/* ---------- Reset & base ---------- */

:root {
  --color-bg: #fbfaf6;
  --color-paper: #ffffff;
  --color-ink: #1a1a1a;
  --color-ink-soft: #2a2a2a;
  --color-mute: #5a5a5a;
  --color-mute-2: #8a8580;
  --color-rule: #d8d3c8;
  --color-rule-soft: #e8e3d8;
  --color-code-bg: #f4f0e6;
  --color-code-border: #e6dfce;
  --color-accent: #8a2424;
  --color-accent-soft: #b54545;
  --color-callout-bg: #f6f3eb;
  --color-callout-border: #c6a674;

  --font-serif: "Source Serif 4", "Source Serif Pro", Charter, "Iowan Old Style", "Times New Roman", Georgia, serif;
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --measure: 38rem;          /* ~720px / 19px body */
  --measure-wide: 52rem;     /* ~960px for tables/code */

  --space-1: 0.5rem;
  --space-2: 1rem;
  --space-3: 1.5rem;
  --space-4: 2.25rem;
  --space-5: 3.5rem;
  --space-6: 5rem;
  --space-7: 7rem;
}

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

html {
  font-size: 18px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

body {
  margin: 0;
  font-family: var(--font-serif);
  font-feature-settings: "kern", "liga", "onum";
  font-variant-numeric: oldstyle-nums;
  line-height: 1.65;
  color: var(--color-ink);
  background: var(--color-bg);
}

::selection {
  background: rgba(138, 36, 36, 0.18);
}

/* ---------- Typography primitives ---------- */

p {
  margin: 0 0 1.15em;
}

a {
  color: var(--color-ink);
  text-decoration-color: var(--color-accent-soft);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color 120ms ease, text-decoration-color 120ms ease;
}

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

strong {
  font-weight: 600;
}

em {
  font-style: italic;
}

abbr {
  text-decoration: none;
  border-bottom: 1px dotted var(--color-mute);
}

hr {
  border: none;
  border-top: 1px solid var(--color-rule);
  margin: var(--space-5) 0;
}

blockquote {
  margin: 1.5em 0;
  padding: 0 0 0 1.25rem;
  border-left: 2px solid var(--color-rule);
  color: var(--color-ink-soft);
  font-style: italic;
}

small, .small {
  font-size: 0.85rem;
  color: var(--color-mute);
}

/* ---------- Headings ---------- */

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-serif);
  color: var(--color-ink);
  font-weight: 600;
  letter-spacing: -0.005em;
  line-height: 1.25;
  margin: 2em 0 0.6em;
}

h1 { font-size: 2.25rem; letter-spacing: -0.015em; }
h2 { font-size: 1.55rem; margin-top: 2.5em; }
h3 { font-size: 1.2rem; margin-top: 2em; }
h4 { font-size: 1.05rem; text-transform: none; letter-spacing: 0; }

h2 + h3, h3 + p { margin-top: 0.75em; }

/* ---------- Site navigation ---------- */

.site-nav {
  position: sticky;
  top: 0;
  z-index: 30;
  background: rgba(251, 250, 246, 0.94);
  backdrop-filter: saturate(140%) blur(8px);
  border-bottom: 1px solid var(--color-rule-soft);
}

.site-nav-inner {
  max-width: 72rem;
  margin: 0 auto;
  padding: 0.85rem 1.5rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem 1.5rem;
}

.site-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: 0.01em;
  text-decoration: none;
  color: var(--color-ink);
  padding: 0.15rem 0;
}

.site-brand img {
  display: block;
  height: 48px;
  width: auto;
  background: transparent;
}

@media (max-width: 38rem) {
  .site-brand img { height: 40px; }
  .site-brand { font-size: 1rem; }
}

.site-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1.1rem;
  font-family: var(--font-sans);
  font-size: 0.875rem;
}

.site-links a {
  color: var(--color-mute);
  text-decoration: none;
  padding: 0.25rem 0;
  border-bottom: 1px solid transparent;
}

