:root {
  color-scheme: light;
  --canvas: #f7f8f4;
  --surface: #ffffff;
  --surface-soft: #eff4ee;
  --ink: #18211d;
  --ink-muted: #59635e;
  --ink-faint: #7c867f;
  --line: #d9e1da;
  --line-strong: #bdc9bf;
  --brand: #166b52;
  --brand-dark: #0e4e3c;
  --brand-soft: #dff3e7;
  --accent: #e79552;
  --danger: #a93434;
  --danger-soft: #fceaea;
  --shadow: 0 18px 42px rgba(25, 40, 31, 0.08);
  --shell: min(1120px, calc(100% - 40px));
  --radius-lg: 22px;
  --radius-md: 14px;
  --radius-sm: 10px;
  --ease: 180ms cubic-bezier(0.2, 0.8, 0.2, 1);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-synthesis: none;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  min-width: 320px;
  background: var(--canvas);
  color: var(--ink);
  font-size: 16px;
  line-height: 1.5;
}

button, input, select { font: inherit; }

button, a, input, select { -webkit-tap-highlight-color: transparent; }

a { color: inherit; text-decoration: none; }

a:focus-visible, button:focus-visible, input:focus-visible, select:focus-visible, summary:focus-visible {
  outline: 3px solid #0e78d1;
  outline-offset: 3px;
}

.shell { width: var(--shell); margin-inline: auto; }

.skip-link {
  position: fixed;
  z-index: 50;
  top: 12px;
  left: 12px;
  padding: 10px 14px;
  border-radius: 8px;
  background: var(--ink);
  color: #fff;
  transform: translateY(-140%);
  transition: transform var(--ease);
}

.skip-link:focus { transform: translateY(0); }

.site-header {
  border-bottom: 1px solid rgba(217, 225, 218, 0.82);
  background: color-mix(in srgb, var(--canvas) 90%, transparent);
  backdrop-filter: blur(12px);
}

.header-inner, .footer-inner { display: flex; align-items: center; justify-content: space-between; gap: 24px; }

.header-inner { min-height: 74px; }

.brand { display: inline-flex; align-items: center; gap: 9px; font-size: 1.06rem; font-weight: 740; letter-spacing: -0.035em; }

.brand-mark {
  display: grid;
  width: 31px;
  height: 31px;
  place-items: center;
  border-radius: 9px;
  background: var(--brand);
  color: #fff;
}

.brand-mark svg { width: 19px; height: 19px; }

.primary-nav, .site-footer nav { display: flex; align-items: center; gap: 24px; color: var(--ink-muted); font-size: 0.92rem; }

.primary-nav a, .site-footer nav a { transition: color var(--ease); }
.primary-nav a:hover, .site-footer nav a:hover { color: var(--brand-dark); }

.hero { padding: clamp(56px, 10vw, 116px) 0 64px; }

.eyebrow {
  margin: 0 0 12px;
  color: var(--brand-dark);
  font-size: 0.74rem;
  font-weight: 760;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

h1, h2, h3, p { overflow-wrap: break-word; }

h1, h2, h3 { margin: 0; letter-spacing: -0.055em; line-height: 0.98; }

h1 { max-width: 720px; font-size: clamp(3.35rem, 9vw, 7.55rem); font-weight: 780; }
h1 em { color: var(--brand); font-family: Georgia, serif; font-weight: 500; }
h2 { font-size: clamp(2rem, 4.7vw, 3.7rem); font-weight: 750; }
h3 { font-size: 1.15rem; font-weight: 730; letter-spacing: -0.035em; }

.hero-intro { max-width: 560px; margin: 26px 0 0; color: var(--ink-muted); font-size: clamp(1.05rem, 1.65vw, 1.2rem); line-height: 1.65; }

.tool-search { max-width: 800px; margin-top: clamp(42px, 7vw, 68px); }
.tool-search > label { display: block; margin-bottom: 11px; font-weight: 680; letter-spacing: -0.02em; }

.search-control {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 7px 7px 7px 17px;
  border: 1px solid var(--line-strong);
  border-radius: 16px;
  background: var(--surface);
  box-shadow: 0 5px 14px rgba(24, 33, 29, 0.025);
  transition: border-color var(--ease), box-shadow var(--ease);
}

