/* =============================================================
   EstimateCalcs — identidad industrial.
   Deliberadamente distinta de los demás proyectos: pizarra + ámbar
   de señalización, titulares condensados, cifras grandes, esquinas
   rectas y retícula de plano. Debe sentirse como una herramienta de
   obra, no como una web financiera.
   ============================================================= */
:root {
  --bg: #f4f5f7;
  --bg-grid: #e8eaee;
  --surface: #ffffff;
  --ink: #1a1f26;
  --ink-soft: #59636f;
  --line: #d3d8de;
  --line-strong: #1a1f26;
  --accent: #d97706;          /* ámbar de señalización */
  --accent-strong: #b45309;
  --accent-soft: #fef3e2;
  --accent-ink: #1a1f26;
  --slate: #2f3a46;
  --ok: #15803d;
  --warn: #b45309;
  --warn-bg: #fef3e2;
  --danger: #b91c1c;
  --radius: 4px;              /* esquinas casi rectas, no redondeadas */
  --gutter: clamp(1rem, 4vw, 2.25rem);
  --sans: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
  --display: "Archivo", "Arial Narrow", var(--sans);
  --mono: "Roboto Mono", ui-monospace, "SF Mono", Consolas, monospace;
  --ease: cubic-bezier(0.2, 0, 0, 1);
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14181d;
    --bg-grid: #1b2026;
    --surface: #1c2229;
    --ink: #eef1f4;
    --ink-soft: #9aa5b1;
    --line: #2e3640;
    --line-strong: #4a5561;
    --accent: #f59e0b;
    --accent-strong: #fbbf24;
    --accent-soft: #2a2011;
    --accent-ink: #14181d;
    --slate: #c3ccd6;
    --ok: #4ade80;
    --warn: #fbbf24;
    --warn-bg: #2a2011;
    --danger: #f87171;
  }
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  font-family: var(--sans);
  font-size: 16px; line-height: 1.6;
  color: var(--ink);
  background-color: var(--bg);
  /* retícula sutil de plano de obra */
  background-image:
    linear-gradient(var(--bg-grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--bg-grid) 1px, transparent 1px);
  background-size: 28px 28px;
  -webkit-font-smoothing: antialiased;
  overflow-x: clip;
}
img, svg, canvas { 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 {
  font-family: var(--display);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: -0.01em;
  line-height: 1.08;
  text-wrap: balance;
}
::selection { background: var(--accent); color: var(--accent-ink); }

/* Accesibilidad: foco siempre visible y con área generosa (WCAG 2.4.7) */
:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 2px;
}
.skip-link {
  position: fixed; top: -100px; left: 1rem; z-index: 999;
  padding: .7rem 1.1rem; background: var(--ink); color: var(--bg);
  font-weight: 700; text-decoration: none; border-radius: var(--radius);
}
.skip-link:focus { top: 1rem; }
.visually-hidden {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

.container { max-width: 1080px; margin-inline: auto; padding-inline: var(--gutter); }

/* ---------- Cabecera: barra sólida tipo señalización ---------- */
.site-header {
  background: var(--ink);
  border-bottom: 4px solid var(--accent);
}
.site-header .container {
  display: flex; align-items: center; justify-content: space-between;
  gap: 1rem; padding-block: .8rem;
}
.logo {
  display: inline-flex; align-items: center; gap: .55rem;
  font-family: var(--display); font-weight: 700; font-size: 1.15rem;
  text-transform: uppercase; letter-spacing: .01em;
  color: #fff; text-decoration: none;
}
.logo svg { width: 26px; height: 26px; flex: none; }
.logo em { font-style: normal; color: var(--accent); }
.header-nav { display: flex; gap: .35rem; flex-wrap: wrap; }
.header-nav a {
  color: #cfd6de; text-decoration: none; font-weight: 600; font-size: .87rem;
  padding: .4rem .7rem; border-radius: var(--radius);
  transition: background .18s var(--ease), color .18s var(--ease);
}
.header-nav a:hover { background: rgba(255,255,255,.1); color: #fff; }
.header-nav .nav-primary { color: var(--accent); }

/* ---------- Hero ---------- */
.tool-hero { padding: 1.8rem 0 1.1rem; }
.tool-hero h1 { font-size: clamp(1.7rem, 5vw, 2.7rem); max-width: 20ch; }
.tool-hero .sub {
  margin-top: .6rem; color: var(--ink-soft);
  max-width: 60ch; font-size: 1.03rem;
}

/* ---------- Tarjeta de herramienta ---------- */
.tool-card {
  background: var(--surface);
  border: 2px solid var(--line-strong);
  border-radius: var(--radius);
  padding: clamp(1.1rem, 3vw, 1.8rem);
  box-shadow: 6px 6px 0 rgba(26,31,38,.08);
}
.tool-form { display: grid; gap: 1.05rem; }
.field { display: grid; gap: .3rem; min-width: 0; }
.field label { font-weight: 700; font-size: .84rem; text-transform: uppercase; letter-spacing: .04em; }
.field .hint { font-size: .8rem; color: var(--ink-soft); }
.field input[type="number"], .field select {
  width: 100%; padding: .66rem .75rem;
  font: inherit; font-variant-numeric: tabular-nums;
  color: var(--ink); background: var(--bg);
  border: 2px solid var(--line); border-radius: var(--radius);
  transition: border-color .18s var(--ease);
}
.field input:focus, .field select:focus { border-color: var(--accent); outline: none; }
.field input[aria-invalid="true"] { border-color: var(--danger); }
.input-unit { display: grid; grid-template-columns: 1fr auto; gap: .4rem; }
.input-unit select { width: auto; }

