/* --- theme tokens: light is the base; dark applies on explicit toggle
       (data-theme="dark") or on a dark OS when no explicit choice is set --- */
:root {
  color-scheme: light;
  --bg: #f6f6f4;
  --card: #ffffff;
  --edge: #e4e2dc;
  --fg: #1f2328;
  --muted: #5f6670;
  --accent: #4a4f57;
  --accent2: #4550d8;
  --ok: #1f9d63;
  --err: #d64545;
  --code-bg: #f2f0ec;
  --nav-bg: rgba(246, 246, 244, 0.9);
  --role-ai: #2563a8;
  --role-dist: #6d4b9e;
  --role-infra: #a86a00;
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0f1117;
  --card: #171a23;
  --edge: #242835;
  --fg: #e6e8ee;
  --muted: #9aa2b1;
  --accent: #e5a00d;
  --accent2: #5865f2;
  --ok: #2ec27e;
  --err: #ff6b6b;
  --code-bg: #0d0f15;
  --nav-bg: rgba(15, 17, 23, 0.9);
  --role-ai: #5c9ce6;
  --role-dist: #b18ce0;
  --role-infra: #e5a00d;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    color-scheme: dark;
    --bg: #0f1117;
    --card: #171a23;
    --edge: #242835;
    --fg: #e6e8ee;
    --muted: #9aa2b1;
    --accent: #e5a00d;
    --accent2: #5865f2;
    --ok: #2ec27e;
    --err: #ff6b6b;
    --code-bg: #0d0f15;
    --nav-bg: rgba(15, 17, 23, 0.9);
    --role-ai: #5c9ce6;
    --role-dist: #b18ce0;
    --role-infra: #e5a00d;
  }
}

/* architecture-map palette tokens (theme-aware; maps reference these via var()) */
:root {
  --m-node:#ffffff;--m-chip:#f2f0ea;--m-zone:#f6f5f2;--m-zone-bd:#ece9e3;
  --m-node-bd:#d8d4cc;--m-chip-bd:#ddd8ce;--m-panel-bd:#e6e1d8;--m-line:#c3beb4;
  --m-name:#1f2328;--m-desc:#6b7280;--m-dim:#8b8378;--m-label:#8b8378;--m-body:#5a5f68;
  --m-blue:#2563a8;--m-purple:#6d4b9e;--m-green:#2f8f7a;--m-green2:#2e8f7c;--m-code:#217a68;
  --m-arm-bd:#8a6bb5;--m-amber:#a86a00;--m-tan:#8a6d2e;--m-warn:#a85a38;
  --m-gate:#fbf3e0;--m-gate-bd:#e6d8b8;--m-sand-bd:#d6e8e0;--m-live-bd:#d4e2f0;
}
:root[data-theme="dark"] {
  --m-node:#161a20;--m-chip:#1b2028;--m-zone:#1a1e24;--m-zone-bd:#262b32;
  --m-node-bd:#333a43;--m-chip-bd:#3a4250;--m-panel-bd:#2c323b;--m-line:#454d59;
  --m-name:#e7eaef;--m-desc:#98a1b0;--m-dim:#767d8a;--m-label:#8a9250;--m-body:#c3cad6;
  --m-blue:#5c9ce6;--m-purple:#b18ce0;--m-green:#46b39d;--m-green2:#5fc2ad;--m-code:#8fd6c4;
  --m-arm-bd:#7d6b9e;--m-amber:#e6b357;--m-tan:#c9b071;--m-warn:#c98a6a;
  --m-gate:#1b170e;--m-gate-bd:#5c4a24;--m-sand-bd:#2f5148;--m-live-bd:#2b4a63;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --m-node:#161a20;--m-chip:#1b2028;--m-zone:#1a1e24;--m-zone-bd:#262b32;
    --m-node-bd:#333a43;--m-chip-bd:#3a4250;--m-panel-bd:#2c323b;--m-line:#454d59;
    --m-name:#e7eaef;--m-desc:#98a1b0;--m-dim:#767d8a;--m-label:#8a9250;--m-body:#c3cad6;
    --m-blue:#5c9ce6;--m-purple:#b18ce0;--m-green:#46b39d;--m-green2:#5fc2ad;--m-code:#8fd6c4;
    --m-arm-bd:#7d6b9e;--m-amber:#e6b357;--m-tan:#c9b071;--m-warn:#c98a6a;
    --m-gate:#1b170e;--m-gate-bd:#5c4a24;--m-sand-bd:#2f5148;--m-live-bd:#2b4a63;
  }
}

