/* ============================================================
   Leviathan Documentation — design system
   Extends the leviathan-lang.com palette (see ../styles.css).
   ============================================================ */

:root {
  --bg-edge: #070d14;
  --bg-center: #0e1925;
  --panel-bg: #0b1420;
  --panel-bg-2: #0c1622;
  --panel-border: rgba(157, 184, 207, 0.12);
  --panel-border-strong: rgba(157, 184, 207, 0.22);

  --text-primary: #eaf0f5;
  --text-secondary: #9fb0bf;
  --text-muted: #6b7c8c;

  --accent: #9db8cf;
  --accent-strong: #d9e6ef;
  --accent-dim: #48607a;
  --accent-glow: rgba(127, 177, 224, 0.5);

  --code-bg: #080f18;
  --code-border: rgba(157, 184, 207, 0.15);
  --tok-keyword: #7fb1e0;
  --tok-type: #9dd6c0;
  --tok-string: #e0c17f;
  --tok-comment: #5b6b7a;
  --tok-num: #cf9fe0;
  --tok-fn: #cdd9e2;
  --tok-punct: #9fb0bf;

  --ok: #7fd6a8;
  --warn: #e0c17f;
  --danger: #e58f8f;
  --plan: #b79fe0;

  --font-display: "Space Grotesk", "Inter", system-ui, sans-serif;
  --font-body: "Inter", system-ui, -apple-system, sans-serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", Consolas, monospace;

  --sidebar-w: 264px;
  --toc-w: 210px;
  --topbar-h: 56px;
  --content-max: 820px;

  color-scheme: dark;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg-edge);
  color: var(--text-primary);
  font-family: var(--font-body);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-wrap: break-word;
}

a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-strong); }

img { max-width: 100%; display: block; }

/* offset anchored headings below the sticky topbar */
:target { scroll-margin-top: calc(var(--topbar-h) + 16px); }

/* ---------- Top bar ---------- */

.topbar {
  position: sticky;
  top: 0;
  z-index: 40;
  height: var(--topbar-h);
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 0 20px;
  background: rgba(7, 13, 20, 0.82);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--panel-border);
}

.topbar__brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text-primary);
  font-family: var(--font-display);
  font-weight: 600;
  letter-spacing: 0.12em;
  font-size: 0.82rem;
}
.topbar__brand img { border-radius: 4px; }
.topbar__brand:hover { color: var(--text-primary); }

.topbar__nav {
  display: flex;
  gap: 4px;
  margin-left: 8px;
}
.topbar__link {
  font-family: var(--font-display);
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-secondary);
  padding: 6px 12px;
  border-radius: 7px;
}
.topbar__link:hover { color: var(--text-primary); background: rgba(157, 184, 207, 0.06); }
.topbar__link--active { color: var(--accent-strong); background: rgba(127, 177, 224, 0.1); }

.topbar__spacer { flex: 1; }

.topbar__badge {
  font-family: var(--font-display);
  font-size: 0.62rem;
  font-weight: 600;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--text-secondary);
  padding: 5px 11px;
  border-radius: 999px;
  border: 1px solid var(--panel-border);
}

.menu-toggle {
  display: none;
  background: none;
  border: 1px solid var(--panel-border);
  border-radius: 7px;
  color: var(--text-secondary);
  width: 34px;
  height: 34px;
  cursor: pointer;
  align-items: center;
  justify-content: center;
}
.menu-toggle svg { width: 18px; height: 18px; }

/* ---------- Layout shell ---------- */

.shell {
  display: grid;
  grid-template-columns: var(--sidebar-w) minmax(0, 1fr);
  max-width: 1400px;
  margin: 0 auto;
}

/* ---------- Sidebar ---------- */

.sidebar {
  position: sticky;
  top: var(--topbar-h);
  align-self: start;
  height: calc(100vh - var(--topbar-h));
  overflow-y: auto;
  padding: 26px 14px 60px 22px;
  border-right: 1px solid var(--panel-border);
  scrollbar-width: thin;
  scrollbar-color: var(--accent-dim) transparent;
}
.sidebar::-webkit-scrollbar { width: 8px; }
.sidebar::-webkit-scrollbar-thumb { background: var(--accent-dim); border-radius: 4px; }

