/* Calculario — una herramienta por página, contenido de lectura debajo; la hoja de calendario es el motivo */
:root {
  --bg: #F2F4F6;
  --surface: #FFFFFF;
  --ink: #15202A;
  --muted: #56646F;
  --line: #D6DCE1;
  --accent: #C23A22;      /* rojo de hoja de calendario */
  --accent-ink: #FFFFFF;
  --field: #F8FAFB;
  --focus: #1D6FD6;
  --font-display: "Bricolage Grotesque", "Segoe UI", system-ui, sans-serif;
  --font-body: "Source Sans 3", "Segoe UI", system-ui, sans-serif;
  --font-num: "IBM Plex Mono", ui-monospace, "SFMono-Regular", Menlo, monospace;
  --radius: 10px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0F151B; --surface: #172028; --ink: #E5EBEF; --muted: #97A5B0; --line: #2B3843;
    --accent: #EE6A50; --accent-ink: #1A0D09; --field: #121A21; --focus: #7FB2FF; color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #0F151B; --surface: #172028; --ink: #E5EBEF; --muted: #97A5B0; --line: #2B3843;
  --accent: #EE6A50; --accent-ink: #1A0D09; --field: #121A21; --focus: #7FB2FF; color-scheme: dark;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.6;
}
a { color: var(--ink); text-decoration-color: var(--accent); text-underline-offset: 3px; }
a:hover { color: var(--accent); }
:focus-visible { outline: 2px solid var(--focus); outline-offset: 2px; }
.wrap {
  max-width: 1040px;
  margin: 0 auto;
  padding-left: max(16px, env(safe-area-inset-left, 0px));
  padding-right: max(16px, env(safe-area-inset-right, 0px));
}

/* Cabecera */
.site-head { border-bottom: 1px solid var(--line); background: var(--surface); }
.site-head .wrap { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 12px; padding-block: 14px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-family: var(--font-display); font-weight: 700; font-size: 1.35rem; text-decoration: none; letter-spacing: -0.01em; }
.brand-mark { width: 26px; height: 28px; border-radius: 4px; border: 2px solid var(--ink); position: relative; overflow: hidden; background: var(--surface); }
.brand-mark::before { content: ""; position: absolute; inset: 0 0 auto; height: 8px; background: var(--accent); }
.brand-mark::after { content: "3"; position: absolute; inset: 8px 0 0; display: grid; place-items: center; font: 700 12px/1 var(--font-num); color: var(--ink); }
.nav { display: flex; flex-wrap: wrap; gap: 4px 18px; font-size: 0.95rem; }
.nav a { text-decoration: none; color: var(--muted); padding-block: 4px; border-bottom: 2px solid transparent; }
.nav a:hover, .nav a[aria-current="page"] { color: var(--ink); border-bottom-color: var(--accent); }

/* Títulos */
.hero { padding-block: 36px 20px; }
.eyebrow { font: 600 0.78rem/1 var(--font-num); letter-spacing: 0.12em; text-transform: uppercase; color: var(--accent); margin: 0 0 12px; }
h1, h2, h3 { font-family: var(--font-display); line-height: 1.15; text-wrap: balance; letter-spacing: -0.015em; }
h1 { font-size: clamp(2rem, 5vw, 3rem); margin: 0 0 12px; font-weight: 700; }
.lede { font-size: 1.15rem; color: var(--muted); max-width: 62ch; margin: 0; }

/* Herramienta */
.tool { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); margin-bottom: 28px; }
.tabs { display: flex; flex-wrap: wrap; border-bottom: 1px solid var(--line); padding-inline: 8px; }
.tabs [role="tab"] {
  appearance: none; background: none; border: 0; border-bottom: 3px solid transparent; margin-bottom: -1px;
  font: 600 1rem var(--font-body); color: var(--muted); padding: 14px 14px 11px; cursor: pointer;
}
.tabs [role="tab"][aria-selected="true"] { color: var(--ink); border-bottom-color: var(--accent); }
.panel { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 6fr); }
.panel[hidden] { display: none; }
.inputs { padding: 22px; border-right: 1px solid var(--line); display: grid; gap: 16px; align-content: start; }
.output { padding: 22px; min-width: 0; }
.field { display: grid; gap: 6px; }
.field label, .lbl { font-weight: 600; font-size: 0.92rem; }
.row2 { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
input[type="date"], input[type="text"], input[type="number"], select {
  width: 100%; min-width: 0; font: 500 1rem var(--font-body); color: var(--ink); background: var(--field);
  border: 1px solid var(--line); border-radius: 8px; padding: 10px 12px;
}
input.numeric { font-family: var(--font-num); font-variant-numeric: tabular-nums; }
.check { display: flex; gap: 10px; align-items: flex-start; font-size: 0.95rem; }
.check input { margin-top: 5px; accent-color: var(--accent); }
.hint { font-size: 0.86rem; color: var(--muted); margin: 0; }
button.btn {
  font: 600 0.95rem var(--font-body); color: var(--ink); background: var(--field); border: 1px solid var(--line);
  border-radius: 8px; padding: 9px 14px; cursor: pointer;
}
button.btn:hover:not(:disabled) { border-color: var(--ink); }
button:disabled { opacity: 0.45; cursor: not-allowed; }

