:root {
    --bg: #F4EFE6;
    --bg-card: #FBF8F2;
    --ink: #1A1814;
    --ink-soft: #4A453D;
    --ink-muted: #8C8578;
    --accent: #B8412C;
    --accent-deep: #8A2F1F;
    --accent-soft: #E8D5CC;
    --rule: #1A1814;
    --grid: #D9D2C4;
    --principal: #1A1814;
    --interest: #B8412C;
  }

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

  html, body {
    background: var(--bg);
    color: var(--ink);
    font-family: 'Inter Tight', sans-serif;
    font-size: 15px;
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
  }

  body {
    background-image:
      radial-gradient(circle at 1px 1px, rgba(26,24,20,0.04) 1px, transparent 0);
    background-size: 24px 24px;
    min-height: 100vh;
    padding: 32px 24px 80px;
  }

  .frame {
    max-width: 1240px;
    margin: 0 auto;
  }

  /* ============ MASTHEAD ============ */
  .masthead {
    border-top: 3px solid var(--rule);
    border-bottom: 1px solid var(--rule);
    padding: 20px 0 16px;
    margin-bottom: 32px;
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    gap: 24px;
    flex-wrap: wrap;
  }

  .masthead .edition {
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--ink-soft);
  }

  .masthead-back {
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--accent);
    text-decoration: none;
  }

  .masthead-back:hover {
    color: var(--accent-deep);
  }

  .masthead .date {
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--ink-soft);
  }

  .title-block {
    text-align: center;
    padding: 36px 0 28px;
    border-bottom: 1px solid var(--rule);
    margin-bottom: 40px;
    position: relative;
  }

  .title-block .kicker {
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    letter-spacing: 0.24em;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 16px;
  }

  .title-block h1 {
    font-family: 'Fraunces', serif;
    font-weight: 300;
    font-size: clamp(48px, 8vw, 104px);
    line-height: 0.95;
    letter-spacing: -0.03em;
    font-variation-settings: 'opsz' 144;
  }

  .title-block h1 em {
    font-style: italic;
    font-weight: 400;
    color: var(--accent);
  }

  .title-block .dek {
    font-family: 'Fraunces', serif;
    font-style: italic;
    font-weight: 400;
    font-size: 18px;
    color: var(--ink-soft);
    margin-top: 18px;
    max-width: 540px;
    margin-left: auto;
    margin-right: auto;
  }

  /* ============ LAYOUT ============ */
  .grid {
    display: grid;
    grid-template-columns: 380px 1fr;
    gap: 40px;
    align-items: start;
  }

  /* ============ INPUT PANEL ============ */
  .controls {
    background: var(--bg-card);
    border: 1px solid var(--rule);
    padding: 32px 28px;
    position: sticky;
    top: 24px;
  }

  .controls .section-label {
    font-family: 'JetBrains Mono', monospace;
    font-size: 10px;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--ink-muted);
    margin-bottom: 24px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--grid);
    display: flex;
    justify-content: space-between;
  }

  .field {
    margin-bottom: 22px;
  }

  .field label {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    font-family: 'JetBrains Mono', monospace;
    font-size: 10px;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    color: var(--ink-soft);
    margin-bottom: 8px;
  }

  .field label .hint {
    color: var(--ink-muted);
    letter-spacing: 0.08em;
    text-transform: none;
  }

  .input-wrap {
    position: relative;
  }

  .input-wrap .prefix,
  .input-wrap .suffix {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    font-family: 'Fraunces', serif;
    font-size: 22px;
    color: var(--ink-muted);
    pointer-events: none;
  }

  .input-wrap .prefix { left: 14px; }
  .input-wrap .suffix { right: 14px; }

  input[type="text"], input[type="number"], select {
    width: 100%;
    background: transparent;
    border: 1px solid var(--grid);
    border-radius: 0;
    padding: 12px 14px;
    font-family: 'Fraunces', serif;
    font-weight: 400;
    font-size: 22px;
    color: var(--ink);
    letter-spacing: -0.01em;
    transition: border-color 0.2s, background 0.2s;
    appearance: none;
    -moz-appearance: textfield;
  }

  input[type="number"]::-webkit-outer-spin-button,
  input[type="number"]::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
  }

  .input-wrap.has-prefix input { padding-left: 30px; }
  .input-wrap.has-suffix input { padding-right: 30px; }

  input:focus, select:focus {
    outline: none;
    border-color: var(--accent);
    background: #fff;
  }

  select {
    cursor: pointer;
    background-image: url("data:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%231A1814' stroke-width='1.5' fill='none'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 14px center;
    padding-right: 36px;
  }

