:root {
  --bg: #fbfaf7;
  --surface: #ffffff;
  --surface-2: #f3f1ea;
  --ink: #18231f;
  --ink-2: #4a5852;
  --ink-3: #6f7c76;
  --line: #e2ded3;
  --accent: #1f5c4a;
  --accent-ink: #ffffff;
  --accent-soft: #e4efe9;
  --gold: #a7802f;
  --warn-bg: #fbf3e2;
  --warn-line: #e6cf9b;
  --radius: 10px;
  --wrap: 1120px;
  --measure: 70ch;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #111715; --surface: #172019; --surface-2: #1d2823; --ink: #e8eee9; --ink-2: #b4c0ba; --ink-3: #8c9a93;
    --line: #2b3832; --accent: #6fc2a3; --accent-ink: #0d1612; --accent-soft: #1d3329; --gold: #d3ad5e;
    --warn-bg: #2a2416; --warn-line: #5a4a26; color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #111715; --surface: #172019; --surface-2: #1d2823; --ink: #e8eee9; --ink-2: #b4c0ba; --ink-3: #8c9a93;
  --line: #2b3832; --accent: #6fc2a3; --accent-ink: #0d1612; --accent-soft: #1d3329; --gold: #d3ad5e;
  --warn-bg: #2a2416; --warn-line: #5a4a26; color-scheme: dark;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 400 17px/1.65 Inter, system-ui, -apple-system, "Segoe UI", sans-serif; }
img, svg { max-width: 100%; }
a { color: var(--accent); text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }
h1, h2, h3 { font-family: Fraunces, Georgia, serif; font-weight: 600; line-height: 1.2; letter-spacing: -0.01em; }
h1 { font-size: clamp(2rem, 4.5vw, 3rem); margin: 0.2em 0 0.4em; }
h2 { font-size: clamp(1.4rem, 2.6vw, 1.8rem); margin: 2em 0 0.6em; scroll-margin-top: 80px; }
h3 { font-size: 1.2rem; margin: 1.6em 0 0.5em; }
p, ul, ol { margin: 0 0 1em; }
li { margin-bottom: 0.35em; }
abbr { text-decoration: underline dotted; }
.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 16px; }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 16px; top: 8px; background: var(--surface); padding: 8px 12px; z-index: 10; }
.small { font-size: 0.9rem; color: var(--ink-2); }
.tiny { font-size: 0.78rem; color: var(--ink-3); margin: 0.6em 0 0; }
.eyebrow { text-transform: uppercase; letter-spacing: 0.12em; font-size: 0.75rem; font-weight: 600; color: var(--gold); margin: 0 0 0.4em; }
.meta { color: var(--ink-3); font-size: 0.88rem; }
.lede { font-size: 1.18rem; color: var(--ink-2); max-width: 62ch; }

/* header */
.site-header { position: sticky; top: 0; z-index: 5; background: color-mix(in srgb, var(--bg) 92%, transparent); backdrop-filter: blur(8px); border-bottom: 1px solid var(--line); }
.header-inner { display: flex; align-items: center; justify-content: space-between; min-height: 62px; gap: 16px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-family: Fraunces, Georgia, serif; font-weight: 600; font-size: 1.15rem; color: var(--ink); text-decoration: none; }
.brand-mark { width: 22px; height: 22px; border-radius: 50%; border: 2px solid var(--accent); position: relative; flex: none; }
.brand-mark::after { content: ""; position: absolute; inset: 4px; border-radius: 50%; background: var(--gold); }
.site-nav { display: flex; gap: 4px; }
.site-nav a { color: var(--ink-2); text-decoration: none; padding: 8px 12px; border-radius: 8px; font-size: 0.95rem; font-weight: 500; }
.site-nav a:hover, .site-nav a[aria-current] { background: var(--surface-2); color: var(--ink); }
.nav-toggle { display: none; background: none; border: 1px solid var(--line); border-radius: 8px; padding: 6px 12px; color: var(--ink); font: inherit; font-size: 0.9rem; }
@media (max-width: 760px) {
  .nav-toggle { display: block; }
  .site-nav { display: none; position: absolute; left: 0; right: 0; top: 62px; flex-direction: column; background: var(--bg); border-bottom: 1px solid var(--line); padding: 8px 16px 16px; }
  .site-nav.open { display: flex; }
}

