/* Trefoil Guides: "field ledger" visual system.
   Warm paper, dark ink, one trefoil green. Serif headlines, sans body,
   monospace for every date, count and source detail. No external fonts. */

:root {
  --paper: #f5f1e8;
  --paper-2: #ece5d6;
  --card: #fbf9f4;
  --ink: #1c201b;
  --ink-2: #4b5148;
  --ink-3: #6b6f63;
  --rule: #d5cbb6;
  --rule-strong: #b9ad94;
  --green: #2d6a3e;
  --green-ink: #1e4a2b;
  --green-wash: #e3ecdf;
  --warn: #8a3f1c;
  --warn-wash: #f6e6da;

  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", Georgia, serif;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;

  --measure: 44rem;
  --gap: clamp(1rem, 2.5vw, 1.5rem);
  --radius: 6px;
  color-scheme: light;
}

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

html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; scroll-padding-top: 1rem; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 1.0625rem/1.65 var(--sans);
  overflow-wrap: break-word;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main { flex: 1 0 auto; }

img, svg { max-width: 100%; }

a { color: var(--green-ink); text-decoration-thickness: 1px; text-underline-offset: 0.18em; }
a:hover { color: var(--green); text-decoration-thickness: 2px; }
:focus-visible { outline: 3px solid var(--green); outline-offset: 2px; border-radius: 2px; }

.wrap { width: min(100% - 2 * var(--gap), 72rem); margin-inline: auto; }

.skip {
  position: absolute; left: 0.5rem; top: -3rem; z-index: 10;
  background: var(--ink); color: var(--paper); padding: 0.5rem 0.75rem; border-radius: var(--radius);
}
.skip:focus { top: 0.5rem; }

/* Header and footer ------------------------------------------------------ */

.site-header { border-bottom: 1px solid var(--rule); background: var(--paper); }
.header-row { display: flex; align-items: center; justify-content: space-between; gap: 1rem; min-height: 4rem; flex-wrap: wrap; padding-block: 0.5rem; }
.brand { display: inline-flex; align-items: center; gap: 0.55rem; color: var(--ink); text-decoration: none; font: 600 1.15rem/1 var(--serif); letter-spacing: 0.01em; }
.brand:hover { color: var(--ink); }
.mark { width: 1.6rem; height: 1.6rem; fill: var(--green); }
.mark .stem { stroke: var(--green); stroke-width: 2.4; stroke-linecap: round; fill: none; }
.site-header nav, .site-footer nav { display: flex; gap: 0.25rem 1.1rem; flex-wrap: wrap; }
.site-header nav a { color: var(--ink-2); text-decoration: none; font-size: 0.95rem; padding: 0.35rem 0; }
.site-header nav a:hover { color: var(--green-ink); text-decoration: underline; }

.site-footer { margin-top: 4rem; border-top: 1px solid var(--rule); background: var(--paper-2); color: var(--ink-2); font-size: 0.9rem; }
.footer-row { display: flex; justify-content: space-between; gap: 0.75rem 2rem; flex-wrap: wrap; padding-block: 1.5rem; }
.footer-row p { margin: 0; max-width: 38rem; }
.site-footer a { color: var(--ink-2); }

/* Shared type ----------------------------------------------------------- */

h1, h2, h3 { font-family: var(--serif); line-height: 1.2; color: var(--ink); text-wrap: balance; }
h1 { font-size: clamp(1.9rem, 1.3rem + 2.6vw, 3rem); font-weight: 600; letter-spacing: -0.01em; margin: 0.2rem 0 1rem; }
h2 { font-size: clamp(1.35rem, 1.1rem + 0.9vw, 1.7rem); font-weight: 600; margin: 2.75rem 0 0.75rem; }
h3 { font-size: 1.15rem; font-weight: 600; margin: 1.75rem 0 0.4rem; }
p, ul, ol { margin: 0 0 1rem; }
ul, ol { padding-left: 1.3rem; }
li + li { margin-top: 0.35rem; }
code { font: 0.9em var(--mono); background: var(--paper-2); padding: 0.05em 0.3em; border-radius: 3px; }
strong { font-weight: 650; }

.kicker { font: 600 0.78rem/1.3 var(--mono); letter-spacing: 0.08em; text-transform: uppercase; color: var(--green-ink); margin: 0; }

