:root {
  color-scheme: light;
  --bg: #f3f0e7;
  --bg-2: #e6efe4;
  --paper: #fffdf8;
  --ink: #13241b;
  --muted: #51675b;
  --line: #d5dfd4;
  --mark: #0d3b28;
  --accent: #0d3b28;
  --lime: #dff56a;
  --lime-ink: #14240a;
  --focus: #0b6b3a;
  --danger: #9d2c2c;
  --shadow: 0 22px 50px rgba(19, 36, 27, 0.1);
  --serif: "Nimbus Roman", "Liberation Serif", "Times New Roman", serif;
  --sans: "Adwaita Sans", "Liberation Sans", "Segoe UI", sans-serif;
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0c1210;
  --bg-2: #101a16;
  --paper: #17211c;
  --ink: #e8f3ec;
  --muted: #a9c0b3;
  --line: #2b3d34;
  --mark: #143528;
  --accent: #d7f5a8;
  --focus: #dff56a;
  --danger: #ffb4b4;
  --shadow: 0 22px 50px rgba(0, 0, 0, 0.35);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --bg: #0c1210;
    --bg-2: #101a16;
    --paper: #17211c;
    --ink: #e8f3ec;
    --muted: #a9c0b3;
    --line: #2b3d34;
    --mark: #143528;
    --accent: #d7f5a8;
    --focus: #dff56a;
    --danger: #ffb4b4;
    --shadow: 0 22px 50px rgba(0, 0, 0, 0.35);
  }
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background:
    radial-gradient(900px 420px at 0% -10%, var(--bg-2), transparent 60%),
    var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 1.05rem;
  line-height: 1.5;
}

img {
  max-width: 100%;
  height: auto;
}

button,
input,
textarea {
  font: inherit;
  color: inherit;
}

a {
  color: inherit;
}

:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
}

.skip {
  position: absolute;
  left: 12px;
  top: -48px;
  z-index: 40;
  background: var(--lime);
  color: var(--lime-ink);
  padding: 8px 12px;
  border-radius: 8px;
}

.skip:focus {
  top: 12px;
}

.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;
}

#calculator,
section[id],
#storage-note {
  scroll-margin-top: 84px;
}

.wrap {
  width: min(1120px, calc(100% - 32px));
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}

.header-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  min-height: 68px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  text-decoration: none;
  letter-spacing: -0.02em;
}

.mark {
  width: 32px;
  height: 32px;
  display: grid;
  place-items: center;
  border-radius: 9px;
  background: var(--mark);
  color: var(--lime);
  font-family: var(--serif);
  font-size: 1.35rem;
  line-height: 1;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 22px;
  margin-left: 18px;
}

.site-nav a {
  text-decoration: none;
  font-size: 0.95rem;
  color: var(--muted);
}

.site-nav a:hover {
  color: var(--ink);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-left: auto;
}

.btn.nav-toggle {
  display: none;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 16px;
  border-radius: 999px;
  border: 1px solid transparent;
  text-decoration: none;
  background: transparent;
  cursor: pointer;
  font-weight: 600;
}

.btn-primary {
  background: var(--lime);
  color: var(--lime-ink);
}

.btn-primary:hover {
  filter: brightness(1.05);
}

.btn-ghost {
  border-color: var(--line);
  background: var(--paper);
  color: var(--ink);
}

.btn-ghost:hover {
  border-color: var(--ink);
}

.btn-on-dark {
  border-color: rgba(255, 255, 255, 0.28);
  background: transparent;
  color: #f3fff6;
}

.hero {
  padding: 48px 0 140px;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(280px, 0.9fr);
  gap: 36px;
  align-items: start;
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--accent);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

h1,
h2,
.stat strong,
.calc dd {
  font-family: var(--serif);
  font-weight: 700;
  letter-spacing: -0.03em;
}

h1 {
  margin: 0;
  font-size: clamp(2.5rem, 5vw, 4.4rem);
  line-height: 0.96;
}

.lede {
  max-width: 38rem;
  color: var(--muted);
  font-size: 1.12rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 20px 0 22px;
}

.shot {
  width: 100%;
  object-fit: cover;
  border-radius: 18px;
  border: 1px solid var(--line);
  background: var(--paper);
}

.hero .shot {
  height: 220px;
}

.calc {
  background: radial-gradient(500px 220px at 100% 0%, #1d6a48, transparent 55%), var(--mark);
  color: #e9f6ee;
  border: 1px solid color-mix(in srgb, var(--lime) 32%, transparent);
  border-radius: 24px;
  padding: 24px;
  box-shadow: var(--shadow);
}

.calc h2 {
  margin: 0 0 6px;
  font-size: 2rem;
  line-height: 1;
  color: white;
}

.calc .eyebrow {
  color: var(--lime);
}

.fields {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-top: 16px;
}

.calc label,
.contact-form label {
  display: grid;
  gap: 6px;
  font-size: 0.84rem;
  font-weight: 600;
}

.calc label {
  color: #c9e0d4;
}

.calc input,
.contact-form input,
.contact-form textarea {
  width: 100%;
  min-height: 44px;
  padding: 10px 12px;
  border-radius: 12px;
  border: 1px solid var(--line);
  background: var(--paper);
}

.calc input {
  border-color: rgba(255, 255, 255, 0.16);
  background: rgba(255, 255, 255, 0.08);
  color: white;
}

.calc input:focus-visible,
.contact-form input:focus-visible,
.contact-form textarea:focus-visible {
  outline-color: var(--lime);
}

