/* ===========================
   Tokens
   =========================== */
:root {
  /* color */
  --navy: #1B2A4A;
  --cream: #F7F3EA;
  --ink: #4A463C;
  --muted: #6B6559;
  --accent: #C68A2E;         /* FILLS AND DECORATION ONLY */
  --accent-ink: #8A5A12;     /* TEXT AND LINKS on cream */
  --accent-on: #412402;      /* text placed on an --accent fill */
  --green: #2E5D4B;
  --card: #FFFDF8;
  --border: #E4DDCC;
  --border-strong: #D9D2C2;
  --highlight: #FAEFD9;      /* row highlight on cream/card */

  /* tax bracket colours: distinct hues, ordered so neighbouring brackets stay
     distinguishable (validated incl. colour-blindness). Fills only, never text. */
  --band-1: #eb6834;
  --band-2: #1baf7a;
  --band-3: #008300;
  --band-4: #e87ba4;
  --band-5: #eda100;
  --band-6: #e34948;
  --band-7: #4a3aa7;
  --band-8: #2a78d6;
  --band-9: #8a5a12;

  /* type */
  --font-serif: ui-serif, Georgia, "Times New Roman", serif;
  --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;

  /* scale, base 18px */
  --fs-body: 18px;
  --fs-small: 15px;
  --fs-h3: 21px;
  --fs-h2: 28px;
  --fs-h1: 38px;
  --fs-hero: 48px;
  --lh-body: 1.6;
  --lh-hero: 1.08;
}

/* ===========================
   Reset
   =========================== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

/* ===========================
   Base
   =========================== */
html {
  font-size: var(--fs-body);
  background: var(--cream);
  color: var(--ink);
  font-family: var(--font-sans);
  line-height: var(--lh-body);
  -webkit-font-smoothing: antialiased;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
}

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

a {
  color: var(--accent-ink);
  text-underline-offset: 2px;
}

a:hover {
  color: var(--navy);
}

/* ===========================
   Layout
   =========================== */
.container {
  max-width: 780px;
  margin-inline: auto;
  padding-inline: 1.5rem;
}

section {
  padding-block: 1.75rem 2rem;
}

section + section {
  border-top: 1px solid var(--border);
}

/* ===========================
   Typography
   =========================== */
h1, h2, h3 {
  font-family: var(--font-serif);
  font-weight: 400;
  line-height: 1.15;
  color: var(--navy);
}

h1 { font-size: var(--fs-h1); }
h2 { font-size: var(--fs-h2); margin-block-end: 0.5em; }
h3 { font-size: var(--fs-h3); }

.hero-headline {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: var(--fs-hero);
  line-height: var(--lh-hero);
  color: var(--navy);
}

p { margin-block-start: 1em; }
p:first-child { margin-block-start: 0; }

.text-muted {
  color: var(--muted);
  font-size: var(--fs-small);
}

/* ===========================
   Buttons
   =========================== */
.btn {
  display: inline-block;
  padding: 0.75rem 1.75rem;
  border-radius: 4px;
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  font-weight: 500;
  text-align: center;
  text-decoration: none;
  cursor: pointer;
  transition: opacity 0.15s;
  line-height: 1;
}

.btn:hover {
  opacity: 0.85;
}

.btn-primary {
  background: var(--navy);
  color: var(--cream);
}

.btn-primary:hover {
  color: var(--cream);
}

.btn-ghost {
  color: var(--accent-ink);
  text-decoration: underline;
  padding: 0.75rem 0;
  font-weight: 400;
}

/* ===========================
   Header
   =========================== */
.site-header {
  background: var(--cream);
  border-bottom: 1px solid var(--border);
  padding-block: 1rem;
  position: sticky;
  top: 0;
  z-index: 10;
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.site-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  flex-shrink: 0;
}

.wordmark {
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: 1rem;
  color: var(--navy);
  white-space: nowrap;
}

.site-header nav {
  display: flex;
  gap: 1.5rem;
}

.site-header nav a {
  font-family: var(--font-sans);
  font-size: var(--fs-small);
  font-weight: 500;
  color: var(--navy);
  text-decoration: none;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  white-space: nowrap;
}

