:root {
  --bg: #f7f8fa;
  --surface: #ffffff;
  --text: #1c2430;
  --muted: #5b6676;
  --border: #dde2e8;
  --primary: #0b6e4f;
  --primary-dark: #08523b;
  --accent-bg: #e8f4ef;
  --warn-bg: #fff8e6;
  --warn-border: #e0a800;
  --error: #b42318;
  --radius: 10px;
  --max: 960px;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  font-size: 17px;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
}

a { color: var(--primary); }
a:hover { color: var(--primary-dark); }

.container { max-width: var(--max); margin: 0 auto; padding: 0 16px; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }

/* Header */
.site-header { background: var(--surface); border-bottom: 1px solid var(--border); }
.site-header .container { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 8px 24px; padding-top: 12px; padding-bottom: 12px; }
.logo { font-weight: 800; font-size: 1.3rem; color: var(--text); text-decoration: none; letter-spacing: -0.01em; }
.logo span { color: var(--primary); }
.nav { display: flex; flex-wrap: wrap; gap: 4px 18px; font-size: 0.95rem; }
.nav a { color: var(--muted); text-decoration: none; }
.nav a:hover, .nav a[aria-current="page"] { color: var(--primary); }
.nav a.active { color: var(--primary); font-weight: 600; }

/* Content */
main { padding: 24px 0 48px; }
h1 { font-size: 2rem; line-height: 1.25; margin: 8px 0 12px; letter-spacing: -0.01em; }
h2 { font-size: 1.4rem; line-height: 1.3; margin-top: 2em; }
h3 { font-size: 1.1rem; margin-top: 1.5em; }
.lead { font-size: 1.12rem; color: var(--muted); max-width: 46em; }
.breadcrumb { font-size: 0.85rem; color: var(--muted); }
.breadcrumb a { color: var(--muted); }
.formula { background: var(--surface); border: 1px solid var(--border); border-radius: 8px; padding: 10px 14px; font-family: ui-monospace, Consolas, monospace; font-size: 0.95rem; overflow-x: auto; }
.updated { font-size: 0.85rem; color: var(--muted); }

/* Calculator */
.calc {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  margin: 20px 0;
}
.calc-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 16px; }
.field label { display: block; font-weight: 600; font-size: 0.92rem; margin-bottom: 4px; }
.field input, .field select {
  width: 100%;
  padding: 10px 12px;
  font: inherit;
  font-size: 1rem;
  font-weight: 400;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: #fff;
  color: var(--text);
}
.field label > input { margin-top: 4px; }
.field input:focus, .field select:focus { outline: 2px solid var(--primary); outline-offset: 1px; }
.field small { display: block; color: var(--muted); font-size: 0.8rem; margin-top: 2px; }

.results {
  margin-top: 20px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 12px;
}
.result { background: var(--accent-bg); border-radius: 8px; padding: 12px 14px; }
.result .label { font-size: 0.85rem; color: var(--muted); }
.result .value { font-size: 1.35rem; font-weight: 700; color: var(--primary-dark); font-variant-numeric: tabular-nums; }
.result.main .value { font-size: 1.75rem; }

.result.neutral { background: var(--bg); }
.result.neutral .value { color: var(--text); }
.result.warn { background: var(--warn-bg); }

/* Form sections, checkboxes and collapsible advanced options */
.calc-subhead { font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.05em; color: var(--muted); font-weight: 700; margin: 24px 0 10px; }
.calc-subhead:first-child { margin-top: 0; }
.check { display: flex; align-items: center; gap: 10px; font-size: 0.92rem; font-weight: 600; min-height: 44px; cursor: pointer; }
.check input { width: 18px; height: 18px; margin: 0; accent-color: var(--primary); flex: none; }
details.advanced { margin-top: 18px; border-top: 1px solid var(--border); padding-top: 14px; }
details.advanced > summary { cursor: pointer; font-weight: 600; color: var(--primary); margin-bottom: 14px; }

.calc-message { margin: 16px 0 0; font-size: 0.95rem; }
.calc-message:empty { display: none; }
.calc-message.error { color: var(--error); font-weight: 600; }

.breakdown { margin-top: 16px; }
.breakdown table td:last-child { font-weight: 600; }
.breakdown tr:last-child > * { background: var(--bg); font-weight: 700; }

.table-wrap { overflow-x: auto; margin-top: 12px; }
table { width: 100%; border-collapse: collapse; font-size: 0.92rem; font-variant-numeric: tabular-nums; }
th, td { padding: 8px 10px; border-bottom: 1px solid var(--border); text-align: right; white-space: nowrap; }
th:first-child, td:first-child { text-align: left; }
th { background: var(--bg); font-weight: 600; }

details.schedule { margin-top: 16px; }
details.schedule summary { cursor: pointer; font-weight: 600; color: var(--primary); }

