-linea code, .hoja-trucos code { font-family: var(--mono); color: var(--text); }
.regla-tag { display: inline-block; min-width: 4.6em; font-size: .68rem; font-weight: 700; letter-spacing: .05em; text-transform: uppercase; }
.regla-tag--mal { color: var(--bad); }
.regla-tag--bien { color: var(--good); }
.regla-res { color: var(--muted); }
.hoja-sub { margin-top: 1.4rem !important; }
.hoja-trucos { padding-left: 1.15rem; }
.hoja-pie { margin-top: 1.2rem; font-size: .82rem; }
@media (min-width: 720px) { .reglas { grid-template-columns: 1fr 1fr; } }
@media print {
  @page { size: A4; margin: 12mm; }
  html, body { background: #fff !important; color: #000 !important; font-size: 11pt; }
  .site-header, .site-footer, .no-print, .ad-wrap, .lang-hint { display: none !important; }
  .hoja { padding: 0 !important; max-width: none !important; }
  .hoja h1 { font-size: 17pt; color: #000; }
  .hoja p, .hoja li, .hoja-intro, .hoja strong { color: #000 !important; }
  .reglas { grid-template-columns: 1fr 1fr; gap: 5pt; }
  .regla { background: #fff !important; border: 0.6pt solid #666 !important; border-radius: 4pt; padding: 5pt 7pt; break-inside: avoid; }
  .regla h2 { font-size: 10.5pt !important; color: #000 !important; }
  .regla-linea { font-size: 9.5pt; }
  .regla-linea code, .hoja-trucos code { color: #000 !important; }
  .regla-tag--mal { color: #b00020 !important; } .regla-tag--bien { color: #0a6b2d !important; } .regla-res { color: #333 !important; }
  .hoja-pie { color: #333 !important; font-size: 8.5pt; }
}

/* Página de verificación */
.verif-cifra { font-size: 1.15rem; color: var(--text) !important; max-width: none !important; }
.verif-cifra strong { font-family: var(--mono); font-size: 1.5em; margin-right: .2em; }
.verif .si, .verif-tabla .si { color: var(--good); }
.verif .no, .verif-tabla .no { color: var(--bad); font-weight: 700; }
.tabla-scroll { overflow-x: auto; margin-bottom: 1rem; border: 1px solid var(--line); border-radius: 12px; }
.verif-tabla { width: 100%; border-collapse: collapse; font-size: .85rem; }
.verif-tabla th, .verif-tabla td { padding: .5rem .75rem; text-align: left; border-bottom: 1px solid var(--line); vertical-align: top; }
.verif-tabla thead th { position: sticky; top: 0; background: var(--surface-2); color: var(--muted); font-weight: 600; font-size: .75rem; letter-spacing: .05em; text-transform: uppercase; }
.verif-tabla tbody tr:last-child td { border-bottom: 0; }
.verif-tabla code { font-family: var(--mono); font-size: .92em; white-space: pre; color: var(--text); }
.verif-tabla td:first-child code { white-space: normal; color: var(--accent); }
.verif-resumen td:last-child, .verif-resumen th:last-child { text-align: right; font-family: var(--mono); white-space: nowrap; }
.verif-grupo { margin-bottom: 8px; border-radius: 12px; background: var(--surface); border: 1px solid var(--line); }
.verif-grupo summary { display: flex; justify-content: space-between; gap: 1rem; padding: .9rem 1rem; font-weight: 600; cursor: pointer; list-style: none; }
.verif-grupo summary::-webkit-details-marker { display: none; }
.verif-cuenta { font-family: var(--mono); color: var(--good); white-space: nowrap; }
.verif-grupo > p { padding: 0 1rem; }
.verif-grupo .tabla-scroll { margin: 0 1rem 1rem; max-height: 60vh; overflow-y: auto; }

.glosario td:first-child { white-space: nowrap; color: var(--accent); font-family: var(--mono); }
.glosario td { color: var(--muted); }
.glosario code { white-space: normal; }
.lead a { color: var(--text); }

/* =============================================================
   8. Responsive (mobile-first)
   ============================================================= */
@media (min-width: 540px) {
  :root { --gutter: 24px; }
  .only-wide { display: inline; }
  .key { height: 52px; }
  .key--func { height: 40px; }
}
@media (min-width: 720px) {
  .aids--formula { order: 0; margin: 10px auto 0; }
  .formula { height: auto; min-height: 2.6rem; padding-block: .55rem; align-items: baseline; }
  .formula-text { white-space: normal; overflow-wrap: anywhere; overflow: visible; }
  .lang-long { display: inline; }
  .lang-short { display: none; }
  .tool-section { padding-top: 24px; padding-bottom: 40px; }
  .ad-box { min-height: 120px; }
  .subtitle { margin-bottom: 10px; font-size: 1rem; }
  .seal { margin-bottom: 18px; font-size: .85rem; }
  .steps { grid-template-columns: repeat(3, 1fr); }
  .quirks { grid-template-columns: repeat(2, 1fr); }
  .ejemplos { grid-template-columns: repeat(2, 1fr); }
  .content { padding-block: 48px; }
  .header-inner { height: 56px; }
}

/* Pantallas bajas (portátiles pequeños): la calculadora siempre entera a la vista */
@media (max-height: 760px) and (min-width: 540px) {
  .key { height: 44px; }
  .key--func { height: 34px; }
}

/* =============================================================
   9. Reduced motion
   ============================================================= */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}