/* Stamps: the signature element. Every date on the site is a stamp. */
.stamps { display: flex; flex-wrap: wrap; gap: 0.5rem; margin: 0 0 0.5rem; }
.stamp {
  display: inline-flex; align-items: baseline; gap: 0.4rem;
  font: 500 0.8rem/1 var(--mono); color: var(--green-ink);
  border: 1.5px dashed color-mix(in srgb, var(--green) 70%, transparent);
  border-radius: 4px; padding: 0.4rem 0.55rem; background: color-mix(in srgb, var(--green-wash) 55%, transparent);
  white-space: nowrap;
}
.stamp-label { text-transform: uppercase; letter-spacing: 0.08em; font-size: 0.7rem; color: var(--ink-3); }

/* Home ------------------------------------------------------------------ */

.hero { padding-block: clamp(2.5rem, 6vw, 4.5rem) 1rem; max-width: 72rem; }
.hero h1 { max-width: 20ch; font-size: clamp(2.2rem, 1.4rem + 3.6vw, 3.75rem); }
.lede { font-size: clamp(1.1rem, 1rem + 0.4vw, 1.3rem); color: var(--ink-2); max-width: 40rem; }
.principles { list-style: none; padding: 0; margin: 2rem 0 0; display: grid; gap: 0.75rem; grid-template-columns: repeat(auto-fit, minmax(min(100%, 17rem), 1fr)); }
.principles li { margin: 0; padding: 0.9rem 1rem; border-top: 2px solid var(--ink); font-size: 0.97rem; color: var(--ink-2); }
.principles strong { display: block; color: var(--ink); font-family: var(--serif); font-size: 1.08rem; margin-bottom: 0.15rem; }

.guides h2 { margin-top: 3rem; padding-bottom: 0.6rem; border-bottom: 1px solid var(--rule-strong); }
.cards { list-style: none; padding: 0; margin: 1.25rem 0 0; display: grid; gap: 1rem; grid-template-columns: repeat(auto-fill, minmax(min(100%, 21rem), 1fr)); }
.cards li { margin: 0; }
.card a {
  display: flex; flex-direction: column; gap: 0.55rem; height: 100%;
  padding: 1.15rem 1.2rem 1.1rem; text-decoration: none; color: var(--ink);
  background: var(--card); border: 1px solid var(--rule); border-radius: var(--radius);
  box-shadow: inset 4px 0 0 transparent;
  transition: transform 160ms ease, box-shadow 160ms ease, border-color 160ms ease;
}
.card a:hover { transform: translateY(-2px); border-color: var(--rule-strong); box-shadow: inset 4px 0 0 var(--green), 0 6px 18px -12px rgb(28 32 27 / 0.45); color: var(--ink); }
.card-title { font: 600 1.25rem/1.25 var(--serif); text-wrap: balance; }
.card-desc { color: var(--ink-2); font-size: 0.96rem; flex: 1; }
.card-meta { display: flex; flex-wrap: wrap; align-items: center; gap: 0.5rem 0.75rem; margin-top: 0.3rem; }
.count { font: 0.78rem var(--mono); color: var(--ink-3); }

/* Guide ----------------------------------------------------------------- */

.guide-head { padding-block: clamp(1.5rem, 4vw, 2.75rem) 1.25rem; border-bottom: 1px solid var(--rule); }
.crumbs { font-size: 0.88rem; color: var(--ink-3); margin-bottom: 1rem; }
.crumbs a { color: var(--ink-2); }
.guide-head h1 { max-width: 28ch; }

.guide-grid { display: grid; gap: 2.5rem; grid-template-columns: minmax(0, 1fr); }
.guide-main { min-width: 0; max-width: var(--measure); }
.guide-main > section { scroll-margin-top: 1rem; }

.answer { margin: 2rem 0 0.5rem; padding: 1.1rem 1.25rem 0.3rem; background: var(--card); border: 1px solid var(--rule); border-left: 4px solid var(--green); border-radius: var(--radius); font-size: 1.08rem; }
.answer-label { font: 600 0.75rem/1 var(--mono); letter-spacing: 0.08em; text-transform: uppercase; color: var(--green-ink); margin: 0 0 0.6rem; }

.ledger h2 { margin-top: 2.25rem; }
.ledger-note { color: var(--ink-3); font-size: 0.92rem; margin-top: -0.25rem; }
.facts { margin: 0; border-top: 2px solid var(--ink); }
.fact { display: grid; grid-template-columns: minmax(0, 11rem) minmax(0, 1fr); gap: 0.25rem 1.25rem; padding: 0.75rem 0; border-bottom: 1px solid var(--rule); }
.fact dt { font: 600 0.78rem/1.5 var(--mono); letter-spacing: 0.05em; text-transform: uppercase; color: var(--ink-2); padding-top: 0.15rem; }
.fact dd { margin: 0; }
.fact-value { display: block; }
.fact-meta { display: block; margin-top: 0.2rem; font: 0.78rem/1.4 var(--mono); color: var(--ink-3); }

