:root {
  --sage: #87967d;
  --sage-dark: #6d7c63;
  --sage-soft: #eef0ea;
  --cream: #f4f1ea;
  --paper: #fdfcfa;
  --ink: #1c1c1a;
  --muted: #6b6a65;
  --line: #e2ded3;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  --sans: Montserrat, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.65;
  color: var(--ink);
  background: var(--cream);
}

/* ---------- top bar ---------- */
.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  background: var(--paper);
  border-bottom: 1px solid var(--line);
}
.topbar-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 10px 24px;
  display: flex;
  align-items: center;
  gap: 12px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
  color: var(--ink);
  font-weight: 600;
}
.brand-name em { color: var(--sage-dark); font-style: normal; }
.brand-sub { color: var(--muted); font-size: 13px; }
.topbar-link {
  margin-left: auto;
  color: var(--sage-dark);
  font-size: 13px;
  text-decoration: none;
  border: 1px solid var(--sage);
  border-radius: 6px;
  padding: 3px 10px;
}
.topbar-link:hover { background: var(--sage-soft); }

/* ---------- layout ---------- */
.layout {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 250px minmax(0, 1fr);
  gap: 32px;
  padding: 24px;
  align-items: start;
}

/* ---------- sidebar ---------- */
.sidebar {
  position: sticky;
  top: 66px;
  max-height: calc(100vh - 90px);
  overflow-y: auto;
}
.nav-search {
  width: 100%;
  padding: 7px 10px;
  margin-bottom: 12px;
  font: inherit;
  font-size: 13px;
  color: var(--ink);
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 6px;
  outline: none;
}
.nav-search:focus { border-color: var(--sage); }
.nav-label {
  margin: 14px 0 4px;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}
.nav-group a {
  display: block;
  padding: 4px 10px;
  margin: 1px 0;
  font-size: 13.5px;
  color: var(--ink);
  text-decoration: none;
  border-left: 2px solid transparent;
  border-radius: 0 6px 6px 0;
}
.nav-group a:hover { background: var(--sage-soft); }
.nav-group a.active {
  border-left-color: var(--sage);
  background: var(--sage-soft);
  color: var(--sage-dark);
  font-weight: 600;
}
.nav-empty {
  display: none;
  padding: 8px 10px;
  font-size: 13px;
  color: var(--muted);
}

/* ---------- content ---------- */
.content { min-width: 0; }
.doc {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 28px 32px;
  margin-bottom: 24px;
  scroll-margin-top: 76px;
}
h1 { font-size: 26px; font-weight: 600; margin: 0 0 14px; letter-spacing: -0.01em; }
h2 { font-size: 18px; font-weight: 600; margin: 26px 0 10px; color: var(--sage-dark); }
h1 code, h2 code { font-family: var(--mono); font-size: 0.85em; background: var(--sage-soft); padding: 2px 6px; border-radius: 5px; }
p { margin: 10px 0; }
ul, ol { margin: 10px 0; padding-left: 22px; }
li { margin: 5px 0; }
a { color: var(--sage-dark); }
strong { font-weight: 600; }
code {
  font-family: var(--mono);
  font-size: 0.86em;
  background: var(--sage-soft);
  padding: 1.5px 5px;
  border-radius: 4px;
}
.pill {
  display: inline-block;
  vertical-align: middle;
  margin-left: 8px;
  font-size: 12px;
  font-weight: 600;
  color: var(--sage-dark);
  background: var(--sage-soft);
  border: 1px solid var(--sage);
  border-radius: 999px;
  padding: 1px 9px;
}
.note {
  background: var(--sage-soft);
  border-left: 3px solid var(--sage);
  border-radius: 0 6px 6px 0;
  padding: 10px 14px;
}

/* ---------- tables ---------- */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 14px 0;
  font-size: 13.5px;
}
th, td {
  text-align: left;
  vertical-align: top;
  padding: 8px 10px;
  border-bottom: 1px solid var(--line);
}
thead th {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--muted);
  border-bottom: 2px solid var(--line);
}
tbody tr:hover { background: #faf9f5; }
td code, th code { white-space: nowrap; }

/* ---------- code blocks ---------- */
pre {
  background: #23251f;
  color: #e8e6df;
  border-radius: 8px;
  padding: 14px 16px;
  overflow-x: auto;
  font-size: 13px;
  line-height: 1.55;
  position: relative;
}
pre code { background: none; padding: 0; color: inherit; font-size: inherit; }
.copy-btn {
  position: absolute;
  top: 8px;
  right: 8px;
  font: 11px var(--sans);
  color: #cfcabf;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.18);
  border-radius: 5px;
  padding: 2px 8px;
  cursor: pointer;
  opacity: 0;
  transition: opacity 0.15s;
}
pre:hover .copy-btn { opacity: 1; }
.copy-btn:hover { background: rgba(255,255,255,0.16); }

/* ---------- diagram ---------- */
.diagram {
  display: flex;
  align-items: stretch;
  gap: 8px;
  flex-wrap: wrap;
  margin: 18px 0;
}
.node {
  flex: 1 1 160px;
  background: var(--paper);
  border: 1.5px solid var(--sage);
  border-radius: 8px;
  padding: 12px 14px;
  font-weight: 600;
  font-size: 13.5px;
  text-align: center;
  align-self: center;
}
.node small { display: block; font-weight: 400; color: var(--muted); margin-top: 4px; }
.node.accent { background: var(--sage); color: #fff; }
.node.accent small { color: #e3e8de; }
.edge {
  align-self: center;
  font-size: 12px;
  color: var(--muted);
  text-align: center;
  padding: 0 2px;
  white-space: nowrap;
}
.edge small { display: block; font-size: 11px; }

/* ---------- flow list ---------- */
ol.flow { counter-reset: step; list-style: none; padding-left: 0; }
ol.flow li {
  counter-increment: step;
  position: relative;
  padding: 8px 12px 8px 44px;
  margin: 6px 0;
  background: var(--sage-soft);
  border-radius: 8px;
}
ol.flow li::before {
  content: counter(step);
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--sage);
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* ---------- footer ---------- */
footer {
  padding: 8px 8px 40px;
  color: var(--muted);
  font-size: 13px;
}

/* ---------- mobile ---------- */
@media (max-width: 860px) {
  .layout { grid-template-columns: 1fr; gap: 16px; padding: 16px; }
  .sidebar { position: static; max-height: none; }
  #nav { display: flex; flex-wrap: wrap; gap: 4px; }
  .nav-group { display: contents; }
  .nav-label { display: none; }
  .nav-group a { border: 1px solid var(--line); border-radius: 999px; padding: 4px 12px; }
  .nav-group a.active { border-color: var(--sage); }
  .doc { padding: 20px 18px; }
  .brand-sub { display: none; }
}