  /* ============ RESULTS ============ */
  .results-pane {
    display: flex;
    flex-direction: column;
    gap: 32px;
  }

  .headline-result {
    background: var(--bg-card);
    border: 1px solid var(--rule);
    padding: 36px 32px;
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: end;
    gap: 24px;
    position: relative;
    overflow: hidden;
  }

  .headline-result::before {
    content: '';
    position: absolute;
    top: 0; left: 0;
    width: 6px;
    height: 100%;
    background: var(--accent);
  }

  .headline-result .label {
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--ink-soft);
    margin-bottom: 8px;
  }

  .headline-result .figure {
    font-family: 'Fraunces', serif;
    font-weight: 300;
    font-size: clamp(48px, 7vw, 84px);
    line-height: 1;
    letter-spacing: -0.035em;
    font-variation-settings: 'opsz' 144;
  }

  .headline-result .figure .cents {
    font-size: 0.45em;
    color: var(--ink-muted);
    vertical-align: top;
    margin-left: 4px;
    letter-spacing: 0;
  }

  .headline-result .figure .unit {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.16em;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--ink-soft);
    display: block;
    margin-top: 10px;
  }

  .seal {
    width: 88px;
    height: 88px;
    border: 1px solid var(--ink);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    flex-shrink: 0;
  }

  .seal-inner {
    width: 76px;
    height: 76px;
    border: 1px solid var(--ink);
    border-radius: 50%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    font-family: 'JetBrains Mono', monospace;
    font-size: 8px;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    line-height: 1.3;
  }

  .seal-inner .term {
    font-family: 'Fraunces', serif;
    font-style: italic;
    font-size: 22px;
    letter-spacing: 0;
    text-transform: none;
    line-height: 1;
    margin: 2px 0;
    font-weight: 500;
  }

  /* ============ STATS ROW ============ */
  .stats-row {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0;
    border: 1px solid var(--rule);
    background: var(--bg-card);
  }

  @media (max-width: 640px) {
    .stats-row { grid-template-columns: 1fr; }
  }

  .stat {
    padding: 24px 22px;
    border-right: 1px solid var(--grid);
  }

  .stat:last-child { border-right: none; }

  @media (max-width: 640px) {
    .stat { border-right: none; border-bottom: 1px solid var(--grid); }
    .stat:last-child { border-bottom: none; }
  }

  .stat .stat-label {
    font-family: 'JetBrains Mono', monospace;
    font-size: 10px;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--ink-soft);
    margin-bottom: 10px;
  }

  .stat .stat-value {
    font-family: 'Fraunces', serif;
    font-weight: 400;
    font-size: 28px;
    line-height: 1.1;
    letter-spacing: -0.02em;
  }

  .stat .stat-detail {
    font-family: 'Inter Tight', sans-serif;
    font-size: 12px;
    color: var(--ink-muted);
    margin-top: 4px;
  }

  /* ============ CHART ============ */
  .chart-card {
    background: var(--bg-card);
    border: 1px solid var(--rule);
    padding: 28px 28px 24px;
  }

  .chart-header {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    padding-bottom: 18px;
    border-bottom: 1px solid var(--grid);
    margin-bottom: 24px;
    flex-wrap: wrap;
    gap: 12px;
  }

  .chart-title {
    font-family: 'Fraunces', serif;
    font-style: italic;
    font-weight: 400;
    font-size: 22px;
    letter-spacing: -0.01em;
  }

  .legend {
    display: flex;
    gap: 20px;
  }

  .legend-item {
    display: flex;
    align-items: center;
    gap: 8px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 10px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--ink-soft);
  }

  .legend-swatch {
    width: 14px;
    height: 14px;
    border: 1px solid var(--rule);
  }

  .chart-wrap {
    position: relative;
    height: 320px;
  }

  /* ============ AMORTIZATION ============ */
  .table-card {
    background: var(--bg-card);
    border: 1px solid var(--rule);
  }

  .table-header {
    padding: 24px 28px 18px;
    border-bottom: 1px solid var(--rule);
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    flex-wrap: wrap;
    gap: 12px;
  }

  .table-title {
    font-family: 'Fraunces', serif;
    font-style: italic;
    font-weight: 400;
    font-size: 22px;
  }