.site-header nav a:hover {
  color: var(--accent-ink);
}

/* ===========================
   Hero
   =========================== */
.hero {
  padding-block: 2rem;
}

.hero-subhead {
  font-size: var(--fs-h3);
  color: var(--ink);
  margin-block: 1rem 0;
  max-width: 52ch;
  line-height: 1.4;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 2rem;
  flex-wrap: wrap;
  margin-top: 1.5rem;
}

/* ===========================
   Footer
   =========================== */
.site-footer {
  border-top: 1px solid var(--border);
  padding-block: 2rem;
}

.site-footer p {
  font-size: var(--fs-small);
  color: var(--muted);
  margin: 0;
}

.site-footer a {
  color: var(--muted);
}

.site-footer a:hover {
  color: var(--navy);
}

/* ===========================
   Privacy / prose pages
   =========================== */
.prose {
  max-width: 65ch;
}

.prose h1 {
  margin-block-end: 1.5rem;
}

.prose h2 {
  margin-block: 1.75rem 0.5em;
}

.prose h2:first-child {
  margin-block-start: 0;
}

.prose p {
  margin-block-start: 1em;
}

.prose p:first-of-type {
  margin-block-start: 0;
}

.prose ul {
  margin-block-start: 0.75rem;
  padding-left: 1.5rem;
}

.prose li + li {
  margin-block-start: 0.4rem;
}

/* ===========================
   Calculator
   =========================== */
.calc-form {
  display: grid;
  gap: 1.5rem;
  margin-block-start: 1.25rem;
}

.calc-form fieldset {
  border: 0;
}

.calc-form legend {
  font-family: var(--font-serif);
  font-size: var(--fs-h3);
  color: var(--navy);
  margin-block-end: 0.75rem;
}

.field-hint {
  font-size: var(--fs-small);
  color: var(--muted);
  margin-block: -0.5rem 1rem;
}

.check {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.6rem;
  margin-block-start: 1rem;
}

.check .field-hint {
  flex-basis: 100%;
  margin: 0.25rem 0 0 1.7rem;
}

.check input {
  width: 1.1rem;
  height: 1.1rem;
  accent-color: var(--navy);
}

.incomes {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem 1.5rem;
}

.incomes legend,
.incomes .field-hint {
  grid-column: 1 / -1;
}

.field label {
  display: block;
  font-size: var(--fs-small);
  font-weight: 500;
  color: var(--navy);
  margin-block-end: 0.3rem;
}

.money-wrap {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--card);
  border: 1px solid var(--border-strong);
  border-radius: 4px;
  padding-inline: 0.75rem;
}

.money-wrap:focus-within {
  border-color: var(--navy);
  outline: 2px solid var(--navy);
}

.money-wrap span {
  color: var(--muted);
}

.money {
  flex: 1;
  min-width: 0;
  border: 0;
  background: transparent;
  font: inherit;
  color: var(--ink);
  padding-block: 0.6rem;
  text-align: right;
  font-variant-numeric: tabular-nums;
}

.money:focus {
  outline: none;
}

/* Results */
.results {
  margin-block-start: 2rem;
}

.summary-total {
  font-size: var(--fs-h3);
  font-family: var(--font-serif);
  color: var(--navy);
}

.summary-total span {
  font-variant-numeric: tabular-nums;
}

.summary-cols {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-block-start: 1rem;
}

.summary-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 1.25rem 1.4rem;
  display: grid;
  gap: 0.6rem;
}

.summary-card h3 {
  margin-block-end: 0.1rem;
}

.summary-card > div {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1rem;
}

.summary-card dt {
  font-size: var(--fs-small);
  color: var(--muted);
}

.summary-card dd {
  color: var(--navy);
  font-variant-numeric: tabular-nums;
}

.summary-card .summary-rate dd {
  font-family: var(--font-serif);
  font-size: var(--fs-h2);
  line-height: 1.1;
}

.compare-diff {
  margin-block-start: 1rem;
  color: var(--green);
  font-weight: 500;
}

/* Chart */
.chart-card {
  margin-block-start: 1.5rem;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.5rem;
}