.site-links a:hover {
  color: var(--color-ink);
  border-bottom-color: var(--color-accent-soft);
}

.site-links a[aria-current="page"] {
  color: var(--color-ink);
  border-bottom-color: var(--color-accent);
}

/* ---------- Page shell ---------- */

.page {
  padding: var(--space-6) 1.5rem var(--space-7);
}

.page-article {
  max-width: var(--measure);
  margin: 0 auto;
}

.page-header {
  margin-bottom: var(--space-5);
}

.page-eyebrow {
  font-family: var(--font-sans);
  text-transform: uppercase;
  letter-spacing: 0.16em;
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--color-accent);
  margin: 0 0 0.85rem;
}

.page-title {
  margin: 0;
  font-size: 2.6rem;
  line-height: 1.12;
  letter-spacing: -0.02em;
  font-weight: 600;
}

.page-lede {
  margin: 1.25rem 0 0;
  font-size: 1.2rem;
  line-height: 1.55;
  color: var(--color-ink-soft);
  font-style: italic;
  max-width: 34rem;
}

.page-body > * {
  max-width: var(--measure);
}

.page-body .wide,
.page-body pre,
.page-body table,
.page-body figure {
  max-width: var(--measure-wide);
  margin-left: auto;
  margin-right: auto;
}

/* ---------- Section dividers ---------- */

.section-rule {
  display: block;
  width: 3rem;
  border: none;
  border-top: 2px solid var(--color-accent);
  margin: var(--space-5) 0 var(--space-4);
}

/* ---------- Lists ---------- */

ul, ol {
  padding-left: 1.4em;
  margin: 0 0 1.2em;
}

ul li, ol li {
  margin: 0.35em 0;
}

ul.tight li, ol.tight li {
  margin: 0.15em 0;
}

ul.unstyled {
  list-style: none;
  padding-left: 0;
}

/* Definition lists for term/explanation pairs */
dl.terms {
  margin: 0 0 1.5em;
}

dl.terms dt {
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: 0.01em;
  color: var(--color-ink);
  margin-top: 1.15em;
}

dl.terms dt:first-child {
  margin-top: 0;
}

dl.terms dd {
  margin: 0.25em 0 0;
  color: var(--color-ink-soft);
}

/* ---------- Code ---------- */

code, kbd, samp, pre {
  font-family: var(--font-mono);
  font-feature-settings: normal;
  font-variant-numeric: normal;
}

:not(pre) > code {
  background: var(--color-code-bg);
  border: 1px solid var(--color-code-border);
  border-radius: 3px;
  padding: 0.05em 0.35em;
  font-size: 0.85em;
  color: var(--color-ink);
}

pre {
  background: var(--color-code-bg);
  border: 1px solid var(--color-code-border);
  border-left: 3px solid var(--color-accent-soft);
  border-radius: 3px;
  padding: 1rem 1.15rem;
  margin: 1.5rem auto;
  overflow-x: auto;
  font-size: 0.85rem;
  line-height: 1.55;
}

pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: inherit;
}

/* ---------- Tables ---------- */

table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem auto;
  font-family: var(--font-sans);
  font-size: 0.9rem;
}

th, td {
  text-align: left;
  padding: 0.6rem 0.85rem;
  border-bottom: 1px solid var(--color-rule-soft);
  vertical-align: top;
}

th {
  font-weight: 600;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-mute);
  border-bottom: 1.5px solid var(--color-rule);
}

tbody tr:hover {
  background: rgba(0, 0, 0, 0.012);
}

table code {
  font-size: 0.82em;
}

/* ---------- Callouts ---------- */

.callout {
  margin: 1.75rem auto;
  padding: 1rem 1.25rem;
  background: var(--color-callout-bg);
  border-left: 3px solid var(--color-callout-border);
  border-radius: 2px;
  font-size: 0.95rem;
}

.callout p:last-child { margin-bottom: 0; }

.callout-label {
  display: block;
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-callout-border);
  margin-bottom: 0.4rem;
}

