/* =========================================================
   Ledger & Rate — design tokens
   A ledger-paper aesthetic: ruled lines, tabular mono figures,
   a brass accent for the numbers that matter, and an accounting
   double-rule under every final total.
   ========================================================= */

:root {
  --paper:        #ECE9DF;
  --paper-raised: #F6F4EC;
  --ink:          #1C2431;
  --ink-soft:     #4A5266;
  --rule:         #C9C3AF;
  --rule-strong:  #1C2431;
  --ledger-blue:  #2C4A6E;
  --brass:        #A9762F;
  --brass-soft:   #EFE3C8;
  --credit:       #3F6B4F;
  --credit-soft:  #DEE9DF;
  --debit:        #9B4038;
  --debit-soft:   #F1DFDA;

  --font-display: 'Fraunces', Georgia, serif;
  --font-body:    'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono:    'IBM Plex Mono', ui-monospace, Menlo, Consolas, monospace;

  --radius: 3px;
  --wrap: 1120px;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  line-height: 1.55;
  font-size: 16px;
}

.wrap {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 24px;
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--ink);
  color: var(--paper);
  padding: 10px 16px;
  z-index: 100;
}
.skip-link:focus { left: 16px; top: 16px; }

.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

a { color: var(--ledger-blue); }

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 600;
  color: var(--ink);
  margin: 0 0 0.4em;
  letter-spacing: -0.01em;
}

/* ---------- header ---------- */

.ledger-band {
  background: var(--ink);
  color: var(--brass-soft);
}
.ledger-band__inner {
  display: flex;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
  padding: 6px 24px;
  text-transform: uppercase;
}

.site-header {
  background: var(--paper-raised);
  border-bottom: 2px solid var(--rule-strong);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 24px;
  gap: 16px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--ink);
}
.brand__mark {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 0.95rem;
  border: 1.5px solid var(--ink);
  border-radius: 50%;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--paper);
  flex-shrink: 0;
}
.brand__text { display: flex; flex-direction: column; line-height: 1.25; }
.brand__name { font-family: var(--font-display); font-weight: 600; font-size: 1.2rem; }
.brand__tagline { font-size: 0.78rem; color: var(--ink-soft); }

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  background: none;
  border: 1.5px solid var(--ink);
  border-radius: var(--radius);
  width: 42px;
  height: 38px;
  cursor: pointer;
  padding: 0;
}
.nav-toggle span { display: block; height: 2px; width: 20px; margin: 0 auto; background: var(--ink); }

.primary-nav ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  margin: 0;
  padding: 0;
}
.primary-nav a {
  display: inline-block;
  text-decoration: none;
  color: var(--ink-soft);
  font-size: 0.88rem;
  font-weight: 500;
  padding: 8px 12px;
  border-radius: var(--radius);
  border: 1px solid transparent;
  white-space: nowrap;
}
.primary-nav a:hover { border-color: var(--rule); color: var(--ink); }
.primary-nav a.is-active {
  color: var(--ink);
  background: var(--brass-soft);
  border-color: var(--brass);
  font-weight: 600;
}

/* ---------- hero ---------- */

.hero {
  border-bottom: 1px solid var(--rule);
  background:
    repeating-linear-gradient(
      to bottom,
      transparent,
      transparent 37px,
      var(--rule) 37px,
      var(--rule) 38px
    );
}
.hero__inner { padding: 56px 24px 44px; max-width: 760px; }

.eyebrow {
  font-family: var(--font-mono);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 0.74rem;
  color: var(--brass);
  font-weight: 600;
  margin: 0 0 14px;
}

.hero h1 { font-size: clamp(2rem, 4vw, 2.75rem); }
.hero__intro { font-size: 1.08rem; color: var(--ink-soft); max-width: 60ch; }

/* ---------- calculator layout ---------- */

.calculator {
  padding: 12px 24px 64px;
}
.calculator__grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 0;
  background: var(--paper-raised);
  border: 1.5px solid var(--rule-strong);
  border-radius: var(--radius);
  overflow: hidden;
}

.calc-form {
  padding: 32px;
  border-right: 1.5px dashed var(--rule);
}
.calc-form h2 {
  font-size: 1.05rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-family: var(--font-mono);
  color: var(--ink-soft);
  margin-bottom: 20px;
}

.field {
  margin-bottom: 18px;
}
.field label {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 6px;
}
.field label .hint {
  font-weight: 400;
  color: var(--ink-soft);
  font-size: 0.78rem;
  font-family: var(--font-mono);
}
.field .input-prefix-wrap {
  position: relative;
  display: flex;
  align-items: center;
}
.field .prefix,
.field .suffix {
  position: absolute;
  font-family: var(--font-mono);
  color: var(--ink-soft);
  font-size: 0.95rem;
  pointer-events: none;
}
.field .prefix { left: 14px; }
.field .suffix { right: 14px; }