.chart-sub {
  font-size: var(--fs-small);
  color: var(--muted);
  margin-block-start: 0.35rem;
}

.chart-callout {
  margin-block-start: 0.75rem;
  color: var(--navy);
  font-weight: 500;
}

.chart-callout:empty {
  display: none;
}

.chart {
  margin-block-start: 1.5rem;
}

.chart-empty {
  color: var(--muted);
}

.vchart-plot {
  display: grid;
  grid-template-columns: 4.5rem 1fr 3.25rem;
}

.vchart-axis,
.vchart-rates {
  position: relative;
  font-size: 13px;
  font-variant-numeric: tabular-nums;
  line-height: 1;
}

.vchart-tick,
.vchart-rate {
  position: absolute;
  white-space: nowrap;
}

.vchart-tick {
  right: 0.5rem;
  color: var(--muted);
}

.vchart-rate {
  left: 0.5rem;
  color: var(--ink);
  font-weight: 500;
}

.vchart-area {
  position: relative;
  border-bottom: 1px solid var(--muted);
}

/* Background stripe per bracket, tinted with its colour */
.vband {
  position: absolute;
  left: 0;
  right: 0;
  border-top: 1px dashed var(--border-strong);
}

.vband.band-1 { background: color-mix(in srgb, var(--band-1) 12%, var(--card)); }
.vband.band-2 { background: color-mix(in srgb, var(--band-2) 12%, var(--card)); }
.vband.band-3 { background: color-mix(in srgb, var(--band-3) 12%, var(--card)); }
.vband.band-4 { background: color-mix(in srgb, var(--band-4) 12%, var(--card)); }
.vband.band-5 { background: color-mix(in srgb, var(--band-5) 12%, var(--card)); }
.vband.band-6 { background: color-mix(in srgb, var(--band-6) 12%, var(--card)); }
.vband.band-7 { background: color-mix(in srgb, var(--band-7) 12%, var(--card)); }
.vband.band-8 { background: color-mix(in srgb, var(--band-8) 12%, var(--card)); }
.vband.band-9 { background: color-mix(in srgb, var(--band-9) 12%, var(--card)); }

.vchart-cols,
.vchart-labels {
  display: grid;
  grid-template-columns: 1fr 0.6fr 2fr;
  column-gap: 0;
}

.vchart-cols {
  position: absolute;
  inset: 0;
  grid-template-columns: 1fr 0.6fr 1fr 1fr;
  column-gap: 0;
  padding-inline: 4%;
}

.vcol {
  position: relative;
  display: flex;
  align-items: flex-end;
  justify-content: center;
}

.vcol-stack {
  display: flex;
  flex-direction: column-reverse;
  width: min(72px, 70%);
  border-radius: 4px 4px 0 0;
  overflow: hidden;
  transition: height 0.25s ease;
}

.vseg {
  flex-basis: 0;
  min-height: 2px;
  border-top: 2px solid var(--card);
}

.vseg:last-child {
  border-top: 0;
}

.vseg:hover,
.vseg:focus-visible {
  outline: 2px solid var(--navy);
  outline-offset: -2px;
}

.vchart-labels {
  margin-inline: 4.5rem 3.25rem;
  padding-inline: 4%;
  margin-block-start: 0.6rem;
  grid-template-columns: 1fr 0.6fr 2fr;
}

.vchart-group {
  display: flex;
  flex-direction: column;
  align-items: center;
  border-top: 2px solid var(--navy);
  padding-block-start: 0.4rem;
  order: 0;
}

.vchart-group-name {
  font-size: var(--fs-small);
  color: var(--navy);
  font-weight: 500;
  white-space: nowrap;
}

.vchart-pair {
  display: grid;
  grid-template-columns: 1fr 1fr;
  width: 100%;
}

.vcol-label {
  display: flex;
  flex-direction: column;
  align-items: center;
  font-size: var(--fs-small);
  line-height: 1.3;
  text-align: center;
}