/* Resultado */
.result-head { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; margin-bottom: 14px; }
.arrow { font: 600 1.4rem var(--font-num); color: var(--muted); }
.leaf {
  width: 104px; border: 1px solid var(--line); border-radius: 8px; overflow: hidden; background: var(--surface);
  display: grid; text-align: center; box-shadow: 0 1px 0 var(--line), 0 3px 0 -1px var(--surface), 0 4px 0 -1px var(--line);
}
.leaf-top { background: var(--accent); color: var(--accent-ink); font: 600 0.72rem/1 var(--font-num); letter-spacing: 0.08em; padding: 6px 4px; }
.leaf-day { font: 700 2.3rem/1.1 var(--font-display); padding-top: 6px; }
.leaf-wd { font-size: 0.8rem; color: var(--muted); padding-bottom: 4px; }
.leaf-label { font: 600 0.68rem/1 var(--font-num); letter-spacing: 0.1em; text-transform: uppercase; color: var(--muted); border-top: 1px dashed var(--line); padding: 6px 4px; }
.big { margin: 0 0 6px; font-size: 1.15rem; }
.big-num { font: 600 clamp(2.2rem, 6vw, 3.2rem)/1.1 var(--font-num); font-variant-numeric: tabular-nums; letter-spacing: -0.02em; }
.big-date { font: 700 1.6rem/1.25 var(--font-display); }
.stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); gap: 0 20px; margin: 14px 0 0; }
.stats div { border-top: 1px solid var(--line); padding-block: 10px; }
.stats dt { font-size: 0.82rem; color: var(--muted); }
.stats dd { margin: 0; font-weight: 600; font-variant-numeric: tabular-nums; }
.stats dd a { font-weight: 400; font-size: 0.85rem; margin-left: 6px; }
.msg { color: var(--muted); margin: 8px 0 0; }
.note { font-size: 0.85rem; color: var(--muted); margin: 14px 0 0; border-left: 3px solid var(--line); padding-left: 10px; }
.sub { font-size: 1rem; margin: 20px 0 8px; }
.hol-list { list-style: none; margin: 0; padding: 0; display: grid; }
.hol-list li { display: flex; gap: 14px; padding: 7px 0; border-bottom: 1px solid var(--line); font-size: 0.95rem; }
.hol-date { font-family: var(--font-num); font-variant-numeric: tabular-nums; color: var(--accent); min-width: 7.5em; }
.hol-list em { color: var(--muted); font-style: normal; }
.steps { margin: 12px 0 0; padding-left: 1.3em; display: grid; gap: 4px; font-variant-numeric: tabular-nums; }

/* Regla de tres: esquema */
.r3-grid { display: grid; grid-template-columns: 1fr auto 1fr; gap: 10px; align-items: end; }
.r3-grid .to { font: 600 1.2rem var(--font-num); color: var(--muted); padding-bottom: 10px; }
.r3-x { font: 600 1.05rem var(--font-num); background: var(--field); border: 1px dashed var(--accent); border-radius: 8px; padding: 10px 12px; color: var(--accent); overflow-x: auto; white-space: nowrap; }
.rc-fila { display: grid; grid-template-columns: 1.3fr 1fr 1fr 1.2fr auto; gap: 8px; align-items: end; border-top: 1px dashed var(--line); padding-top: 12px; }
.rc-fila .field label { font-size: 0.8rem; color: var(--muted); }
.rc-quitar { align-self: end; padding: 10px 12px !important; }
#rc-filas { display: grid; gap: 12px; }