.cite { font: 600 0.78em var(--mono); text-decoration: none; color: var(--green); padding: 0 0.1em; white-space: nowrap; }
.cite:hover { text-decoration: underline; }

.table-wrap { overflow-x: auto; margin: 0 0 1.25rem; border: 1px solid var(--rule); border-radius: var(--radius); background: var(--card); }
table { border-collapse: collapse; width: 100%; font-size: 0.94rem; line-height: 1.45; }
th, td { text-align: left; vertical-align: top; padding: 0.6rem 0.75rem; border-bottom: 1px solid var(--rule); }
th { font: 600 0.74rem/1.3 var(--mono); letter-spacing: 0.05em; text-transform: uppercase; color: var(--ink-2); background: var(--paper-2); }
tbody tr:last-child td { border-bottom: 0; }

.qa h3 { margin-top: 1.4rem; }

.sources ol { padding-left: 1.6rem; }
.sources li { margin-bottom: 0.9rem; scroll-margin-top: 1rem; }
.sources li::marker { font: 600 0.85rem var(--mono); color: var(--green); }
.sources li:target { background: var(--green-wash); outline: 2px solid var(--green-wash); border-radius: 3px; }
.src-title { display: block; font-weight: 600; }
.src-meta, .src-url { display: block; font: 0.78rem/1.45 var(--mono); color: var(--ink-3); }
.src-url { overflow-wrap: anywhere; }
.method { margin-top: 1.5rem; padding-top: 1rem; border-top: 1px dashed var(--rule-strong); color: var(--ink-2); font-size: 0.93rem; }

.toc { font-size: 0.92rem; }
.toc-label { font: 600 0.75rem/1 var(--mono); letter-spacing: 0.08em; text-transform: uppercase; color: var(--ink-3); margin-bottom: 0.75rem; }
.toc ol { list-style: none; padding: 0; margin: 0; border-left: 1px solid var(--rule-strong); }
.toc li { margin: 0; }
.toc a { display: block; padding: 0.3rem 0 0.3rem 0.85rem; margin-left: -1px; border-left: 2px solid transparent; color: var(--ink-2); text-decoration: none; line-height: 1.35; }
.toc a:hover { color: var(--green-ink); border-left-color: var(--green); }

.guide-side { display: none; }

.related { margin-top: 3.5rem; padding-top: 0.5rem; border-top: 2px solid var(--ink); }
.related h2 { margin-top: 1rem; }
.related ul { list-style: none; padding: 0; display: grid; gap: 0.75rem; grid-template-columns: repeat(auto-fill, minmax(min(100%, 18rem), 1fr)); }
.related li { margin: 0; }
.related a { display: flex; flex-direction: column; gap: 0.3rem; padding: 0.9rem 1rem; border: 1px solid var(--rule); border-radius: var(--radius); background: var(--card); text-decoration: none; color: var(--ink); font: 600 1.05rem/1.3 var(--serif); }
.related a:hover { border-color: var(--green); color: var(--ink); }

/* Plain pages ----------------------------------------------------------- */

.prose-page { padding-top: clamp(1.75rem, 5vw, 3rem); }
.prose-page > * { max-width: var(--measure); }
.prose-page .stamps { margin-bottom: 1.5rem; }
.notice { padding: 0.8rem 1rem; background: var(--warn-wash); border-left: 4px solid var(--warn); border-radius: var(--radius); color: var(--ink); }
.notfound h1 { max-width: 18ch; }
.button { display: inline-block; padding: 0.7rem 1.1rem; background: var(--ink); color: var(--paper); text-decoration: none; border-radius: var(--radius); font-weight: 600; }
.button:hover { background: var(--green-ink); color: var(--paper); }

/* Responsive ------------------------------------------------------------ */

@media (min-width: 62rem) {
  .guide-grid { grid-template-columns: minmax(0, var(--measure)) 15rem; justify-content: space-between; }
  .guide-side { display: block; }
  .toc { position: sticky; top: 1.5rem; margin-top: 2rem; }
}

@media (max-width: 34rem) {
  body { font-size: 1rem; }
  .fact { grid-template-columns: minmax(0, 1fr); gap: 0.15rem; }
  .header-row { min-height: 3.5rem; }
  .site-header nav { gap: 0.25rem 0.9rem; }
  .answer { font-size: 1.02rem; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; animation: none !important; scroll-behavior: auto !important; }
  .card a:hover { transform: none; }
}

@media print {
  .site-header nav, .site-footer, .guide-side, .related, .skip { display: none; }
  body { background: #fff; }
}