:root {
  --ink: #10141c;
  --ink-2: #171d29;
  --ink-3: #1e2532;
  --line: #2a3242;
  --brass: #d4a72c;
  --brass-dim: #a5842a;
  --teal: #5fb3a3;
  --text: #eef1f6;
  --text-muted: #8b93a3;
  --danger: #e0725f;
  --radius: 10px;
  --font-display: 'Space Grotesk', 'Inter', sans-serif;
  --font-body: 'Inter', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--ink);
  color: var(--text);
  font-family: var(--font-body);
  min-height: 100vh;
}

.page {
  max-width: 980px;
  margin: 0 auto;
  padding: 32px 20px 80px;
}

/* ---------- HEADER ---------- */
.site-brand {
  display: inline-flex;
  align-items: baseline;
  gap: 4px;
  font-family: var(--font-display);
  font-size: 28px;
  font-weight: 700;
  color: var(--text-muted);
  text-decoration: none;
  margin-bottom: 18px;
}
.site-brand span { color: var(--brass); }
.site-brand:hover { color: var(--text); }
.site-header {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 4px;
  margin-bottom: 28px;
  flex-wrap: wrap;
}
.site-title {
  font-family: var(--font-display);
  font-size: 28px;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 0;
}
.site-title span { color: var(--brass); }
.site-sub {
  color: var(--text-muted);
  font-size: 13px;
  margin: 4px 0 0;
}

/* ---------- SMART BAR (elemento firma: cinta métrica) ---------- */
.smart-bar {
  position: relative;
  background: var(--ink-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px 22px 16px;
  margin-bottom: 28px;
  overflow: hidden;
}
.tape-ticks {
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 8px;
  background-image: repeating-linear-gradient(
    90deg,
    var(--brass) 0px, var(--brass) 1px,
    transparent 1px, transparent 12px
  );
  opacity: 0.55;
}
.tape-ticks::after {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0; height: 8px;
  background-image: repeating-linear-gradient(
    90deg,
    var(--brass) 0px, var(--brass) 2px,
    transparent 2px, transparent 60px
  );
  opacity: 0.9;
}
#smartInput {
  width: 100%;
  background: transparent;
  border: none;
  border-bottom: 1px dashed var(--line);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 20px;
  padding: 14px 4px 12px 0;
  outline: none;
  margin-top: 10px;
}
#smartInput::placeholder { color: var(--text-muted); }
#smartResult {
  min-height: 34px;
  margin-top: 14px;
  font-family: var(--font-mono);
  font-size: 22px;
}
.result-value { color: var(--brass); font-weight: 700; font-size: 1.5em; }
.result-unit { color: var(--text-muted); font-size: 15px; margin-left: 6px; }
.hint { color: var(--text-muted); font-size: 14px; font-family: var(--font-body); }
.hint em { color: var(--teal); font-style: normal; }
.hint-warn { color: var(--danger); }
#smartTape {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 10px;
}
.tape-chip {
  background: var(--ink-3);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 5px 12px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: var(--text-muted);
}
.tape-eq {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--text-muted);
}

/* ---------- TABS ---------- */
#tabNav {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 20px;
}
.tab-btn {
  background: var(--ink-2);
  border: 1px solid var(--line);
  color: var(--text-muted);
  font-family: var(--font-body);
  font-size: 13px;
  padding: 8px 12px;
  border-radius: 999px;
  cursor: pointer;
  transition: all 0.15s ease;
  white-space: nowrap;
}
.tab-btn:hover { border-color: var(--brass-dim); color: var(--text); }
.tab-btn.active {
  background: var(--brass);
  border-color: var(--brass);
  color: var(--ink);
  font-weight: 600;
}

/* ---------- PANEL AREA ---------- */
#panelArea {
  background: var(--ink-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
}
.panel-note {
  color: var(--text-muted);
  font-size: 12.5px;
  margin: 0 0 16px;
  line-height: 1.5;
}
.panel-result {
  font-family: var(--font-mono);
  color: var(--brass);
  font-size: 16px;
  margin: 4px 0 18px;
}