/* link color, decoupled from the gold brand accent (gold read muddy on light) */
:root { --link: #2563a8; }
:root[data-theme="dark"] { --link: #5c9ce6; }
@media (prefers-color-scheme: dark) { :root:not([data-theme]) { --link: #5c9ce6; } }

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.55 -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  transition: background-color .2s ease, color .2s ease;
}

a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; }

/* --- top nav bar (multi-page) ------------------------------------------- */

nav.top {
  border-bottom: 1px solid var(--edge);
  background: var(--nav-bg);
  backdrop-filter: blur(6px);
  position: sticky;
  top: 0;
  z-index: 10;
}
nav.top .inner {
  max-width: 860px;
  margin: 0 auto;
  padding: 12px 20px;
  display: flex;
  align-items: center;
  gap: 18px;
  flex-wrap: wrap;
}
nav.top .brand {
  font-weight: 700;
  color: var(--fg);
  font-size: 1.05rem;
}
nav.top .brand span { color: var(--accent); }
nav.top ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  font-size: 0.92rem;
}
nav.top ul a { color: var(--muted); }
nav.top ul a:hover, nav.top ul a.active { color: var(--fg); text-decoration: none; }

/* theme toggle (light/dark, viewer choice) */
.theme-toggle {
  margin-left: auto;
  background: none;
  border: 1px solid var(--edge);
  color: var(--muted);
  border-radius: 99px;
  width: 34px;
  height: 34px;
  min-width: 34px;
  cursor: pointer;
  font-size: 15px;
  line-height: 1;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0;
}
.theme-toggle:hover { color: var(--fg); border-color: var(--muted); }
.theme-toggle::before { content: "\263E"; }                     /* light mode shows a moon (click for dark) */
:root[data-theme="dark"] .theme-toggle::before { content: "\2600"; }  /* dark mode shows a sun (click for light) */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) .theme-toggle::before { content: "\2600"; }
}

/* --- layout ------------------------------------------------------------- */

.wrap {
  max-width: 860px;
  margin: 0 auto;
  padding: 28px 20px 72px;
}
.wrap.narrow { max-width: 700px; }

/* --- headings ----------------------------------------------------------- */

h1 { font-size: 2rem; margin: 0 0 6px; line-height: 1.2; }
h2 { font-size: 1.35rem; margin: 32px 0 10px; line-height: 1.25; }
h3 { font-size: 1.08rem; margin: 20px 0 6px; color: var(--fg); }
.sub { color: var(--muted); margin: 0 0 24px; font-size: 1rem; }

/* --- prose -------------------------------------------------------------- */

p { margin: 0 0 14px; }
ul, ol { padding-left: 22px; margin: 0 0 14px; }
li { margin: 0 0 6px; }
hr { border: 0; border-top: 1px solid var(--edge); margin: 28px 0; }

blockquote {
  border-left: 3px solid var(--accent);
  margin: 16px 0;
  padding: 4px 0 4px 14px;
  color: var(--muted);
  font-style: italic;
}

/* --- cards -------------------------------------------------------------- */

.card {
  background: var(--card);
  border: 1px solid var(--edge);
  border-radius: 14px;
  padding: 20px;
  margin: 14px 0;
}
.card h3 { margin-top: 0; }