.btn-primary {
  display: inline-flex; align-items: center; justify-content: center; gap: .5rem;
  background: var(--accent); color: var(--accent-ink);
  font-family: var(--display); font-weight: 700; font-size: 1.02rem;
  text-transform: uppercase; letter-spacing: .03em;
  padding: .85rem 1.7rem; border-radius: var(--radius);
  border-bottom: 3px solid var(--accent-strong);
  transition: filter .18s var(--ease), transform .18s var(--ease);
}
.btn-primary:hover { filter: brightness(1.06); transform: translateY(-1px); }
.btn-primary:active { transform: translateY(1px); border-bottom-width: 1px; }
.btn-secondary {
  display: inline-flex; align-items: center; gap: .45rem;
  font-weight: 700; font-size: .86rem; text-transform: uppercase; letter-spacing: .03em;
  color: var(--ink); padding: .55rem 1rem;
  border: 2px solid var(--line-strong); border-radius: var(--radius);
  background: var(--surface); text-decoration: none;
  transition: background .18s var(--ease), color .18s var(--ease);
}
.btn-secondary:hover { background: var(--ink); color: var(--surface); }

.tool-note {
  display: flex; gap: .55rem; align-items: flex-start;
  font-size: .84rem; color: var(--ink-soft); margin-top: 1rem;
  padding-top: .9rem; border-top: 1px dashed var(--line);
}
.tool-note svg { flex: none; margin-top: .2rem; }

.tool-warning {
  margin-top: .7rem; padding: .65rem .9rem;
  border-left: 4px solid var(--warn); background: var(--warn-bg);
  color: var(--warn); font-size: .87rem; font-weight: 600;
}
.tool-warning:empty { display: none; }

/* ---------- Resultados: cifras grandes, monoespaciadas ---------- */
.results { display: none; margin-top: 1.5rem; }
.tool-card[data-state="done"] .results { display: block; }

.result-grid { display: grid; gap: .7rem; grid-template-columns: repeat(auto-fit, minmax(155px, 1fr)); }
.result-item {
  background: var(--bg); border: 2px solid var(--line);
  border-radius: var(--radius); padding: .85rem .95rem;
}
.result-item .k {
  font-size: .73rem; font-weight: 700; color: var(--ink-soft);
  text-transform: uppercase; letter-spacing: .06em;
}
.result-item .v {
  font-family: var(--mono); font-weight: 700;
  font-size: clamp(1.25rem, 3.4vw, 1.7rem);
  font-variant-numeric: tabular-nums; margin-top: .2rem;
  line-height: 1.15; word-break: break-word;
}
.result-item.highlight { background: var(--accent-soft); border-color: var(--accent); }
.result-item.highlight .v { color: var(--accent-strong); }

.result-actions { display: flex; flex-wrap: wrap; gap: .6rem; margin-top: 1.1rem; }

.breakdown { margin-top: 1.2rem; }
.breakdown h3 { font-size: .95rem; margin-bottom: .5rem; }
.breakdown table { width: 100%; border-collapse: collapse; font-size: .88rem; }
.breakdown th, .breakdown td { padding: .5rem .6rem; text-align: right; border-bottom: 1px solid var(--line); }
.breakdown th:first-child, .breakdown td:first-child { text-align: left; }
.breakdown thead th {
  font-size: .72rem; text-transform: uppercase; letter-spacing: .05em;
  color: var(--ink-soft); border-bottom: 2px solid var(--line-strong);
}
.breakdown td { font-variant-numeric: tabular-nums; }

/* ---------- Secciones de contenido ---------- */
.section { margin-top: 2.8rem; }
.section h2 { font-size: clamp(1.3rem, 3.2vw, 1.75rem); margin-bottom: .9rem; }
.section .prose { max-width: 70ch; }
.section .prose p + p { margin-top: .85rem; }
.section .prose strong { color: var(--accent-strong); }
.meta-updated { font-size: .82rem; color: var(--ink-soft); margin-bottom: 1rem; }

.steps { display: grid; gap: .9rem; margin-top: 1rem; }
.step {
  display: flex; gap: .9rem; align-items: flex-start;
  background: var(--surface); border: 2px solid var(--line);
  border-radius: var(--radius); padding: 1rem;
}
.step .n {
  flex: none; width: 30px; height: 30px;
  display: grid; place-items: center;
  background: var(--ink); color: var(--accent);
  font-family: var(--mono); font-weight: 700; font-size: .9rem;
  border-radius: var(--radius);
}
.step h3 { font-size: .93rem; margin-bottom: .2rem; }
.step p { font-size: .88rem; color: var(--ink-soft); }