.convert-row {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 14px;
  align-items: center;
  margin-bottom: 22px;
}
.convert-col { display: flex; flex-direction: column; gap: 8px; }
.num-input, .text-input, .date-input {
  background: var(--ink-3);
  border: 1px solid var(--line);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 18px;
  padding: 10px 12px;
  border-radius: 8px;
  width: 100%;
  outline: none;
}
.num-input:focus, .text-input:focus, .date-input:focus { border-color: var(--brass-dim); }
.num-input:disabled { color: var(--teal); }
.unit-select {
  background: var(--ink-3);
  border: 1px solid var(--line);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 13px;
  padding: 8px 10px;
  border-radius: 8px;
  outline: none;
}
.swap-btn {
  background: var(--ink-3);
  border: 1px solid var(--line);
  color: var(--brass);
  font-size: 18px;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  cursor: pointer;
  align-self: center;
}
.swap-btn:hover { border-color: var(--brass); }
.swap-static {
  align-self: center;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: 20px;
  text-align: center;
}

.quick-table {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: 10px;
}
.quick-item {
  background: var(--ink-3);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 10px 12px;
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.quick-label { font-size: 11.5px; color: var(--text-muted); }
.quick-value { font-family: var(--font-mono); font-size: 15px; color: var(--text); }

h4 {
  font-family: var(--font-display);
  font-size: 14px;
  color: var(--teal);
  margin: 22px 0 12px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}
h4:first-child { margin-top: 0; }

.calc-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 16px;
}
.calc-card {
  background: var(--ink-3);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 16px;
}
.calc-card h4 { margin-top: 0; }
.calc-row-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
  gap: 10px;
  margin-bottom: 8px;
}
.labeled-input { display: flex; flex-direction: column; gap: 6px; }
.labeled-input label { font-size: 11px; color: var(--text-muted); }

.ref-table { margin-top: 6px; }
.ref-row {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr 1fr;
  gap: 8px;
  padding: 8px 0;
  border-bottom: 1px solid var(--line);
  font-size: 13px;
}
.ref-head { color: var(--teal); font-weight: 600; font-size: 11.5px; text-transform: uppercase; }

footer.site-footer {
  text-align: center;
  color: var(--text-muted);
  font-size: 12px;
  margin-top: 32px;
}
footer.site-footer a { color: var(--text-muted); text-decoration: none; }
footer.site-footer a:hover { color: var(--teal); text-decoration: underline; }

/* ---------- Ejemplos comunes (por par de conversión) ---------- */
.examples-list { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 10px; }
.examples-list li {
  font-family: var(--font-mono); font-size: 13.5px; color: var(--text);
  background: var(--ink-2); border: 1px solid var(--line); border-radius: 8px; padding: 10px 14px;
}
.example-note { font-family: var(--font-body); color: var(--text-muted); font-size: 12.5px; }

/* ---------- Páginas estáticas (Acerca de, Contacto, Privacidad) ---------- */
ul.plain-list { margin: 0 0 16px; padding-left: 20px; color: var(--text); font-size: 14.5px; line-height: 1.75; max-width: 68ch; }
ul.plain-list li { margin-bottom: 6px; }
a.inline-link { color: var(--teal); text-decoration: none; }
a.inline-link:hover { text-decoration: underline; }

@media (max-width: 600px) {
  .convert-row { grid-template-columns: 1fr; }
  .swap-btn { justify-self: center; }
  .ref-row { grid-template-columns: 1fr 1fr 1fr 1fr; font-size: 11px; }

  /* En móvil, el menú de categorías pasa a una sola fila deslizable en vez de
     envolver en varias filas: así no empuja la calculadora fuera de la
     pantalla inicial. La versión de escritorio (arriba) no se toca. */
  #tabNav {
    flex-wrap: nowrap;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    padding-bottom: 2px;
    margin-left: -4px;
    margin-right: -4px;
    padding-left: 4px;
    padding-right: 4px;
    mask-image: linear-gradient(to right, transparent 0, #000 4px, #000 calc(100% - 16px), transparent 100%);
  }
  #tabNav::-webkit-scrollbar { display: none; }
  .tab-btn { flex: 0 0 auto; }

  /* Versión compacta de la barra de búsqueda cuando va arriba, para que no
     empuje la calculadora fuera de la pantalla inicial en móvil. */
  .smart-bar-compact {
    padding: 14px 14px 10px;
    margin-bottom: 14px;
  }
  .smart-bar-compact #smartInput {
    font-size: 15px;
    margin-top: 6px;
    padding: 8px 2px 8px 0;
  }
  .smart-bar-compact #smartResult {
    min-height: 0;
    margin-top: 6px;
    font-size: 17px;
  }
  .smart-bar-compact #smartTape { margin-top: 6px; }
}
/* ---------- Extra: páginas SEO individuales (mismo sistema de diseño) ---------- */
.breadcrumb { font-size: 12.5px; color: var(--text-muted); margin-bottom: 10px; }
.breadcrumb a { color: var(--teal); text-decoration: none; }
.breadcrumb a:hover { text-decoration: underline; }
.breadcrumb span { color: var(--text-muted); }

