/* lpviz documentation — shared stylesheet. No JS, no external assets. */
:root {
  --bg: #fcfcfc;
  --fg: #1a1a1a;
  --muted: #595959;
  --border: #e2e2e2;
  --accent: #1d4ed8;
  --accent-soft: rgba(29, 78, 216, 0.08);
  --code-bg: #f2f2f2;
  --simplex: #d64550;
  --ipm: #2563eb;
  --pdhg: #0f9960;
  --central: #8250df;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #141414;
    --fg: #e6e6e6;
    --muted: #a3a3a3;
    --border: #2e2e2e;
    --accent: #7aa2ff;
    --accent-soft: rgba(122, 162, 255, 0.12);
    --code-bg: #222;
    --simplex: #ef7580;
    --ipm: #6d9bff;
    --pdhg: #3fbf8a;
    --central: #ab7ff0;
  }
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font:
    16px/1.65 system-ui,
    -apple-system,
    "Segoe UI",
    Roboto,
    sans-serif;
  -webkit-text-size-adjust: 100%;
}

code,
kbd,
.eq,
.mono {
  font-family: "SF Mono", SFMono-Regular, ui-monospace, Menlo, Consolas, monospace;
}

.site-header {
  border-bottom: 1px solid var(--border);
}

.site-header nav {
  max-width: 46rem;
  margin: 0 auto;
  padding: 0.7rem 1.25rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1.1rem;
  align-items: baseline;
}

.site-header .brand {
  font-family: "SF Mono", SFMono-Regular, ui-monospace, Menlo, Consolas, monospace;
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--fg);
  text-decoration: none;
}

.site-header a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.92rem;
}

.site-header a:hover,
.site-header a.is-active {
  color: var(--accent);
}

main {
  max-width: 46rem;
  margin: 0 auto;
  padding: 1.5rem 1.25rem 3rem;
}

h1 {
  font-size: 1.85rem;
  line-height: 1.25;
  margin: 0.8rem 0 0.4rem;
  letter-spacing: -0.015em;
}

h2 {
  font-size: 1.3rem;
  margin: 2.2rem 0 0.5rem;
  letter-spacing: -0.01em;
}

h3 {
  font-size: 1.05rem;
  margin: 1.6rem 0 0.4rem;
}

p {
  margin: 0.65rem 0;
}

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

.lede {
  font-size: 1.08rem;
  color: var(--muted);
  margin-bottom: 1.4rem;
}

.breadcrumbs {
  font-size: 0.85rem;
  color: var(--muted);
  margin-top: 0.5rem;
}

.breadcrumbs a {
  color: var(--muted);
}

ul,
ol {
  padding-left: 1.4rem;
  margin: 0.65rem 0;
}

li {
  margin: 0.3rem 0;
}

var {
  font-style: italic;
  font-family: Georgia, "Times New Roman", serif;
  font-size: 1.05em;
}

/* Display equations: plain HTML math, monospace-adjacent serif hybrid */
.eq {
  display: block;
  margin: 1rem 0;
  padding: 0.75rem 1rem;
  background: var(--accent-soft);
  border-radius: 6px;
  overflow-x: auto;
  white-space: nowrap;
  font-size: 0.98rem;
  text-align: center;
}

.eq var,
p var,
li var,
td var {
  font-family: Georgia, "Times New Roman", serif;
}

code {
  background: var(--code-bg);
  padding: 0.1em 0.35em;
  border-radius: 4px;
  font-size: 0.88em;
}

pre {
  background: var(--code-bg);
  padding: 0.8rem 1rem;
  border-radius: 6px;
  overflow-x: auto;
  font-size: 0.85rem;
  line-height: 1.5;
}

pre code {
  background: none;
  padding: 0;
}

kbd {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-bottom-width: 2px;
  border-radius: 4px;
  padding: 0.05em 0.4em;
  font-size: 0.85em;
}

table {
  border-collapse: collapse;
  width: 100%;
  margin: 1rem 0;
  font-size: 0.92rem;
}

.table-scroll {
  overflow-x: auto;
}

th,
td {
  border: 1px solid var(--border);
  padding: 0.45rem 0.65rem;
  text-align: left;
  vertical-align: top;
}

th {
  background: var(--code-bg);
  font-weight: 600;
}

figure {
  margin: 1.5rem 0;
  text-align: center;
}

figure svg {
  max-width: 100%;
  height: auto;
}

figcaption {
  font-size: 0.85rem;
  color: var(--muted);
  margin-top: 0.4rem;
}

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 1.2rem;
  justify-content: center;
  font-size: 0.85rem;
  color: var(--muted);
  margin-top: 0.5rem;
}

.legend .swatch {
  display: inline-block;
  width: 0.9em;
  height: 0.25em;
  border-radius: 2px;
  vertical-align: middle;
  margin-right: 0.35em;
}

.callout {
  border-left: 3px solid var(--accent);
  background: var(--accent-soft);
  padding: 0.6rem 1rem;
  margin: 1rem 0;
  border-radius: 0 6px 6px 0;
  font-size: 0.95rem;
}

.pager {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 2.5rem;
}

.pager a {
  flex: 1 1 14rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.7rem 0.9rem;
  text-decoration: none;
  color: var(--fg);
}

.pager a:hover {
  border-color: var(--accent);
}

.pager .dir {
  display: block;
  font-size: 0.78rem;
  color: var(--muted);
}

.pager .next {
  text-align: right;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr));
  gap: 0.75rem;
  margin: 1rem 0;
}

.card-grid a {
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.8rem 1rem;
  text-decoration: none;
  color: var(--fg);
  display: block;
}

.card-grid a:hover {
  border-color: var(--accent);
}

.card-grid strong {
  color: var(--accent);
}

.card-grid p {
  margin: 0.25rem 0 0;
  font-size: 0.88rem;
  color: var(--muted);
}

.site-footer {
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.85rem;
}

.site-footer div {
  max-width: 46rem;
  margin: 0 auto;
  padding: 1.2rem 1.25rem 2rem;
}

.site-footer a {
  color: var(--muted);
}

dt {
  font-weight: 600;
  margin-top: 1rem;
}

dd {
  margin: 0.25rem 0 0 0;
}