:root {
    --ink: #1C2B3A;
    --ink-deep: #121C26;
    --paper: #F2EFE6;
    --paper-dim: #E8E3D5;
    --rule: #3A4C5C;
    --rule-soft: rgba(58, 76, 92, 0.35);
    --brass: #C9A227;
    --brass-bright: #E0BC3F;
    --red-ink: #A63D40;
    --green-ink: #3D6B4F;
    --text-on-ink: #DCE3E8;
    --text-dim: #8CA0AC;
  }

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

  body {
    background: var(--ink);
    background-image:
      linear-gradient(var(--ink), var(--ink)),
      repeating-linear-gradient(0deg, transparent, transparent 27px, var(--rule-soft) 27px, var(--rule-soft) 28px);
    color: var(--text-on-ink);
    font-family: 'IBM Plex Sans', sans-serif;
    min-height: 100vh;
    padding: 48px 24px 80px;
  }

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

  header {
    margin-bottom: 44px;
    border-bottom: 1px solid var(--rule);
    padding-bottom: 28px;
  }

  .eyebrow {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 12px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--brass-bright);
    margin-bottom: 14px;
  }

  h1 {
    font-family: 'Fraunces', serif;
    font-weight: 500;
    font-size: clamp(32px, 5vw, 52px);
    line-height: 1.05;
    color: var(--text-on-ink);
    max-width: 720px;
  }

  h1 em {
    font-style: italic;
    color: var(--brass-bright);
  }

  .sub {
    margin-top: 16px;
    color: var(--text-dim);
    font-size: 15.5px;
    max-width: 560px;
    line-height: 1.55;
  }

  .grid {
    display: grid;
    grid-template-columns: 1.05fr 0.95fr;
    gap: 40px;
    align-items: start;
  }

  @media (max-width: 860px) {
    .grid { grid-template-columns: 1fr; }
  }

  /* --- LEDGER (inputs) --- */
  .ledger-label {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 11px;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--brass);
    margin-bottom: 20px;
  }

  .line-item {
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: end;
    gap: 16px;
    padding: 16px 0;
    border-bottom: 1px solid var(--rule);
  }

  .line-item label {
    font-size: 14.5px;
    color: var(--text-on-ink);
    line-height: 1.4;
  }

  .line-item .hint {
    display: block;
    font-size: 12.5px;
    color: var(--text-dim);
    margin-top: 3px;
    font-weight: 400;
  }

  .input-box {
    position: relative;
    display: flex;
    align-items: baseline;
  }

  .input-box .prefix, .input-box .suffix {
    font-family: 'IBM Plex Mono', monospace;
    color: var(--text-dim);
    font-size: 15px;
  }

  .input-box .prefix { margin-right: 4px; }
  .input-box .suffix { margin-left: 6px; }

  select {
    background: var(--ink);
    border: none;
    border-bottom: 1px solid var(--rule);
    color: var(--brass-bright);
    font-family: 'IBM Plex Mono', monospace;
    font-size: 14px;
    font-weight: 500;
    width: 240px;
    text-align: right;
    padding: 6px 2px 8px;
    transition: border-color 0.15s ease;
    -webkit-appearance: none;
    appearance: none;
    cursor: pointer;
  }

  select:focus {
    outline: none;
    border-bottom: 1px solid var(--brass);
  }

  select option {
    background: var(--ink);
    color: var(--text-on-ink);
  }

  .benchmark-note {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 12px;
    color: var(--text-dim);
    text-align: right;
    margin-top: 6px;
  }

  .benchmark-note span {
    color: var(--brass-bright);
  }

  input[type="number"] {
    background: transparent;
    border: none;
    border-bottom: 1px solid transparent;
    color: var(--brass-bright);
    font-family: 'IBM Plex Mono', monospace;
    font-size: 20px;
    font-weight: 500;
    width: 110px;
    text-align: right;
    padding: 2px 2px 4px;
    transition: border-color 0.15s ease;
  }

  input[type="number"]:focus {
    outline: none;
    border-bottom: 1px solid var(--brass);
  }

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

  .calc-btn {
    margin-top: 32px;
    width: 100%;
    padding: 16px;
    background: var(--brass);
    color: var(--ink-deep);
    border: none;
    font-family: 'IBM Plex Mono', monospace;
    font-size: 13px;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.15s ease, transform 0.1s ease;
  }