.search-control:focus-within { border-color: var(--brand); box-shadow: 0 0 0 4px rgba(22, 107, 82, 0.12); }
.search-control > svg { flex: 0 0 auto; width: 22px; height: 22px; color: var(--ink-faint); }
.search-control input { min-width: 0; flex: 1; height: 44px; border: 0; outline: 0; background: transparent; color: var(--ink); }
.search-control input::placeholder { color: var(--ink-faint); }

.button {
  min-height: 44px;
  padding: 10px 16px;
  border: 1px solid transparent;
  border-radius: 10px;
  cursor: pointer;
  font-weight: 700;
  letter-spacing: -0.02em;
  transition: background var(--ease), color var(--ease), border-color var(--ease), transform var(--ease), box-shadow var(--ease);
}

.button:active { transform: translateY(1px); }
.button.primary { background: var(--brand); color: #fff; }
.button.primary:hover { background: var(--brand-dark); box-shadow: 0 5px 12px rgba(14, 78, 60, 0.16); }
.button.secondary { border-color: var(--line-strong); background: transparent; color: var(--ink); }
.button.secondary:hover { border-color: var(--brand); color: var(--brand-dark); background: var(--brand-soft); }
.button.ghost { border-color: transparent; background: transparent; color: var(--brand-dark); }
.button.ghost:hover { background: var(--brand-soft); }

.search-status { min-height: 24px; margin: 9px 0 0; color: var(--ink-muted); font-size: 0.9rem; }

.popular-tools { display: flex; flex-wrap: wrap; align-items: center; gap: 9px 17px; margin-top: 28px; font-size: 0.91rem; }
.popular-label { color: var(--ink-faint); }
.popular-tools a { border-bottom: 1px solid transparent; color: var(--brand-dark); font-weight: 650; transition: border-color var(--ease); }
.popular-tools a:hover { border-color: currentColor; }

.tools-section { padding: clamp(64px, 9vw, 110px) 0; border-top: 1px solid var(--line); background: #fff; }
.section-heading { display: flex; align-items: flex-end; justify-content: space-between; gap: 32px; }

.filter-row { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 7px; }
.filter-button { min-height: 36px; padding: 7px 12px; border: 1px solid var(--line); border-radius: 999px; background: #fff; color: var(--ink-muted); cursor: pointer; font-size: 0.86rem; font-weight: 650; transition: color var(--ease), background var(--ease), border-color var(--ease); }
.filter-button:hover, .filter-button[aria-pressed="true"] { border-color: var(--brand); background: var(--brand-soft); color: var(--brand-dark); }

.tool-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 13px; margin-top: 38px; }
.tool-card { display: flex; min-height: 166px; flex-direction: column; justify-content: space-between; padding: 21px; border: 1px solid var(--line); border-radius: var(--radius-md); background: #fff; transition: border-color var(--ease), box-shadow var(--ease), transform var(--ease); }
.tool-card:hover { border-color: #9fb4a5; box-shadow: 0 12px 26px rgba(24, 43, 31, 0.09); transform: translateY(-2px); }
.tool-card-category { display: flex; align-items: center; justify-content: space-between; color: var(--ink-faint); font-size: 0.77rem; font-weight: 730; letter-spacing: 0.07em; text-transform: uppercase; }
.tool-card-arrow { width: 18px; height: 18px; color: var(--brand); }
.tool-card h3 { margin-top: 22px; }
.tool-card p { margin: 8px 0 0; color: var(--ink-muted); font-size: 0.91rem; line-height: 1.45; }
.empty-search { grid-column: 1 / -1; padding: 32px; border: 1px dashed var(--line-strong); border-radius: var(--radius-md); color: var(--ink-muted); text-align: center; }

.principles { display: grid; grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr); gap: clamp(36px, 9vw, 116px); padding: clamp(68px, 10vw, 128px) 0; }
.principles h2 { max-width: 480px; }
.principle-list { display: grid; gap: 0; margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--line); }
.principle-list li { display: grid; gap: 6px; padding: 22px 0; border-bottom: 1px solid var(--line); }
.principle-list strong { font-size: 1.02rem; letter-spacing: -0.02em; }
.principle-list span { color: var(--ink-muted); }

