:root {
  --ink: #173b37;
  --muted: #5b6b65;
  --paper: #f7f6f0;
  --line: #d9e0d6;
  --green: #24594c;
  --light: #edf2e8;
  --gold: #e9ca7f;
  --white: #fff;
  --red: #9b3225;
  font-family:
    Inter,
    ui-sans-serif,
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    sans-serif;
  color: var(--ink);
  background: var(--paper);
  font-synthesis: none;
}
* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
  scroll-padding-top: 2rem;
}
body {
  margin: 0;
}
a {
  color: inherit;
}
button,
input,
select,
textarea {
  font: inherit;
}
button,
a,
input,
select,
summary,
textarea {
  outline-offset: 5px;
}
button {
  cursor: pointer;
}
a {
  text-underline-offset: 4px;
}
.site-header {
  max-width: 1320px;
  margin: auto;
  padding: 28px 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
}
.brand {
  font-size: 18px;
  font-weight: 700;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 10px;
  letter-spacing: -0.5px;
}
.brand-mark {
  background: var(--ink);
  color: var(--gold);
  border-radius: 8px;
  width: 32px;
  height: 32px;
  display: grid;
  place-items: center;
  font:
    italic 27px Georgia,
    serif;
}
nav {
  display: flex;
  gap: 28px;
  font-size: 13px;
  font-weight: 600;
}
nav a {
  text-decoration: none;
}
nav a:hover {
  text-decoration: underline;
}
main {
  max-width: 1224px;
  margin: auto;
  padding: 0 24px;
}
.hero {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 90px;
  padding: 84px 0 80px;
  align-items: center;
}
.eyebrow {
  font-size: 11px;
  letter-spacing: 2px;
  font-weight: 750;
  margin: 0 0 20px;
  color: var(--green);
}
h1 {
  font-size: clamp(40px, 5.6vw, 72px);
  line-height: 1.07;
  letter-spacing: -3px;
  font-weight: 550;
  margin: 0 0 24px;
}
h1 em {
  font-family: Georgia, serif;
  font-weight: 400;
}
h2 {
  font-size: 31px;
  letter-spacing: -1px;
  font-weight: 550;
  margin: 0;
}
h3 {
  font-size: 18px;
  letter-spacing: -0.4px;
  margin: 0 0 12px;
}
.intro {
  font-size: 17px;
  line-height: 1.65;
  color: var(--muted);
  max-width: 500px;
  margin: 0 0 28px;
}
.button {
  display: inline-flex;
  justify-content: center;
  align-items: center;
  gap: 24px;
  border: 1px solid transparent;
  border-radius: 7px;
  padding: 13px 20px;
  font-size: 13px;
  font-weight: 650;
  text-decoration: none;
  min-height: 44px;
}
.primary {
  background: var(--ink);
  color: white;
}
.primary:hover {
  background: #24594c;
}
.subtle {
  background: transparent;
  border-color: var(--line);
  color: var(--ink);
}
.subtle:hover {
  background: var(--light);
}
button:disabled {
  opacity: 0.55;
  cursor: wait;
}
.small {
  font-size: 12px;
  line-height: 1.6;
  color: var(--muted);
}
.caps {
  letter-spacing: 1.5px;
  font-weight: 600;
  font-size: 10px;
}
.principle {
  background: var(--light);
  border: 1px solid #d5dfcf;
  border-radius: 12px;
  padding: 32px;
  position: relative;
}
.principle-title {
  font-family: Georgia, serif;
  font-size: 42px;
  line-height: 1.15;
  letter-spacing: -1px;
  margin: 24px 0;
}
.principle > p:last-of-type {
  font-size: 14px;
  line-height: 1.7;
}
.flow {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 10px;
  margin: 22px 0;
}
.flow span:nth-child(odd) {
  padding: 9px 10px;
  border: 1px solid #bdcdb6;
  border-radius: 5px;
  background: #f5f8f1;
}
.badge {
  display: inline-block;
  font-size: 10px;
  border-top: 1px solid #cad8c2;
  padding-top: 16px;
  margin-top: 8px;
  letter-spacing: 0.2px;
}
.workspace {
  padding: 48px 0 60px;
  border-top: 1px solid var(--line);
}
.section-heading {
  display: flex;
  justify-content: space-between;
  align-items: end;
  gap: 20px;