/* --- featured work grid (landing page) ---------------------------------- */

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 14px;
  margin: 20px 0 32px;
}
.grid .card {
  margin: 0;
  transition: border-color .15s ease;
}
.grid .card:hover { border-color: var(--accent); }
.grid .card h3 { font-size: 1rem; }
.grid .card p { color: var(--muted); font-size: 0.92rem; margin-bottom: 0; }
.grid .card a.card-link {
  color: var(--fg);
  display: block;
}
.grid .card a.card-link:hover { text-decoration: none; }

/* --- landing: headline metrics strip --------------------------------------- */

.stats {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 20px 0 30px;
}
.stat {
  flex: 1 1 130px;
  background: var(--card);
  border: 1px solid var(--edge);
  border-radius: 12px;
  padding: 13px 15px;
}
.stat b {
  display: block;
  font-size: 1.4rem;
  line-height: 1.1;
  color: var(--fg);
  font-variant-numeric: tabular-nums;
}
.stat span {
  display: block;
  margin-top: 3px;
  font-size: 0.8rem;
  color: var(--muted);
}

/* --- landing: role-colored band headings ----------------------------------- */

h2.band {
  border-left: 3px solid var(--edge);
  padding-left: 11px;
}
h2.band-ai { border-left-color: var(--role-ai); }
h2.band-dist { border-left-color: var(--role-dist); }
h2.band-infra { border-left-color: var(--role-infra); }

/* --- pills & tags ------------------------------------------------------- */

.pill {
  display: inline-block;
  font-size: 0.72rem;
  padding: 2px 8px;
  border-radius: 99px;
  background: var(--code-bg);
  border: 1px solid var(--edge);
  color: var(--muted);
  margin-right: 6px;
}
.pill.ok { color: var(--ok); border-color: var(--ok); }
.pill.accent { color: var(--accent); border-color: var(--accent); }

/* --- progressive disclosure --------------------------------------------- */

details.more {
  background: var(--code-bg);
  border: 1px solid var(--edge);
  border-radius: 10px;
  padding: 12px 14px;
  margin: 12px 0;
}
details.more[open] { padding-bottom: 14px; }
details.more > summary {
  cursor: pointer;
  color: var(--link);
  font-weight: 600;
  font-size: 0.95rem;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 8px;
}
details.more > summary::before {
  content: "▸";
  transition: transform .15s ease;
  color: var(--link);
  font-size: 0.85rem;
}
details.more[open] > summary::before { transform: rotate(90deg); }
details.more > summary::-webkit-details-marker { display: none; }
details.more > *:not(summary) { margin-top: 10px; }

/* --- code + tables ----------------------------------------------------- */

code {
  background: var(--code-bg);
  padding: 1px 6px;
  border-radius: 6px;
  border: 1px solid var(--edge);
  font-family: "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.88em;
}
pre {
  background: var(--code-bg);
  border: 1px solid var(--edge);
  border-radius: 10px;
  padding: 14px 16px;
  overflow-x: auto;
  font-family: "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.86rem;
  line-height: 1.5;
}
pre code {
  background: transparent;
  padding: 0;
  border: 0;
  border-radius: 0;
  font-size: 1em;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
  margin: 12px 0 18px;
}
th, td {
  text-align: left;
  padding: 9px 10px;
  border-bottom: 1px solid var(--edge);
  vertical-align: top;
}
th { color: var(--muted); font-weight: 600; font-size: 0.82rem; text-transform: uppercase; letter-spacing: .04em; }

/* --- diagrams / figures ------------------------------------------------- */

figure {
  margin: 18px 0;
  text-align: center;
}
figure img, figure svg {
  max-width: 100%;
  height: auto;
  border: 1px solid var(--edge);
  border-radius: 10px;
  background: var(--code-bg);
}
figcaption {
  color: var(--muted);
  font-size: 0.85rem;
  font-style: italic;
  margin-top: 8px;
}

/* --- footer ------------------------------------------------------------- */

footer.site {
  border-top: 1px solid var(--edge);
  margin-top: 48px;
  padding: 20px 0;
  color: var(--muted);
  font-size: 0.85rem;
  text-align: center;
}
footer.site a { color: var(--muted); text-decoration: underline; }