.site-footer { border-top: 1px solid var(--line); background: #f0f3ed; }
.footer-inner { min-height: 164px; }
.brand-footer { font-size: 1.13rem; }
.site-footer p { margin: 7px 0 0; color: var(--ink-muted); font-size: 0.9rem; }

.calculator-page { padding: 36px 0 clamp(72px, 10vw, 108px); }
.breadcrumb { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin-bottom: 34px; color: var(--ink-muted); font-size: 0.88rem; }
.breadcrumb a { color: var(--brand-dark); text-decoration: underline; text-decoration-color: transparent; text-underline-offset: 3px; transition: text-decoration-color var(--ease); }
.breadcrumb a:hover { text-decoration-color: currentColor; }
.breadcrumb-separator { color: var(--ink-faint); }

.calculator-header { max-width: 760px; margin-bottom: 35px; }
.calculator-header h1 { font-size: clamp(2.35rem, 5.8vw, 4.65rem); }
.calculator-header p:not(.eyebrow) { max-width: 630px; margin: 17px 0 0; color: var(--ink-muted); font-size: 1.08rem; line-height: 1.62; }

.static-calculator-copy { max-width: 760px; }
.static-calculator-copy h1 { font-size: clamp(2.35rem, 5.8vw, 4.65rem); }
.static-calculator-copy p:not(.eyebrow) { max-width: 650px; margin: 17px 0 0; color: var(--ink-muted); font-size: 1.04rem; line-height: 1.65; }
.static-calculator-copy h2 { margin-top: 28px; font-size: 1.35rem; }

.calculator-layout { display: grid; grid-template-columns: minmax(0, 0.93fr) minmax(290px, 0.78fr); align-items: start; gap: 22px; }
.calculator-panel, .result-panel { border: 1px solid var(--line); border-radius: var(--radius-lg); background: var(--surface); box-shadow: 0 7px 24px rgba(25, 40, 31, 0.035); }
.calculator-panel { padding: clamp(22px, 4vw, 34px); }
.calculator-panel h2, .result-panel h2 { font-size: 1.25rem; line-height: 1.2; }
.calculator-panel > p { margin: 9px 0 28px; color: var(--ink-muted); font-size: 0.93rem; }

.field-list { display: grid; gap: 18px; }
.field { display: grid; gap: 7px; }
.field-label { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; font-size: 0.91rem; font-weight: 700; letter-spacing: -0.01em; }
.field-helper { color: var(--ink-faint); font-size: 0.78rem; font-weight: 500; text-align: right; }
.field-control { position: relative; display: flex; align-items: center; }
.field-prefix, .field-suffix { position: absolute; z-index: 1; color: var(--ink-muted); pointer-events: none; }
.field-prefix { left: 14px; }
.field-suffix { right: 14px; }
.field-control.has-prefix input { padding-left: 34px; }
.field-control.has-suffix input { padding-right: 39px; }
.field input, .field select {
  width: 100%;
  min-height: 49px;
  padding: 11px 13px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  outline: 0;
  background: #fff;
  color: var(--ink);
  font-variant-numeric: tabular-nums;
  transition: border-color var(--ease), box-shadow var(--ease), background var(--ease);
}
.field select { cursor: pointer; }
.field input:focus, .field select:focus { border-color: var(--brand); box-shadow: 0 0 0 4px rgba(22, 107, 82, 0.12); }
.field [aria-invalid="true"] { border-color: var(--danger); background: #fffafa; }
.field-error { min-height: 17px; color: var(--danger); font-size: 0.79rem; }

.form-actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 25px; }
.calculator-note { margin: 18px 0 0; color: var(--ink-faint); font-size: 0.79rem; line-height: 1.52; }

