:root {
  --paper: #fbf7ef;
  --paper-deep: #f1e8d8;
  --ink: #251f18;
  --muted: #6b604f;
  --line: #d8c7ac;
  --olive: #6c7428;
  --olive-dark: #4d5418;
  --rust: #a24724;
  --rust-soft: #f7e7de;
  --cream: #fffdf8;
  --shadow: 0 20px 55px rgba(68, 51, 27, 0.12);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background:
    radial-gradient(circle at top left, rgba(162, 71, 36, 0.12), transparent 32rem),
    linear-gradient(135deg, #fffaf1 0%, var(--paper) 46%, #efe0c9 calc(50% + 50%));
  color: var(--ink);
  font-family: "Aptos", "Segoe UI", sans-serif;
  line-height: 1.55;
  overflow-x: hidden;
}

main {
  width: min(1180px, calc(100vw - 32px));
  margin: 0 auto;
  padding: 28px 0 52px;
}

h1,
h2,
h3,
.result-card strong {
  font-family: Georgia, "Times New Roman", serif;
}

h1 {
  margin: 0;
  font-size: clamp(3rem, 8vw, 5.8rem);
  line-height: 0.9;
  letter-spacing: -0.06em;
}

h2 {
  margin: 0 0 14px;
  font-size: clamp(1.35rem, 2.4vw, 2rem);
}

p {
  margin: 0 0 14px;
}

button,
input {
  font: inherit;
}

.hero {
  padding: 28px 4px 18px;
}

.hero__intro {
  max-width: 920px;
}

.eyebrow {
  margin-bottom: 8px;
  color: var(--olive-dark);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.lede {
  max-width: 880px;
  margin-top: 16px;
  color: var(--muted);
  font-size: 1.12rem;
}

.notice {
  display: inline-flex;
  max-width: 920px;
  margin-top: 4px;
  padding: 10px 14px;
  border: 1px solid rgba(108, 116, 40, 0.3);
  border-radius: 999px;
  background: rgba(255, 253, 248, 0.7);
  color: var(--olive-dark);
  font-size: 0.95rem;
}

.calculator-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 16px;
  align-items: start;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: rgba(255, 253, 248, 0.78);
  box-shadow: var(--shadow);
  max-width: calc(50% + 50%);
}

.panel {
  border: 1px solid var(--line);
  border-radius: 16px;
  background: rgba(255, 253, 248, 0.82);
}

.panel--form {
  padding: 18px;
}

.panel--assumptions {
  padding: 18px;
}

.panel--assumptions ul,
.content-card ul,
.content-card ol {
  padding-left: 20px;
  margin: 0;
}

.panel--assumptions li,
.content-card li {
  margin-bottom: 8px;
}

.panel--results {
  grid-column: 1 / -1;
  padding: 18px;
}

.step-heading {
  display: flex;
  gap: 10px;
  align-items: center;
  margin-bottom: 16px;
}

.step-heading span {
  display: grid;
  width: 34px;
  height: 34px;
  place-items: center;
  border-radius: 50%;
  background: var(--olive);
  color: var(--cream);
  font-weight: 800;
}

.step-heading h2 {
  margin: 0;
}

.mode-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
  margin-bottom: 18px;
}

.mode-card {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  min-height: 92px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.42);
  cursor: pointer;
  min-width: 0;
}

.mode-card:has(input:checked) {
  border-color: var(--olive);
  background: linear-gradient(135deg, rgba(108, 116, 40, 0.13), rgba(255, 253, 248, 0.7));
  box-shadow: inset 0 0 0 1px rgba(108, 116, 40, 0.28);
}

.mode-card input {
  margin-top: 4px;
  accent-color: var(--olive);
}

.mode-card strong,
.mode-card small {
  display: block;
}

.mode-card small,
label small {
  color: var(--muted);
}

.input-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 12px;
}

label span {
  display: block;
  margin-bottom: 6px;
  font-weight: 800;
}

input[type="number"] {
  width: calc(50% + 50%);
  min-height: 48px;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--cream);
  color: var(--ink);
  min-width: 0;
}

input:disabled {
  background: #eee5d5;
  color: #746850;
}

.form-message {
  min-height: 26px;
  margin: 12px 0;
  color: var(--muted);
}

.form-message[data-state="error"] {
  color: #8a2f1d;
  font-weight: 800;
}

.actions {
  display: grid;
  grid-template-columns: 1.2fr 1fr 1fr 0.75fr;
  gap: 12px;
  border-top: 1px solid var(--line);
  padding-top: 14px;
}

