/* ==========================================================================
   Quantitative Markets Research Lab — shared stylesheet
   Palette: warm paper / ink / oxblood accent
   Type: Newsreader (serif display + prose), IBM Plex Mono (UI + data)
   ========================================================================== */

:root {
  --paper:      #f7f4ee;
  --paper-deep: #efeae0;
  --ink:        #1c1a17;
  --ink-soft:   #46423c;
  --muted:      #6d675e;
  --faint:      #9a938a;
  --rule:       #ddd6c8;
  --rule-soft:  #e7e1d4;
  --accent:     #8a3033;   /* oxblood */
  --accent-dim: #a86063;
  --slate:      #3e5c76;   /* chart secondary */
  --ochre:      #a07c33;
  --moss:       #5c6e4e;
  --plum:       #6b4a6e;
  --serif: 'Newsreader', 'Iowan Old Style', Georgia, serif;
  --mono:  'IBM Plex Mono', 'SF Mono', Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--serif);
  font-size: 18px;
  line-height: 1.62;
  font-feature-settings: "liga" 1;
  text-rendering: optimizeLegibility;
}

/* ---------- layout ---------- */

.wrap {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 28px;
}

.narrow { max-width: 760px; }

main { padding-bottom: 5rem; }

/* ---------- header / nav ---------- */

.site-header {
  border-bottom: 1px solid var(--rule);
  padding: 1.5rem 0 1.1rem;
}

.site-header .wrap {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.75rem 2rem;
}

.wordmark {
  font-family: var(--serif);
  font-size: 1.18rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--ink);
  text-decoration: none;
}
.wordmark .tail { color: var(--muted); font-weight: 400; font-style: italic; }

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 1.15rem;
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.site-nav a {
  color: var(--muted);
  text-decoration: none;
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
}
.site-nav a:hover { color: var(--ink); }
.site-nav a[aria-current="page"] {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* ---------- footer ---------- */

.site-footer {
  border-top: 1px solid var(--rule);
  margin-top: 4rem;
  padding: 1.6rem 0 2.4rem;
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.05em;
  color: var(--faint);
}
.site-footer .wrap {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.5rem 2rem;
}
.site-footer a { color: var(--muted); text-decoration: none; border-bottom: 1px solid var(--rule); }
.site-footer a:hover { color: var(--accent); }

/* ---------- typography ---------- */

h1, h2, h3 {
  font-family: var(--serif);
  font-weight: 500;
  line-height: 1.18;
  color: var(--ink);
  margin: 0 0 0.6em;
}

h1 { font-size: 2.5rem;  letter-spacing: -0.012em; }
h2 { font-size: 1.62rem; letter-spacing: -0.008em; margin-top: 0; }
h3 { font-size: 1.18rem; font-weight: 600; }

p { margin: 0 0 1.1em; }
p.lede {
  font-size: 1.22rem;
  line-height: 1.55;
  color: var(--ink-soft);
}

a { color: var(--accent); }
a:hover { color: var(--ink); }

strong { font-weight: 600; }
em { font-style: italic; }

hr {
  border: none;
  border-top: 1px solid var(--rule);
  margin: 3rem 0;
}

/* kicker: small-caps section label */
.kicker {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 0.9rem;
}
.kicker::before {
  content: "";
  display: inline-block;
  width: 1.6rem;
  height: 1px;
  background: var(--accent);
  vertical-align: middle;
  margin-right: 0.65rem;
}

.section {
  padding-top: 3.2rem;
}
.section + .section {
  margin-top: 3.2rem;
  border-top: 1px solid var(--rule);
}

.page-head {
  padding: 3.4rem 0 2.4rem;
  border-bottom: 1px solid var(--rule);
  margin-bottom: 0.5rem;
}
.page-head p.lede { max-width: 46em; margin-bottom: 0; }

/* ---------- home ---------- */

.hero { padding: 4.5rem 0 3.4rem; }
.hero h1 { max-width: 15em; }
.hero .lede { max-width: 36em; }