  margin-bottom: 24px;
}
.section-heading .eyebrow {
  margin-bottom: 10px;
}
.notice {
  padding: 14px 18px;
  background: #efe8d6;
  color: #625638;
  border-radius: 7px;
  font-size: 12px;
  line-height: 1.6;
  margin-bottom: 24px;
}
.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}
.panel {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 26px;
  margin-bottom: 20px;
}
.panel-heading {
  display: flex;
  align-items: start;
  gap: 12px;
  margin-bottom: 20px;
}
.panel-heading h3 {
  margin: 4px 0 0;
}
.step {
  display: grid;
  place-items: center;
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  border: 1px solid var(--line);
  border-radius: 50%;
  font-size: 11px;
  font-weight: 650;
  color: var(--muted);
}
.fields {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px 18px;
}
.fields label {
  font-size: 12px;
  font-weight: 600;
  display: flex;
  flex-direction: column;
  gap: 8px;
  line-height: 1.4;
}
.cash-fields {
  display: contents;
}
.hint {
  display: block;
  font-size: 11px;
  line-height: 1.5;
  color: var(--muted);
  font-weight: 400;
}
input,
select,
textarea {
  width: 100%;
  min-width: 0;
  border: 1px solid #c9d4c8;
  border-radius: 5px;
  padding: 10px 12px;
  background: #fff;
  color: var(--ink);
  min-height: 42px;
}
input:hover,
select:hover,
textarea:hover {
  border-color: var(--green);
}
input:focus,
select:focus,
textarea:focus {
  outline: 2px solid var(--green);
  outline-offset: 2px;
}
table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 13px;
}
th,
td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--line);
  font-variant-numeric: tabular-nums;
}
th {
  font-weight: 600;
}
thead th {
  font-size: 11px;
  color: var(--muted);
  padding-top: 0;
}
tbody tr:last-child th,
tbody tr:last-child td {
  border-bottom: 0;
}
.base-row {
  background: #f5f8f2;
}
.scenarios input {
  max-width: 160px;
}
.table-scroll {
  overflow-x: auto;
}
.advanced {
  margin-top: 20px;
  border-top: 1px solid var(--line);
  padding-top: 18px;
}
summary {
  cursor: pointer;
  font-size: 13px;
  font-weight: 650;
  padding: 4px 0;
}
details .fields {
  margin-top: 18px;
}
.form-actions {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
  margin: 8px 0 32px;
}
.error {
  color: var(--red);
  background: #fff1ed;
  border: 1px solid #e9bfb5;
  border-radius: 7px;
  padding: 14px;
  font-size: 13px;
}
#results {
  padding-top: 30px;
  border-top: 1px solid var(--line);
}
.actions {
  display: flex;
  gap: 8px;
}
.result-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-bottom: 20px;
}
.result-card {
  background: white;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 24px;
}
.result-card.base {
  border: 2px solid var(--green);
  padding: 23px;
}
.result-card h3 {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 1.5px;
}
.result-number {
  font-size: 32px;
  letter-spacing: -1px;
  font-weight: 550;
  margin: 14px 0 4px;
  font-variant-numeric: tabular-nums;
}
.negative {
  color: var(--red);
}
.result-label {
  font-size: 11px;
  color: var(--muted);
  margin: 0 0 20px;
}
.result-detail {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  font-size: 12px;
  padding: 10px 0;
  border-top: 1px solid var(--line);
}
.result-detail span:first-child {
  color: var(--muted);
}
.result-detail strong {
  text-align: right;
}
.review-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}
li {
  font-size: 13px;
  line-height: 1.7;
  margin-bottom: 7px;
}
ul,
ol {
  padding-left: 20px;
}
.learn {
  padding: 58px 0 80px;
  border-top: 1px solid var(--line);
}
.learn-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}
.learn-grid article {