  .calc-btn:hover { background: var(--brass-bright); }
  .calc-btn:active { transform: scale(0.99); }

  /* --- INVOICE CARD (output) --- */
  .invoice-wrap {
    position: sticky;
    top: 40px;
  }

  .invoice {
    background: var(--paper);
    color: var(--ink-deep);
    padding: 40px 36px;
    position: relative;
    overflow: hidden;
    box-shadow: 0 24px 60px rgba(0,0,0,0.35);
    min-height: 460px;
    display: flex;
    flex-direction: column;
  }

  .invoice-head {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    border-bottom: 2px solid var(--ink-deep);
    padding-bottom: 14px;
    margin-bottom: 28px;
  }

  .invoice-head .doc-title {
    font-family: 'Fraunces', serif;
    font-size: 15px;
    letter-spacing: 0.04em;
  }

  .invoice-head .doc-no {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 11px;
    color: #6B7580;
  }

  .rate-display {
    text-align: center;
    padding: 20px 0 28px;
  }

  .rate-display .label {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 11px;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: #6B7580;
    margin-bottom: 10px;
  }

  .rate-display .number {
    font-family: 'Fraunces', serif;
    font-size: 64px;
    line-height: 1;
    color: var(--ink-deep);
    font-weight: 500;
  }

  .rate-display .number .cents {
    font-size: 32px;
    color: #6B7580;
  }

  .rate-display .per {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 13px;
    color: #6B7580;
    margin-top: 6px;
  }

  .breakdown {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 13px;
    border-top: 1px solid #C7C1AF;
    padding-top: 18px;
    display: flex;
    flex-direction: column;
    gap: 9px;
  }

  .breakdown-row {
    display: flex;
    justify-content: space-between;
    color: #4A5460;
  }

  .breakdown-row.total {
    color: var(--ink-deep);
    font-weight: 600;
    border-top: 1px dashed #C7C1AF;
    padding-top: 9px;
    margin-top: 2px;
  }

  .compare {
    margin-top: 24px;
    padding-top: 20px;
    border-top: 1px solid #C7C1AF;
  }

  .compare .compare-label {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 11px;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: #6B7580;
    margin-bottom: 10px;
  }

  .bar-row {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 8px;
  }

  .bar-track {
    flex: 1;
    height: 22px;
    background: #DEDACB;
    position: relative;
    overflow: hidden;
  }

  .bar-fill {
    height: 100%;
    transition: width 0.6s cubic-bezier(0.2, 0.8, 0.2, 1);
  }

  .bar-fill.current { background: var(--red-ink); }
  .bar-fill.true-rate { background: var(--green-ink); }
  .bar-fill.market { background: var(--brass); }

  .bar-tag {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 12px;
    width: 92px;
    color: #4A5460;
    flex-shrink: 0;
  }

  .bar-value {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 12px;
    width: 60px;
    text-align: right;
    flex-shrink: 0;
  }

  /* Stamp */
  .stamp {
    position: absolute;
    top: 44%;
    right: 8%;
    transform: translateY(-50%) rotate(-14deg) scale(0);
    border: 3px solid var(--red-ink);
    color: var(--red-ink);
    border-radius: 50%;
    width: 148px;
    height: 148px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    font-family: 'IBM Plex Mono', monospace;
    font-weight: 600;
    font-size: 13px;
    line-height: 1.3;
    letter-spacing: 0.03em;
    padding: 10px;
    pointer-events: none;
    opacity: 0;
    mix-blend-mode: multiply;
  }

  .stamp.ontrack {
    border-color: var(--green-ink);
    color: var(--green-ink);
  }

  .stamp::before {
    content: '';
    position: absolute;
    inset: 8px;
    border: 1px solid currentColor;
    border-radius: 50%;
  }

  .stamp.show {
    animation: stampDown 0.4s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
  }

  @keyframes stampDown {
    0% { transform: translateY(-50%) rotate(-14deg) scale(2.2); opacity: 0; }
    60% { opacity: 0.85; }
    100% { transform: translateY(-50%) rotate(-14deg) scale(1); opacity: 0.85; }
  }