.field input[type="number"],
.field input[type="text"],
.field select {
  width: 100%;
  font-family: var(--font-mono);
  font-size: 1rem;
  padding: 11px 14px;
  border: 1.5px solid var(--rule-strong);
  border-radius: var(--radius);
  background: #fff;
  color: var(--ink);
}
.field input[data-prefix] { padding-left: 28px; }
.field input[data-suffix] { padding-right: 34px; }
.field input:focus,
.field select:focus {
  outline: 3px solid var(--brass-soft);
  outline-offset: 0;
  border-color: var(--brass);
}

.field-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.calc-note {
  font-size: 0.82rem;
  color: var(--ink-soft);
  border-top: 1px dashed var(--rule);
  padding-top: 14px;
  margin-top: 4px;
}

/* results panel */

.calc-results {
  padding: 32px;
  background: var(--paper);
}
.calc-results h2 {
  font-size: 1.05rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-family: var(--font-mono);
  color: var(--ink-soft);
  margin-bottom: 20px;
}

.ledger-line {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 10px 0;
  border-bottom: 1px solid var(--rule);
  font-size: 0.95rem;
}
.ledger-line__label { color: var(--ink-soft); }
.ledger-line__value {
  font-family: var(--font-mono);
  font-weight: 500;
  font-variant-numeric: tabular-nums;
}
.ledger-line__value.is-credit { color: var(--credit); }
.ledger-line__value.is-debit { color: var(--debit); }

.ledger-total {
  margin-top: 18px;
  padding-top: 16px;
  border-top: 2px solid var(--rule-strong);
  display: flex;
  justify-content: space-between;
  align-items: baseline;
}
.ledger-total__label {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
}
.ledger-total__value {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 1.7rem;
  color: var(--ink);
  border-bottom: 3px double var(--rule-strong);
  padding-bottom: 4px;
  font-variant-numeric: tabular-nums;
}

.ledger-callout {
  margin-top: 22px;
  background: var(--credit-soft);
  border: 1px solid var(--credit);
  border-radius: var(--radius);
  padding: 14px 16px;
  font-size: 0.9rem;
  color: #234233;
}
.ledger-callout.is-warning {
  background: var(--debit-soft);
  border-color: var(--debit);
  color: #5a231d;
}

/* ---------- explainer / content blocks ---------- */

.explainer {
  padding: 8px 24px 64px;
}
.explainer .wrap {
  max-width: 780px;
}
.explainer h2 {
  font-size: 1.5rem;
  margin-top: 2.2em;
}
.explainer h2:first-child { margin-top: 0; }
.explainer p { color: var(--ink-soft); }
.explainer ul { color: var(--ink-soft); padding-left: 1.2em; }
.explainer li { margin-bottom: 0.4em; }

.faq {
  border-top: 1px solid var(--rule);
  padding-top: 8px;
}
.faq-item {
  border-bottom: 1px solid var(--rule);
  padding: 18px 0;
}
.faq-item h3 { font-size: 1.05rem; margin-bottom: 8px; }
.faq-item p { margin: 0; }

/* ---------- site index (footer directory) ---------- */

.site-index {
  background: var(--paper-raised);
  border-top: 2px solid var(--rule-strong);
  padding: 48px 24px;
}
.site-index h2 {
  font-size: 1.3rem;
  margin-bottom: 24px;
}
.site-index__grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--rule);
  border: 1px solid var(--rule);
}
.site-index__grid li { background: var(--paper-raised); }
.site-index__grid li.is-current { background: var(--brass-soft); }
.site-index__grid a {
  display: block;
  text-decoration: none;
  color: var(--ink);
  padding: 20px;
  height: 100%;
}
.site-index__category {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--brass);
  margin-bottom: 6px;
}
.site-index__label {
  display: block;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
  margin-bottom: 6px;
}
.site-index__short {
  display: block;
  font-size: 0.85rem;
  color: var(--ink-soft);
}

/* ---------- footer ---------- */

.site-footer {
  background: var(--ink);
  color: #C7CAD4;
  padding: 40px 24px;
}
.site-footer__inner { display: flex; flex-direction: column; gap: 16px; }
.site-footer__brand { display: flex; align-items: center; gap: 12px; }
.site-footer__brand .brand__mark { border-color: #C7CAD4; color: #C7CAD4; background: transparent; }
.site-footer__brand p { margin: 0; font-family: var(--font-display); color: #fff; }
.site-footer__disclaimer { font-size: 0.82rem; max-width: 70ch; color: #9AA0B2; }
.site-footer__copy { font-size: 0.78rem; color: #767C90; margin: 0; }

/* ---------- responsive ---------- */

@media (max-width: 880px) {
  .calc-form { border-right: none; border-bottom: 1.5px dashed var(--rule); }
  .calculator__grid { grid-template-columns: 1fr; }
  .site-index__grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 720px) {
  .ledger-band__inner { flex-direction: column; gap: 2px; }
  .nav-toggle { display: flex; }
  .primary-nav {
    display: none;
    width: 100%;
    order: 3;
    padding-top: 12px;
  }
  .primary-nav.is-open { display: block; }
  .primary-nav ul { flex-direction: column; }
  .site-header__inner { flex-wrap: wrap; }
  .field-row { grid-template-columns: 1fr; }
  .site-index__grid { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  * { scroll-behavior: auto !important; }
}