/* Contenido */
.content { display: grid; grid-template-columns: minmax(0, 68ch) minmax(0, 1fr); gap: 40px; padding-block: 8px 48px; }
.content article { min-width: 0; }
.content h2 { font-size: 1.55rem; margin: 32px 0 10px; }
.content h2:first-child { margin-top: 8px; }
.content h3 { font-size: 1.15rem; margin: 22px 0 6px; }
.content p, .content li { max-width: 68ch; }
.formula { font-family: var(--font-num); background: var(--surface); border: 1px solid var(--line); border-radius: 8px; padding: 12px 14px; overflow-x: auto; white-space: nowrap; font-size: 0.95rem; }
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: 8px; background: var(--surface); }
table { border-collapse: collapse; width: 100%; font-size: 0.95rem; }
th, td { text-align: left; padding: 9px 12px; border-bottom: 1px solid var(--line); vertical-align: top; }
th { font-family: var(--font-body); font-weight: 700; background: var(--field); }
td.n { font-family: var(--font-num); font-variant-numeric: tabular-nums; white-space: nowrap; }
details { border-bottom: 1px solid var(--line); padding-block: 12px; }
summary { cursor: pointer; font-weight: 600; }
details p { margin: 8px 0 0; }
.aside { min-width: 0; display: grid; gap: 18px; align-content: start; }
.aside-box { border-top: 3px solid var(--ink); padding-top: 12px; }
.aside-box h2 { font-size: 1rem !important; margin: 0 0 8px !important; }
.aside-box ul { margin: 0; padding-left: 1.1em; }
.ad-slot:empty { display: none; }
.ad-slot { margin-block: 20px; min-height: 90px; }

/* Inicio */
.cards { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; padding-bottom: 40px; }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; display: grid; gap: 8px; align-content: start; text-decoration: none; }
.card:hover { border-color: var(--ink); color: var(--ink); }
.card h2 { margin: 0; font-size: 1.3rem; }
.card p { margin: 0; color: var(--muted); }
.card .go { font: 600 0.8rem var(--font-num); color: var(--accent); letter-spacing: 0.06em; text-transform: uppercase; }

/* Pie */
.site-foot { border-top: 1px solid var(--line); background: var(--surface); font-size: 0.9rem; color: var(--muted); }
.site-foot .wrap { display: flex; flex-wrap: wrap; gap: 8px 24px; justify-content: space-between; padding-block: 22px; }
.site-foot nav { display: flex; flex-wrap: wrap; gap: 6px 16px; }
.site-foot a { color: var(--muted); }
.legal { padding-block: 32px 56px; max-width: 72ch; }
.legal h2 { font-size: 1.3rem; margin-top: 28px; }

@media (max-width: 820px) {
  .panel { grid-template-columns: minmax(0, 1fr); }
  .inputs { border-right: 0; border-bottom: 1px solid var(--line); }
  .content { grid-template-columns: minmax(0, 1fr); }
  .cards { grid-template-columns: minmax(0, 1fr); }
}
@media (max-width: 560px) {
  .rc-fila { grid-template-columns: 1fr 1fr; }
  .rc-fila .field:first-child { grid-column: 1 / -1; }
  .leaf { width: 88px; }
  .leaf-day { font-size: 1.9rem; }
  .row2 { grid-template-columns: minmax(0, 1fr); }
}
@media (prefers-reduced-motion: reduce) { * { scroll-behavior: auto !important; transition: none !important; } }

/* Cuenta regresiva */
.clock { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 10px; margin-bottom: 8px; }
.clock div { border: 1px solid var(--line); border-radius: 8px; overflow: hidden; text-align: center; background: var(--surface); display: grid; }
.clock div::before { content: ""; height: 8px; background: var(--accent); }
.clock-n { font: 600 clamp(1.8rem, 6vw, 2.8rem)/1.2 var(--font-num); font-variant-numeric: tabular-nums; padding-top: 6px; }
.clock-l { font-size: 0.8rem; color: var(--muted); padding-bottom: 8px; }

/* Número a letras */
.letras-out { display: grid; gap: 14px; }
.letras-box { border: 1px solid var(--line); border-radius: 8px; padding: 14px; background: var(--field); display: grid; gap: 8px; }
.letras-box .lbl { color: var(--muted); font-size: 0.82rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.06em; }
.letras-text { font: 600 1.15rem/1.45 var(--font-body); overflow-wrap: anywhere; }
.letras-text.mono { font-family: var(--font-num); font-size: 1rem; }
.letras-box .btn { justify-self: start; }