/* ---------- Tabla de contenidos ---------- */
.toc {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 20px 0 32px;
  padding: 14px 16px;
  background: var(--ink-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}
.toc a {
  font-size: 12.5px;
  color: var(--text-muted);
  text-decoration: none;
  padding: 5px 11px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: var(--ink-3);
}
.toc a:hover { color: var(--text); border-color: var(--brass-dim); }

/* ---------- Secciones de contenido (más aire entre bloques) ---------- */
.content-section {
  margin: 0 0 40px;
  scroll-margin-top: 24px;
}
.content-section:last-of-type { margin-bottom: 28px; }
.section-title {
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  color: var(--text);
  margin: 0 0 16px;
}
.seo-intro {
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--text);
  margin: 0 0 20px;
  max-width: 68ch;
}
.seo-intro em { color: var(--text-muted); font-style: normal; }

/* ---------- Caja de fórmula destacada ---------- */
.formula-box {
  background: var(--ink-2);
  border: 1px solid var(--brass-dim);
  border-left: 3px solid var(--brass);
  border-radius: 8px;
  padding: 14px 18px;
  margin: 0 0 22px;
  max-width: 420px;
}
.formula-label {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--teal);
  margin: 0 0 6px;
}
.formula-text {
  font-family: var(--font-mono);
  font-size: 17px;
  color: var(--brass);
  margin: 0;
  font-weight: 600;
}

/* ---------- Caja de búsquedas populares (valores puntuales con demanda real) ---------- */
.popular-box {
  background: var(--ink-2);
  border: 1px solid var(--brass-dim);
  border-left: 3px solid var(--teal);
  border-radius: 8px;
  padding: 14px 18px;
  margin: 0 0 22px;
  max-width: 420px;
}
.popular-label {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--teal);
  margin: 0 0 8px;
}
.popular-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.popular-list li {
  font-family: var(--font-mono);
  font-size: 14.5px;
  color: var(--text);
}
.popular-list strong { color: var(--brass); }

/* ---------- Bloque "Aprende más" ---------- */
.learn-p {
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--text);
  margin: 0 0 16px;
  max-width: 68ch;
}
.learn-p strong { color: var(--brass); }
.learn-p.seo-about {
  color: var(--text-muted);
  font-size: 13.5px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
}

.seo-table { width: 100%; border-collapse: collapse; max-width: 420px; }
.seo-table td { padding: 8px 10px; border-bottom: 1px solid var(--line); font-family: var(--font-mono); font-size: 14px; }
.seo-table td:first-child { color: var(--text-muted); }
.seo-table tr:last-child td { border-bottom: none; }
.related-links { display: flex; flex-wrap: wrap; gap: 8px; margin: 24px 0 8px; }
.related-links a {
  background: var(--ink-2); border: 1px solid var(--line); color: var(--text-muted);
  border-radius: 999px; padding: 6px 12px; font-size: 12.5px; text-decoration: none;
}
.related-links a:hover { border-color: var(--brass-dim); color: var(--text); }
.related-label { font-size: 11.5px; color: var(--teal); text-transform: uppercase; letter-spacing: 0.04em; margin: 18px 0 8px; }
.related-links-cross a { border-style: dashed; }
.faq-block { margin-top: 8px; }
.faq-title { font-family: var(--font-display); font-size: 15px; color: var(--text); margin: 0 0 12px; }
.faq-item { border-top: 1px solid var(--line); padding: 12px 0; }
.faq-item:first-of-type { border-top: none; padding-top: 0; }
.faq-q { font-weight: 600; font-size: 14px; color: var(--text); margin: 0 0 6px; }
.faq-a { font-size: 13.5px; color: var(--text-muted); line-height: 1.6; margin: 0; max-width: 68ch; }
.faq-a a { color: var(--teal); text-decoration: none; }
.faq-a a:hover { text-decoration: underline; }

/* ---------- Grilla de categorías (home) ---------- */
.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 12px;
}
.category-card {
  display: block;
  background: var(--ink-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 14px 16px;
  text-decoration: none;
  transition: border-color 0.15s ease;
}
.category-card:hover { border-color: var(--brass-dim); }
.category-card h3 {
  font-family: var(--font-display);
  font-size: 14.5px;
  font-weight: 700;
  color: var(--text);
  margin: 0 0 6px;
}
.category-card p {
  font-size: 12.5px;
  line-height: 1.55;
  color: var(--text-muted);
  margin: 0;
}