.button {
  min-height: 48px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--cream);
  color: var(--ink);
  font-weight: 800;
  cursor: pointer;
}

.button--primary {
  border-color: var(--olive);
  background: linear-gradient(135deg, var(--olive), var(--olive-dark));
  color: var(--cream);
}

.button--ghost {
  background: transparent;
}

.button:focus-visible,
input:focus-visible,
summary:focus-visible {
  outline: 3px solid rgba(162, 71, 36, 0.35);
  outline-offset: 2px;
}

.results-heading {
  display: flex;
  gap: 18px;
  align-items: end;
  justify-content: space-between;
  margin-bottom: 16px;
}

.results-heading h2 {
  margin-bottom: 0;
}

#result-summary {
  max-width: 480px;
  color: var(--muted);
  text-align: right;
}

.result-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 12px;
}

.result-card {
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: linear-gradient(180deg, #fffdf8, #f8f0e2);
  text-align: center;
  min-width: 0;
}

.result-card span,
.result-card small {
  display: block;
}

.result-card span {
  color: var(--olive-dark);
  font-weight: 900;
}

.result-card strong {
  display: block;
  margin: 8px 0 4px;
  color: var(--olive-dark);
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1;
  overflow-wrap: anywhere;
}

.result-card--rust span,
.result-card--rust strong {
  color: var(--rust);
}

.formula-strip,
.examples,
.privacy-note,
.content-card {
  margin-top: 16px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(255, 253, 248, 0.78);
}

.formula-strip,
.examples,
.privacy-note {
  padding: 22px;
}

.formula-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--line);
}

.formula-grid p {
  margin: 0;
  padding: 16px;
  background: var(--cream);
  text-align: center;
}

.formula-grid strong,
.formula-grid span {
  display: block;
}

.formula-grid span {
  margin-top: 6px;
  color: var(--muted);
}

.content-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-top: 16px;
}

.content-card {
  padding: 22px;
}

.content-card--review {
  background: linear-gradient(135deg, rgba(108, 116, 40, 0.12), rgba(255, 253, 248, 0.9));
}

.section-heading {
  max-width: 760px;
  margin-bottom: 16px;
}

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

table {
  width: calc(50% + 50%);
  border-collapse: collapse;
  min-width: 760px;
}

th,
td {
  padding: 14px;
  border: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

th {
  background: var(--paper-deep);
  color: var(--olive-dark);
}

.faq {
  margin-top: 16px;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(255, 253, 248, 0.78);
}

.faq-list {
  display: grid;
  gap: 10px;
}

details {
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--cream);
}

summary {
  padding: 14px 16px;
  font-weight: 900;
  cursor: pointer;
}

details p {
  padding: 0 16px 16px;
}

.privacy-note {
  background: linear-gradient(135deg, var(--paper-deep), rgba(255, 253, 248, 0.88));
}

@media (max-width: 980px) {
  .calculator-shell,
  .content-grid {
    grid-template-columns: 1fr;
  }

  .mode-grid,
  .input-grid,
  .result-grid,
  .formula-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .panel--assumptions {
    order: 4;
  }
}

@media (max-width: 640px) {
  html {
    overflow-x: hidden;
  }

  main {
    width: min(calc(100vw - 20px), 1180px);
    padding-top: 18px;
  }

  h1 {
    font-size: clamp(2.65rem, 17vw, 4rem);
    overflow-wrap: anywhere;
  }

  .lede,
  .notice,
  .content-card,
  .panel,
  .formula-strip,
  .examples,
  .faq,
  .privacy-note {
    overflow-wrap: anywhere;
  }

  .notice {
    border-radius: 16px;
  }

  .calculator-shell,
  .panel--form,
  .panel--results,
  .formula-strip,
  .examples,
  .faq,
  .privacy-note,
  .content-card {
    padding: 14px;
    border-radius: 14px;
  }

  .mode-grid,
  .input-grid,
  .result-grid,
  .formula-grid,
  .actions {
    grid-template-columns: 1fr;
  }

  .results-heading {
    display: block;
  }

  #result-summary {
    text-align: left;
  }
}