/* layout */
.page { padding: 28px 0 64px; }
.article-grid { display: grid; grid-template-columns: minmax(0, 1fr) 300px; gap: 48px; align-items: start; }
.article-body { max-width: var(--measure); }
.sidebar { position: sticky; top: 84px; display: grid; gap: 20px; }
@media (max-width: 960px) { .article-grid { grid-template-columns: 1fr; } .sidebar { position: static; } }

.crumbs ol { list-style: none; display: flex; flex-wrap: wrap; gap: 6px; padding: 0; margin: 0 0 8px; font-size: 0.85rem; color: var(--ink-3); }
.crumbs li + li::before { content: "/"; margin-right: 6px; color: var(--line); }
.crumbs a { color: var(--ink-3); }

.toc { border: 1px solid var(--line); border-radius: var(--radius); padding: 16px 18px; background: var(--surface); font-size: 0.92rem; }
.toc-h { font-weight: 600; margin: 0 0 6px; }
.toc ol { margin: 0; padding-left: 18px; }
.toc a { color: var(--ink-2); text-decoration: none; }
.toc a:hover { color: var(--accent); }

.facts { border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); padding: 6px 18px; margin: 0; }
.facts div { display: grid; grid-template-columns: 9.5em 1fr; gap: 12px; padding: 10px 0; border-bottom: 1px solid var(--line); font-size: 0.93rem; }
.facts div:last-child { border-bottom: 0; }
.facts dt { color: var(--ink-3); }
.facts dd { margin: 0; font-weight: 500; overflow-wrap: anywhere; }
.aliases { color: var(--ink-3); font-size: 0.92rem; }

.notice { background: var(--warn-bg); border: 1px solid var(--warn-line); border-radius: var(--radius); padding: 12px 16px; font-size: 0.92rem; margin: 1.2em 0; }
.formula { font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace; font-size: 0.92rem; background: var(--surface-2); padding: 10px 14px; border-radius: 8px; overflow-x: auto; }

table { width: 100%; border-collapse: collapse; margin: 1em 0 1.4em; font-size: 0.93rem; display: block; overflow-x: auto; }
thead th { text-align: left; font-weight: 600; background: var(--surface-2); }
th, td { padding: 9px 12px; border-bottom: 1px solid var(--line); vertical-align: top; }
@media (min-width: 640px) { table { display: table; } }

.refs { font-size: 0.86rem; color: var(--ink-2); }
.refs li { margin-bottom: 0.6em; }

.faq details { border-bottom: 1px solid var(--line); padding: 4px 0; }
.faq summary { cursor: pointer; font-weight: 600; padding: 10px 0; list-style: none; position: relative; padding-right: 28px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; position: absolute; right: 4px; top: 8px; font-size: 1.3rem; color: var(--ink-3); }
.faq details[open] summary::after { content: "–"; }
.faq details div { color: var(--ink-2); }

.supplier-card { border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); padding: 18px; }
.supplier-title { font-family: Fraunces, Georgia, serif; font-size: 1.15rem; font-weight: 600; margin: 0 0 4px; }
.btn { display: inline-block; background: var(--accent); color: var(--accent-ink); padding: 10px 16px; border-radius: 8px; text-decoration: none; font-weight: 600; font-size: 0.95rem; margin-top: 6px; }
.btn:hover { filter: brightness(1.08); }
.btn.ghost { background: transparent; color: var(--accent); border: 1px solid var(--accent); }

