:root {
  --bg: #f7f8f6;
  --panel: #ffffff;
  --ink: #1d2521;
  --muted: #5b6660;
  --line: #d9ded9;
  --accent: #1f5f4a;
  --accent-soft: #e5f0eb;
  --accent-ink: #ffffff;
  --eyebrow: #4a6b5c;
  --head-bg: #ffffff;
  --shadow: 0 1px 2px rgba(29, 37, 33, .06);
  --radius: 10px;
  --radius-sm: 8px;
  --good: #1b6b3a;
  --bad: #a3271f;
  --focus: #c27c0e;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #131815;
    --panel: #1c2320;
    --ink: #e8ece9;
    --muted: #a3ada7;
    --line: #34403a;
    --accent: #7cc4a4;
    --accent-soft: #233a30;
    --accent-ink: #0f1a15;
    --eyebrow: #8fb8a4;
    --head-bg: #1c2320;
    --shadow: none;
    --good: #7fd49a;
    --bad: #f08a80;
    --focus: #f2b44c;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.55 system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
}
a { color: var(--accent); }
a:focus-visible, button:focus-visible, input:focus-visible, select:focus-visible, summary:focus-visible, .btn:focus-visible, .calc-nav a:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 2px;
}
.skip { position: absolute; left: -999px; }
.skip:focus { left: 16px; top: 8px; background: var(--panel); padding: 8px 12px; z-index: 10; }

/* Shell: full width, no centered column */
header.site, main, footer.site { width: 100%; margin: 0; padding: 0 16px; }
@media (min-width: 820px) { header.site, main, footer.site { padding-left: 32px; padding-right: 32px; } }
main { padding-top: 20px; }
main > h1:first-child, .hero > h1:first-child, .article-head > h1:first-child, main > .eyebrow:first-child, .hero > .eyebrow:first-child, .article-head > .eyebrow:first-child { margin-top: 0; }
header.site { background: var(--head-bg); border-bottom: 1px solid var(--line); padding-top: 14px; padding-bottom: 14px; }
.head-row { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px; }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--ink); font-weight: 700; font-size: 18px; }
.brand-mark { width: 28px; height: 28px; border: 0; display: block; }
.brand-sub { font-weight: 400; color: var(--muted); font-size: 14px; }
.head-links { display: flex; gap: 4px; }
.head-links a, .calc-nav a { padding: 6px 10px; border-radius: 999px; text-decoration: none; color: var(--ink); font-size: 14px; line-height: 1.2; }
.head-links a:hover, .head-links a:focus-visible, .calc-nav a:hover, .calc-nav a:focus-visible { background: var(--accent-soft); }
.calc-nav { margin-top: 10px; display: flex; flex-wrap: wrap; gap: 4px 6px; }
.head-links a[aria-current="page"], .calc-nav a[aria-current="page"] { font-weight: 700; background: var(--accent); color: var(--accent-ink); text-decoration: none; border-bottom: 0; }

/* Type */
h1 { font-size: clamp(28px, 1.2vw + 20px, 40px); letter-spacing: -0.01em; line-height: 1.15; margin: 20px 0 8px; }
h2 { font-size: 19px; margin: 0 0 10px; }
.eyebrow { font-size: 12px; text-transform: uppercase; letter-spacing: .08em; font-weight: 700; color: var(--eyebrow); margin: 0 0 6px; }
.eyebrow + h1 { margin-top: 0; }
.lede { color: var(--muted); font-size: 18px; margin: 0 0 24px; max-width: 70ch; }

/* Buttons */
.btn, .btn-ghost, button[type="submit"], .upsell .shop-link {
  display: inline-flex; align-items: center; gap: 8px; padding: 10px 16px; min-height: 40px;
  border-radius: var(--radius-sm); border: 1px solid var(--accent); font-weight: 700; text-decoration: none;
}
.btn, button[type="submit"], .upsell .shop-link { background: var(--accent); color: var(--accent-ink); }
.btn:hover, button[type="submit"]:hover, .upsell .shop-link:hover { filter: brightness(1.08); color: var(--accent-ink); }
.btn-ghost { background: transparent; color: var(--accent); }
.btn-ghost:hover { background: var(--accent-soft); }
@media (prefers-color-scheme: dark) { .btn:hover, button[type="submit"]:hover, .upsell .shop-link:hover { filter: brightness(1.1); } }