.vchart-labels > .vcol-label {
  padding-block-start: calc(0.4rem + 2px);
}

.vcol-name {
  color: var(--ink);
  font-weight: 500;
}

.vcol-value {
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}

.band-1 { background: var(--band-1); }
.band-2 { background: var(--band-2); }
.band-3 { background: var(--band-3); }
.band-4 { background: var(--band-4); }
.band-5 { background: var(--band-5); }
.band-6 { background: var(--band-6); }
.band-7 { background: var(--band-7); }
.band-8 { background: var(--band-8); }
.band-9 { background: var(--band-9); }

.legend {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 1rem;
  margin-block-start: 1.25rem;
  font-size: var(--fs-small);
  color: var(--ink);
}

.legend li {
  display: flex;
  align-items: center;
}

.swatch {
  display: inline-block;
  width: 12px;
  height: 12px;
  border-radius: 2px;
  margin-inline-end: 0.45rem;
  vertical-align: -1px;
  flex-shrink: 0;
}

.chart-tip {
  position: absolute;
  z-index: 20;
  background: var(--navy);
  color: var(--cream);
  font-size: var(--fs-small);
  line-height: 1.4;
  padding: 0.5rem 0.75rem;
  border-radius: 4px;
  white-space: pre-line;
  pointer-events: none;
}

/* Tables */
.table-title {
  margin-block: 1.75rem 0.6rem;
}

.table-wrap {
  overflow-x: auto;
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--card);
  border: 1px solid var(--border);
  font-size: var(--fs-small);
  font-variant-numeric: tabular-nums;
}

.data-table th,
.data-table td {
  padding: 0.6rem 0.9rem;
  border-bottom: 1px solid var(--border);
  text-align: left;
  font-weight: 400;
}

.data-table thead th.num {
  white-space: normal;
}

.data-table thead th {
  font-weight: 500;
  color: var(--muted);
  border-bottom-color: var(--border-strong);
}

.data-table .num {
  text-align: right;
  white-space: nowrap;
}

.data-table tbody th {
  color: var(--ink);
}

.brackets tbody th {
  white-space: nowrap;
}

.data-table tr.unused th,
.data-table tr.unused td {
  color: var(--muted);
}

.data-table tr.unused .swatch {
  opacity: 0.35;
}

.data-table .group-start {
  border-left: 1px solid var(--border-strong);
}

.data-table .group-head th {
  text-align: center;
  color: var(--navy);
  font-weight: 500;
}

.data-table .group-head td {
  border-bottom: 0;
}

.data-table tr.exposed th,
.data-table tr.exposed td {
  background: var(--highlight);
}

.table-note {
  font-size: var(--fs-small);
  color: var(--muted);
  margin-block: -0.25rem 0.75rem;
}

.data-table tr.total th,
.data-table tr.total td {
  font-weight: 600;
  color: var(--navy);
  border-top: 2px solid var(--border-strong);
}

.data-table tfoot th {
  text-align: right;
}

.categories-table {
  min-width: 560px;
}

.categories-table th,
.categories-table td {
  vertical-align: top;
}

.categories-table tbody th {
  white-space: nowrap;
  font-weight: 500;
  color: var(--navy);
}

.categories-table strong {
  font-weight: 500;
  color: var(--navy);
}

.categories-table em {
  color: var(--muted);
}

.prose .categories-table ul {
  margin: 0;
  padding-left: 1rem;
}

.prose .categories-table li + li {
  margin-block-start: 0.25rem;
}

.prose .table-wrap {
  margin-block: 1rem 1.5rem;
}

.prose h3 {
  margin-block: 1.5rem 0.5rem;
}

.prose ol {
  margin-block-start: 0.75rem;
  padding-left: 1.5rem;
}

.hero-subhead.prose p {
  margin-block-start: 1em;
}

/* ===========================
   Responsive
   =========================== */
@media (max-width: 640px) {
  .hero-headline {
    font-size: 34px;
  }

  h1 {
    font-size: 30px;
  }


  .incomes {
    grid-template-columns: 1fr;
  }

  .summary-cols {
    grid-template-columns: 1fr;
  }

  .site-header nav a + a {
    display: none;
  }

  .hero-actions {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.75rem;
  }

  section {
    padding-block: 1.25rem 1.5rem;
  }

  .hero {
    padding-block: 1.5rem;
  }
}