/* ==========================================================================
   Mortgage Extra Payment — Design System
   ========================================================================== */

:root {
  /* Brand palette — trustworthy finance navy + savings green */
  --color-navy-950: #0a1f38;
  --color-navy-900: #0d2b4e;
  --color-navy-800: #123a66;
  --color-navy-700: #1a4d84;
  --color-navy-100: #e8f0fa;
  --color-navy-50:  #f4f8fc;

  --color-green-700: #0a7d4b;
  --color-green-600: #0e9f61;
  --color-green-500: #16b374;
  --color-green-100: #e2f7ec;

  --color-amber-600: #b5750a;
  --color-amber-100: #fdf1de;

  --color-red-600: #c23636;
  --color-red-100: #fbe9e9;

  --color-ink-900: #16202c;
  --color-ink-700: #3d4a58;
  --color-ink-500: #66748a;
  --color-ink-300: #a3b1c2;
  --color-ink-100: #dde5ee;
  --color-ink-50:  #f5f8fb;
  --color-white:   #ffffff;

  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, monospace;

  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 18px;

  --shadow-sm: 0 1px 2px rgba(10, 31, 56, 0.06), 0 1px 3px rgba(10, 31, 56, 0.08);
  --shadow-md: 0 4px 12px rgba(10, 31, 56, 0.08), 0 2px 4px rgba(10, 31, 56, 0.06);
  --shadow-lg: 0 12px 32px rgba(10, 31, 56, 0.14);

  --max-width: 1180px;
}

* , *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--color-ink-900);
  background: var(--color-white);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

a { color: var(--color-navy-700); text-decoration: none; }
a:hover { text-decoration: underline; }

h1, h2, h3, h4 { font-weight: 700; line-height: 1.25; margin: 0 0 0.5em; color: var(--color-navy-950); }
h1 { font-size: clamp(1.9rem, 1.5rem + 1.8vw, 2.75rem); }
h2 { font-size: clamp(1.5rem, 1.3rem + 0.9vw, 2rem); }
h3 { font-size: 1.25rem; }
p { margin: 0 0 1em; color: var(--color-ink-700); }

.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.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;
}

.skip-link {
  position: absolute; left: -999px; top: 0; background: var(--color-navy-900);
  color: #fff; padding: 0.75rem 1.25rem; z-index: 200; border-radius: 0 0 8px 0;
}
.skip-link:focus { left: 0; }

/* ---------------------------------- Header --------------------------------- */

.site-header {
  background: var(--color-white);
  border-bottom: 1px solid var(--color-ink-100);
  position: sticky;
  top: 0;
  z-index: 100;
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 0.85rem;
  padding-bottom: 0.85rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-weight: 800;
  font-size: 1.15rem;
  color: var(--color-navy-950);
}
.brand:hover { text-decoration: none; }
.brand .brand-mark {
  width: 36px; height: 36px; border-radius: 9px;
  background: linear-gradient(135deg, var(--color-navy-800), var(--color-green-600));
  display: flex; align-items: center; justify-content: center; color: #fff; flex-shrink: 0;
}

.main-nav ul {
  list-style: none; display: flex; gap: 1.6rem; margin: 0; padding: 0;
}
.main-nav a {
  color: var(--color-ink-700); font-weight: 600; font-size: 0.95rem;
}
.main-nav a:hover, .main-nav a.active { color: var(--color-navy-900); text-decoration: none; }

.nav-toggle {
  display: none;
  background: none; border: 1px solid var(--color-ink-100); border-radius: var(--radius-sm);
  padding: 0.4rem 0.6rem; cursor: pointer;
}

@media (max-width: 820px) {
  .main-nav { display: none; }
  .main-nav.open {
    display: block; position: absolute; top: 100%; left: 0; right: 0;
    background: #fff; border-bottom: 1px solid var(--color-ink-100); box-shadow: var(--shadow-md);
  }
  .main-nav.open ul { flex-direction: column; gap: 0; padding: 0.5rem 1.25rem 1rem; }
  .main-nav.open li { border-top: 1px solid var(--color-ink-50); }
  .main-nav.open a { display: block; padding: 0.75rem 0; }
  .nav-toggle { display: inline-flex; }
}

/* ---------------------------------- Hero ----------------------------------- */