/* Home */
.trust { list-style: none; padding: 0; margin: 0 0 20px; display: flex; flex-wrap: wrap; gap: 8px; }
.trust li { display: inline-flex; align-items: center; gap: 6px; padding: 6px 12px; border: 1px solid var(--line); border-radius: 999px; background: var(--panel); font-size: 14px; color: var(--ink); }
.dot { width: 8px; height: 8px; border-radius: 50%; background: var(--good); flex: none; }
.hero { margin-top: 0; }
.hero-cta { display: flex; flex-wrap: wrap; gap: 10px; margin: 0 0 28px; }
.section-h { font-size: 22px; margin: 36px 0 12px; }
.trust-strip { display: grid; grid-template-columns: minmax(0, 1fr); gap: 16px; margin-top: 36px; }
@media (min-width: 820px) { .trust-strip { grid-template-columns: repeat(3, minmax(0, 1fr)); } }
.trust-strip > div { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px; }
.trust-strip h2 { font-size: 17px; margin: 0 0 6px; }
.trust-strip p { margin: 0; color: var(--muted); font-size: 15px; }

/* Calculator layout */
.calc { display: grid; grid-template-columns: 1fr; gap: 20px; align-items: start; }
@media (min-width: 820px) { .calc { grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr); } .results { position: sticky; top: 16px; } }

.panel { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); padding: 18px; }
@media (min-width: 820px) { .panel { padding: 20px; } }
fieldset { border: 0; padding: 0; margin: 0 0 14px; }
legend { font-weight: 700; padding: 0; margin-bottom: 8px; }
.field { display: grid; grid-template-columns: 1fr 9.5em; gap: 8px; align-items: center; margin-bottom: 8px; }
.field label { font-size: 15px; }
.field .hint { grid-column: 1 / -1; margin-top: -6px; font-size: 13px; color: var(--muted); }
.unit { position: relative; }
.unit input, .field select { width: 100%; }
.unit[data-pre]::before, .unit[data-post]::after {
  position: absolute; top: 50%; transform: translateY(-50%); color: var(--muted); font-size: 14px; pointer-events: none;
}
.unit[data-pre]::before { content: attr(data-pre); left: 9px; }
.unit[data-post]::after { content: attr(data-post); right: 9px; }
.unit[data-pre] input { padding-left: 22px; }
.unit[data-post] input { padding-right: 34px; }
input, select {
  font: inherit; color: var(--ink); background: var(--bg);
  border: 1px solid var(--line); border-radius: 6px; padding: 7px 9px; min-height: 40px;
}
input { text-align: right; }
.actions { display: flex; gap: 10px; flex-wrap: wrap; }
button {
  font: inherit; cursor: pointer; border-radius: var(--radius-sm); padding: 8px 14px; min-height: 40px;
  border: 1px solid var(--accent); background: transparent; color: var(--accent);
}
button[type="submit"] { font: inherit; font-weight: 700; padding: 10px 16px; }

/* Results */
.results h2 { font-size: 17px; margin: 0 0 2px; }
.results-note { margin: 0 0 12px; font-size: 13px; color: var(--muted); }
.results dl { margin: 0; }
.row { display: flex; justify-content: space-between; gap: 12px; padding: 6px 0; border-bottom: 1px solid var(--line); }
.row:last-child { border-bottom: 0; }
.row dt { color: var(--muted); }
.row dd { margin: 0; font-variant-numeric: tabular-nums; text-align: right; font-weight: 600; }
.row.key dt { color: var(--ink); font-weight: 700; }
.row.key dd { font-size: 20px; color: var(--accent); }
.results h3 { font-size: 12px; text-transform: uppercase; letter-spacing: .08em; color: var(--eyebrow); margin: 18px 0 4px; }
output { font-variant-numeric: tabular-nums; }
output.neg { color: var(--bad); }
output.good { color: var(--good); }
output.bad { color: var(--bad); }

