/* =========================================================================
   MNEMON — Ars Memoriae for self-hosted agent memory
   A treatise-grade type system on parchment, ruled by vermilion.
   ========================================================================= */

@import url('https://fonts.googleapis.com/css2?family=EB+Garamond:ital,wght@0,400;0,500;0,600;0,700;1,400;1,500&family=Inter:wght@300;400;500;600&family=JetBrains+Mono:wght@300;400;500;600&display=swap');

/* ---------- Tokens ---------- */
:root {
  /* Color */
  --paper:        oklch(0.965 0.012 85);
  --paper-deep:   oklch(0.945 0.014 82);
  --paper-edge:   oklch(0.92  0.018 80);
  --ink:          oklch(0.20  0.012 50);
  --ink-soft:     oklch(0.34  0.012 50);
  --ink-faint:    oklch(0.52  0.010 60);
  --ink-ghost:    oklch(0.72  0.008 70);
  --rule:         oklch(0.20 0.012 50 / 0.18);
  --rule-strong:  oklch(0.20 0.012 50 / 0.42);
  --rubric:       oklch(0.55 0.17 30);    /* vermilion */
  --rubric-deep:  oklch(0.42 0.16 30);
  --rubric-wash:  oklch(0.55 0.17 30 / 0.10);
  --gilt:         oklch(0.66 0.10 75);    /* faded gold, rare use */

  /* Type */
  --serif:    'EB Garamond', 'Georgia', serif;
  --sans:     'Inter', system-ui, -apple-system, sans-serif;
  --mono:     'JetBrains Mono', 'Menlo', monospace;

  /* Rhythm */
  --measure: 64rem;
  --gutter: 2rem;
  --hairline: 1px;

  /* Print-feel scales */
  --t-micro:  0.6875rem;   /* 11px */
  --t-small:  0.8125rem;   /* 13px */
  --t-body:   1rem;        /* 16px */
  --t-lead:   1.1875rem;   /* 19px */
  --t-h4:     1.375rem;
  --t-h3:     1.875rem;
  --t-h2:     2.75rem;
  --t-h1:     4.5rem;
  --t-display: 7rem;
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
img, svg { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: none; padding: 0; cursor: pointer; }
a { color: inherit; text-decoration: none; }

html {
  font-size: 16px;
  scroll-behavior: smooth;
  /* subtle paper grain */
  background:
    radial-gradient(ellipse at 20% 10%, oklch(0.93 0.018 80) 0%, transparent 55%),
    radial-gradient(ellipse at 85% 90%, oklch(0.93 0.018 80) 0%, transparent 50%),
    var(--paper);
  background-attachment: fixed;
  color: var(--ink);
}

body {
  font-family: var(--sans);
  font-size: var(--t-body);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  text-rendering: geometricPrecision;
}

/* ---------- Typography ---------- */
.serif    { font-family: var(--serif); }
.mono     { font-family: var(--mono); }
.italic   { font-style: italic; }
.smallcaps {
  font-variant: all-small-caps;
  letter-spacing: 0.12em;
}
.allcaps {
  text-transform: uppercase;
  letter-spacing: 0.18em;
  font-size: var(--t-micro);
}
.rubric { color: var(--rubric); }
.gilt   { color: var(--gilt); }
.dim    { color: var(--ink-faint); }
.ghost  { color: var(--ink-ghost); }

h1, h2, h3, h4 {
  font-family: var(--serif);
  font-weight: 500;
  line-height: 1.05;
  letter-spacing: -0.01em;
  color: var(--ink);
  margin: 0;
}
h1 { font-size: var(--t-h1); }
h2 { font-size: var(--t-h2); letter-spacing: -0.015em; }
h3 { font-size: var(--t-h3); }
h4 { font-size: var(--t-h4); font-weight: 600; }

p { margin: 0 0 1em; }

/* Drop cap, used sparingly */
.dropcap::first-letter {
  font-family: var(--serif);
  font-weight: 600;
  float: left;
  font-size: 5.4em;
  line-height: 0.86;
  padding: 0.06em 0.08em 0 0;
  margin-right: 0.04em;
  color: var(--rubric);
}