.callout--note { border-left-color: var(--color-callout-border); }
.callout--warn { border-left-color: #b27a1c; background: #faf2e0; }
.callout--warn .callout-label { color: #8a5a13; }

/* ---------- Cards (used on home page) ---------- */

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr));
  gap: 1.25rem;
  margin: 2rem auto 2.5rem;
  max-width: var(--measure-wide);
}

.idea-card {
  background: var(--color-paper);
  border: 1px solid var(--color-rule-soft);
  border-radius: 3px;
  padding: 1.5rem 1.5rem 1.4rem;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  text-decoration: none;
  color: inherit;
  transition: border-color 140ms ease, transform 140ms ease;
}

.idea-card:hover {
  border-color: var(--color-accent-soft);
  text-decoration: none;
  color: inherit;
}

.idea-card .card-number {
  font-family: var(--font-sans);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  font-weight: 600;
  color: var(--color-accent);
  text-transform: uppercase;
}

.idea-card .card-title {
  font-family: var(--font-serif);
  font-size: 1.2rem;
  font-weight: 600;
  letter-spacing: -0.005em;
  margin: 0;
}

.idea-card .card-body {
  font-size: 0.95rem;
  color: var(--color-ink-soft);
  margin: 0;
}

.idea-card .card-more {
  font-family: var(--font-sans);
  font-size: 0.78rem;
  color: var(--color-accent);
  margin-top: 0.5rem;
  letter-spacing: 0.02em;
}

/* ---------- Index list (subtle TOC) ---------- */

.index-list {
  list-style: none;
  padding: 0;
  margin: 1.5rem 0 0;
  border-top: 1px solid var(--color-rule-soft);
}

.index-list li {
  border-bottom: 1px solid var(--color-rule-soft);
  margin: 0;
}

.index-list a {
  display: grid;
  grid-template-columns: 9rem 1fr;
  gap: 1.5rem;
  align-items: baseline;
  padding: 0.9rem 0;
  text-decoration: none;
  color: var(--color-ink);
}

.index-list a:hover {
  color: var(--color-accent);
}

.index-list .index-label {
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 0.84rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-mute);
}

.index-list a:hover .index-label {
  color: var(--color-accent);
}

.index-list .index-desc {
  font-size: 0.98rem;
  color: var(--color-ink-soft);
}

@media (max-width: 38rem) {
  .index-list a {
    grid-template-columns: 1fr;
    gap: 0.2rem;
  }
}

/* ---------- ASCII diagrams ---------- */

.ascii {
  background: var(--color-paper);
  border: 1px solid var(--color-rule-soft);
  border-radius: 3px;
  padding: 1.25rem 1.5rem;
  margin: 1.75rem auto;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.45;
  white-space: pre;
  overflow-x: auto;
  color: var(--color-ink-soft);
}

/* ---------- Mermaid diagrams ---------- */

.diagram {
  margin: 2rem auto;
  max-width: var(--measure-wide);
  background: var(--color-paper);
  border: 1px solid var(--color-rule-soft);
  border-radius: 3px;
  padding: 1.5rem 1rem 1.25rem;
  text-align: center;
}

.diagram-figcaption {
  display: block;
  margin: 0.75rem auto 0;
  font-family: var(--font-sans);
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-mute);
}

/* Hide raw Mermaid source while it's being processed */
.mermaid:not([data-processed="true"]) {
  visibility: hidden;
  min-height: 320px;
}

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

/* Node and edge tuning */
.mermaid .node rect,
.mermaid .node polygon,
.mermaid .node circle,
.mermaid .node path {
  stroke-width: 1px;
}

.mermaid .cluster rect {
  stroke-dasharray: 3 4;
  stroke-width: 1px;
  fill: transparent !important;
}

.mermaid .cluster .nodeLabel {
  font-family: var(--font-sans);
  font-size: 0.74rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-mute);
  font-weight: 600;
}

.mermaid .nodeLabel,
.mermaid .edgeLabel {
  font-family: var(--font-sans);
}

.mermaid .nodeLabel {
  font-size: 0.92rem;
  line-height: 1.35;
}

.mermaid .edgeLabel {
  font-size: 0.74rem;
  letter-spacing: 0.04em;
  color: var(--color-mute) !important;
  background: var(--color-bg) !important;
  padding: 1px 6px;
}