.side-group { margin-bottom: 22px; }
.side-group__title {
  font-family: var(--font-display);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.11em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin: 0 0 8px 10px;
}
.side-link {
  display: block;
  font-size: 0.88rem;
  color: var(--text-secondary);
  padding: 6px 10px;
  border-radius: 7px;
  border-left: 2px solid transparent;
}
.side-link:hover { color: var(--text-primary); background: rgba(157, 184, 207, 0.05); }
.side-link--active {
  color: var(--accent-strong);
  background: rgba(127, 177, 224, 0.09);
  border-left-color: var(--accent);
  font-weight: 500;
}

/* ---------- Main content ---------- */

.main {
  min-width: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr) var(--toc-w);
  gap: 40px;
  padding: 44px 40px 120px;
}
.main--no-toc { grid-template-columns: minmax(0, 1fr); }

.content {
  min-width: 0;
  max-width: var(--content-max);
}

/* ---------- On-this-page TOC ---------- */

.toc {
  position: sticky;
  top: calc(var(--topbar-h) + 44px);
  align-self: start;
  max-height: calc(100vh - var(--topbar-h) - 80px);
  overflow-y: auto;
  font-size: 0.82rem;
  border-left: 1px solid var(--panel-border);
  padding-left: 18px;
}
.toc__title {
  font-family: var(--font-display);
  font-size: 0.66rem;
  font-weight: 700;
  letter-spacing: 0.11em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin: 0 0 10px;
}
.toc a {
  display: block;
  color: var(--text-muted);
  padding: 4px 0;
  border-left: 2px solid transparent;
  padding-left: 12px;
  margin-left: -14px;
}
.toc a:hover { color: var(--text-secondary); }
.toc a.toc--sub { padding-left: 26px; font-size: 0.78rem; }
.toc a.toc--active { color: var(--accent-strong); border-left-color: var(--accent); }

/* ---------- Doc typography ---------- */

.content h1 {
  font-family: var(--font-display);
  font-size: clamp(1.9rem, 3.4vw, 2.5rem);
  font-weight: 700;
  line-height: 1.15;
  margin: 0 0 10px;
  letter-spacing: -0.01em;
}
.content h2 {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 600;
  margin: 52px 0 16px;
  padding-top: 14px;
  border-top: 1px solid var(--panel-border);
  letter-spacing: -0.005em;
}
.content h3 {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 600;
  margin: 34px 0 12px;
  color: var(--accent-strong);
}
.content h4 {
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 600;
  margin: 24px 0 10px;
  color: var(--text-primary);
}

.content p { margin: 0 0 16px; color: var(--text-secondary); }
.content strong { color: var(--text-primary); font-weight: 600; }
.content em { color: var(--text-primary); font-style: italic; }

.content ul, .content ol { margin: 0 0 18px; padding-left: 22px; color: var(--text-secondary); }
.content li { margin: 6px 0; }
.content li::marker { color: var(--accent-dim); }

.lede {
  font-size: 1.12rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin: 0 0 28px;
}

/* anchor link on headings */
.content h2, .content h3 { position: relative; scroll-margin-top: calc(var(--topbar-h) + 16px); }
.anchor {
  color: var(--accent-dim);
  opacity: 0;
  margin-left: 8px;
  font-weight: 400;
  transition: opacity 0.12s;
}
.content h2:hover .anchor, .content h3:hover .anchor { opacity: 1; }

/* ---------- Inline code ---------- */

.content :not(pre) > code {
  font-family: var(--font-mono);
  font-size: 0.86em;
  background: rgba(157, 184, 207, 0.09);
  color: var(--accent-strong);
  padding: 0.12em 0.42em;
  border-radius: 5px;
  border: 1px solid var(--panel-border);
  white-space: nowrap;
}

