/* ==========================================================================
   SPR Solutions — design system
   Shared verbatim by the Next.js app and the static build.
   ========================================================================== */

:root {
  --ink:        #101820;
  --ink-2:      #1b2430;
  --paper:      #fbfaf7;
  --paper-2:    #f3f1ec;
  --rule:       #ddd8cd;
  --text:       #24303c;
  --text-soft:  #5d6b78;
  --accent:     #b8442c;   /* resonance red — used for the dip, and for citations */
  --accent-2:   #0d5c63;   /* plasmon teal */
  --gold:       #c9922e;
  --ok:         #2f7d4f;
  --warn:       #a8730b;
  --bad:        #a33121;
  --maxw:       none;
  --measure:    70ch;
  --serif:      "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", Georgia, serif;
  --sans:       ui-sans-serif, -apple-system, "Segoe UI", Inter, Roboto, sans-serif;
  --mono:       ui-monospace, "SF Mono", Menlo, Consolas, monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --ink: #e8e4dc; --ink-2: #cfc9bd;
    --paper: #14181d; --paper-2: #1b2027;
    --rule: #2e363f; --text: #d7d3ca; --text-soft: #9aa4ae;
    --accent: #e8735a; --accent-2: #4bb8be; --gold: #e0b45c;
    --ok: #63bd85; --warn: #d9a441; --bad: #e2705c;
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 5rem; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--text);
  font: 400 17px/1.68 var(--serif);
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent-2); text-decoration-thickness: 1px; text-underline-offset: 2px; }
a:hover { color: var(--accent); }

code { font: 500 0.88em var(--mono); background: var(--paper-2); padding: 0.1em 0.35em; border-radius: 3px; }

/* ── shell ────────────────────────────────────────────────────────────── */

.topbar {
  position: sticky; top: 0; z-index: 50;
  display: flex; align-items: center; gap: 1.25rem;
  padding: 0.7rem 1.5rem;
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--rule);
  font-family: var(--sans);
}
.brand { display: flex; align-items: baseline; gap: 0.5rem; font-weight: 700; letter-spacing: -0.02em; color: var(--ink); text-decoration: none; font-size: 1.05rem; }
.brand .dot { width: 9px; height: 9px; border-radius: 50%; background: var(--accent); display: inline-block; }
.brand .tld { color: var(--text-soft); font-weight: 500; }
.topnav { display: flex; gap: 1.1rem; margin-left: auto; font-size: 0.88rem; flex-wrap: wrap; }
.topnav a { color: var(--text-soft); text-decoration: none; }
.topnav a:hover, .topnav a.on { color: var(--accent); }

.shell { display: grid; grid-template-columns: 270px minmax(0,1fr); gap: 0; align-items: start; }
@media (max-width: 1000px) { .shell { grid-template-columns: 1fr; } .sidebar { display: none; } }

.sidebar {
  position: sticky; top: 3.2rem; max-height: calc(100vh - 3.2rem); overflow-y: auto;
  padding: 1.6rem 1rem 4rem 1.5rem; border-right: 1px solid var(--rule);
  font-family: var(--sans); font-size: 0.86rem;
}
.sidebar .part { margin: 1.4rem 0 0.4rem; font-size: 0.7rem; letter-spacing: 0.09em; text-transform: uppercase; color: var(--text-soft); font-weight: 700; }
.sidebar a { display: block; padding: 0.28rem 0.5rem; border-radius: 5px; color: var(--text); text-decoration: none; line-height: 1.35; }
.sidebar a:hover { background: var(--paper-2); }
.sidebar a.on { background: color-mix(in srgb, var(--accent) 12%, transparent); color: var(--accent); font-weight: 600; }
.sidebar .cn { color: var(--text-soft); font-variant-numeric: tabular-nums; margin-right: 0.4rem; }

main { padding: 2.2rem clamp(1rem, 4vw, 3.5rem) 6rem; min-width: 0; }
.wrap { max-width: 1180px; margin: 0 auto; }