/* Buttons */
.btn {
  display: inline-block;
  font: inherit;
  font-size: 0.95rem;
  font-weight: 600;
  padding: 9px 16px;
  border-radius: 8px;
  border: 1px solid var(--primary);
  background: var(--surface);
  color: var(--primary);
  cursor: pointer;
}
.btn:hover { background: var(--accent-bg); }
.btn-link { background: none; border: none; color: var(--muted); cursor: pointer; font: inherit; font-size: 0.85rem; text-decoration: underline; padding: 4px; }
.btn-link:hover { color: var(--error); }

/* Debt payoff: one row per debt */
.debt-list { display: grid; gap: 12px; margin-bottom: 16px; }
.debt-row {
  display: grid;
  grid-template-columns: 1.5fr 1fr 0.8fr 1fr auto;
  gap: 10px;
  align-items: end;
  padding-bottom: 12px;
  border-bottom: 1px dashed var(--border);
}
.debt-actions { display: flex; flex-wrap: wrap; gap: 12px; align-items: end; justify-content: space-between; }
.debt-actions .field { min-width: 220px; }

.compare { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 16px; margin-top: 20px; }
.compare-col { border: 1px solid var(--border); border-radius: var(--radius); padding: 16px; }
.compare-col h3 { margin: 0; }
.compare-col .muted { color: var(--muted); font-size: 0.85rem; margin: 0 0 10px; }
.compare-col dl { margin: 0; display: grid; grid-template-columns: auto 1fr; gap: 4px 12px; }
.compare-col dt { color: var(--muted); font-size: 0.9rem; }
.compare-col dd { margin: 0; font-weight: 700; text-align: right; font-variant-numeric: tabular-nums; }
.compare-col ol { margin: 12px 0 0; padding-left: 1.2em; font-size: 0.92rem; }
.compare-col.best { border-color: var(--primary); box-shadow: inset 0 0 0 1px var(--primary); }
.badge { display: inline-block; font-size: 0.72rem; font-weight: 700; letter-spacing: 0.02em; color: #fff; background: var(--primary); border-radius: 999px; padding: 2px 9px; margin-left: 6px; vertical-align: middle; }
.verdict { margin-top: 16px; background: var(--accent-bg); border-radius: 8px; padding: 12px 14px; }
.verdict:empty { display: none; }

/* Article helpers */
.summary-box { background: var(--accent-bg); border-radius: var(--radius); padding: 14px 20px; margin: 20px 0; }
.summary-box h2 { font-size: 1.05rem; margin: 4px 0 6px; }
.summary-box ul { margin: 0; padding-left: 1.2em; }
.toc { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 12px 20px; margin: 20px 0; }
.toc h2 { font-size: 1rem; margin: 4px 0 6px; }
.toc ol { margin: 0; padding-left: 1.2em; font-size: 0.95rem; }

/* Home page: calculator finder */
.finder { margin: 20px 0 4px; }
.finder label { display: block; font-weight: 600; font-size: 0.92rem; margin-bottom: 4px; }
.finder input { width: 100%; max-width: 520px; padding: 12px 14px; font: inherit; border: 1px solid var(--border); border-radius: 8px; background: var(--surface); color: var(--text); }
.finder input:focus { outline: 2px solid var(--primary); outline-offset: 1px; }
.group-title { margin-bottom: 0; }
.group-title a { color: inherit; text-decoration: none; }
.group-title a:hover { color: var(--primary); }
.empty-state { color: var(--muted); }

/* Home page cards */
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 16px; margin: 24px 0; }
.card {
  display: block;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  text-decoration: none;
  color: var(--text);
  transition: border-color .15s, transform .15s;
}
.card:hover { border-color: var(--primary); transform: translateY(-2px); color: var(--text); }
.card h2, .card h3 { font-size: 1.15rem; margin: 0 0 6px; color: var(--primary); }
.card p { margin: 0; color: var(--muted); font-size: 0.95rem; }

.note {
  background: var(--warn-bg);
  border-left: 4px solid var(--warn-border);
  padding: 10px 14px;
  border-radius: 6px;
  font-size: 0.92rem;
}

.faq h3 { margin-bottom: 4px; }
.faq p { margin-top: 4px; }

.related { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 4px 20px 12px; margin-top: 32px; }

/* Footer */
.site-footer { background: var(--surface); border-top: 1px solid var(--border); padding: 24px 0; font-size: 0.88rem; color: var(--muted); }
.site-footer nav { display: flex; flex-wrap: wrap; gap: 6px 16px; margin-bottom: 8px; }
.site-footer a { color: var(--muted); }

@media (max-width: 700px) {
  .debt-row { grid-template-columns: 1fr 1fr; }
  .debt-row .field:first-child { grid-column: 1 / -1; }
}

@media (max-width: 600px) {
  h1 { font-size: 1.6rem; }
  body { font-size: 16px; }
  .calc { padding: 16px; }
}