/* Headline tiles */
.summary > dl { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; }
@media (min-width: 820px) { .summary > dl { grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); } }
.summary > dl .row { display: flex; flex-direction: column; align-items: flex-start; justify-content: flex-start; gap: 2px; padding: 12px 14px; border: 1px solid var(--line); border-radius: var(--radius-sm); background: var(--bg); min-width: 0; }
.summary > dl .row dt { font-size: 13px; color: var(--muted); font-weight: 400; }
.summary > dl .row dd { font-size: 22px; font-weight: 700; text-align: left; color: var(--ink); overflow-wrap: anywhere; }
.summary > dl .row.key { background: var(--accent-soft); border-color: transparent; }
.summary > dl .row.key dt { color: var(--ink); font-weight: 600; }
.summary > dl .row.key dd { font-size: 26px; color: var(--accent); }
.summary > dl .row dd output.neg, .summary > dl .row dd output.bad { color: var(--bad); }
.summary > dl .row dd output.good { color: var(--good); }

.how { margin-top: 16px; }
.how summary { cursor: pointer; font-weight: 700; font-size: 17px; padding: 4px 0; }
.how ol, .how ul { padding-left: 20px; }
.how ol { margin-top: 8px; }
.how li { margin-bottom: 4px; }
code, .formula { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 14px; }
.formula { display: block; background: var(--accent-soft); border-radius: 6px; padding: 8px 10px; margin: 6px 0; overflow-wrap: anywhere; }

.upsell { margin-top: 24px; background: var(--accent-soft); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 20px; }
.upsell .eyebrow { margin: 0 0 4px; }
.upsell p { margin: 0; }
.upsell a { font-weight: 700; }
.upsell .shop-link { display: inline-block; margin-top: 8px; }

/* Cards */
.cards { list-style: none; padding: 0; margin: 0; display: grid; gap: 16px; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); }
@media (min-width: 1400px) { .cards { grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); } }
.cards li { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px; box-shadow: var(--shadow); display: flex; flex-direction: column; gap: 8px; }
.cards li:hover { border-color: var(--accent); }
.cards h3 { font-size: 19px; margin: 0; }
.cards h3 a { color: var(--ink); text-decoration: none; }
.cards h3 a:hover { text-decoration: underline; }
.cards p { margin: 0; color: var(--muted); flex: 1; }
.cards .eyebrow { flex: none; color: var(--eyebrow); }
.card-links { display: flex; flex-wrap: wrap; gap: 8px 16px; align-items: center; margin-top: 6px; font-size: 14px; }
.card-links .open { font-weight: 700; text-decoration: none; color: var(--accent); }
.card-links .open:hover { text-decoration: underline; }
.cards .more { font-size: 14px; color: var(--muted); }
.cards .more:hover { color: var(--accent); }
.shop-link { font-weight: 700; }

/* Email sign-up */
.signup { margin-top: 24px; background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px; max-width: 75ch; }
.signup h2 { margin: 0 0 4px; }
.signup p { margin: 0 0 10px; }
.signup-form { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; margin-bottom: 8px; }
.signup-form label { flex: 1 1 100%; font-size: 15px; }
.signup-form input { flex: 1 1 16em; text-align: left; }
.signup-note, .signup-status { font-size: 14px; color: var(--muted); }
.signup-status { margin-bottom: 0; color: var(--ink); }
.signup-status:empty { display: none; }
main:has(.calc) > .signup { max-width: none; }
.prose ul { padding-left: 22px; margin: 0 0 10px; }

/* Footer */
footer.site { margin-top: 48px; padding-top: 28px; padding-bottom: 40px; border-top: 1px solid var(--line); color: var(--muted); font-size: 14px; }
.foot-grid { display: grid; grid-template-columns: minmax(0, 1fr); gap: 24px 48px; }
@media (min-width: 820px) { .foot-grid { grid-template-columns: minmax(0, 1.4fr) repeat(2, minmax(0, 1fr)); } }
.foot-name { color: var(--ink); font-weight: 700; font-size: 16px; margin: 0 0 8px; }
.foot-brand p { margin: 0 0 8px; }
.foot-h { font-size: 12px; text-transform: uppercase; letter-spacing: .08em; color: var(--eyebrow); margin: 0 0 8px; font-weight: 700; }
.foot-col ul { list-style: none; padding: 0; margin: 0; }
.foot-col li { margin: 0 0 6px; }
.foot-col a { color: var(--ink); text-decoration: none; }
.foot-col a:hover { text-decoration: underline; }
.foot-fine { margin-top: 24px; padding-top: 16px; border-top: 1px solid var(--line); font-size: 13px; }