/* ── chapter typography ───────────────────────────────────────────────── */

.ch-head { border-bottom: 2px solid var(--ink); padding-bottom: 1.1rem; margin-bottom: 2rem; }
.ch-kicker { font-family: var(--sans); font-size: 0.72rem; letter-spacing: 0.11em; text-transform: uppercase; color: var(--accent); font-weight: 700; }
h1 { font-size: clamp(1.9rem, 3.6vw, 2.7rem); line-height: 1.12; margin: 0.4rem 0 0.5rem; letter-spacing: -0.02em; color: var(--ink); font-weight: 600; }
.ch-sub { font-size: 1.12rem; color: var(--text-soft); font-style: italic; margin: 0; max-width: var(--measure); }
.ch-meta { font-family: var(--sans); font-size: 0.78rem; color: var(--text-soft); margin-top: 0.9rem; display: flex; gap: 1.2rem; flex-wrap: wrap; }

h2 { font-size: 1.6rem; margin: 3rem 0 0.9rem; letter-spacing: -0.015em; color: var(--ink); font-weight: 600; scroll-margin-top: 5rem; }
h2 .sn { color: var(--accent); font-family: var(--sans); font-size: 0.85rem; font-weight: 700; display: block; margin-bottom: 0.15rem; letter-spacing: 0.06em; }
h4 { font-size: 1.06rem; margin: 1.8rem 0 0.4rem; color: var(--ink); font-weight: 600; }

p { margin: 0 0 1.05rem; max-width: var(--measure); }
p.lead { font-size: 1.19rem; line-height: 1.6; color: var(--ink-2); border-left: 3px solid var(--accent); padding-left: 1.1rem; }
ul, ol { max-width: var(--measure); padding-left: 1.3rem; margin: 0 0 1.15rem; }
li { margin-bottom: 0.5rem; }

/* ── citations & glossary ─────────────────────────────────────────────── */

/* Inline author–year citations. Sized down slightly and set in the sans face so
   they sit in the text without breaking the reading rhythm. */
.cites { font-family: var(--sans); font-size: 0.82em; color: var(--text-soft); white-space: normal; }
a.cite {
  color: var(--accent-2); text-decoration: none; font-weight: 600;
  border-bottom: 1px solid color-mix(in srgb, var(--accent-2) 35%, transparent);
}
a.cite:hover { color: var(--accent); border-bottom-color: var(--accent); background: color-mix(in srgb, var(--accent) 8%, transparent); }
a.cite-review { font-style: italic; }
a.cite-missing { background: var(--bad); color: #fff; padding: 0 4px; border-radius: 3px; border: none; }

.ref { grid-template-columns: 12.5rem 1fr; }
.refkey { font-family: var(--sans); font-weight: 700; color: var(--accent-2); font-size: 0.86rem; line-height: 1.5; }
@media (max-width: 640px) { .ref { grid-template-columns: 1fr; } .refkey { color: var(--accent); } }

a.gloss, span.gloss {
  color: inherit; text-decoration: none;
  border-bottom: 1px dotted var(--accent-2); cursor: help;
}
a.gloss:hover { color: var(--accent-2); border-bottom-style: solid; }
.gloss-missing { background: var(--bad); color: #fff; }

/* ── equations ────────────────────────────────────────────────────────── */

.eq {
  margin: 1.6rem 0; padding: 1.1rem 1.3rem;
  background: var(--paper-2); border-radius: 8px; border: 1px solid var(--rule);
  max-width: calc(var(--measure) + 6rem);
}
.eq-body { display: flex; align-items: center; gap: 1rem; }
.eq-math {
  flex: 1; text-align: center; font-family: var(--serif); font-size: 1.16rem;
  overflow-x: auto; padding: 0.4rem 0; color: var(--ink);
}
.eq-math i { font-style: italic; }
.eq-num { font-family: var(--sans); font-size: 0.82rem; color: var(--text-soft); font-variant-numeric: tabular-nums; }
.where { margin-top: 0.9rem; border-top: 1px solid var(--rule); padding-top: 0.7rem; }
.where-h { font-family: var(--sans); font-size: 0.68rem; text-transform: uppercase; letter-spacing: 0.1em; color: var(--text-soft); margin-bottom: 0.4rem; font-weight: 700; }
.wrow { display: grid; grid-template-columns: minmax(52px, max-content) 1fr; gap: 0.9rem; font-size: 0.9rem; margin-bottom: 0.22rem; align-items: baseline; }
.wsym { font-family: var(--serif); font-style: italic; color: var(--accent-2); text-align: right; font-weight: 600; }
.wmean { color: var(--text-soft); }
.eq figcaption, .tbl figcaption, .figw figcaption {
  margin-top: 0.75rem; font-size: 0.88rem; color: var(--text-soft); line-height: 1.5; font-family: var(--sans);
}