  padding: 24px 0;
  border-top: 1px solid var(--line);
}
.lesson-number {
  display: block;
  font-size: 10px;
  letter-spacing: 1.4px;
  color: var(--muted);
  margin-bottom: 20px;
}
.learn h3 {
  font:
    25px/1.2 Georgia,
    serif;
  letter-spacing: -0.4px;
}
.learn article p {
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
}
footer {
  max-width: 1272px;
  margin: auto;
  padding: 30px 24px;
  border-top: 1px solid var(--line);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 25px;
}
footer .brand {
  font-size: 15px;
}
footer p {
  font-size: 11px;
  color: var(--muted);
}
footer nav {
  gap: 20px;
  font-size: 11px;
}
.document {
  max-width: 760px;
  padding: 64px 24px 90px;
}
.document h1 {
  font-size: 46px;
  margin-bottom: 32px;
}
.document h2 {
  font-size: 23px;
  margin-top: 32px;
}
.document p,
.document li {
  font-size: 15px;
  line-height: 1.8;
}
.document .eyebrow {
  font-size: 11px;
}
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}
[hidden] {
  display: none !important;
}
@media (max-width: 850px) {
  .site-header {
    padding: 22px 24px;
  }
  .hero {
    gap: 32px;
    padding: 54px 0;
  }
  .principle {
    padding: 24px;
  }
  .flow {
    gap: 5px;
  }
  .flow span:nth-child(odd) {
    padding: 7px;
  }
  .form-grid {
    grid-template-columns: 1fr;
  }
  .result-grid {
    gap: 10px;
  }
  .result-card {
    padding: 18px;
  }
  .result-card.base {
    padding: 17px;
  }
  .result-number {
    font-size: 27px;
  }
  footer {
    flex-wrap: wrap;
  }
  .site-header nav {
    gap: 14px;
  }
  .learn-grid {
    gap: 18px;
  }
}
@media (max-width: 600px) {
  main {
    padding: 0 18px;
  }
  .site-header {
    padding: 18px;
  }
  .brand {
    font-size: 16px;
  }
  .site-header nav a:not(:last-child) {
    display: none;
  }
  .hero {
    grid-template-columns: 1fr;
    padding: 44px 0;
    gap: 32px;
  }
  h1 {
    letter-spacing: -2px;
    font-size: 49px;
  }
  .principle-title {
    font-size: 33px;
  }
  .principle {
    padding: 24px;
  }
  .workspace {
    padding-top: 32px;
  }
  .section-heading {
    align-items: start;
  }
  h2 {
    font-size: 26px;
  }
  .section-heading .button {
    font-size: 11px;
    padding: 10px;
  }
  .panel {
    padding: 20px 16px;
  }
  .fields {
    gap: 18px 12px;
  }
  .form-actions {
    align-items: stretch;
    flex-direction: column;
  }
  .result-grid {
    grid-template-columns: 1fr;
  }
  .result-card {
    padding: 24px;
  }
  .result-card.base {
    padding: 23px;
  }
  .result-number {
    font-size: 36px;
  }
  #results > .section-heading {
    flex-direction: column;
  }
  .review-grid,
  .learn-grid {
    grid-template-columns: 1fr;
  }
  .learn-grid {
    gap: 8px;
  }
  th,
  td {
    padding: 10px 8px;
    min-width: 90px;
  }
  .learn {
    padding-top: 36px;
  }
  .learn > .section-heading {
    flex-direction: column;
  }
  .scenarios table {
    min-width: 450px;
  }
  footer {
    padding: 24px 18px;
    gap: 16px;
  }
  footer p {
    width: 100%;
    margin: 0;
  }
  footer nav {
    gap: 24px;
  }
  .document h1 {
    font-size: 36px;
    letter-spacing: -1px;
  }
}
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}
@media print {
  .site-header,
  form,
  .hero,
  .learn,
  footer,
  .actions,
  #example-notice {
    display: none;
  }
  body {
    background: white;
  }
  .workspace {
    padding: 0;
    border: 0;
  }
  #results {
    border: 0;
  }
  .panel,
  .result-card {
    break-inside: avoid;
  }
  .result-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}
video {
  display: block;
  max-width: 100%;
  height: auto;
  border-radius: 8px;
  background: var(--ink);
}