/* ==========================================================
   CalcPrime — precision-instrument aesthetic
   Paper + ink + signal orange. Fraunces / IBM Plex.
   ========================================================== */

:root {
  --paper: #faf6ee;
  --paper-deep: #f3ecdd;
  --ink: #1b2432;
  --ink-soft: #4a5468;
  --line: #d8cfba;
  --accent: #e8571c;
  --accent-dark: #c74510;
  --accent-soft: #fdeadf;
  --good: #1e7a4f;
  --card: #fffdf8;
  --radius: 14px;
  --shadow: 0 1px 2px rgba(27, 36, 50, 0.06), 0 12px 32px -12px rgba(27, 36, 50, 0.18);
  --font-display: "Fraunces", Georgia, serif;
  --font-body: "IBM Plex Sans", -apple-system, "Segoe UI", sans-serif;
  --font-mono: "IBM Plex Mono", "SF Mono", Menlo, monospace;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-body);
  color: var(--ink);
  background-color: var(--paper);
  background-image:
    linear-gradient(rgba(27, 36, 50, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(27, 36, 50, 0.035) 1px, transparent 1px);
  background-size: 32px 32px;
  line-height: 1.65;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
}

img, svg { display: block; max-width: 100%; }

.wrap { max-width: 1080px; margin: 0 auto; padding: 0 24px; }

/* ---------- Header ---------- */
.site-header {
  border-bottom: 2px solid var(--ink);
  background: var(--paper);
  position: sticky;
  top: 0;
  z-index: 50;
}

.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 64px;
}

.brand {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.45rem;
  letter-spacing: -0.02em;
  color: var(--ink);
  text-decoration: none;
  display: flex;
  align-items: center;
}

.brand .brand-mark {
  margin-right: 10px;
  width: 30px;
  height: 30px;
  background: var(--ink);
  color: var(--paper);
  border-radius: 8px;
  display: grid;
  place-items: center;
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 600;
}

.brand em { color: var(--accent); font-style: normal; }

.site-nav { display: flex; gap: 4px; flex-wrap: wrap; }

.site-nav a {
  color: var(--ink-soft);
  text-decoration: none;
  font-size: 0.92rem;
  font-weight: 500;
  padding: 8px 12px;
  border-radius: 8px;
  transition: color 0.15s, background 0.15s;
}

.site-nav a:hover, .site-nav a[aria-current="page"] {
  color: var(--ink);
  background: var(--paper-deep);
}

@media (max-width: 760px) {
  .site-header { position: static; }
  .site-header .wrap {
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
    padding-top: 12px;
    padding-bottom: 10px;
  }
  .site-nav {
    width: 100%;
    flex-wrap: nowrap;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }
  .site-nav::-webkit-scrollbar { display: none; }
  .site-nav a { white-space: nowrap; font-size: 0.85rem; padding: 6px 10px; }
  .hero { padding: 44px 0 32px; }
  
}

/* ---------- Hero (homepage) ---------- */
.hero { padding: 72px 0 48px; position: relative; overflow: hidden; }

.hero .kicker {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 18px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.hero .kicker::before { content: ""; width: 34px; height: 2px; background: var(--accent); }

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 5.5vw, 4rem);
  line-height: 1.06;
  letter-spacing: -0.025em;
  font-weight: 600;
  max-width: 16ch;
}

.hero h1 em {
  font-style: italic;
  color: var(--accent);
}

.hero p {
  margin-top: 20px;
  max-width: 54ch;
  color: var(--ink-soft);
  font-size: 1.08rem;
}

/* ---------- Calculator index grid ---------- */
.calc-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 18px;
  padding: 24px 0 64px;
}

.calc-card {
  background: var(--card);
  border: 1.5px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 24px 22px;
  text-decoration: none;
  color: var(--ink);
  position: relative;
  overflow: hidden;
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
}

.calc-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
  border-color: var(--ink);
}

.calc-card .num {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent);
  letter-spacing: 0.12em;
}

.calc-card h2, .calc-card h3 {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  margin: 8px 0 8px;
}

.calc-card p { color: var(--ink-soft); font-size: 0.92rem; line-height: 1.55; }

.calc-card .go {
  margin-top: 16px;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.calc-card:hover .go { text-decoration: underline; }

/* ---------- Guides ---------- */
.guide-section {
  border-top: 2px solid var(--ink);
  padding: 42px 0 60px;
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 28px;
  margin-bottom: 22px;
}

.section-heading .kicker { margin-bottom: 10px; }
.section-heading h2 {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 3.5vw, 2.55rem);
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.02em;
  max-width: 22ch;
}
.section-heading > p { color: var(--ink-soft); font-size: 0.94rem; max-width: 32ch; margin-bottom: 3px; }