/* ── callout boxes ────────────────────────────────────────────────────── */

.box, .worked {
  margin: 1.7rem 0; padding: 1.1rem 1.3rem; border-radius: 8px;
  border: 1px solid var(--rule); border-left: 4px solid var(--text-soft);
  background: var(--paper-2); max-width: calc(var(--measure) + 4rem);
}
.box-h, .worked-h { font-weight: 700; color: var(--ink); margin-bottom: 0.55rem; font-size: 1rem; }
.box-tag {
  display: inline-block; font-family: var(--sans); font-size: 0.63rem; letter-spacing: 0.1em;
  text-transform: uppercase; padding: 0.16rem 0.45rem; border-radius: 3px; margin-right: 0.6rem;
  background: var(--text-soft); color: var(--paper); vertical-align: 0.12em; font-weight: 700;
}
.box-b > *:last-child { margin-bottom: 0; }
.box-b p { max-width: none; font-size: 0.97rem; }
.box-key   { border-left-color: var(--accent-2); }  .box-key   .box-tag { background: var(--accent-2); }
.box-why   { border-left-color: var(--gold); }      .box-why   .box-tag { background: var(--gold); }
.box-warn  { border-left-color: var(--bad); }       .box-warn  .box-tag { background: var(--bad); }
.box-math  { border-left-color: #6a5acd; }          .box-math  .box-tag { background: #6a5acd; }
.box-bench { border-left-color: var(--ok); }        .box-bench .box-tag { background: var(--ok); }
.box-myth  { border-left-color: var(--accent); }    .box-myth  .box-tag { background: var(--accent); }
.worked    { border-left-color: var(--accent-2); background: color-mix(in srgb, var(--accent-2) 6%, var(--paper)); }
.worked .box-tag { background: var(--accent-2); }

/* ── tables ───────────────────────────────────────────────────────────── */

.tbl { margin: 1.8rem 0; overflow-x: auto; }
.tbl table { border-collapse: collapse; width: 100%; font-size: 0.93rem; font-family: var(--sans); }
.tbl th {
  text-align: left; padding: 0.6rem 0.8rem; border-bottom: 2px solid var(--ink);
  font-size: 0.74rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--ink); font-weight: 700;
}
.tbl td { padding: 0.6rem 0.8rem; border-bottom: 1px solid var(--rule); vertical-align: top; }
.tbl tr:hover td { background: var(--paper-2); }

/* ── figures / widgets ────────────────────────────────────────────────── */

.figw { margin: 2rem 0; }
.widget-mount {
  border: 1px solid var(--rule); border-radius: 10px; background: var(--paper-2);
  padding: 1rem; overflow: hidden;
}
.wtitle { font-family: var(--sans); font-size: 0.78rem; font-weight: 700; letter-spacing: 0.06em; text-transform: uppercase; color: var(--text-soft); margin-bottom: 0.7rem; }
.controls { display: flex; flex-wrap: wrap; gap: 0.9rem 1.4rem; margin-top: 0.9rem; font-family: var(--sans); font-size: 0.82rem; }
.ctrl { display: flex; flex-direction: column; gap: 0.15rem; min-width: 150px; flex: 1 1 150px; }
.ctrl label { color: var(--text-soft); display: flex; justify-content: space-between; gap: 0.6rem; }
.ctrl label b { color: var(--accent-2); font-variant-numeric: tabular-nums; font-weight: 700; }
.ctrl input[type=range] { width: 100%; accent-color: var(--accent); }
.ctrl select, .ctrl input[type=number] {
  font: inherit; padding: 0.25rem 0.4rem; border: 1px solid var(--rule);
  border-radius: 4px; background: var(--paper); color: var(--text);
}
.readout { display: flex; flex-wrap: wrap; gap: 1.4rem; margin-top: 0.8rem; font-family: var(--sans); font-size: 0.84rem; }
.readout div { color: var(--text-soft); }
.readout b { display: block; color: var(--ink); font-size: 1.05rem; font-variant-numeric: tabular-nums; }
.btnrow { display: flex; gap: 0.5rem; flex-wrap: wrap; margin-top: 0.8rem; }
button.b {
  font: 600 0.82rem var(--sans); padding: 0.4rem 0.85rem; border-radius: 6px;
  border: 1px solid var(--rule); background: var(--paper); color: var(--text); cursor: pointer;
}
button.b:hover { border-color: var(--accent); color: var(--accent); }
button.b.pri { background: var(--accent); color: #fff; border-color: var(--accent); }
button.b.pri:hover { filter: brightness(1.08); color: #fff; }

