/* DD-Engine shared styles */
:root {
  --bg: #fcfcfc;
  --fg: #1a1a1a;
  --muted: #5a5a5a;
  --faint: #888;
  --accent: #1c3a5e;
  --link: #8b1a1a;
  --border: #d0d0d0;
  --code-bg: #f3f3f0;
  --table-border: #c8c8c8;
  --row-alt: #f7f7f4;
  --pass: #1a6e1a;
  --fail: #8b1a1a;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: 'Charter','Cambria','Georgia',serif;
  line-height: 1.65;
  color: var(--fg);
  background: var(--bg);
  max-width: 820px;
  margin: 0 auto;
  padding: 1.5rem 1.5rem 4rem;
  font-size: 16px;
}

/* Site nav */
.site-nav {
  display: flex;
  gap: 0.3rem;
  flex-wrap: wrap;
  padding-bottom: 0.8rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 2rem;
  font-family: 'Helvetica Neue','Arial',sans-serif;
  font-size: 0.85rem;
}
.site-nav a {
  padding: 0.35rem 0.7rem;
  color: var(--muted);
  border: 1px solid var(--border);
  border-radius: 3px;
  text-decoration: none;
}
.site-nav a:hover { border-color: var(--accent); color: var(--accent); }
.site-nav a.active {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
}
.site-brand {
  font-weight: 700;
  margin-right: 0.5rem;
  padding: 0.35rem 0.7rem;
  color: var(--accent);
  font-family: 'Charter',serif;
  letter-spacing: -0.01em;
}

h1, h2, h3, h4 {
  font-family: 'Charter','Cambria','Georgia',serif;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: -0.005em;
}
h1 { font-size: 2rem; margin-bottom: 0.3rem; line-height: 1.2; }
h2 {
  font-size: 1.3rem;
  margin: 2.5rem 0 0.8rem;
  padding-bottom: 0.2rem;
  border-bottom: 1px solid var(--border);
  font-variant: small-caps;
  letter-spacing: 0.04em;
}
h3 { font-size: 1.1rem; margin: 1.6rem 0 0.5rem; font-weight: 600; }
h4 {
  font-size: 0.95rem;
  margin: 1.2rem 0 0.4rem;
  color: var(--muted);
  font-weight: 600;
  font-variant: small-caps;
  letter-spacing: 0.03em;
}
p { margin-bottom: 0.9rem; }
.lead {
  font-size: 1.1rem;
  color: var(--muted);
  font-style: italic;
  margin: 0.8rem 0 1.5rem;
}
a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; }

code {
  font-family: 'JetBrains Mono','SF Mono','Consolas','Monaco',monospace;
  font-size: 0.86em;
  background: var(--code-bg);
  padding: 0.08em 0.28em;
  border-radius: 2px;
  color: #2a2a2a;
}
pre {
  background: var(--code-bg);
  padding: 0.9rem 1.1rem;
  overflow-x: auto;
  font-size: 0.82rem;
  line-height: 1.45;
  margin: 1rem 0;
  border-left: 2px solid var(--border);
}
pre code { background: none; padding: 0; font-size: inherit; color: inherit; }

table {
  width: 100%;
  border-collapse: collapse;
  margin: 1rem 0;
  font-size: 0.91rem;
}
th, td {
  text-align: left;
  padding: 0.5rem 0.7rem;
  border: 1px solid var(--table-border);
  vertical-align: top;
}
th {
  background: var(--accent);
  color: white;
  font-weight: 600;
  font-size: 0.82rem;
  letter-spacing: 0.03em;
  font-variant: small-caps;
}
tr:nth-child(even) td { background: var(--row-alt); }

.verdict-pass { color: var(--pass); font-weight: 600; }
.verdict-fail { color: var(--fail); font-style: italic; }
.num { font-family: 'JetBrains Mono',monospace; font-size: 0.92em; }
.check { color: var(--pass); font-weight: 700; }
.cross { color: var(--fail); font-weight: 700; }

ul, ol { margin: 0.8rem 0 0.8rem 1.5rem; }
li { margin-bottom: 0.3rem; }

/* Cards / boxes */
.box {
  background: white;
  border: 1px solid var(--border);
  padding: 1rem 1.3rem;
  margin: 1.2rem 0;
  border-radius: 3px;
}
.axiom {
  background: white;
  padding: 1.2rem 1.5rem;
  margin: 1.5rem 0;
  border-left: 3px solid var(--accent);
}
.axiom-label {
  font-family: 'Helvetica Neue',sans-serif;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--muted);
  margin-bottom: 0.5rem;
}

.equation {
  background: white;
  padding: 0.7rem 1.1rem;
  margin: 0.9rem 0;
  text-align: center;
  font-family: 'Cambria Math','STIX','Charter',serif;
  font-size: 1.05rem;
  border: 1px solid var(--border);
}

/* Stats grid */
.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit,minmax(140px,1fr));
  gap: 0.6rem;
  margin: 1.2rem 0;
}
.stat {
  background: white;
  border: 1px solid var(--border);
  padding: 0.8rem 1rem;
  text-align: center;
}
.stat-num {
  font-family: 'JetBrains Mono',monospace;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent);
  display: block;
  line-height: 1.1;
}
.stat-label {
  font-size: 0.78rem;
  color: var(--muted);
  margin-top: 0.3rem;
  font-variant: small-caps;
  letter-spacing: 0.04em;
}

/* SVG diagrams */
.diagram {
  margin: 1.5rem 0;
  text-align: center;
}
.diagram svg {
  max-width: 100%;
  height: auto;
  background: white;
  border: 1px solid var(--border);
}
.diagram-caption {
  font-size: 0.82rem;
  color: var(--muted);
  margin-top: 0.4rem;
  font-style: italic;
}

/* Cascade visualization */
.cascade-list {
  font-family: 'JetBrains Mono','Consolas',monospace;
  font-size: 0.86rem;
  line-height: 1.85;
  background: var(--code-bg);
  padding: 1.2rem 1.5rem;
  margin: 1rem 0;
  overflow-x: auto;
  border-left: 2px solid var(--accent);
}
.cascade-list .arrow { color: var(--accent); margin: 0 0.3em; }
.cascade-list .ref { color: var(--muted); font-size: 0.9em; font-style: italic; }

footer {
  margin-top: 4rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
  font-size: 0.82rem;
  color: var(--faint);
  text-align: center;
}

@media (max-width: 600px) {
  body { padding: 1.2rem 0.9rem 3rem; font-size: 15px; }
  h1 { font-size: 1.5rem; }
  h2 { font-size: 1.15rem; }
  .site-nav { font-size: 0.78rem; }
  .stat-num { font-size: 1.2rem; }
}