.result-panel { position: sticky; top: 20px; min-height: 320px; overflow: hidden; }
.result-top { padding: clamp(24px, 4vw, 34px); background: linear-gradient(145deg, var(--brand-dark), var(--brand)); color: #fff; }
.result-kicker { margin: 0; color: #cae9d8; font-size: 0.82rem; font-weight: 690; letter-spacing: 0.02em; }
.result-value { margin: 10px 0 0; font-size: clamp(2.45rem, 5vw, 3.55rem); font-weight: 760; letter-spacing: -0.065em; line-height: 1; font-variant-numeric: tabular-nums; overflow-wrap: anywhere; }
.result-subtitle { margin: 12px 0 0; color: #dcf2e5; font-size: 0.88rem; line-height: 1.5; }
.result-details { display: grid; padding: 10px 25px 20px; }
.result-detail { display: flex; justify-content: space-between; gap: 20px; padding: 14px 0; border-bottom: 1px solid var(--line); }
.result-detail:last-child { border-bottom: 0; }
.result-detail dt { color: var(--ink-muted); font-size: 0.88rem; }
.result-detail dd { margin: 0; color: var(--ink); font-weight: 730; text-align: right; font-variant-numeric: tabular-nums; }
.result-empty { display: grid; min-height: 320px; place-items: center; padding: 30px; color: var(--ink-muted); text-align: center; }
.result-empty svg { width: 35px; height: 35px; margin-bottom: 12px; color: var(--brand); }
.result-empty p { max-width: 240px; margin: 0; }

.explanation-grid { display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(260px, 0.8fr); gap: 20px; margin-top: 52px; }
.explanation-card, .related-card { padding: clamp(22px, 4vw, 32px); border: 1px solid var(--line); border-radius: var(--radius-lg); background: #fff; }
.explanation-card h2, .related-card h2 { font-size: 1.35rem; }
.explanation-card > p { margin: 13px 0 0; color: var(--ink-muted); line-height: 1.65; }
.formula-box { margin-top: 19px; padding: 16px; border-radius: var(--radius-sm); background: var(--surface-soft); color: var(--brand-dark); font-family: ui-monospace, SFMono-Regular, Consolas, monospace; font-size: 0.86rem; line-height: 1.6; overflow-wrap: anywhere; }
.explanation-card details { margin-top: 18px; border-top: 1px solid var(--line); }
.explanation-card summary { padding: 17px 0 0; cursor: pointer; font-weight: 710; }
.explanation-card details p { color: var(--ink-muted); line-height: 1.62; }
.related-list { display: grid; gap: 9px; margin-top: 18px; }
.related-link { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 13px 0; border-bottom: 1px solid var(--line); color: var(--brand-dark); font-weight: 680; }
.related-link svg { width: 17px; height: 17px; flex: 0 0 auto; }

.legal-page { max-width: 780px; padding: 62px 0 96px; }
.legal-page h1 { font-size: clamp(2.6rem, 6vw, 4.65rem); }
.legal-page .lead { max-width: 620px; margin: 18px 0 38px; color: var(--ink-muted); font-size: 1.08rem; line-height: 1.65; }
.legal-page section { margin-top: 32px; }
.legal-page h2 { font-size: 1.5rem; }
.legal-page p, .legal-page li { color: var(--ink-muted); line-height: 1.68; }
.legal-page ul { padding-left: 21px; }
.legal-page a { color: var(--brand-dark); text-decoration: underline; text-underline-offset: 3px; }

.noscript-note { margin-top: 26px; color: var(--ink-muted); }
.noscript-links { display: grid; gap: 8px; padding-left: 20px; }
.noscript-links a { color: var(--brand-dark); text-decoration: underline; }

@media (max-width: 780px) {
  :root { --shell: min(100% - 32px, 1120px); }
  .header-inner { min-height: 66px; }
  .primary-nav { gap: 15px; font-size: 0.83rem; }
  .search-control { align-items: stretch; flex-wrap: wrap; gap: 8px; padding: 10px 10px 10px 15px; }
  .search-control > svg { margin-top: 12px; }
  .search-control input { width: calc(100% - 36px); flex: auto; }
  .search-control .button { width: 100%; }
  .section-heading { align-items: flex-start; flex-direction: column; }
  .filter-row { justify-content: flex-start; }
  .tool-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .principles, .calculator-layout, .explanation-grid { grid-template-columns: 1fr; }
  .result-panel { position: static; }
  .footer-inner { align-items: flex-start; flex-direction: column; justify-content: center; padding: 28px 0; }
}

@media (max-width: 520px) {
  .primary-nav a:last-child { display: none; }
  .tool-grid { grid-template-columns: 1fr; }
  .tool-card { min-height: 144px; }
  .calculator-page { padding-top: 26px; }
  .breadcrumb { margin-bottom: 28px; }
  .result-detail { gap: 13px; }
  .result-detail dd { max-width: 52%; }
  .site-footer nav { flex-wrap: wrap; gap: 12px 18px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; }
}