:root {
  --bg: #f7f6f2;
  --surface: #ffffff;
  --text: #1b1a17;
  --muted: #5c5850;
  --line: #e3ded4;
  --accent: #0b6b6b;
  --accent-soft: #e3f1ef;
  --warn: #b42318;
  --measure: 64rem;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1415;
    --surface: #161d1e;
    --text: #ece9e2;
    --muted: #a39f95;
    --line: #2a3334;
    --accent: #5cc6be;
    --accent-soft: #173130;
    --warn: #ff8a7a;
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.65 ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

a { color: var(--accent); text-underline-offset: 0.18em; }
a:hover { text-decoration-thickness: 2px; }

.site-header, .site-footer, main {
  max-width: var(--measure);
  margin: 0 auto;
  padding: 0 1rem;
}

.site-header {
  padding-top: 1.5rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--line);
}

.brand {
  color: var(--text);
  font-weight: 700;
  letter-spacing: -0.01em;
  text-decoration: none;
}

main { padding-top: 2.5rem; padding-bottom: 3rem; }

h1 {
  font-size: clamp(1.9rem, 5vw, 2.5rem);
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin: 0 0 0.5rem;
}

.lede { color: var(--muted); font-size: 1.05rem; margin: 0 0 1.5rem; }

.site-footer {
  border-top: 1px solid var(--line);
  padding-top: 1.25rem;
  padding-bottom: 2rem;
  color: var(--muted);
  font-size: 0.9rem;
}
.site-footer p { margin: 0; }

/* Calculator */

.calc { display: grid; gap: 1.5rem; }
@media (min-width: 48rem) {
  .calc { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); align-items: start; }
}

.panel {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 1.25rem 1.35rem;
}

.panel h2, legend {
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
  margin: 0 0 0.5rem;
  padding: 0;
}

fieldset { border: 0; margin: 0 0 1.5rem; padding: 0; min-width: 0; }

.inputs label, .results dl div {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.4rem 0;
  border-bottom: 1px solid var(--line);
}
.inputs label > span:first-child { flex: 1; }
.inputs label:has(+ .note) { border-bottom: 0; }
.inputs .note {
  margin: 0;
  padding: 0 0 0.5rem;
  border-bottom: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.85rem;
  line-height: 1.5;
}

.field { display: flex; align-items: center; gap: 0.3rem; color: var(--muted); }
.field input {
  width: 7.5rem;
  font: inherit;
  color: var(--text);
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0.3rem 0.5rem;
  text-align: right;
  font-variant-numeric: tabular-nums;
}
.field input:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }
.field input[aria-invalid="true"] { border-color: var(--warn); box-shadow: 0 0 0 1px var(--warn); outline-color: var(--warn); }
.unit { flex: none; width: 1em; text-align: center; }
@media (max-width: 22.5rem) {
  .panel { padding: 1rem; }
  .field input { width: 6.5rem; }
}
.hint { color: var(--warn); font-size: 0.9rem; margin: 0 0 1rem; }

.actions { display: flex; flex-wrap: wrap; align-items: center; gap: 0.75rem; }
button {
  font: inherit;
  font-size: 0.95rem;
  padding: 0.45rem 0.95rem;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--text);
  cursor: pointer;
}
button.primary { background: var(--accent); border-color: var(--accent); color: var(--surface); }
button:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
#copied { color: var(--accent); font-size: 0.9rem; }

.results dl { margin: 0 0 1.5rem; }
.results dt { color: var(--muted); }
.results dd { margin: 0; font-weight: 600; font-variant-numeric: tabular-nums; }
.results .key dd { font-size: 1.2rem; }
.footnote { color: var(--muted); font-size: 0.85rem; margin: 0; }

.list { padding-left: 1.25rem; }
.list li { margin-bottom: 0.35rem; }