/* ── references ───────────────────────────────────────────────────────── */

.refs { list-style: none; padding: 0; margin: 1rem 0 0; max-width: none; font-family: var(--sans); font-size: 0.9rem; }
.ref { display: grid; grid-template-columns: 2.2rem 1fr; gap: 0.4rem; padding: 0.65rem 0; border-bottom: 1px solid var(--rule); }
.ref:target { background: color-mix(in srgb, var(--accent) 9%, transparent); border-radius: 6px; padding-left: 0.5rem; }
.ref-broken { background: color-mix(in srgb, var(--bad) 15%, transparent); }
.doi { font-family: var(--mono); font-size: 0.82em; }
.vbadge {
  display: inline-block; font-size: 0.62rem; letter-spacing: 0.06em; text-transform: uppercase;
  padding: 0.1rem 0.4rem; border-radius: 3px; font-weight: 700; margin-left: 0.35rem; cursor: help; vertical-align: 0.08em;
}
.v-ok   { background: color-mix(in srgb, var(--ok) 20%, transparent);   color: var(--ok); }
.v-warn { background: color-mix(in srgb, var(--warn) 20%, transparent); color: var(--warn); }
.v-fix  { background: color-mix(in srgb, var(--accent) 20%, transparent); color: var(--accent); }
.kind { font-size: 0.62rem; text-transform: uppercase; letter-spacing: 0.06em; padding: 0.1rem 0.4rem; border-radius: 3px; background: var(--rule); color: var(--text-soft); margin-left: 0.3rem; font-weight: 700; }
.erratum, .refnote { font-size: 0.86rem; color: var(--text-soft); margin-top: 0.3rem; line-height: 1.45; }
.erratum { border-left: 2px solid var(--accent); padding-left: 0.6rem; }

/* ── quiz ─────────────────────────────────────────────────────────────── */

.quiz {
  margin: 2rem 0; border: 1px solid var(--rule); border-radius: 10px;
  background: var(--paper-2); padding: 1.2rem 1.35rem; max-width: calc(var(--measure) + 4rem);
}
.quiz-h { display: flex; align-items: baseline; gap: 0.7rem; font-family: var(--sans); margin-bottom: 0.9rem; }
.quiz-h strong { font-size: 1.05rem; color: var(--ink); }
.quiz-h span { font-size: 0.78rem; color: var(--text-soft); margin-left: auto; font-variant-numeric: tabular-nums; }
.q-stem { font-weight: 600; color: var(--ink); margin-bottom: 0.8rem; }
.q-opts { display: flex; flex-direction: column; gap: 0.45rem; }
.q-opt {
  text-align: left; font: 400 0.95rem/1.45 var(--serif); padding: 0.6rem 0.85rem;
  border: 1px solid var(--rule); border-radius: 7px; background: var(--paper);
  color: var(--text); cursor: pointer; display: flex; gap: 0.7rem; align-items: flex-start;
}
.q-opt:hover:not(:disabled) { border-color: var(--accent-2); }
.q-opt .k { font-family: var(--sans); font-weight: 700; color: var(--text-soft); flex: none; }
.q-opt.right { border-color: var(--ok); background: color-mix(in srgb, var(--ok) 12%, var(--paper)); }
.q-opt.wrong { border-color: var(--bad); background: color-mix(in srgb, var(--bad) 12%, var(--paper)); }
.q-opt.right .k { color: var(--ok); } .q-opt.wrong .k { color: var(--bad); }
.q-exp {
  margin-top: 0.9rem; padding: 0.8rem 1rem; border-radius: 7px; font-size: 0.93rem;
  background: var(--paper); border-left: 3px solid var(--accent-2); line-height: 1.55;
}
.q-exp b { color: var(--ink); }
.q-nav { display: flex; gap: 0.6rem; margin-top: 1rem; align-items: center; }
.q-score { margin-left: auto; font-family: var(--sans); font-size: 0.85rem; color: var(--text-soft); }
.q-bar { height: 4px; background: var(--rule); border-radius: 2px; overflow: hidden; margin-bottom: 0.9rem; }
.q-bar i { display: block; height: 100%; background: var(--accent); transition: width 0.25s; }

/* ── home / index pages ───────────────────────────────────────────────── */

.hero { padding: 3.5rem 0 2.5rem; border-bottom: 1px solid var(--rule); }
.hero h1 { font-size: clamp(2.2rem, 5vw, 3.6rem); max-width: 20ch; }
.hero p { font-size: 1.2rem; max-width: 62ch; color: var(--text-soft); }
.stats { display: flex; gap: 2.5rem; flex-wrap: wrap; margin-top: 2rem; font-family: var(--sans); }
.stats div { }
.stats b { display: block; font-size: 1.9rem; color: var(--accent); font-variant-numeric: tabular-nums; line-height: 1.1; }
.stats span { font-size: 0.8rem; color: var(--text-soft); text-transform: uppercase; letter-spacing: 0.07em; }

