:root {
  color-scheme: light;
  --ink: #18201c;
  --muted: #5e6a63;
  --surface: #ffffff;
  --canvas: #f3f5f1;
  --line: #d9dfda;
  --accent: #225c3d;
  --accent-dark: #17452d;
  --accent-soft: #e5f2e9;
  --warm: #f4e8d7;
  --error: #a32929;
  --shadow: 0 18px 50px rgb(24 32 28 / 10%);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--canvas);
  font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 1rem;
  line-height: 1.55;
}

button,
input,
select {
  font: inherit;
}

.shell {
  width: min(100% - 2rem, 70rem);
  margin-inline: auto;
}

.skip-link {
  position: fixed;
  z-index: 10;
  top: 0.75rem;
  left: 0.75rem;
  padding: 0.65rem 0.9rem;
  color: #fff;
  background: var(--accent-dark);
  border-radius: 0.35rem;
  transform: translateY(-180%);
}

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

.site-header {
  padding-block: 1.1rem;
  background: var(--surface);
  border-bottom: 1px solid var(--line);
}

.brand {
  color: var(--ink);
  font-weight: 750;
  letter-spacing: -0.02em;
  text-decoration: none;
}

.brand:focus-visible,
.brand:hover {
  color: var(--accent);
}

.hero {
  padding: clamp(2.25rem, 6vw, 5rem) 0 clamp(3.5rem, 7vw, 6rem);
  background:
    radial-gradient(circle at 92% 12%, rgb(244 232 215 / 85%) 0 7rem, transparent 7.1rem),
    var(--canvas);
}

.eyebrow {
  margin: 0 0 0.4rem;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

h1,
h2,
p {
  text-wrap: pretty;
}

h1 {
  max-width: 16ch;
  margin: 0;
  font-size: clamp(2.15rem, 6vw, 4.25rem);
  line-height: 1.03;
  letter-spacing: -0.045em;
}

.intro {
  max-width: 42rem;
  margin: 1rem 0 2rem;
  color: var(--muted);
  font-size: clamp(1.05rem, 2vw, 1.25rem);
}

.calculator {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(18rem, 0.75fr);
  overflow: hidden;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 1rem;
  box-shadow: var(--shadow);
}

.calculator:focus {
  outline: 3px solid rgb(34 92 61 / 38%);
  outline-offset: 4px;
}

.calculator__form {
  display: grid;
  gap: 1.6rem;
  padding: clamp(1.25rem, 4vw, 2.25rem);
}

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

legend {
  width: 100%;
  margin-bottom: 1rem;
  padding: 0 0 0.55rem;
  border-bottom: 1px solid var(--line);
  font-size: 1.1rem;
  font-weight: 750;
}

.field,
.field-row {
  min-width: 0;
}

fieldset > .field + .field,
.field + .field-row,
.field-row + .field {
  margin-top: 1rem;
}

.field-row {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

label {
  display: inline-block;
  margin-bottom: 0.4rem;
  font-weight: 700;
}

select,
input[type="number"] {
  width: 100%;
  min-height: 3rem;
  color: var(--ink);
  background: #fff;
  border: 1px solid #aeb8b1;
  border-radius: 0.45rem;
}

select {
  padding: 0.65rem 2.5rem 0.65rem 0.75rem;
}

.input-with-unit {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  overflow: hidden;
  background: #edf0ed;
  border: 1px solid #aeb8b1;
  border-radius: 0.45rem;
}

.input-with-unit input {
  min-width: 0;
  padding: 0.65rem 0.75rem;
  border: 0;
  border-radius: 0;
}

.input-with-unit span {
  padding-inline: 0.8rem;
  color: var(--muted);
  font-weight: 700;
}

select:focus-visible,
input:focus-visible,
.input-with-unit:focus-within {
  outline: 3px solid rgb(34 92 61 / 28%);
  outline-offset: 2px;
  border-color: var(--accent);
}

.input-with-unit input:focus-visible {
  outline: 0;
}

.input-with-unit input[aria-invalid="true"] {
  box-shadow: inset 0 0 0 2px var(--error);
}

.hint {
  margin: 0.45rem 0 0;
  color: var(--muted);
  font-size: 0.86rem;
}

.label-line,
.range-labels {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
}

.label-line output {
  color: var(--accent);
  font-weight: 800;
}

input[type="range"] {
  width: 100%;
  min-height: 2rem;
  margin: 0;
  accent-color: var(--accent);
  cursor: pointer;
}

.range-labels {
  margin-top: -0.25rem;
  color: var(--muted);
  font-size: 0.78rem;
}

.form-error {
  min-height: 1.5em;
  margin: -0.75rem 0 0;
  color: var(--error);
  font-weight: 700;
}

.results {
  display: flex;
  min-width: 0;
  flex-direction: column;
  padding: clamp(1.25rem, 4vw, 2.25rem);
  color: #fff;
  background: var(--accent-dark);
}

.results__label {
  margin: 0 0 1.25rem;
  color: #c9dfd1;
  font-size: 0.8rem;
  font-weight: 800;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.result-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
}

.result {
  padding: 1rem;
  background: rgb(255 255 255 / 8%);
  border: 1px solid rgb(255 255 255 / 14%);
  border-radius: 0.65rem;
}

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

.result span {
  min-height: 2.7em;
  color: #dce9e1;
  font-size: 0.82rem;
}

.result strong {
  display: block;
  margin-top: 0.25rem;
  font-size: clamp(1.4rem, 3vw, 2rem);
  line-height: 1.1;
}

.buy-result {
  margin-top: 1rem;
  padding: 1.35rem;
  color: var(--ink);
  background: var(--warm);
  border-radius: 0.75rem;
}

.buy-result span {
  font-weight: 750;
}

.buy-result strong {
  display: block;
  margin-block: 0.15rem;
  color: var(--accent-dark);
  font-size: clamp(2.6rem, 7vw, 4.5rem);
  line-height: 1;
}

.buy-result small {
  color: #4c564f;
}

.results__note {
  margin: auto 0 0;
  padding-top: 1.5rem;
  color: #c9dfd1;
  font-size: 0.9rem;
}

.explanation {
  padding-block: clamp(3.5rem, 8vw, 6rem);
  background: var(--surface);
}

.content-shell {
  max-width: 47rem;
}

h2 {
  margin: 0 0 1rem;
  font-size: clamp(1.7rem, 4vw, 2.4rem);
  line-height: 1.15;
  letter-spacing: -0.025em;
}

.explanation p {
  color: var(--muted);
}

.explanation p:last-child {
  margin-bottom: 0;
}

.site-footer {
  padding-block: 1.4rem;
  color: var(--muted);
  background: var(--canvas);
  border-top: 1px solid var(--line);
  font-size: 0.86rem;
}

.site-footer p {
  margin: 0;
}

@media (max-width: 48rem) {
  .hero {
    padding-top: 2.5rem;
  }

  .calculator {
    grid-template-columns: 1fr;
  }

  .results__note {
    margin-top: 1.5rem;
  }
}

@media (max-width: 32rem) {
  .shell {
    width: min(100% - 1.25rem, 70rem);
  }

  .field-row,
  .result-grid {
    grid-template-columns: 1fr;
  }

  .result span {
    min-height: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}