:root {
  --paper: #f3ecdc;
  --paper-2: #faf6ec;
  --ink: #1c1914;
  --muted: #5e574c;
  --forest: #243d2e;
  --forest-2: #1a2c22;
  --moss: #3d5a45;
  --rust: #8b3d1b;
  --rust-2: #6e2f14;
  --rule: #cfc6b3;
  --box: #e8dfcc;
  --good: #1f4d38;
  --owe: #7a2e14;
  --warn: #6b4e16;
  --warn-bg: #f3e3b8;
  --mono: "IBM Plex Mono", ui-monospace, "Liberation Mono", monospace;
  --sans: "IBM Plex Sans", "Liberation Sans", "Segoe UI", sans-serif;
  --serif: "Source Serif 4", "Liberation Serif", "Times New Roman", serif;
  --shadow: 0 18px 40px rgba(28, 25, 20, 0.08);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background:
    radial-gradient(1200px 500px at 10% -10%, #e7efe6 0%, transparent 50%),
    var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16.5px;
  line-height: 1.55;
}

a { color: var(--forest); }
a:hover { color: var(--rust); }

.wrap { width: min(1120px, calc(100% - 32px)); margin: 0 auto; }

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 0 10px;
  border-bottom: 1px solid var(--rule);
}
.brand {
  display: flex;
  align-items: baseline;
  gap: 10px;
  text-decoration: none;
  color: inherit;
}
.brand-mark {
  font-family: var(--serif);
  font-weight: 700;
  letter-spacing: -0.02em;
  font-size: 1.15rem;
}
.brand-mark span { color: var(--rust); }
.brand-sub {
  font-family: var(--mono);
  font-size: 0.68rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}
.topnav { display: flex; gap: 18px; align-items: center; }
.topnav a {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--muted);
}
.topnav a:hover { color: var(--ink); }

.hero {
  display: grid;
  grid-template-columns: 0.92fr 1.08fr;
  gap: 36px;
  padding: 36px 0 20px;
  align-items: start;
}
@media (max-width: 900px) {
  .hero { grid-template-columns: 1fr; padding-top: 22px; }
}

.kicker {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--moss);
  margin: 0 0 10px;
}
h1 {
  font-family: var(--serif);
  font-weight: 700;
  font-size: clamp(2rem, 4vw, 3.05rem);
  line-height: 1.08;
  letter-spacing: -0.025em;
  margin: 0 0 14px;
}
.lede {
  margin: 0 0 16px;
  color: var(--muted);
  font-size: 1.05rem;
  max-width: 38ch;
}
.lede strong { color: var(--ink); font-weight: 600; }

.points { list-style: none; padding: 0; margin: 0 0 18px; }
.points li {
  position: relative;
  padding-left: 18px;
  margin: 0 0 8px;
  color: var(--ink);
  font-size: 0.95rem;
}
.points li::before {
  content: "";
  position: absolute;
  left: 0; top: 0.55em;
  width: 8px; height: 1.5px;
  background: var(--rust);
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 18px;
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--muted);
  letter-spacing: 0.04em;
}

.sheet {
  background: var(--paper-2);
  border: 1px solid var(--rule);
  box-shadow: var(--shadow);
  padding: 18px 18px 16px;
}
.sheet-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  border-bottom: 1px solid var(--rule);
  padding-bottom: 10px;
  margin-bottom: 14px;
}
.sheet-head h2 {
  font-family: var(--serif);
  font-size: 1.15rem;
  margin: 0;
  letter-spacing: -0.02em;
}
.mode-toggle {
  display: inline-flex;
  border: 1px solid var(--rule);
  background: var(--box);
}
.mode-toggle button {
  appearance: none;
  border: 0;
  background: transparent;
  font-family: var(--mono);
  font-size: 0.68rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 6px 10px;
  cursor: pointer;
  color: var(--muted);
}
.mode-toggle button[aria-pressed="true"] {
  background: var(--forest);
  color: #f3ead8;
}

form.calc { display: grid; gap: 10px; }
.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}
@media (max-width: 560px) { .grid-2 { grid-template-columns: 1fr; } }

label.field {
  display: flex;
  flex-direction: column;
  gap: 4px;
  font-size: 0.78rem;
  color: var(--muted);
}
label.field span.lbl {
  font-family: var(--mono);
  letter-spacing: 0.04em;
  text-transform: uppercase;
  font-size: 0.68rem;
}
label.field input, label.field select {
  font-family: var(--mono);
  font-size: 0.95rem;
  padding: 8px 10px;
  border: 1px solid var(--rule);
  background: #fffdf7;
  color: var(--ink);
  outline: none;
}
label.field input:focus {
  border-color: var(--forest);
  box-shadow: 0 0 0 3px rgba(36, 61, 46, 0.12);
}
.adv-only { display: none; }
.sheet[data-mode="advanced"] .adv-only { display: grid; }
.sheet[data-mode="advanced"] .simple-only { display: none; }