/* ---------- Layout primitives ---------- */
.frame {
  max-width: 1440px;
  margin: 0 auto;
  padding: 0 clamp(1.25rem, 4vw, 3.5rem);
}

.rule       { border: 0; border-top: var(--hairline) solid var(--rule); margin: 0; }
.rule-strong{ border: 0; border-top: var(--hairline) solid var(--rule-strong); margin: 0; }
.rule-double{
  border: 0;
  height: 6px;
  border-top: var(--hairline) solid var(--rule-strong);
  border-bottom: var(--hairline) solid var(--rule-strong);
  margin: 0;
}

.fig-no {
  font-family: var(--mono);
  font-size: var(--t-micro);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-faint);
}

/* ---------- Top bar (colophon-style) ---------- */
.colophon {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in oklch, var(--paper) 88%, transparent);
  backdrop-filter: blur(8px) saturate(1.05);
  -webkit-backdrop-filter: blur(8px) saturate(1.05);
  border-bottom: var(--hairline) solid var(--rule);
}
.colophon-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.85rem 0;
  gap: 2rem;
}
.brand {
  display: flex;
  align-items: baseline;
  gap: 0.65rem;
  font-family: var(--serif);
  font-weight: 600;
  font-size: 1.35rem;
  letter-spacing: 0.005em;
  white-space: nowrap;
  flex-shrink: 0;
}
.brand .dim { white-space: nowrap; }
.brand-mark {
  width: 22px; height: 22px;
  display: inline-block;
  position: relative;
  align-self: center;
}
.brand-mark::before, .brand-mark::after {
  content: ""; position: absolute; inset: 0;
  border: 1.25px solid var(--ink);
}
.brand-mark::before { transform: rotate(45deg); }
.brand-mark::after  { border-color: var(--rubric); transform: rotate(45deg) scale(0.55); background: var(--rubric); }

.nav {
  display: flex;
  gap: 2rem;
  font-size: var(--t-small);
  font-family: var(--sans);
  color: var(--ink-soft);
}
.nav a { position: relative; padding: 0.35rem 0; transition: color 0.2s; }
.nav a:hover { color: var(--ink); }
.nav a.is-active { color: var(--ink); }
.nav a.is-active::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: -0.4rem;
  height: 1px; background: var(--rubric);
}
.nav-meta {
  display: flex; align-items: center; gap: 1.25rem;
  font-family: var(--mono);
  font-size: var(--t-micro);
  color: var(--ink-faint);
  white-space: nowrap;
  flex-shrink: 0;
}
.nav-meta span, .nav-meta a { white-space: nowrap; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-family: var(--sans);
  font-weight: 500;
  font-size: 0.875rem;
  padding: 0.7rem 1.15rem;
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--paper);
  letter-spacing: 0.01em;
  transition: transform 0.15s ease, background 0.2s, color 0.2s;
}
.btn:hover { background: var(--rubric); border-color: var(--rubric); color: var(--paper); }
.btn:active { transform: translateY(1px); }
.btn-ghost {
  background: transparent; color: var(--ink); border-color: var(--ink);
}
.btn-ghost:hover { background: var(--ink); color: var(--paper); border-color: var(--ink); }
.btn-bare {
  border: 0; background: transparent; color: var(--ink-soft); padding: 0.4rem 0;
  border-bottom: 1px solid var(--rule); border-radius: 0;
}
.btn-bare:hover { color: var(--rubric); border-color: var(--rubric); background: transparent; }

.btn .arrow { display: inline-block; transition: transform 0.2s; }
.btn:hover .arrow { transform: translateX(3px); }