.thesis {
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
  padding: 2.4rem 0;
  margin: 2.5rem 0;
}
.thesis blockquote {
  margin: 0;
  font-size: 1.45rem;
  line-height: 1.45;
  font-style: italic;
  color: var(--ink-soft);
  max-width: 30em;
}
.thesis blockquote .plain { font-style: normal; }

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1px;
  background: var(--rule);
  border: 1px solid var(--rule);
  margin-top: 2rem;
}

.card {
  background: var(--paper);
  padding: 1.6rem 1.5rem 1.5rem;
  text-decoration: none;
  color: var(--ink);
  display: block;
  transition: background 120ms ease;
}
.card:hover { background: var(--paper-deep); color: var(--ink); }
.card .card-no {
  font-family: var(--mono);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  color: var(--faint);
  display: block;
  margin-bottom: 0.8rem;
}
.card h3 { margin-bottom: 0.45rem; }
.card p { font-size: 0.95rem; color: var(--muted); margin: 0; line-height: 1.5; }
.card:hover h3 { color: var(--accent); }

/* ---------- two-column tool layout ---------- */

.tool-grid {
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: 2.6rem;
  align-items: start;
  margin-top: 2rem;
}
@media (max-width: 880px) {
  .tool-grid { grid-template-columns: 1fr; }
}

.prose-col { max-width: 46em; }

/* ---------- controls ---------- */

.panel {
  border: 1px solid var(--rule);
  background: var(--paper);
  padding: 1.3rem 1.3rem 1.4rem;
}
.panel + .panel { margin-top: 1.2rem; }
.panel h3 {
  font-family: var(--mono);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 1.1rem;
}

.ctrl { margin-bottom: 0.95rem; }
.ctrl:last-child { margin-bottom: 0; }

.ctrl label {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.03em;
  color: var(--ink-soft);
  margin-bottom: 0.3rem;
}
.ctrl label .val {
  color: var(--accent);
  font-weight: 500;
}

input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 2px;
  background: var(--rule);
  outline: none;
  margin: 0.4rem 0 0.1rem;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 13px; height: 13px;
  border-radius: 50%;
  background: var(--paper);
  border: 1.5px solid var(--accent);
  cursor: pointer;
}
input[type="range"]::-moz-range-thumb {
  width: 11px; height: 11px;
  border-radius: 50%;
  background: var(--paper);
  border: 1.5px solid var(--accent);
  cursor: pointer;
}

select, input[type="number"] {
  font-family: var(--mono);
  font-size: 0.8rem;
  color: var(--ink);
  background: var(--paper);
  border: 1px solid var(--rule);
  padding: 0.4rem 0.55rem;
  width: 100%;
}
select:focus, input[type="number"]:focus { outline: 1px solid var(--accent-dim); }

/* segmented toggle */
.seg {
  display: inline-flex;
  border: 1px solid var(--rule);
}
.seg button {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  background: var(--paper);
  color: var(--muted);
  border: none;
  padding: 0.45rem 0.95rem;
  cursor: pointer;
}
.seg button + button { border-left: 1px solid var(--rule); }
.seg button.active {
  background: var(--ink);
  color: var(--paper);
}

.btn {
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  background: var(--ink);
  color: var(--paper);
  border: 1px solid var(--ink);
  padding: 0.6rem 1.4rem;
  cursor: pointer;
}
.btn:hover { background: var(--accent); border-color: var(--accent); }

/* checkbox rows */
.check-row {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  font-family: var(--mono);
  font-size: 0.76rem;
  color: var(--ink-soft);
  padding: 0.28rem 0;
}
.check-row input { accent-color: var(--accent); }

/* ---------- results / stats ---------- */

.stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
  gap: 1px;
  background: var(--rule-soft);
  border: 1px solid var(--rule-soft);
}
.stat {
  background: var(--paper);
  padding: 0.75rem 0.85rem;
}
.stat .k {
  font-family: var(--mono);
  font-size: 0.62rem;
  letter-spacing: 0.13em;
  text-transform: uppercase;
  color: var(--faint);
  display: block;
  margin-bottom: 0.25rem;
}
.stat .v {
  font-family: var(--mono);
  font-size: 1.02rem;
  color: var(--ink);
}
.stat .v.accent { color: var(--accent); }