.mermaid .edgeLabel p {
  margin: 0;
  background: var(--color-bg) !important;
  color: var(--color-mute) !important;
}

.mermaid .edgePath .path {
  stroke-width: 1.2px;
}

.mermaid .marker {
  fill: var(--color-accent);
  stroke: var(--color-accent);
}

/* ---------- Stylized ampersand ---------- */

.amp {
  font-family: "Source Serif 4", "EB Garamond", "Adobe Caslon Pro", Baskerville, Garamond, serif;
  font-style: italic;
  font-weight: 400;
  color: var(--color-accent);
  font-size: 1.12em;
  font-feature-settings: "kern", "liga", "dlig", "salt";
  font-variation-settings: "opsz" 60;
  letter-spacing: 0.01em;
  padding: 0 0.04em;
  line-height: 1;
}

h1 .amp, h2 .amp, h3 .amp {
  font-size: 1.18em;
}

.page-title .amp {
  font-size: 1.22em;
  padding: 0 0.06em;
}

/* ---------- Drop cap (used sparingly on the lede paragraph of major essays) ---------- */

.dropcap::first-letter {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: 3.4em;
  line-height: 0.85;
  float: left;
  padding: 0.1em 0.1em 0 0;
  color: var(--color-accent);
}

/* ---------- Pull quote ---------- */

.pull {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 1.3rem;
  line-height: 1.4;
  color: var(--color-ink-soft);
  border-top: 1px solid var(--color-rule);
  border-bottom: 1px solid var(--color-rule);
  padding: 1.25rem 0;
  margin: 2rem 0;
  max-width: 32rem;
}

/* ---------- Footnotes ---------- */

.footnotes {
  margin-top: var(--space-5);
  padding-top: var(--space-3);
  border-top: 1px solid var(--color-rule);
  font-size: 0.9rem;
  color: var(--color-ink-soft);
}

.footnotes ol {
  padding-left: 1.5em;
}

/* ---------- Footer ---------- */

.site-footer {
  margin-top: var(--space-6);
  padding: var(--space-5) 1.5rem var(--space-4);
  border-top: 1px solid var(--color-rule);
  background: transparent;
}

.site-footer-inner {
  max-width: var(--measure-wide);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 2rem;
}

.footer-col p { margin: 0 0 0.3rem; }

.footer-heading {
  font-family: var(--font-sans);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-mute);
  margin-bottom: 0.65rem !important;
}

.footer-muted {
  color: var(--color-ink-soft);
  font-size: 0.95rem;
  font-style: italic;
  max-width: 22rem;
}

.footer-list {
  list-style: none;
  padding: 0;
  margin: 0;
  font-family: var(--font-sans);
  font-size: 0.88rem;
}

.footer-list li { margin: 0.2rem 0; }

.footer-list a {
  color: var(--color-ink-soft);
  text-decoration: none;
}

.footer-list a:hover { color: var(--color-accent); }

.site-footer-meta {
  max-width: var(--measure-wide);
  margin: var(--space-4) auto 0;
  padding-top: var(--space-2);
  border-top: 1px solid var(--color-rule-soft);
  font-family: var(--font-sans);
  font-size: 0.78rem;
  color: var(--color-mute);
}

.site-footer-meta p { margin: 0; }

@media (max-width: 38rem) {
  .site-footer-inner { grid-template-columns: 1fr; gap: 1.5rem; }
}

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

@media (max-width: 38rem) {
  html { font-size: 17px; }
  .page { padding: var(--space-4) 1.25rem var(--space-6); }
  .page-title { font-size: 2rem; }
  .site-nav-inner { padding: 0.7rem 1rem; }
  .site-links { width: 100%; }
}

/* ---------- Print ---------- */

@media print {
  .site-nav, .site-footer { display: none; }
  body { background: white; }
  pre { border-color: #ccc; }
}