.hero {
  background: radial-gradient(ellipse at top left, var(--color-navy-800) 0%, var(--color-navy-950) 60%);
  color: #fff;
  padding: 2.75rem 0 2.25rem;
}
.hero h1 { color: #fff; max-width: 46ch; }
.hero p.lede { color: var(--color-navy-100); max-width: 62ch; font-size: 1.05rem; }
.hero .trust-row {
  display: flex; flex-wrap: wrap; gap: 0.5rem 1.5rem; margin-top: 1.25rem;
  font-size: 0.85rem; color: var(--color-navy-100);
}
.hero .trust-row span { display: inline-flex; align-items: center; gap: 0.4rem; }

/* ------------------------------- Calculator card ---------------------------- */

.calc-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.5rem;
  margin-top: -1.75rem;
  position: relative;
  z-index: 5;
}

@media (min-width: 980px) {
  .calc-shell { grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr); align-items: start; }
}

.card {
  background: #fff;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--color-ink-100);
  padding: 1.6rem;
}

.calc-form fieldset {
  border: 0; margin: 0 0 1.35rem; padding: 0;
}
.calc-form legend {
  font-weight: 700; font-size: 0.95rem; color: var(--color-navy-900);
  padding: 0 0 0.6rem; display: flex; align-items: center; gap: 0.5rem;
}

.field-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 0.9rem;
}

.field { display: flex; flex-direction: column; gap: 0.35rem; }
.field label { font-size: 0.82rem; font-weight: 600; color: var(--color-ink-700); }
.field .hint { font-size: 0.75rem; color: var(--color-ink-500); }

input[type="text"], input[type="email"], input[type="number"], select, textarea {
  font: inherit;
  padding: 0.62rem 0.75rem;
  border-radius: var(--radius-sm);
  border: 1.5px solid var(--color-ink-100);
  background: var(--color-ink-50);
  color: var(--color-ink-900);
  width: 100%;
  transition: border-color 0.15s ease, background 0.15s ease;
}
input[type="text"]:focus, input[type="email"]:focus, input[type="number"]:focus, select:focus, textarea:focus {
  outline: none; border-color: var(--color-navy-700); background: #fff;
  box-shadow: 0 0 0 3px var(--color-navy-100);
}
textarea { resize: vertical; min-height: 140px; }

.form-status { padding: 0.75rem 0.9rem; border-radius: var(--radius-sm); font-size: 0.9rem; margin-top: 1rem; display: none; }
.form-status.success { display: block; background: var(--color-green-100); color: var(--color-green-700); border: 1px solid #bfe9d3; }
.form-status.error { display: block; background: var(--color-red-100); color: var(--color-red-600); border: 1px solid #f3c6c6; }

.input-prefix {
  position: relative;
}
.input-prefix span {
  position: absolute; left: 0.75rem; top: 50%; transform: translateY(-50%);
  color: var(--color-ink-500); font-weight: 600; pointer-events: none;
}
.input-prefix input { padding-left: 1.9rem; }

.segmented {
  display: inline-flex; background: var(--color-ink-50); border: 1px solid var(--color-ink-100);
  border-radius: var(--radius-sm); padding: 3px; gap: 3px; flex-wrap: wrap;
}
.segmented button {
  border: 0; background: transparent; padding: 0.5rem 0.9rem; border-radius: 5px;
  font: inherit; font-weight: 600; font-size: 0.85rem; color: var(--color-ink-700); cursor: pointer;
}
.segmented button[aria-pressed="true"] {
  background: var(--color-navy-900); color: #fff;
}

.radio-cards {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); gap: 0.6rem;
}
.radio-card {
  border: 1.5px solid var(--color-ink-100); border-radius: var(--radius-sm);
  padding: 0.65rem 0.8rem; cursor: pointer; background: var(--color-ink-50);
  display: flex; align-items: flex-start; gap: 0.5rem; font-size: 0.85rem;
}
.radio-card input { margin-top: 0.2rem; }
.radio-card strong { display: block; font-size: 0.85rem; color: var(--color-navy-950); }
.radio-card small { color: var(--color-ink-500); }
.radio-card:has(input:checked) {
  border-color: var(--color-navy-700); background: var(--color-navy-100);
}

.extra-panel { display: none; }
.extra-panel.active { display: block; }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 0.5rem;
  border: 0; border-radius: var(--radius-sm); font: inherit; font-weight: 700;
  padding: 0.85rem 1.4rem; cursor: pointer; font-size: 0.95rem; transition: transform 0.05s ease, filter 0.15s ease;
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--color-green-600); color: #fff; width: 100%; }
.btn-primary:hover { filter: brightness(1.06); text-decoration: none; }
.btn-secondary {
  background: transparent; color: var(--color-navy-800); border: 1.5px solid var(--color-ink-100);
}
.btn-secondary:hover { border-color: var(--color-navy-700); text-decoration: none; }

