/* =============================================================
   1. Tokens
   ============================================================= */
:root {
  --bg:        #faf7f0;
  --bg-2:      #f1ece1;
  --paper:     #ffffff;
  --ink:       #16140e;
  --ink-soft:  #3a342e;
  --ink-mute:  #6e6760;
  --accent:    #960018;
  --accent-soft: #b8324a;
  --line:      rgba(22,20,14,0.16);
  --line-strong: #16140e;
  --ok:        #2f5d3a;

  --serif-display: "Playfair Display", "Source Serif 4", Georgia, serif;
  --serif-body:    "Source Serif 4", Georgia, serif;
  --sans:          "Inter", -apple-system, BlinkMacSystemFont, sans-serif;
  --mono:          "JetBrains Mono", ui-monospace, monospace;

  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --radius: 2px;
  --container: 1120px;
}

/* =============================================================
   2. Reset & base
   ============================================================= */
*, *::before, *::after { box-sizing: border-box; margin: 0; }
html { -webkit-text-size-adjust: 100%; tab-size: 2; scroll-behavior: smooth; }
body {
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: clip;
  overscroll-behavior-y: none;
}
img, svg, video { display: block; max-width: 100%; }
img { height: auto; }
button { font: inherit; color: inherit; cursor: pointer; border: 0; background: none; }
a { color: inherit; text-decoration: none; }
p { text-wrap: pretty; }
h1, h2, h3, h4 { font-family: var(--serif-display); text-wrap: balance; line-height: 1.1; letter-spacing: -0.01em; font-weight: 700; }
::selection { background: var(--accent); color: var(--bg); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }
input, select { font: inherit; color: inherit; }

.skip-link {
  position: fixed; top: -100px; left: 1rem;
  padding: .6rem 1rem; background: var(--ink); color: var(--bg);
  z-index: 9999; border-radius: 8px; font-weight: 600;
}
.skip-link:focus { top: 1rem; }

/* =============================================================
   3. Utilities
   ============================================================= */
.container { max-width: var(--container); margin-inline: auto; padding-inline: 1.25rem; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; }
.hairline-top { border-top: 1px solid var(--line-strong); }
.hairline-bottom { border-bottom: 1px solid var(--line-strong); }
.kicker {
  font-family: var(--sans); font-size: 0.72rem; font-weight: 700;
  letter-spacing: 0.14em; text-transform: uppercase; color: var(--accent);
}
.mono { font-family: var(--mono); }

/* =============================================================
   4. Masthead / nav
   ============================================================= */
.masthead {
  background: var(--bg);
  position: sticky; top: 0; z-index: 50;
}
.masthead-bar {
  display: flex; align-items: center; justify-content: space-between;
  padding: 1rem 0;
}
.brand {
  font-family: var(--serif-display); font-weight: 700; font-size: 1.4rem;
  display: flex; align-items: baseline; gap: 0.35rem;
}
.brand em { color: var(--accent); font-style: normal; }
.brand-sub { font-family: var(--sans); font-size: 0.68rem; color: var(--ink-mute); letter-spacing: 0.05em; }

nav.main-nav { display: none; gap: 1.75rem; }
nav.main-nav a {
  font-size: 0.9rem; font-weight: 600; position: relative; padding-bottom: 2px;
}
nav.main-nav a::after {
  content: ""; position: absolute; left: 0; right: 100%; bottom: 0; height: 1px;
  background: var(--accent); transition: right 0.3s var(--ease-out);
}
nav.main-nav a:hover::after { right: 0; }

.nav-toggle { display: inline-flex; border: 1px solid var(--line-strong); padding: 0.5rem 0.75rem; font-size: 0.8rem; font-weight: 700; }

@media (min-width: 720px) {
  nav.main-nav { display: flex; }
  .nav-toggle { display: none; }
}

/* =============================================================
   5. Components
   ============================================================= */
.btn {
  display: inline-flex; align-items: center; gap: 0.5rem;
  padding: 0.85rem 1.5rem; font-weight: 700; font-size: 0.95rem;
  border: 1px solid var(--line-strong);
  transition: background 0.2s var(--ease-out), color 0.2s var(--ease-out);
}
.btn-primary { background: var(--ink); color: var(--bg); border-color: var(--ink); }
.btn-primary:hover { background: var(--accent); border-color: var(--accent); }
.btn-ghost:hover { background: var(--ink); color: var(--bg); }