.price-display {
  display: flex;
  flex-wrap: wrap;
  gap: 1px;
  background: var(--rule-soft);
  border: 1px solid var(--rule-soft);
  margin-bottom: 1.4rem;
}
.price-display .stat { flex: 1 1 160px; padding: 1rem 1.1rem; }
.price-display .stat .v { font-size: 1.55rem; }

/* data tables */
table.data {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--mono);
  font-size: 0.78rem;
  margin: 1.2rem 0;
}
table.data th {
  text-align: left;
  font-weight: 500;
  font-size: 0.65rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--faint);
  border-bottom: 1px solid var(--rule);
  padding: 0.5rem 0.9rem 0.5rem 0;
}
table.data td {
  border-bottom: 1px solid var(--rule-soft);
  padding: 0.48rem 0.9rem 0.48rem 0;
  color: var(--ink-soft);
}
table.data td.num, table.data th.num { text-align: right; }
table.data td:first-child { color: var(--ink); }

/* ---------- charts ---------- */

.chart {
  width: 100%;
  min-height: 340px;
  border: 1px solid var(--rule);
  background: var(--paper);
  margin: 1.4rem 0;
}
.chart.tall { min-height: 420px; }
.chart.short { min-height: 280px; }

.chart-caption, .figure-note {
  font-family: var(--mono);
  font-size: 0.68rem;
  letter-spacing: 0.05em;
  color: var(--faint);
  margin: -0.7rem 0 1.6rem;
}

.chart-pair {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.4rem;
}
@media (max-width: 880px) {
  .chart-pair { grid-template-columns: 1fr; }
}

/* ---------- callouts / math ---------- */

.note {
  border-left: 2px solid var(--accent);
  padding: 0.15rem 0 0.15rem 1.3rem;
  margin: 1.8rem 0;
  color: var(--ink-soft);
  font-size: 0.98rem;
}
.note .note-label {
  font-family: var(--mono);
  font-size: 0.64rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
  display: block;
  margin-bottom: 0.35rem;
}

.math-block {
  margin: 1.6rem 0;
  padding: 1.2rem 1.4rem;
  border: 1px solid var(--rule-soft);
  background: rgba(255,255,255,0.45);
  overflow-x: auto;
}

.katex { font-size: 1.04em; }
.katex-display { margin: 0.4em 0; }

/* definition-style list for assumptions */
dl.assume { margin: 1.4rem 0; }
dl.assume dt {
  font-weight: 600;
  margin-top: 0.9rem;
}
dl.assume dd {
  margin: 0.15rem 0 0 0;
  color: var(--ink-soft);
  font-size: 0.97rem;
}

ul.refs, ol.refs { padding-left: 1.3rem; }
ul.refs li, ol.refs li { margin-bottom: 0.45rem; font-size: 0.97rem; color: var(--ink-soft); }

/* research question block */
.rq {
  margin: 2.2rem 0;
  padding: 1.8rem 1.9rem;
  border: 1px solid var(--rule);
  background: var(--paper-deep);
}
.rq .kicker { margin-bottom: 0.7rem; }
.rq p {
  font-size: 1.18rem;
  font-style: italic;
  color: var(--ink-soft);
  margin: 0;
}

/* mono inline tag */
.tag {
  font-family: var(--mono);
  font-size: 0.66rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  border: 1px solid var(--rule);
  color: var(--muted);
  padding: 0.14rem 0.5rem;
  white-space: nowrap;
}
.tag.warn { border-color: var(--accent-dim); color: var(--accent); }

sup, sub { line-height: 0; }

/* about page */
.credo {
  font-size: 1.5rem;
  font-style: italic;
  line-height: 1.4;
  color: var(--ink-soft);
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
  padding: 2.2rem 0;
  margin: 2.6rem 0;
  max-width: 26em;
}

@media (max-width: 640px) {
  body { font-size: 16.5px; }
  h1 { font-size: 1.9rem; }
  .hero { padding: 3rem 0 2.4rem; }
  .thesis blockquote { font-size: 1.2rem; }
}

@media print {
  .site-nav, .panel, .seg, .btn { display: none; }
}