.faq details {
  background: var(--surface); border: 2px solid var(--line);
  border-radius: var(--radius); padding: .9rem 1.1rem; margin-bottom: .65rem;
}
.faq summary {
  font-weight: 700; cursor: pointer; list-style: none;
  display: flex; justify-content: space-between; gap: 1rem; align-items: center;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+"; font-family: var(--mono); font-size: 1.25rem;
  color: var(--accent-strong); transition: rotate .2s var(--ease);
}
.faq details[open] summary::after { rotate: 45deg; }
.faq details p { margin-top: .6rem; color: var(--ink-soft); font-size: .93rem; }

.sources ul { list-style: none; padding: 0; display: grid; gap: .45rem; margin-top: .8rem; }
.sources a {
  display: inline-flex; align-items: center; gap: .4rem;
  font-size: .89rem; font-weight: 600; color: var(--accent-strong); text-decoration: none;
}
.sources a::before { content: "→"; font-family: var(--mono); }
.sources a:hover { text-decoration: underline; }

/* ---------- Rejilla de herramientas ---------- */
.tool-section { margin-top: 1.7rem; }
.tool-section:first-child { margin-top: .5rem; }
.tool-section h3 { font-size: 1rem; display: flex; align-items: center; gap: .5rem; }
.tool-section.is-primary h3::before {
  content: ""; width: 14px; height: 14px; background: var(--accent); flex: none;
}
.tool-section:not(.is-primary) {
  margin-top: 2.2rem; padding-top: 1.4rem; border-top: 2px solid var(--line);
}
.tool-section:not(.is-primary) h3 { color: var(--ink-soft); }
.tool-section-desc { font-size: .86rem; color: var(--ink-soft); margin-top: .25rem; }
.tools-grid { display: grid; gap: .8rem; grid-template-columns: repeat(auto-fill, minmax(215px, 1fr)); margin-top: 1rem; }
.tool-link {
  display: block; text-decoration: none;
  background: var(--surface); border: 2px solid var(--line);
  border-radius: var(--radius); padding: .95rem 1rem;
  transition: border-color .18s var(--ease), transform .18s var(--ease);
}
.tool-link:hover { border-color: var(--accent); transform: translate(-2px, -2px); box-shadow: 4px 4px 0 rgba(217,119,6,.25); }
.tool-link h4 { font-family: var(--display); font-size: .93rem; text-transform: uppercase; margin-bottom: .2rem; }
.tool-link p { font-size: .84rem; color: var(--ink-soft); }

/* ---------- Anuncios (placeholders) ---------- */
.ad-slot {
  margin-top: 2.4rem; min-height: 100px;
  display: grid; place-items: center;
  border: 2px dashed var(--line);
  border-radius: var(--radius);
  color: var(--ink-soft); font-size: .72rem;
  letter-spacing: .14em; text-transform: uppercase;
}

/* ---------- Pie ---------- */
.site-footer {
  margin-top: 4rem; padding: 2.2rem 0 2.8rem;
  background: var(--ink); color: #b6bfc9;
  border-top: 4px solid var(--accent);
  font-size: .87rem;
}
.site-footer .container { display: grid; gap: .9rem; }
.site-footer nav { display: flex; flex-wrap: wrap; gap: 1.1rem; }
.site-footer a { color: #dbe1e8; text-decoration: none; }
.site-footer a:hover { color: var(--accent); text-decoration: underline; }

/* ---------- Páginas legales ---------- */
.legal { padding-top: 1.8rem; max-width: 72ch; }
.legal h1 { font-size: clamp(1.5rem, 4vw, 2.1rem); margin-bottom: 1rem; }
.legal h2 { font-size: 1.1rem; margin: 1.7rem 0 .5rem; }
.legal p, .legal li { color: var(--ink-soft); font-size: .95rem; }
.legal ul { padding-left: 1.2rem; }

/* ---------- Responsive ---------- */
@media (min-width: 560px) {
  .tool-form { grid-template-columns: 1fr 1fr; align-items: start; }
  .tool-form .field-full, .tool-form .form-actions { grid-column: 1 / -1; }
}
@media (min-width: 760px) {
  .steps { grid-template-columns: repeat(3, 1fr); }
  .tool-form { grid-template-columns: repeat(3, 1fr); }
}

/* ---------- Impresión ---------- */
@media print {
  body { background: #fff; }
  .site-header, .site-footer, .ad-slot, .section, .tool-note,
  .result-actions, .skip-link, .tool-form { display: none !important; }
  .tool-card { border: 0; box-shadow: none; padding: 0; }
  .results { display: block !important; }
}

/* ---------- Movimiento reducido ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .btn-primary:hover, .tool-link:hover { transform: none; }
  *, *::before, *::after { transition-duration: .01ms !important; }
}

/* ---------- Contraste alto ---------- */
@media (prefers-contrast: more) {
  :root { --line: var(--ink); --ink-soft: var(--ink); }
}