.mode-note {
  font-size: 0.8rem;
  color: var(--muted);
  background: var(--box);
  padding: 8px 10px;
  margin: 2px 0 6px;
}

.preview {
  margin-top: 12px;
  border-top: 1px dashed var(--rule);
  padding-top: 12px;
}
.preview h3 {
  margin: 0 0 8px;
  font-family: var(--serif);
  font-size: 1rem;
}
.rows { width: 100%; border-collapse: collapse; }
.rows th, .rows td {
  text-align: left;
  padding: 6px 4px;
  border-bottom: 1px solid var(--rule);
  font-size: 0.86rem;
  vertical-align: top;
}
.rows td.amt {
  font-family: var(--mono);
  text-align: right;
  white-space: nowrap;
  width: 28%;
}
.rows .note { color: var(--muted); font-size: 0.75rem; display: block; }
.verdict {
  margin-top: 12px;
  padding: 12px 12px 10px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  border: 1.5px solid var(--forest);
  background: #e7eee6;
}
.verdict.owe { border-color: var(--owe); background: #f6e8e1; }
.verdict .dir {
  font-family: var(--serif);
  font-weight: 700;
  font-size: 1.05rem;
}
.verdict .dollars {
  font-family: var(--mono);
  font-size: 1.25rem;
  font-weight: 500;
}
.err {
  color: var(--owe);
  font-size: 0.85rem;
  min-height: 1.2em;
}

.actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
button.primary, a.primary {
  appearance: none;
  border: 0;
  background: var(--rust);
  color: #fff8ef;
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 11px 14px;
  cursor: pointer;
  text-decoration: none;
  display: inline-block;
}
button.primary:hover, a.primary:hover { background: var(--rust-2); }
button.ghost, a.ghost {
  appearance: none;
  border: 1px solid var(--forest);
  background: transparent;
  color: var(--forest);
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 10px 12px;
  cursor: pointer;
  text-decoration: none;
  display: inline-block;
}
button.ghost:hover, a.ghost:hover { background: var(--forest); color: #f3ead8; }
button:disabled { opacity: 0.5; cursor: not-allowed; }

.devbanner {
  display: none;
  margin-top: 10px;
  background: var(--warn-bg);
  color: var(--warn);
  border: 1px dashed #b08a2b;
  padding: 8px 10px;
  font-size: 0.8rem;
}
.devbanner.show { display: block; }

section.block { padding: 42px 0 10px; }
section.block h2 {
  font-family: var(--serif);
  font-size: 1.7rem;
  letter-spacing: -0.02em;
  margin: 0 0 8px;
}
.rule { height: 1px; background: var(--rule); margin: 8px 0 18px; }

.faq { display: grid; gap: 0; border-top: 1px solid var(--rule); }
.faq details {
  border-bottom: 1px solid var(--rule);
  padding: 12px 0;
}
.faq summary {
  cursor: pointer;
  font-family: var(--serif);
  font-size: 1.05rem;
  font-weight: 600;
  list-style: none;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+";
  float: right;
  font-family: var(--mono);
  color: var(--muted);
}
.faq details[open] summary::after { content: "–"; }
.faq p { color: var(--muted); margin: 8px 0 0; max-width: 72ch; }

.disclaimer, footer.site {
  color: var(--muted);
  font-size: 0.82rem;
}
.disclaimer {
  background: var(--box);
  padding: 16px 18px;
  margin: 28px 0 10px;
}
footer.site {
  padding: 22px 0 40px;
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  border-top: 1px solid var(--rule);
  margin-top: 10px;
}

.success {
  max-width: 640px;
  margin: 48px auto 80px;
  background: var(--paper-2);
  border: 1px solid var(--rule);
  padding: 28px;
  box-shadow: var(--shadow);
}
.success h1 { font-size: 2rem; }