  .view-toggle {
    display: flex;
    border: 1px solid var(--rule);
  }

  .view-toggle button {
    background: transparent;
    border: none;
    padding: 8px 16px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 10px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--ink-soft);
    cursor: pointer;
    transition: background 0.15s, color 0.15s;
  }

  .view-toggle button + button {
    border-left: 1px solid var(--rule);
  }

  .view-toggle button.active {
    background: var(--ink);
    color: var(--bg);
  }

  .table-scroll {
    max-height: 480px;
    overflow-y: auto;
  }

  table {
    width: 100%;
    border-collapse: collapse;
    font-family: 'JetBrains Mono', monospace;
    font-size: 13px;
  }

  thead th {
    background: var(--bg-card);
    position: sticky;
    top: 0;
    text-align: right;
    padding: 14px 20px;
    font-size: 10px;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    color: var(--ink-soft);
    border-bottom: 1px solid var(--rule);
    font-weight: 500;
  }

  thead th:first-child { text-align: left; }

  tbody td {
    padding: 12px 20px;
    text-align: right;
    border-bottom: 1px solid var(--grid);
    color: var(--ink);
  }

  tbody td:first-child {
    text-align: left;
    color: var(--ink-soft);
  }

  tbody tr:hover td {
    background: rgba(184, 65, 44, 0.05);
  }

  tbody tr.year-row td {
    background: rgba(26, 24, 20, 0.03);
    font-weight: 500;
  }

  .balance-bar {
    display: inline-block;
    width: 60px;
    height: 6px;
    background: var(--grid);
    margin-left: 10px;
    vertical-align: middle;
    position: relative;
  }

  .balance-bar::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    background: var(--accent);
    width: var(--w, 100%);
  }

  /* ============ FOOTER ============ */
  .colophon {
    margin-top: 48px;
    padding-top: 24px;
    border-top: 1px solid var(--rule);
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    font-family: 'JetBrains Mono', monospace;
    font-size: 10px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--ink-muted);
    flex-wrap: wrap;
    gap: 12px;
  }

  .colophon em {
    font-family: 'Fraunces', serif;
    font-style: italic;
    text-transform: none;
    letter-spacing: 0;
    font-size: 13px;
    color: var(--ink-soft);
  }

  /* ============ RESPONSIVE ============ */
  @media (max-width: 920px) {
    .grid { grid-template-columns: 1fr; gap: 32px; }
    .grid > * { min-width: 0; }
    .controls { position: static; }
  }

  @media (max-width: 480px) {
    body { padding: 16px 14px 60px; }
    .controls { padding: 22px 18px; }
    .headline-result { padding: 22px 18px; grid-template-columns: 1fr; }
    .seal { display: none; }
    .headline-result .figure { font-size: clamp(36px, 10vw, 60px); }
    .title-block h1 { font-size: clamp(36px, 10vw, 60px); }
    .title-block { padding: 24px 0 20px; margin-bottom: 28px; }
    .chart-wrap { height: 220px; }
    .chart-card { padding: 20px 16px 18px; }
    .stat .stat-value { font-size: 22px; }
    input[type="text"], input[type="number"], select { font-size: 18px; }
    .table-card { overflow-x: auto; }
    .table-scroll { overflow-x: visible; }
    .table-header { padding: 16px 16px 12px; }
    thead th { padding: 10px 10px; font-size: 9px; }
    tbody td { padding: 9px 10px; }
    table { font-size: 11px; min-width: 360px; }
  }

  /* ============ ANIMATIONS ============ */
  @keyframes fadeUp {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
  }

  .title-block, .controls, .headline-result, .stats-row, .chart-card, .table-card {
    animation: fadeUp 0.6s ease-out both;
  }
  .controls { animation-delay: 0.05s; }
  .headline-result { animation-delay: 0.1s; }
  .stats-row { animation-delay: 0.15s; }
  .chart-card { animation-delay: 0.2s; }
  .table-card { animation-delay: 0.25s; }

  /* Scrollbar */
  .table-scroll::-webkit-scrollbar { width: 8px; }
  .table-scroll::-webkit-scrollbar-track { background: var(--bg-card); }
  .table-scroll::-webkit-scrollbar-thumb { background: var(--grid); }
  .table-scroll::-webkit-scrollbar-thumb:hover { background: var(--ink-muted); }

  .legend-swatch-balance  { background: #1A1814; }
  .legend-swatch-interest { background: #B8412C; }