.results {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin: 16px 0 8px;
}

.results div {
  background: rgba(0, 0, 0, 0.18);
  border-radius: 14px;
  padding: 12px;
}

.results .wide {
  grid-column: 1 / -1;
}

.results dt {
  color: #c9e0d4;
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.results dd {
  margin: 4px 0 0;
  color: var(--lime);
  font-size: 2rem;
  line-height: 1;
}

.results .wide dd {
  font-size: 2.6rem;
}

.formula,
.calc-error,
.calc-status,
.field-error,
.form-status {
  min-height: 1.3em;
  margin: 8px 0 0;
  font-size: 0.9rem;
}

.formula,
.calc-status {
  color: #c9e0d4;
}

.calc-error,
.field-error {
  color: #ffb4b4;
}

.field-error {
  color: var(--danger);
}

.field-error:empty {
  display: none;
}

.calc-actions {
  margin-top: 12px;
}

.section {
  padding: 64px 0;
}

.section h2 {
  margin: 0 0 8px;
  font-size: clamp(2rem, 4vw, 3.2rem);
  line-height: 1;
}

.section-intro {
  max-width: 40rem;
  margin: 0;
  color: var(--muted);
}

.cards,
.stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-top: 28px;
}

.card,
.stat,
.quote,
.note,
.contact-form,
.panel {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 18px;
}

.card,
.stat {
  padding: 22px;
}

.card h3,
.note strong {
  margin: 0 0 8px;
  font-size: 1.15rem;
}

.card p,
.quote p,
.note p {
  margin: 0;
  color: var(--muted);
}

.index {
  display: inline-grid;
  place-items: center;
  width: 36px;
  height: 36px;
  margin-bottom: 12px;
  border-radius: 50%;
  background: var(--bg-2);
  color: var(--accent);
  font-weight: 700;
}

.band {
  background: color-mix(in srgb, var(--bg-2) 75%, var(--bg));
}

.stat {
  text-align: center;
}

.stat strong {
  display: block;
  color: var(--accent);
  font-size: 3rem;
  line-height: 1;
}

.stat span {
  color: var(--muted);
}

.quotes {
  display: grid;
  gap: 14px;
  margin-top: 16px;
}

.quote {
  padding: 20px 22px;
  border-left: 4px solid var(--lime);
}

.quote footer {
  margin-top: 10px;
  font-weight: 600;
}

.split {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: 32px;
  align-items: center;
  margin-top: 8px;
}

.about .shot {
  height: 360px;
}

.ticks {
  margin: 16px 0 0;
  padding: 0;
  list-style: none;
}

.ticks li {
  position: relative;
  padding-left: 22px;
  margin: 8px 0;
}

.ticks li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--lime);
  box-shadow: inset 0 0 0 2px var(--mark);
}

.contact-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: 20px;
  margin-top: 28px;
}

.contact-form,
.panel {
  padding: 22px;
  display: flex;
  flex-direction: column;
}

#empty-notes:not([hidden]) {
  flex: 1;
  display: grid;
  place-items: center;
  text-align: center;
  margin-top: 16px;
  padding: 28px 18px;
  border: 1px dashed var(--line);
  border-radius: 14px;
}

.contact-form {
  display: grid;
  gap: 12px;
}

.contact-form textarea {
  min-height: 120px;
  resize: vertical;
}

.form-help {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.form-status {
  color: var(--ink);
  font-weight: 600;
}

.empty {
  margin: 0;
  color: var(--muted);
}

.notes {
  display: grid;
  gap: 12px;
  margin-top: 14px;
}

.note {
  padding: 14px;
}

.note-head {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: baseline;
}

.note-head time,
.note-meta {
  color: var(--muted);
  font-size: 0.88rem;
}

.note-actions {
  display: flex;
  gap: 8px;
  margin-top: 12px;
}

.note-actions .btn {
  min-height: 40px;
}

.fineprint {
  margin-top: 36px;
  max-width: 46rem;
}

.fineprint h2 {
  font-size: 1.6rem;
}

.site-footer {
  border-top: 1px solid var(--line);
  padding: 22px 0 32px;
}

.footer-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 20px;
  align-items: center;
  justify-content: space-between;
  color: var(--muted);
  font-size: 0.92rem;
}

.footer-bar nav {
  display: flex;
  gap: 16px;
}

.footer-bar a {
  color: var(--muted);
}

@media (max-width: 860px) {
  .btn.nav-toggle {
    display: inline-flex;
  }

  .site-nav {
    display: none;
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    margin: 0;
    padding: 8px 16px 16px;
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    background: var(--paper);
    border-bottom: 1px solid var(--line);
  }

  .site-nav a {
    padding: 10px 4px;
  }

  body.nav-open .site-nav {
    display: flex;
  }

  .hero-grid,
  .cards,
  .stats,
  .split,
  .contact-grid {
    grid-template-columns: 1fr;
  }

  .about .shot,
  .hero .shot {
    height: 200px;
  }
}

@media (max-width: 520px) {
  .fields,
  .results {
    grid-template-columns: 1fr;
  }

  .results .wide {
    grid-column: auto;
  }

  .header-bar .book {
    display: none;
  }

  h1 {
    font-size: 2.35rem;
  }

  .results dd,
  .results .wide dd,
  .stat strong {
    font-size: 2.2rem;
  }
}

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

  *,
  *::before,
  *::after {
    transition: none !important;
  }
}