/* --- utility ------------------------------------------------------------ */

.muted { color: var(--muted); }
.center { text-align: center; }
.small { font-size: 0.88rem; }

@media (max-width: 560px) {
  h1 { font-size: 1.6rem; }
  h2 { font-size: 1.2rem; }
  .wrap { padding: 20px 16px 56px; }
  nav.top .inner { padding: 10px 16px; gap: 12px; }
  nav.top ul { gap: 10px; }
}

/* ============================================================
   UNIFIED SHELL — shared fonts, header, menu (TOC), across every page
   ============================================================ */

:root {
  --f-display: "Sora", system-ui, sans-serif;
  --f-mono: "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  --f-body: "IBM Plex Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
}
body { font-family: var(--f-body); }
h1, h2, h3, h4 { font-family: var(--f-display); letter-spacing: -0.01em; }
code, pre, .pill, .mono { font-family: var(--f-mono); }

@keyframes cblink { 50% { opacity: 0; } }

/* --- sticky site header --- */
.site-nav {
  position: sticky; top: 0; z-index: 30;
  background: var(--nav-bg); backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--edge);
}
.site-nav .nav-in {
  max-width: 960px; margin: 0 auto; padding: 13px 22px;
  display: flex; align-items: center; gap: 18px;
}
.site-nav .brand {
  font-family: var(--f-mono); font-weight: 600; font-size: 15px;
  color: var(--fg); letter-spacing: 0.01em;
}
.site-nav .brand .cur { color: var(--accent); animation: cblink 1.1s steps(1) infinite; }
.site-nav .nav-links { display: flex; gap: 16px; font-family: var(--f-mono); font-size: 13px; }
.site-nav .nav-links a { color: var(--muted); }
.site-nav .nav-links a:hover { color: var(--fg); text-decoration: none; }
.site-nav .nav-tools { margin-left: auto; display: flex; align-items: center; gap: 10px; }
.menu-btn {
  font-family: var(--f-mono); font-size: 13px;
  background: none; border: 1px solid var(--edge); color: var(--muted);
  border-radius: 8px; padding: 5px 13px; cursor: pointer;
}
.menu-btn:hover { color: var(--fg); border-color: var(--muted); }
@media (max-width: 620px) { .site-nav .nav-links { display: none; } }

/* --- full-screen menu overlay = the table of contents --- */
.sitemenu {
  position: fixed; inset: 0; z-index: 50; overflow-y: auto;
  background: var(--bg); opacity: 0; transition: opacity 0.2s ease;
}
.sitemenu.on { opacity: 1; }
.sitemenu .menu-in { max-width: 960px; margin: 0 auto; padding: 20px 22px 50px; }
.sitemenu .menu-head {
  display: flex; align-items: center; justify-content: space-between;
  padding: 4px 0 16px; border-bottom: 1px solid var(--edge); margin-bottom: 24px;
  position: sticky; top: 0; background: var(--bg);
}
.sitemenu .menu-home { font-family: var(--f-mono); font-weight: 600; color: var(--fg); font-size: 15px; }
.sitemenu .menu-home .cur { color: var(--accent); }
.menu-close {
  font-family: var(--f-mono); font-size: 13px;
  background: none; border: 1px solid var(--edge); color: var(--muted);
  border-radius: 8px; padding: 5px 13px; cursor: pointer;
}
.menu-close:hover { color: var(--fg); border-color: var(--muted); }
.menu-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)); gap: 24px 30px; }
.menu-grid section h4 {
  font-family: var(--f-mono); font-size: 0.7rem; letter-spacing: 0.13em; text-transform: uppercase;
  color: var(--accent); margin: 0 0 6px; padding-bottom: 9px; border-bottom: 1px solid var(--edge);
}
.menu-grid section a { display: block; padding: 7px 0; color: var(--fg); font-size: 0.95rem; }
.menu-grid section a:hover { color: var(--link); text-decoration: none; }

.foot-name { color: var(--fg); font-weight: 700; font-family: var(--f-display); }