.card {
  background: var(--paper); border: 1px solid var(--line-strong);
  padding: 1.75rem; transition: transform 0.25s var(--ease-out), box-shadow 0.25s var(--ease-out);
}
.card:hover { transform: translateY(-3px); box-shadow: 6px 6px 0 var(--accent); }
.card-num { font-family: var(--mono); color: var(--accent); font-size: 0.85rem; font-weight: 700; }

/* Tool grid */
.tools-grid {
  display: grid; gap: 1px; background: var(--line-strong);
  border: 1px solid var(--line-strong); margin-top: 2rem;
}
.tool-card {
  background: var(--paper); padding: 2rem 1.5rem; display: flex; flex-direction: column; gap: 0.75rem;
  transition: background 0.2s var(--ease-out);
}
.tool-card:hover { background: var(--bg-2); }
.tool-card h3 { font-size: 1.25rem; }
.tool-card p { color: var(--ink-mute); font-size: 0.92rem; }
.tool-card .go { margin-top: auto; font-family: var(--mono); font-size: 0.82rem; font-weight: 700; color: var(--accent); }
@media (min-width: 720px) { .tools-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1024px) { .tools-grid { grid-template-columns: repeat(3, 1fr); } }

/* Forms */
.field { display: flex; flex-direction: column; gap: 0.4rem; margin-bottom: 1.25rem; }
.field label { font-weight: 700; font-size: 0.88rem; }
.field .hint { font-size: 0.78rem; color: var(--ink-mute); }
.field input[type="number"],
.field input[type="text"],
.field select {
  padding: 0.75rem 0.9rem; border: 1px solid var(--line-strong); background: var(--paper);
  font-family: var(--mono); font-size: 1rem;
}
.field-row { display: grid; gap: 1rem; }
@media (min-width: 640px) { .field-row.two { grid-template-columns: 1fr 1fr; } }

.radio-group { display: flex; flex-wrap: wrap; gap: 0.6rem; }
.radio-chip {
  border: 1px solid var(--line-strong); padding: 0.55rem 1rem; font-size: 0.85rem; font-weight: 600;
  cursor: pointer; transition: background 0.15s, color 0.15s;
}
.radio-chip input { position: absolute; opacity: 0; pointer-events: none; }
.radio-chip.is-active { background: var(--ink); color: var(--bg); }

/* Result panel */
.result-panel {
  background: var(--ink); color: var(--bg);
  padding: 2rem; margin-top: 1.5rem; position: relative;
}
.result-panel .kicker { color: var(--accent-soft); }
.result-big {
  font-family: var(--mono); font-size: clamp(2rem, 6vw, 3.2rem); font-weight: 700; line-height: 1;
  margin-block: 0.5rem;
}
.result-rows { display: grid; gap: 0.5rem; margin-top: 1.25rem; border-top: 1px solid rgba(250,247,240,0.2); padding-top: 1.25rem; }
.result-row { display: flex; justify-content: space-between; font-size: 0.92rem; }
.result-row span:last-child { font-family: var(--mono); }
.disclaimer {
  font-size: 0.8rem; color: var(--ink-mute); margin-top: 1rem; border-left: 3px solid var(--accent);
  padding: 0.6rem 0.9rem; background: var(--bg-2);
}

/* Table (tramos autónomos) */
.tramos-table { width: 100%; border-collapse: collapse; font-size: 0.88rem; margin-top: 1.5rem; }
.tramos-table th, .tramos-table td { border: 1px solid var(--line); padding: 0.6rem 0.75rem; text-align: left; }
.tramos-table th { background: var(--ink); color: var(--bg); font-weight: 700; }
.tramos-table td.mono { font-family: var(--mono); }
.tramos-table tr.is-current td { background: rgba(150,0,24,0.08); font-weight: 700; }