.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 1rem; margin: 1.4rem 0 2.5rem; }
.card {
  display: block; padding: 1.1rem 1.2rem; border: 1px solid var(--rule); border-radius: 10px;
  background: var(--paper-2); text-decoration: none; color: inherit; transition: border-color 0.15s, transform 0.15s;
}
.card:hover { border-color: var(--accent); transform: translateY(-2px); }
.card .cnum { font-family: var(--sans); font-size: 0.7rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--accent); font-weight: 700; }
.card h3 { margin: 0.3rem 0 0.35rem; font-size: 1.1rem; color: var(--ink); font-weight: 600; line-height: 1.25; }
.card p { font-size: 0.9rem; color: var(--text-soft); margin: 0; max-width: none; }
.card .cmeta { font-family: var(--sans); font-size: 0.74rem; color: var(--text-soft); margin-top: 0.6rem; }

.note {
  border: 1px dashed var(--rule); border-radius: 8px; padding: 1rem 1.2rem; margin: 1.5rem 0;
  background: var(--paper-2); font-size: 0.93rem;
}
.note p { max-width: none; }
.note p:last-child { margin-bottom: 0; }

/* ── literature feed ──────────────────────────────────────────────────── */

.lit-controls { display: flex; gap: 0.8rem; flex-wrap: wrap; align-items: flex-end; margin: 1.5rem 0; font-family: var(--sans); }
.lit-controls input[type=text], .lit-controls select {
  font: inherit; font-size: 0.9rem; padding: 0.5rem 0.7rem; border: 1px solid var(--rule);
  border-radius: 6px; background: var(--paper); color: var(--text);
}
.lit-controls input[type=text] { min-width: 280px; flex: 1 1 280px; }
.paper { border-bottom: 1px solid var(--rule); padding: 1.1rem 0; }
.paper h3 { margin: 0 0 0.3rem; font-size: 1.06rem; line-height: 1.35; font-weight: 600; }
.paper h3 a { color: var(--ink); text-decoration: none; }
.paper h3 a:hover { color: var(--accent); }
.paper .pmeta { font-family: var(--sans); font-size: 0.82rem; color: var(--text-soft); display: flex; gap: 0.8rem; flex-wrap: wrap; margin-bottom: 0.45rem; }
.paper .pmeta .j { color: var(--accent-2); font-weight: 600; }
.paper .pabs { font-size: 0.93rem; color: var(--text-soft); line-height: 1.55; max-width: 78ch; }
.tagrow { display: flex; gap: 0.35rem; flex-wrap: wrap; margin-top: 0.5rem; }
.tag { font-family: var(--sans); font-size: 0.68rem; padding: 0.13rem 0.45rem; border-radius: 3px; background: var(--paper-2); border: 1px solid var(--rule); color: var(--text-soft); }
.tag.oa { color: var(--ok); border-color: color-mix(in srgb, var(--ok) 40%, transparent); }
.spinner { text-align: center; padding: 3rem 0; color: var(--text-soft); font-family: var(--sans); }

/* ── misc ─────────────────────────────────────────────────────────────── */

.pager { display: flex; justify-content: space-between; gap: 1rem; margin-top: 3.5rem; padding-top: 1.5rem; border-top: 1px solid var(--rule); font-family: var(--sans); }
.pager a { display: block; max-width: 45%; text-decoration: none; color: var(--text-soft); font-size: 0.85rem; }
.pager a b { display: block; color: var(--ink); font-size: 1rem; margin-top: 0.15rem; }
.pager a:hover b { color: var(--accent); }
.pager .nx { text-align: right; margin-left: auto; }

footer.site { border-top: 1px solid var(--rule); padding: 2rem clamp(1rem,4vw,3.5rem); font-family: var(--sans); font-size: 0.82rem; color: var(--text-soft); }
footer.site p { max-width: 80ch; }

.sronly { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); }
h2 a.anchor { opacity: 0; color: var(--text-soft); text-decoration: none; font-size: 0.7em; margin-left: 0.4rem; }
h2:hover a.anchor { opacity: 1; }

@media print {
  .sidebar, .topbar, .quiz-mount, .btnrow { display: none; }
  body { background: #fff; color: #000; }
}