@media (max-width: 480px) {
  .field { grid-template-columns: 1fr 8em; }
  .brand-sub { display: none; }
  .calc-nav { gap: 3px 4px; }
  .calc-nav a, .head-links a { padding: 5px 9px; font-size: 13px; }
}

/* Prose sections: how to use, worked example, FAQ */
.prose { margin-top: 24px; max-width: 75ch; }
.prose h2 { font-size: 22px; margin: 0 0 10px; }
.prose h3 { font-size: 16px; margin: 16px 0 4px; }
.prose p { margin: 0 0 10px; }
.prose ol { padding-left: 22px; margin: 0; }
.prose li { margin-bottom: 6px; }
#example { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px; }
#example p:last-child { margin-bottom: 0; }

/* Article pages: guides, about, contact, privacy, 404 */
main.article { display: grid; grid-template-columns: minmax(0, 1fr); gap: 0 48px; align-items: start; }
.article-head { grid-column: 1 / -1; }
.article-toc { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 14px 16px; font-size: 14px; margin-bottom: 16px; }
.article-toc h2 { font-size: 12px; text-transform: uppercase; letter-spacing: .08em; color: var(--eyebrow); font-weight: 700; margin: 0 0 8px; }
.article-toc ul { list-style: none; padding: 0; margin: 0; }
.article-toc li { margin: 0 0 6px; }
.article-toc a { color: var(--ink); text-decoration: none; }
.article-toc a:hover { text-decoration: underline; }
.article-body .prose { margin-top: 24px; max-width: none; }
.article-body .prose:first-child { margin-top: 8px; }
.article-side { display: flex; flex-direction: column; gap: 16px; margin-top: 24px; }
.side-card { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px 18px; }
.side-card h2 { font-size: 15px; margin: 0 0 8px; }
.side-card p { margin: 0 0 10px; font-size: 15px; color: var(--muted); }
.side-card ul { list-style: none; padding: 0; margin: 0; }
.side-card li { margin: 0 0 6px; font-size: 14px; }
.side-card .btn { margin-top: 4px; }
@media (min-width: 1100px) {
  main.article { grid-template-columns: minmax(0, 76ch) minmax(280px, 380px); }
  .article-toc { grid-column: 2; grid-row: 2; margin-bottom: 0; }
  .article-body { grid-column: 1; grid-row: 2 / span 2; }
  .article-side { grid-column: 2; grid-row: 3; margin-top: 16px; }
  .article-toc, .article-side { position: sticky; top: 16px; align-self: start; }
}
@media (min-width: 1500px) {
  main.article { grid-template-columns: minmax(240px, 1fr) minmax(0, 84ch) minmax(320px, 1fr); }
  .article-toc { grid-column: 1; grid-row: 2; }
  .article-body { grid-column: 2; grid-row: 2; }
  .article-side { grid-column: 3; grid-row: 2; margin-top: 0; }
}

/* Wide screens (1920x1080): form | results side by side, prose in a sensible grid */
@media (min-width: 1400px) {
  .calc { grid-template-columns: minmax(0, 1fr) minmax(0, 1.6fr); gap: 24px; }
  main:has(.calc) { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.6fr); gap: 0 24px; align-items: start; }
  main:has(.calc) > * { grid-column: 1 / -1; }
  main:has(.calc) > #how-to-use { grid-column: 1; max-width: none; }
  main:has(.calc) > #example { grid-column: 2; max-width: none; }
  main:has(.calc) > #faq { grid-column: 2; max-width: none; align-self: start; margin-top: 24px; }
  main:has(.calc) > #faq h3:first-of-type { margin-top: 0; }
  main:has(.calc) > .how { grid-column: 1; max-width: none; align-self: start; margin-top: 24px; }
  main:has(.calc) > .upsell, main:has(.calc) > .signup { grid-column: 1 / -1; }
}