.guide-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; }
.guide-card, .guide-callout {
  background: var(--ink);
  color: var(--paper);
  text-decoration: none;
  border-radius: var(--radius);
  padding: 26px 24px;
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}
.guide-card { display: block; min-height: 224px; }
.guide-card:hover, .guide-callout:hover { transform: translateY(-3px); box-shadow: 0 12px 24px rgba(27, 36, 50, 0.2); }
.guide-card .num, .guide-callout .num { display: block; color: #ffb38a; font-family: var(--font-mono); font-size: 0.72rem; letter-spacing: 0.1em; }
.guide-card h3 { font-family: var(--font-display); font-size: 1.45rem; line-height: 1.2; font-weight: 600; margin: 12px 0 10px; }
.guide-card p { color: #d7dce5; font-size: 0.92rem; line-height: 1.55; }
.guide-card .go { color: #ffb38a; display: inline-block; margin-top: 18px; font-family: var(--font-mono); font-size: 0.78rem; }
.guide-callout { display: grid; gap: 8px; margin: 8px 0 28px; }
.guide-callout strong { font-family: var(--font-display); font-size: 1.3rem; line-height: 1.3; font-weight: 600; }
.guide-callout > span:last-child { color: #ffb38a; font-family: var(--font-mono); font-size: 0.78rem; }

@media (max-width: 640px) {
  .section-heading { display: block; }
  .section-heading > p { margin-top: 12px; }
  .guide-grid { grid-template-columns: 1fr; }
}

/* ---------- Page header for calculator pages ---------- */
.page-head { padding: 48px 0 8px; }

.breadcrumb {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--ink-soft);
  margin-bottom: 16px;
}

.breadcrumb a { color: var(--accent); text-decoration: none; }
.breadcrumb a:hover { text-decoration: underline; }

.page-head h1 {
  font-family: var(--font-display);
  font-size: clamp(2rem, 4.5vw, 3rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
  font-weight: 600;
}

.page-head .lede {
  margin-top: 14px;
  color: var(--ink-soft);
  max-width: 62ch;
  font-size: 1.05rem;
}

.page-head .kicker {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 12px;
}

/* ---------- Layout: calculator + rail ---------- */
.calc-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  gap: 28px;
  padding: 28px 0 56px;
  align-items: start;
}

@media (max-width: 900px) {
  .calc-layout { grid-template-columns: 1fr; }
}

/* ---------- Calculator panel ---------- */
.calc-panel {
  background: var(--card);
  border: 2px solid var(--ink);
  border-radius: var(--radius);
  box-shadow: 6px 6px 0 var(--paper-deep), 6px 6px 0 1.5px var(--line);
  overflow: hidden;
}

.calc-panel .panel-title {
  background: var(--ink);
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  padding: 12px 22px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.calc-panel .panel-title::before {
  content: "";
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--accent);
}

.calc-body { padding: 26px 22px; }

.field { margin-bottom: 18px; }

.field label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  margin-bottom: 7px;
  color: var(--ink);
}

.field .hint { font-weight: 400; color: var(--ink-soft); font-size: 0.78rem; }

.field input, .field select {
  width: 100%;
  font-family: var(--font-mono);
  font-size: 1.05rem;
  padding: 12px 14px;
  border: 1.5px solid var(--line);
  border-radius: 10px;
  background: var(--paper);
  color: var(--ink);
  transition: border-color 0.15s, box-shadow 0.15s;
}

.field input:focus, .field select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }

@media (max-width: 480px) { .field-row { grid-template-columns: 1fr; } }

.seg {
  display: inline-flex;
  border: 1.5px solid var(--ink);
  border-radius: 10px;
  overflow: hidden;
  margin-bottom: 18px;
}

.seg button {
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 600;
  padding: 9px 16px;
  border: none;
  background: transparent;
  color: var(--ink-soft);
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
}

.seg button + button { border-left: 1.5px solid var(--ink); }

.seg button.active { background: var(--ink); color: var(--paper); }

.btn-calc {
  width: 100%;
  font-family: var(--font-body);
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  padding: 15px;
  border: none;
  border-radius: 10px;
  background: var(--accent);
  color: #fff;
  cursor: pointer;
  transition: background 0.15s, transform 0.1s;
}

.btn-calc:hover { background: var(--accent-dark); }
.btn-calc:active { transform: scale(0.985); }

/* ---------- Result display ---------- */
.result {
  margin-top: 22px;
  border-top: 2px dashed var(--line);
  padding-top: 20px;
  display: none;
}

.result.show { display: block; animation: rise 0.35s ease both; }

@keyframes rise {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: none; }
}

.result .result-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

.result .result-value {
  font-family: var(--font-mono);
  font-size: clamp(1.9rem, 5vw, 2.6rem);
  font-weight: 600;
  color: var(--accent);
  letter-spacing: -0.02em;
  line-height: 1.15;
  margin-top: 4px;
  font-variant-numeric: tabular-nums;
}

.result .result-note { color: var(--ink-soft); font-size: 0.92rem; margin-top: 8px; }

.result-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-top: 16px;
}

.result-stats .stat {
  background: var(--paper);
  border: 1.5px solid var(--line);
  border-radius: 10px;
  padding: 12px 14px;
}

.result-stats .stat .s-label {
  font-size: 0.72rem;
  font-family: var(--font-mono);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--ink-soft);
}