  .empty-state {
    margin: auto;
    text-align: center;
    color: #8A8371;
    font-family: 'IBM Plex Mono', monospace;
    font-size: 13px;
    padding: 40px 20px;
    line-height: 1.6;
  }

  .ad-slot {
    margin: 32px 0;
    padding: 14px 0;
    border-top: 1px dashed var(--rule-soft);
    border-bottom: 1px dashed var(--rule-soft);
    text-align: center;
    min-height: 90px;
  }

  .ad-label {
    display: block;
    font-family: 'IBM Plex Mono', monospace;
    font-size: 10px;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--text-dim);
    margin-bottom: 8px;
    opacity: 0.6;
  }

  .faq {
    margin-top: 64px;
    padding-top: 8px;
  }

  .faq-item {
    padding: 22px 0;
    border-bottom: 1px solid var(--rule);
  }

  .faq-item h2 {
    font-family: 'Fraunces', serif;
    font-weight: 500;
    font-size: 19px;
    color: var(--text-on-ink);
    margin-bottom: 10px;
    max-width: 640px;
  }

  .faq-item p {
    font-size: 14.5px;
    color: var(--text-dim);
    line-height: 1.6;
    max-width: 640px;
  }

  footer {
    margin-top: 56px;
    text-align: center;
    color: var(--text-dim);
    font-family: 'IBM Plex Mono', monospace;
    font-size: 12px;
  }

  @media (prefers-reduced-motion: reduce) {
    .stamp.show, .bar-fill { animation: none; transition: none; }
  }

/* --- Site-wide navigation --- */
.site-nav {
  max-width: 1080px;
  margin: 0 auto 40px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--rule);
}

.site-nav .brand {
  font-family: 'Fraunces', serif;
  font-weight: 500;
  font-size: 18px;
  color: var(--text-on-ink);
  text-decoration: none;
}

.site-nav .brand em {
  font-style: italic;
  color: var(--brass-bright);
}

.site-nav .links {
  display: flex;
  gap: 28px;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12.5px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.site-nav .links a {
  color: var(--text-dim);
  text-decoration: none;
  transition: color 0.15s ease;
}

.site-nav .links a:hover,
.site-nav .links a.active {
  color: var(--brass-bright);
}

@media (max-width: 640px) {
  .site-nav { flex-direction: column; align-items: flex-start; gap: 14px; }
  .site-nav .links { gap: 18px; flex-wrap: wrap; }
}

/* --- Simple content pages (About, Contact, Privacy, Articles) --- */
.page-wrap {
  max-width: 720px;
  margin: 0 auto;
}

.page-wrap h1 {
  font-family: 'Fraunces', serif;
  font-weight: 500;
  font-size: clamp(28px, 4.5vw, 42px);
  line-height: 1.1;
  color: var(--text-on-ink);
  margin-bottom: 20px;
}

.page-wrap .page-sub {
  color: var(--text-dim);
  font-size: 15px;
  margin-bottom: 40px;
  line-height: 1.6;
}

.page-wrap h2 {
  font-family: 'Fraunces', serif;
  font-weight: 500;
  font-size: 22px;
  color: var(--text-on-ink);
  margin: 36px 0 14px;
}

.page-wrap h3 {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 13px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--brass-bright);
  margin: 28px 0 10px;
}

.page-wrap p {
  color: var(--text-on-ink);
  font-size: 15.5px;
  line-height: 1.7;
  margin-bottom: 16px;
}

.page-wrap ul, .page-wrap ol {
  color: var(--text-on-ink);
  font-size: 15.5px;
  line-height: 1.7;
  margin: 0 0 20px 22px;
}

.page-wrap li {
  margin-bottom: 8px;
}

.page-wrap a {
  color: var(--brass-bright);
}

.page-wrap strong {
  color: var(--brass-bright);
  font-weight: 600;
}

.byline {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  color: var(--text-dim);
  margin-bottom: 36px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--rule);
}

/* --- Contact form --- */
.contact-form {
  display: flex;
  flex-direction: column;
  gap: 20px;
  max-width: 480px;
  margin-top: 24px;
}

.form-field label {
  display: block;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--brass);
  margin-bottom: 8px;
}

.form-field input,
.form-field textarea {
  width: 100%;
  background: transparent;
  border: none;
  border-bottom: 1px solid var(--rule);
  color: var(--text-on-ink);
  font-family: 'IBM Plex Sans', sans-serif;
  font-size: 15px;
  padding: 8px 2px;
  transition: border-color 0.15s ease;
}