/* ---------- Marginalia + footnote glyphs ---------- */
.marginalia {
  font-family: var(--mono);
  font-size: var(--t-micro);
  line-height: 1.55;
  color: var(--ink-faint);
  letter-spacing: 0.02em;
}
.marginalia .num {
  display: inline-block;
  width: 1.4em;
  color: var(--rubric);
}

/* ---------- Pill / tag ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-family: var(--mono);
  font-size: var(--t-micro);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-faint);
  padding: 0.25rem 0.55rem;
  border: var(--hairline) solid var(--rule-strong);
  background: transparent;
}
.tag .dot { width: 5px; height: 5px; background: var(--rubric); border-radius: 0; display: inline-block; }

/* ---------- Section header (numbered, classical) ---------- */
.sec-head {
  display: grid;
  grid-template-columns: 8rem 1fr;
  gap: 2rem;
  align-items: baseline;
  padding-bottom: 1.25rem;
  margin-bottom: 2.5rem;
  border-bottom: var(--hairline) solid var(--rule-strong);
}
.sec-head .num {
  font-family: var(--mono);
  font-size: var(--t-micro);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--rubric);
}
.sec-head .title {
  font-family: var(--serif);
  font-size: clamp(1.75rem, 3.2vw, 2.5rem);
  font-weight: 500;
  line-height: 1.1;
  letter-spacing: -0.01em;
}
.sec-head .lede {
  display: block;
  margin-top: 0.5rem;
  font-family: var(--serif);
  font-style: italic;
  font-size: var(--t-lead);
  color: var(--ink-faint);
  font-weight: 400;
  letter-spacing: 0;
}

/* ---------- Pinned label, used on diagrams ---------- */
.pin-label {
  display: inline-flex;
  align-items: baseline;
  gap: 0.5rem;
  font-family: var(--mono);
  font-size: var(--t-micro);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink);
}
.pin-label::before {
  content: "";
  width: 7px; height: 7px;
  border: 1px solid var(--rubric);
  background: var(--rubric);
  display: inline-block;
  transform: translateY(-1px) rotate(45deg);
}

/* ---------- Code-ish inline ---------- */
code, kbd {
  font-family: var(--mono);
  font-size: 0.92em;
  background: var(--paper-deep);
  border: var(--hairline) solid var(--rule);
  padding: 0.05em 0.35em;
  color: var(--ink);
}

/* ---------- Footer ---------- */
.footer {
  margin-top: 6rem;
  padding: 3rem 0 2.5rem;
  border-top: var(--hairline) solid var(--rule-strong);
  font-family: var(--sans);
  font-size: var(--t-small);
  color: var(--ink-faint);
}
.footer a:hover { color: var(--rubric); }

/* ---------- Utility ---------- */
.center { text-align: center; }
.flex { display: flex; }
.between { justify-content: space-between; }
.gap-sm { gap: 0.75rem; }
.gap-md { gap: 1.5rem; }
.gap-lg { gap: 3rem; }
.mt-1 { margin-top: 1rem; }
.mt-2 { margin-top: 2rem; }
.mt-3 { margin-top: 3rem; }
.mt-4 { margin-top: 4rem; }
.mt-5 { margin-top: 5rem; }
.mt-8 { margin-top: 8rem; }
.mb-1 { margin-bottom: 1rem; }
.mb-2 { margin-bottom: 2rem; }
.mb-3 { margin-bottom: 3rem; }
.mb-4 { margin-bottom: 4rem; }
.mb-8 { margin-bottom: 8rem; }
.fill { width: 100%; }

/* selection */
::selection {
  background: var(--rubric);
  color: var(--paper);
}

/* scrollbar (subtle, paper-feel) */
* {
  scrollbar-width: thin;
  scrollbar-color: var(--ink-ghost) transparent;
}
*::-webkit-scrollbar { width: 8px; height: 8px; }
*::-webkit-scrollbar-thumb { background: var(--ink-ghost); border-radius: 0; }
*::-webkit-scrollbar-track { background: transparent; }