/* ══════════════════════════════════════════════════════════════════════════
   Home page, navigation chrome and accessibility affordances
   ══════════════════════════════════════════════════════════════════════════ */

.skip {
  position: absolute; left: -9999px; top: 0; z-index: 100;
  background: var(--accent); color: #fff; padding: 0.6rem 1rem; border-radius: 0 0 6px 0;
  font: 600 0.9rem var(--sans); text-decoration: none;
}
.skip:focus { left: 0; color: #fff; }

.crumbs {
  font-family: var(--sans); font-size: 0.8rem; color: var(--text-soft);
  margin-bottom: 1.2rem; display: flex; gap: 0.45rem; flex-wrap: wrap;
}
.crumbs a { color: var(--text-soft); text-decoration: none; }
.crumbs a:hover { color: var(--accent); text-decoration: underline; }

/* ── hero ─────────────────────────────────────────────────────────────── */

.hero { padding: 3rem 0 2.6rem; border-bottom: 1px solid var(--rule); }
.hero h1 { font-size: clamp(2.1rem, 5vw, 3.5rem); max-width: 18ch; margin-bottom: 1.1rem; }
.hero p { max-width: 60ch; color: var(--text-soft); font-size: 1.05rem; }
.hero-lead {
  font-size: 1.28rem !important; line-height: 1.55; color: var(--ink-2) !important;
  max-width: 58ch; margin-bottom: 1rem;
}
.hero-cta { display: flex; gap: 0.8rem; flex-wrap: wrap; margin-top: 1.9rem; }

.btn {
  display: inline-block; font: 600 0.95rem var(--sans); padding: 0.7rem 1.3rem;
  border-radius: 8px; border: 1px solid var(--rule); background: var(--paper-2);
  color: var(--text); text-decoration: none; transition: transform .12s, border-color .12s;
}
.btn:hover { transform: translateY(-1px); border-color: var(--accent); color: var(--accent); }
.btn-pri { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn-pri:hover { color: #fff; filter: brightness(1.07); }

.whatis { padding: 2.2rem 0 0; }
.whatis .lead { border-left-color: var(--accent-2); }

section { scroll-margin-top: 5rem; }

/* ── entry-path cards ─────────────────────────────────────────────────── */

.card-entry { border-left: 4px solid var(--accent-2); }
.card-entry .cnum { color: var(--accent-2); }
.card h3 { margin-top: 0.35rem; }

/* ── FAQ ──────────────────────────────────────────────────────────────── */

.faq { max-width: calc(var(--measure) + 6rem); }
.faq details {
  border: 1px solid var(--rule); border-radius: 8px; margin-bottom: 0.6rem;
  background: var(--paper-2); overflow: hidden;
}
.faq summary {
  cursor: pointer; padding: 0.85rem 1.1rem; font: 600 1rem var(--sans); color: var(--ink);
  list-style: none; display: flex; justify-content: space-between; gap: 1rem; align-items: center;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: '+'; color: var(--accent); font-size: 1.3rem; line-height: 1; flex: none; }
.faq details[open] summary::after { content: '−'; }
.faq summary:hover { color: var(--accent); }
.faq details p {
  margin: 0; padding: 0 1.1rem 1.1rem; color: var(--text-soft); font-size: 0.98rem;
  max-width: none; line-height: 1.65;
}

/* ── footer ───────────────────────────────────────────────────────────── */

.footcols {
  display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 2.5rem;
  max-width: 1180px; margin: 0 auto 1.8rem;
}
@media (max-width: 700px) { .footcols { grid-template-columns: 1fr; gap: 1.6rem; } }
.footcols b { display: block; color: var(--ink); margin-bottom: 0.6rem; font-size: 0.95rem; }
.footcols a { display: block; color: var(--text-soft); text-decoration: none; padding: 0.15rem 0; font-size: 0.86rem; }
.footcols a:hover { color: var(--accent); }
.footcols p { max-width: 46ch; margin: 0; font-size: 0.86rem; }
.footnote { max-width: 1180px; margin: 0 auto; padding-top: 1.4rem; border-top: 1px solid var(--rule); font-size: 0.8rem; }

/* ── cross-references ─────────────────────────────────────────────────── */

a.xref { color: var(--accent-2); text-decoration: none; border-bottom: 1px solid color-mix(in srgb, var(--accent-2) 40%, transparent); }
a.xref:hover { color: var(--accent); border-bottom-color: var(--accent); }