.form-field input:focus,
.form-field textarea:focus {
  outline: none;
  border-bottom: 1px solid var(--brass);
}

.form-field textarea {
  min-height: 120px;
  resize: vertical;
}

.contact-form .calc-btn {
  width: auto;
  padding: 14px 28px;
  align-self: flex-start;
}

/* --- Guides hub / article cards --- */
.guide-list {
  display: flex;
  flex-direction: column;
  gap: 0;
  margin-top: 8px;
}

.guide-card {
  display: block;
  padding: 22px 0;
  border-bottom: 1px solid var(--rule);
  text-decoration: none;
  transition: padding-left 0.15s ease;
}

.guide-card:hover {
  padding-left: 8px;
}

.guide-card .guide-eyebrow {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--brass);
  margin-bottom: 8px;
}

.guide-card h3 {
  font-family: 'Fraunces', serif;
  font-weight: 500;
  font-size: 21px;
  color: var(--text-on-ink);
  margin: 0 0 8px;
  text-transform: none;
  letter-spacing: normal;
}

.guide-card p {
  color: var(--text-dim);
  font-size: 14.5px;
  line-height: 1.55;
  margin: 0;
}

/* --- Article footer callout --- */
.callout {
  background: var(--paper);
  color: var(--ink-deep);
  padding: 28px 32px;
  margin: 40px 0;
}

.callout h3 {
  font-family: 'Fraunces', serif;
  font-weight: 500;
  font-size: 20px;
  color: var(--ink-deep);
  text-transform: none;
  letter-spacing: normal;
  margin: 0 0 10px;
}

.callout p {
  color: #4A5460;
  margin-bottom: 16px;
}

.callout a.cta {
  display: inline-block;
  background: var(--brass);
  color: var(--ink-deep);
  padding: 10px 22px;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12.5px;
  font-weight: 600;
  text-decoration: none;
  letter-spacing: 0.04em;
}

/* --- Footer links --- */
.footer-links {
  margin-top: 8px;
  display: flex;
  justify-content: center;
  gap: 18px;
}

.footer-links a {
  color: var(--text-dim);
  text-decoration: none;
}

.footer-links a:hover {
  color: var(--brass-bright);
}

/* --- Simple tool calculators (lighter than the invoice-style main calculator) --- */
.tool-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: start;
}

@media (max-width: 860px) {
  .tool-grid { grid-template-columns: 1fr; }
}

.result-card {
  background: var(--paper);
  color: var(--ink-deep);
  padding: 32px 30px;
  position: sticky;
  top: 40px;
}

.result-card .result-label {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: #6B7580;
  margin-bottom: 8px;
}

.result-card .result-number {
  font-family: 'Fraunces', serif;
  font-size: 42px;
  font-weight: 500;
  color: var(--ink-deep);
  line-height: 1.1;
  margin-bottom: 4px;
}

.result-card .result-sub {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12.5px;
  color: #6B7580;
  margin-bottom: 20px;
}

.result-card .result-breakdown {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 13px;
  border-top: 1px solid #C7C1AF;
  padding-top: 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.result-card .result-row {
  display: flex;
  justify-content: space-between;
  color: #4A5460;
}

.result-card .result-row.total {
  color: var(--ink-deep);
  font-weight: 600;
  border-top: 1px dashed #C7C1AF;
  padding-top: 8px;
  margin-top: 2px;
}

.result-card .result-note {
  margin-top: 18px;
  font-size: 12.5px;
  color: #6B7580;
  line-height: 1.5;
}

.tool-section-label {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--brass);
  margin-bottom: 20px;
}

.tool-divider {
  margin: 48px 0;
  border: none;
  border-top: 1px solid var(--rule);
}

/* --- Toggle buttons (for tools with two modes) --- */
.toggle-row {
  display: flex;
  gap: 0;
  margin-bottom: 32px;
  border: 1px solid var(--rule);
}

.toggle-btn {
  flex: 1;
  padding: 12px;
  background: transparent;
  border: none;
  color: var(--text-dim);
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12.5px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease;
}

.toggle-btn.active {
  background: var(--brass);
  color: var(--ink-deep);
  font-weight: 600;
}