/* FAQ */
.faq-item { border-bottom: 1px solid var(--line); }
.faq-q {
  width: 100%; text-align: left; padding: 1.25rem 0; display: flex; justify-content: space-between;
  align-items: center; font-weight: 700; font-size: 1.02rem;
}
.faq-q .plus { font-family: var(--mono); font-size: 1.2rem; transition: transform 0.2s var(--ease-out); }
.faq-item.is-open .faq-q .plus { transform: rotate(45deg); }
.faq-a { max-height: 0; overflow: hidden; transition: max-height 0.3s var(--ease-out); color: var(--ink-mute); }
.faq-item.is-open .faq-a { max-height: 300px; }
.faq-a p { padding-bottom: 1.25rem; }

/* =============================================================
   6. Sections
   ============================================================= */
.hero { padding: 3rem 0 2.5rem; }
.hero .kicker { display: block; margin-bottom: 0.9rem; }
.hero h1 { font-size: clamp(2rem, 5.5vw, 3.4rem); max-width: 16ch; }
.hero h1 em { color: var(--accent); font-style: italic; }
.hero p.lede { max-width: 56ch; font-size: 1.1rem; color: var(--ink-soft); margin-top: 1.1rem; font-family: var(--serif-body); }
.hero .hero-actions { margin-top: 1.75rem; display: flex; gap: 0.75rem; flex-wrap: wrap; }

.page-hero { padding: 2.5rem 0 1.5rem; }
.page-hero h1 { font-size: clamp(1.7rem, 4.5vw, 2.6rem); }
.page-hero p.lede { max-width: 62ch; color: var(--ink-soft); margin-top: 0.85rem; font-family: var(--serif-body); font-size: 1.05rem; }

.calc-layout { display: grid; gap: 2rem; padding-block: 1rem 3rem; }
@media (min-width: 960px) { .calc-layout { grid-template-columns: 1fr 1fr; align-items: start; } }

.about-strip { background: var(--bg-2); padding: 2.5rem 0; margin-top: 2rem; }
.about-strip .grid { display: grid; gap: 1.5rem; }
@media (min-width: 720px) { .about-strip .grid { grid-template-columns: 2fr 1fr; align-items: center; } }

.faq-section { padding: 3rem 0; }
.faq-section h2 { font-size: 1.8rem; margin-bottom: 1rem; }

footer.site-footer { padding: 2.5rem 0; margin-top: 2rem; }
.footer-grid { display: grid; gap: 1.5rem; }
@media (min-width: 720px) { .footer-grid { grid-template-columns: 2fr 1fr 1fr; } }
.footer-grid h4 { font-family: var(--sans); font-size: 0.85rem; font-weight: 700; margin-bottom: 0.6rem; }
.footer-grid ul { list-style: none; display: flex; flex-direction: column; gap: 0.4rem; font-size: 0.9rem; color: var(--ink-mute); }
.footer-grid a:hover { color: var(--accent); }
.footer-bottom { margin-top: 2rem; padding-top: 1.25rem; border-top: 1px solid var(--line); font-size: 0.8rem; color: var(--ink-mute); display: flex; flex-wrap: wrap; gap: 0.75rem 1.5rem; justify-content: space-between; }

/* Legal pages */
.legal-content { max-width: 72ch; padding-block: 2.5rem 4rem; }
.legal-content h2 { font-size: 1.35rem; margin-top: 2rem; margin-bottom: 0.6rem; }
.legal-content p, .legal-content li { color: var(--ink-soft); margin-bottom: 0.9rem; }
.legal-content ul { padding-left: 1.25rem; }

/* =============================================================
   7. Effects
   ============================================================= */
[data-reveal] { opacity: 0; transform: translateY(14px); transition: opacity 0.6s var(--ease-out), transform 0.6s var(--ease-out); }
[data-reveal].is-visible { opacity: 1; transform: none; }
.is-ready .card, .is-ready .tool-card { will-change: transform; }

/* =============================================================
   8. Responsive handled inline above (mobile-first)
   ============================================================= */

/* =============================================================
   9. Reduced motion — only intrusive effects
   ============================================================= */
@media (prefers-reduced-motion: reduce) {
  [data-reveal] { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}