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

.code {
  position: relative;
  background: var(--code-bg);
  border: 1px solid var(--code-border);
  border-radius: 10px;
  margin: 0 0 22px;
  overflow: hidden;
}
.code__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 14px;
  border-bottom: 1px solid var(--panel-border);
  background: rgba(157, 184, 207, 0.03);
}
.code__label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
}
.code__copy {
  font-family: var(--font-body);
  font-size: 0.72rem;
  color: var(--text-muted);
  background: none;
  border: 1px solid var(--panel-border);
  border-radius: 6px;
  padding: 3px 9px;
  cursor: pointer;
}
.code__copy:hover { color: var(--text-primary); border-color: var(--panel-border-strong); }
.code pre {
  margin: 0;
  padding: 16px 18px;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.83rem;
  line-height: 1.68;
  scrollbar-width: thin;
  scrollbar-color: var(--accent-dim) transparent;
}
.code pre::-webkit-scrollbar { height: 8px; }
.code pre::-webkit-scrollbar-thumb { background: var(--accent-dim); border-radius: 4px; }
.code code { font-family: var(--font-mono); white-space: pre; }

/* token colors (shared with the highlighter) */
.tok-kw   { color: var(--tok-keyword); }
.tok-type { color: var(--tok-type); }
.tok-str  { color: var(--tok-string); }
.tok-com  { color: var(--tok-comment); font-style: italic; }
.tok-num  { color: var(--tok-num); }
.tok-fn   { color: var(--tok-fn); }
.tok-punct{ color: var(--tok-punct); }
.tok-attr { color: var(--plan); }

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

.callout {
  display: flex;
  gap: 12px;
  padding: 14px 16px;
  border-radius: 10px;
  margin: 0 0 22px;
  font-size: 0.92rem;
  border: 1px solid var(--panel-border);
  background: var(--panel-bg);
}
.callout__icon { flex: none; font-size: 1rem; line-height: 1.5; }
.callout__body { min-width: 0; }
.callout__body > *:last-child { margin-bottom: 0; }
.callout__title { font-family: var(--font-display); font-weight: 600; color: var(--text-primary); display: block; margin-bottom: 3px; font-size: 0.9rem; }
.callout p { margin: 0 0 8px; }

.callout--note    { border-left: 3px solid var(--accent); }
.callout--tip     { border-left: 3px solid var(--ok); }
.callout--warn    { border-left: 3px solid var(--warn); }
.callout--danger  { border-left: 3px solid var(--danger); }
.callout--plan    { border-left: 3px solid var(--plan); }

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

.table-wrap { overflow-x: auto; margin: 0 0 22px; border-radius: 10px; border: 1px solid var(--panel-border); }
.content table {
  border-collapse: collapse;
  width: 100%;
  font-size: 0.86rem;
  min-width: 460px;
}
.content th, .content td {
  text-align: left;
  padding: 9px 14px;
  border-bottom: 1px solid var(--panel-border);
  vertical-align: top;
}
.content th {
  font-family: var(--font-display);
  font-weight: 600;
  color: var(--text-primary);
  background: rgba(157, 184, 207, 0.04);
  font-size: 0.8rem;
  letter-spacing: 0.02em;
}
.content td { color: var(--text-secondary); }
.content tr:last-child td { border-bottom: none; }
.content td code, .content th code {
  background: rgba(157, 184, 207, 0.08);
  color: var(--accent-strong);
  padding: 0.1em 0.36em;
  border-radius: 4px;
  font-size: 0.86em;
  white-space: nowrap;
}

/* ---------- Pills / badges inline ---------- */

.pill {
  display: inline-block;
  font-family: var(--font-display);
  font-size: 0.64rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  padding: 2px 8px;
  border-radius: 999px;
  vertical-align: middle;
  margin-left: 8px;
}
.pill--plan   { color: var(--plan);  background: rgba(183, 159, 224, 0.13); border: 1px solid rgba(183, 159, 224, 0.3); }
.pill--engine { color: var(--ok);    background: rgba(127, 214, 168, 0.11); border: 1px solid rgba(127, 214, 168, 0.28); }
.pill--core   { color: var(--accent);background: rgba(157, 184, 207, 0.1);  border: 1px solid var(--panel-border-strong); }