/* ------------------------------- Results panel ------------------------------ */

.results-card { position: sticky; top: 90px; }

.results-headline {
  display: grid; grid-template-columns: repeat(2, 1fr); gap: 0.9rem; margin-bottom: 1.1rem;
}
.stat {
  background: var(--color-navy-50); border-radius: var(--radius-md); padding: 0.9rem 1rem;
  border: 1px solid var(--color-navy-100);
}
.stat.stat-savings { background: var(--color-green-100); border-color: #bfe9d3; }
.stat .stat-label { font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.04em; color: var(--color-ink-500); font-weight: 700; }
.stat .stat-value { font-size: 1.35rem; font-weight: 800; color: var(--color-navy-950); margin-top: 0.15rem; }
.stat.stat-savings .stat-value { color: var(--color-green-700); }

.chart-wrap { background: var(--color-ink-50); border-radius: var(--radius-md); padding: 0.9rem; margin: 1rem 0; }
.chart-wrap canvas { width: 100% !important; height: 240px !important; }

.compare-table { width: 100%; border-collapse: collapse; font-size: 0.87rem; margin-top: 0.5rem; }
.compare-table th, .compare-table td { padding: 0.55rem 0.5rem; border-bottom: 1px solid var(--color-ink-100); text-align: right; }
.compare-table th:first-child, .compare-table td:first-child { text-align: left; color: var(--color-ink-700); }
.compare-table thead th { font-size: 0.72rem; text-transform: uppercase; color: var(--color-ink-500); }
.compare-table tbody tr:last-child td { font-weight: 700; color: var(--color-navy-950); border-bottom: none; }

.assumption-note {
  font-size: 0.8rem; color: var(--color-ink-500); background: var(--color-amber-100);
  border: 1px solid #f2ddb2; border-radius: var(--radius-sm); padding: 0.7rem 0.9rem; margin-top: 1rem;
}
.assumption-note strong { color: var(--color-amber-600); }

/* ------------------------------- Schedule table ------------------------------ */

.schedule-section { margin-top: 2rem; }
.table-scroll { overflow-x: auto; border: 1px solid var(--color-ink-100); border-radius: var(--radius-md); }
table.amort {
  width: 100%; border-collapse: collapse; font-size: 0.85rem; min-width: 640px;
}
table.amort th, table.amort td { padding: 0.55rem 0.75rem; text-align: right; border-bottom: 1px solid var(--color-ink-50); }
table.amort th:first-child, table.amort td:first-child { text-align: left; }
table.amort thead th {
  background: var(--color-navy-950); color: #fff; position: sticky; top: 0; font-weight: 600; font-size: 0.78rem;
}
table.amort tbody tr:nth-child(even) { background: var(--color-ink-50); }
table.amort td.extra-cell { color: var(--color-green-700); font-weight: 600; }

.table-controls { display: flex; align-items: center; justify-content: space-between; gap: 1rem; margin: 0.9rem 0; flex-wrap: wrap; }

/* ---------------------------------- Sections --------------------------------- */

section.content-block { padding: 3rem 0; }
section.content-block.alt { background: var(--color-ink-50); }
.section-heading { max-width: 70ch; margin-bottom: 1.75rem; }
.section-heading p { font-size: 1.02rem; }

.grid-3 { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 1.25rem; }
.info-card {
  border: 1px solid var(--color-ink-100); border-radius: var(--radius-md); padding: 1.25rem;
  background: #fff;
}
.info-card .icon {
  width: 42px; height: 42px; border-radius: 10px; background: var(--color-navy-100);
  color: var(--color-navy-800); display: flex; align-items: center; justify-content: center; margin-bottom: 0.75rem;
}

.country-tabs { display: flex; gap: 0.5rem; flex-wrap: wrap; margin-bottom: 1.5rem; }
.country-tabs button {
  border: 1.5px solid var(--color-ink-100); background: #fff; border-radius: 999px;
  padding: 0.5rem 1rem; font: inherit; font-weight: 700; font-size: 0.85rem; cursor: pointer; color: var(--color-ink-700);
}
.country-tabs button[aria-pressed="true"] { background: var(--color-navy-900); border-color: var(--color-navy-900); color: #fff; }
.country-panel { display: none; }
.country-panel.active { display: block; }