.sub-nav { display: flex; flex-wrap: wrap; gap: 8px; margin: 8px 0 20px; }
.sub-nav a { border: 1px solid var(--line); border-radius: 999px; padding: 6px 14px; font-size: 0.9rem; text-decoration: none; color: var(--ink-2); background: var(--surface); }
.sub-nav a[aria-current] { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }

/* cards */
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 16px; }
.card { display: block; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); padding: 18px; text-decoration: none; color: var(--ink); transition: border-color .15s, transform .15s; }
.card:hover { border-color: var(--accent); transform: translateY(-1px); }
.card h3 { margin: 0 0 6px; font-size: 1.1rem; }
.card p { margin: 0; color: var(--ink-2); font-size: 0.92rem; }
.card .tag { display: inline-block; font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--gold); font-weight: 600; margin-bottom: 6px; }

/* home */
.hero { padding: 56px 0 40px; border-bottom: 1px solid var(--line); }
.hero h1 { max-width: 18ch; }
.search { display: flex; gap: 8px; max-width: 520px; margin-top: 20px; }
.search input { flex: 1; min-width: 0; font: inherit; padding: 12px 14px; border: 1px solid var(--line); border-radius: 8px; background: var(--surface); color: var(--ink); }
.section { padding: 40px 0 8px; }
.section > h2:first-child { margin-top: 0; }
.cat-list { columns: 2 260px; column-gap: 32px; }
.cat-list h3 { margin-top: 0; break-after: avoid; }
.cat-list ul { list-style: none; padding: 0; margin: 0 0 24px; break-inside: avoid; }
.strip { background: var(--surface-2); border-radius: var(--radius); padding: 20px 22px; margin: 32px 0; }

/* calculator */
.calc { border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); padding: 20px; margin: 1.6em 0; }
.calc h2 { margin-top: 0; }
.calc-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 14px; }
.calc label { display: grid; gap: 6px; font-size: 0.88rem; font-weight: 500; color: var(--ink-2); }
.calc input, .calc select { font: inherit; padding: 10px 12px; border: 1px solid var(--line); border-radius: 8px; background: var(--bg); color: var(--ink); width: 100%; min-width: 0; }
.split { display: flex; gap: 8px; }
.split input { flex: 1; }
.split select { width: auto; flex: none; padding-right: 28px; }
.presets button { font: inherit; font-size: 0.85rem; border: 1px solid var(--line); background: var(--bg); color: var(--ink); border-radius: 999px; padding: 4px 12px; cursor: pointer; }
.calc-out { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 12px; margin: 18px 0 10px; }
.calc-out > div { background: var(--surface-2); border-radius: 8px; padding: 12px; }
.calc-out .k { display: block; font-size: 0.78rem; color: var(--ink-3); }
.calc-out .v { font-weight: 600; font-size: 1.05rem; }
.calc-out .v.big { font-size: 1.5rem; color: var(--accent); }
.syringe .barrel { fill: var(--bg); stroke: var(--ink-3); }
.syringe .fill { fill: var(--accent); opacity: 0.75; transition: width .2s; }
.syringe .needle, .syringe .plunger { fill: var(--ink-3); }
.calc-warn { color: var(--gold); }

/* footer */
.site-footer { border-top: 1px solid var(--line); background: var(--surface); padding: 40px 0 20px; margin-top: 40px; }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1.2fr; gap: 32px; }
.footer-grid a { display: block; color: var(--ink-2); text-decoration: none; font-size: 0.92rem; margin-bottom: 6px; }
.footer-grid p a { display: inline; color: var(--accent); }
.footer-h { font-family: Inter, sans-serif; font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.1em; color: var(--ink-3); margin: 0 0 12px; }
.footer-brand { margin-bottom: 8px; }
.footer-base { border-top: 1px solid var(--line); margin-top: 28px; padding-top: 16px; }
@media (max-width: 860px) { .footer-grid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 520px) { .footer-grid { grid-template-columns: 1fr; } }