/* ---------- Cards (hub pages) ---------- */

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 16px;
  margin: 0 0 28px;
}
.doc-card {
  display: block;
  background: rgba(157, 184, 207, 0.03);
  border: 1px solid var(--panel-border);
  border-radius: 12px;
  padding: 20px;
  transition: border-color 0.15s, transform 0.15s, background 0.15s;
}
.doc-card:hover {
  border-color: var(--panel-border-strong);
  background: rgba(157, 184, 207, 0.06);
  transform: translateY(-2px);
}
.doc-card__eyebrow {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.05em;
  color: var(--accent-dim);
  text-transform: uppercase;
}
.doc-card__title {
  font-family: var(--font-display);
  font-size: 1.08rem;
  font-weight: 600;
  color: var(--text-primary);
  margin: 8px 0 6px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.doc-card__title .ic { color: var(--accent); }
.doc-card__desc { font-size: 0.86rem; color: var(--text-secondary); margin: 0; }

/* ---------- Feature key-value grid ---------- */

.kv {
  display: grid;
  grid-template-columns: max-content 1fr;
  gap: 8px 20px;
  margin: 0 0 22px;
  font-size: 0.9rem;
}
.kv dt { font-family: var(--font-mono); color: var(--accent-strong); font-size: 0.85rem; }
.kv dd { margin: 0; color: var(--text-secondary); }

/* ---------- Prev / next nav ---------- */

.pager {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  margin-top: 56px;
  padding-top: 26px;
  border-top: 1px solid var(--panel-border);
}
.pager a {
  flex: 1;
  max-width: 300px;
  padding: 14px 18px;
  border: 1px solid var(--panel-border);
  border-radius: 10px;
  background: rgba(157, 184, 207, 0.03);
}
.pager a:hover { border-color: var(--panel-border-strong); background: rgba(157, 184, 207, 0.06); }
.pager__dir { font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--text-muted); }
.pager__label { font-family: var(--font-display); font-weight: 600; color: var(--text-primary); margin-top: 3px; }
.pager__next { text-align: right; margin-left: auto; }

/* ---------- Steps (tutorial) ---------- */

.step {
  position: relative;
  padding-left: 20px;
  border-left: 2px solid var(--panel-border);
  margin: 0 0 8px;
}

/* ---------- Hero (hub) ---------- */

.doc-hero {
  padding: 8px 0 26px;
  border-bottom: 1px solid var(--panel-border);
  margin-bottom: 34px;
}
.doc-hero .eyebrow {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-muted);
  letter-spacing: 0.05em;
  margin: 0 0 12px;
}

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

.doc-footer {
  border-top: 1px solid var(--panel-border);
  padding: 26px 40px;
  color: var(--text-muted);
  font-size: 0.82rem;
  text-align: center;
}

/* ---------- Backdrop for mobile drawer ---------- */
.scrim {
  display: none;
  position: fixed;
  inset: var(--topbar-h) 0 0;
  background: rgba(4, 8, 12, 0.6);
  backdrop-filter: blur(2px);
  z-index: 25;
}

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

@media (max-width: 1080px) {
  .main { grid-template-columns: minmax(0, 1fr); }
  .toc { display: none; }
}

@media (max-width: 820px) {
  .shell { grid-template-columns: minmax(0, 1fr); }
  .menu-toggle { display: inline-flex; }
  .sidebar {
    position: fixed;
    top: var(--topbar-h);
    left: 0;
    width: 280px;
    max-width: 84vw;
    background: var(--panel-bg);
    transform: translateX(-102%);
    transition: transform 0.2s ease;
    z-index: 30;
    box-shadow: 0 0 40px rgba(0, 0, 0, 0.5);
  }
  body.nav-open .sidebar { transform: translateX(0); }
  body.nav-open .scrim { display: block; }
  .main { padding: 30px 22px 100px; }
  .topbar__nav { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .doc-card, .sidebar { transition: none; }
}