/* FAQ accordion */
.faq-item { border-bottom: 1px solid var(--color-ink-100); }
.faq-item summary {
  cursor: pointer; padding: 1rem 0; font-weight: 700; color: var(--color-navy-950);
  list-style: none; display: flex; justify-content: space-between; align-items: center; gap: 1rem;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: "+"; font-size: 1.4rem; color: var(--color-navy-700); flex-shrink: 0; font-weight: 400;
}
.faq-item[open] summary::after { content: "\2212"; }
.faq-item .faq-answer { padding: 0 0 1.1rem; color: var(--color-ink-700); }

/* Ad placeholder slots */
.ad-slot {
  background: var(--color-ink-50); border: 1px dashed var(--color-ink-300); border-radius: var(--radius-md);
  color: var(--color-ink-500); font-size: 0.78rem; text-align: center; padding: 1rem;
  min-height: 100px; display: flex; align-items: center; justify-content: center; margin: 2rem 0;
}

/* Article / guide pages */
.article-header { background: var(--color-navy-950); color: #fff; padding: 2.5rem 0 2rem; }
.article-header .eyebrow { color: var(--color-green-500); font-weight: 700; font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.06em; }
.article-header h1 { color: #fff; }
.article-meta { color: var(--color-navy-100); font-size: 0.85rem; }

.article-body { max-width: 74ch; margin: 0 auto; padding: 2.5rem 1.25rem; }
.article-body h2 { margin-top: 2em; }
.article-body h3 { margin-top: 1.5em; }
.article-body ul, .article-body ol { color: var(--color-ink-700); padding-left: 1.3em; }
.article-body li { margin-bottom: 0.4em; }
.article-body blockquote {
  margin: 1.5em 0; padding: 0.9em 1.2em; border-left: 4px solid var(--color-green-600);
  background: var(--color-green-100); border-radius: 0 8px 8px 0; color: var(--color-ink-900);
}
.article-body table { width: 100%; border-collapse: collapse; margin: 1.5em 0; font-size: 0.9rem; }
.article-body th, .article-body td { border: 1px solid var(--color-ink-100); padding: 0.5em 0.7em; text-align: left; }
.article-body th { background: var(--color-ink-50); }

.breadcrumbs { font-size: 0.8rem; color: var(--color-navy-100); }
.breadcrumbs a { color: var(--color-navy-100); }
.breadcrumbs span[aria-hidden] { margin: 0 0.4em; opacity: 0.6; }

.related-links { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 1rem; margin-top: 1rem; }
.related-links a {
  display: block; border: 1px solid var(--color-ink-100); border-radius: var(--radius-md);
  padding: 1rem; font-weight: 700; color: var(--color-navy-950);
}
.related-links a:hover { border-color: var(--color-navy-700); text-decoration: none; }
.related-links a small { display: block; font-weight: 500; color: var(--color-ink-500); margin-top: 0.3rem; }

/* Legal pages */
.legal-body { max-width: 78ch; margin: 0 auto; padding: 2.5rem 1.25rem; }
.legal-body h2 { margin-top: 1.75em; }

/* CTA band */
.cta-band {
  background: linear-gradient(120deg, var(--color-navy-900), var(--color-navy-700));
  color: #fff; border-radius: var(--radius-lg); padding: 2.25rem; text-align: center;
}
.cta-band h2 { color: #fff; }
.cta-band p { color: var(--color-navy-100); max-width: 60ch; margin-left: auto; margin-right: auto; }

/* ---------------------------------- Footer ----------------------------------- */

.site-footer { background: var(--color-navy-950); color: var(--color-navy-100); padding: 3rem 0 1.5rem; margin-top: 3rem; }
.footer-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 2rem; padding-bottom: 2rem; border-bottom: 1px solid rgba(255,255,255,0.1); }
.footer-grid h4 { color: #fff; font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 0.9rem; }
.footer-grid ul { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 0.55rem; }
.footer-grid a { color: var(--color-navy-100); font-size: 0.9rem; }
.footer-grid a:hover { color: #fff; }
.footer-bottom { display: flex; flex-wrap: wrap; gap: 0.75rem 1.5rem; justify-content: space-between; padding-top: 1.25rem; font-size: 0.8rem; color: var(--color-ink-300); }
.footer-disclaimer { font-size: 0.78rem; color: var(--color-ink-300); max-width: 90ch; margin-top: 1.25rem; }

@media (max-width: 640px) {
  .results-headline { grid-template-columns: 1fr 1fr; }
  .results-card { position: static; }
  .card { padding: 1.15rem; }
}