.result-stats .stat .s-value {
  font-family: var(--font-mono);
  font-size: 1.15rem;
  font-weight: 600;
  margin-top: 2px;
  font-variant-numeric: tabular-nums;
}

/* ---------- Ad slots ---------- */

/* ---------- Affiliate offers ---------- */
.offers {
  margin-top: 26px;
  background: var(--card);
  border: 1.5px solid var(--line);
  border-left: 4px solid var(--accent);
  border-radius: var(--radius);
  padding: 22px;
}

.offers .offers-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 14px;
}

.offers h2 {
  font-family: var(--font-display);
  font-size: 1.3rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.offers .disclosure {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

.offer-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 14px 0;
  border-top: 1px dashed var(--line);
}

.offer-row:first-of-type { border-top: none; }

.offer-row .offer-info strong { display: block; font-size: 1rem; }

.offer-row .offer-info span { color: var(--ink-soft); font-size: 0.85rem; }

.offer-cta {
  flex-shrink: 0;
  font-family: var(--font-body);
  font-weight: 700;
  font-size: 0.85rem;
  color: var(--accent);
  text-decoration: none;
  border: 1.5px solid var(--accent);
  border-radius: 8px;
  padding: 9px 16px;
  white-space: nowrap;
  transition: background 0.15s, color 0.15s;
}

.offer-cta:hover { background: var(--accent); color: #fff; }

@media (max-width: 480px) {
  .offer-row { flex-direction: column; align-items: flex-start; }
}

/* ---------- Content / SEO article ---------- */
.content { max-width: 720px; padding-bottom: 24px; }

.content h2 {
  font-family: var(--font-display);
  font-size: 1.7rem;
  font-weight: 600;
  letter-spacing: -0.015em;
  margin: 44px 0 14px;
}

.content h3 {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 600;
  margin: 30px 0 10px;
}

.content p { color: var(--ink-soft); margin-bottom: 14px; }

.content ul, .content ol { color: var(--ink-soft); margin: 0 0 14px 22px; }
.content li { margin-bottom: 6px; }

.content strong { color: var(--ink); }
.content .btn-calc { display: inline-block; width: auto; text-decoration: none; margin: 2px 0 8px; }

.formula {
  background: var(--ink);
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 0.95rem;
  padding: 18px 22px;
  border-radius: 10px;
  margin: 18px 0;
  overflow-x: auto;
}

.formula .fx { color: #ffb38a; }

table.data {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
  margin: 18px 0;
  background: var(--card);
  border: 1.5px solid var(--line);
  border-radius: 10px;
  overflow: hidden;
}

table.data th {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  text-align: left;
  background: var(--paper-deep);
  padding: 10px 14px;
  border-bottom: 1.5px solid var(--line);
}

table.data td {
  padding: 9px 14px;
  border-bottom: 1px solid var(--line);
  color: var(--ink-soft);
  font-variant-numeric: tabular-nums;
}

table.data tr:last-child td { border-bottom: none; }

/* ---------- FAQ ---------- */
.faq details {
  background: var(--card);
  border: 1.5px solid var(--line);
  border-radius: 10px;
  margin-bottom: 10px;
  overflow: hidden;
}

.faq summary {
  cursor: pointer;
  font-weight: 600;
  padding: 15px 18px;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}

.faq summary::-webkit-details-marker { display: none; }

.faq summary::after {
  content: "+";
  font-family: var(--font-mono);
  color: var(--accent);
  font-size: 1.2rem;
  flex-shrink: 0;
}

.faq details[open] summary::after { content: "−"; }

.faq details p { padding: 0 18px 15px; color: var(--ink-soft); font-size: 0.95rem; }

/* ---------- Related calculators ---------- */
.related { padding: 8px 0 56px; }

.related h2 {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 18px;
}

.related .calc-grid { padding: 0; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); }

/* ---------- Footer ---------- */
.site-footer {
  border-top: 2px solid var(--ink);
  background: var(--ink);
  color: var(--paper);
  padding: 40px 0 28px;
  margin-top: 24px;
}

.site-footer .cols {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 32px;
}

@media (max-width: 720px) { .site-footer .cols { grid-template-columns: 1fr; } }

.site-footer h4 {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: #9aa5b8;
  margin-bottom: 12px;
}

.site-footer a { color: var(--paper); text-decoration: none; font-size: 0.92rem; }
.site-footer a:hover { color: var(--accent); }
.site-footer ul { list-style: none; }
.site-footer li { margin-bottom: 8px; }

.site-footer .about { color: #9aa5b8; font-size: 0.92rem; max-width: 40ch; }

.site-footer .legal {
  margin-top: 32px;
  padding-top: 18px;
  border-top: 1px solid #34405a;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: #9aa5b8;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
}

/* ---------- Utility ---------- */
.error-msg {
  color: var(--accent-dark);
  font-size: 0.85rem;
  margin-top: 10px;
  display: none;
}

.error-msg.show { display: block; }

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
  html { scroll-behavior: auto; }
}