/* CLIO Core site. Editorial field-guide styling shared with the Clio family:
   black and warm ivory, cyan accent, copper secondary, Newsreader headings,
   IBM Plex for interface and code. Colors are only used through the semantic
   variables defined in :root and [data-theme="light"]. */

@font-face { font-family: "IBM Plex Sans"; font-style: normal; font-weight: 100 700; font-display: swap; src: url("../fonts/plex-sans.woff2") format("woff2"); }
@font-face { font-family: "IBM Plex Mono"; font-style: normal; font-weight: 400; font-display: swap; src: url("../fonts/plex-400.woff2") format("woff2"); }
@font-face { font-family: "IBM Plex Mono"; font-style: normal; font-weight: 500; font-display: swap; src: url("../fonts/plex-500.woff2") format("woff2"); }
@font-face { font-family: "Newsreader"; font-style: normal; font-weight: 500; font-display: swap; src: url("../fonts/news-normal-500.woff2") format("woff2"); }
@font-face { font-family: "Newsreader"; font-style: italic; font-weight: 480; font-display: swap; src: url("../fonts/news-italic-480.woff2") format("woff2"); }

:root {
  color-scheme: dark;
  --paper: #000000;
  --paper-raised: #0d0d0c;
  --paper-sunk: #151412;
  --ink: #f0ece1;
  --ink-soft: #d6cebf;
  --muted: #a3998a;
  --line: #23211d;
  --line-control: #736a5f;
  --accent: #00d4db;
  --accent-soft: #052629;
  --on-accent: #000000;
  --secondary: #ee852f;
  --good: #7fd39b;
  --code-paper: #0d0d0c;
  --code-ink: #f0ece1;
  --code-line: #23211d;

  --font-ui: "IBM Plex Sans", system-ui, sans-serif;
  --font-display: "Newsreader", Georgia, serif;
  --font-mono: "IBM Plex Mono", ui-monospace, "Cascadia Code", Consolas, monospace;

  --space-1: 0.25rem; --space-2: 0.5rem; --space-3: 0.75rem; --space-4: 1rem;
  --space-5: 1.5rem; --space-6: 2rem; --space-7: 3rem; --space-8: 4.5rem; --space-9: 7rem;
  --radius-sm: 2px;
  --radius: 4px;
  --page: 1240px;
  --measure: 72ch;
  --header-h: 60px;

  --motion-fast: 160ms;
  --motion-base: 240ms;
  --motion-enter: 640ms;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

[data-theme="light"] {
  color-scheme: light;
  --paper: #f3eee4;
  --paper-raised: #faf7f2;
  --paper-sunk: #e9e2d5;
  --ink: #1a1612;
  --ink-soft: #3c342c;
  --muted: #524a42;
  --line: #d4cbbd;
  --line-control: #756c5e;
  --accent: #0a666c;
  --accent-soft: #e3f2f3;
  --on-accent: #faf7f2;
  --secondary: #9a4812;
  --good: #1f7a44;
  /* Code keeps a dark surface in both themes. */
  --code-paper: #151412;
  --code-ink: #f0ece1;
  --code-line: #2e2b26;
}

/* ---------- Base ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-padding-top: calc(var(--header-h) + var(--space-4)); }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-ui);
  font-size: clamp(1rem, 0.96rem + 0.2vw, 1.0625rem);
  line-height: 1.65;
  transition: background-color var(--motion-base) var(--ease), color var(--motion-base) var(--ease);
}
img, svg, video { max-width: 100%; height: auto; }
a { color: var(--accent); text-underline-offset: 0.18em; text-decoration-thickness: 1px; }
a:hover { text-decoration-thickness: 2px; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: var(--radius-sm); }
::selection { background: var(--accent); color: var(--on-accent); }

h1, h2, h3, h4 { font-family: var(--font-display); font-weight: 500; line-height: 1.12; letter-spacing: -0.01em; margin: 0; color: var(--ink); }
h1 em, h2 em, h3 em { font-style: italic; font-weight: 480; color: var(--accent); }
h1 { font-size: clamp(2.3rem, 1.6rem + 3.2vw, 4.4rem); }
h2 { font-size: clamp(1.7rem, 1.35rem + 1.4vw, 2.5rem); }
h3 { font-size: clamp(1.25rem, 1.12rem + 0.5vw, 1.5rem); }
h4 { font-family: var(--font-ui); font-size: 1rem; font-weight: 600; letter-spacing: 0; }
p { margin: 0 0 var(--space-4); }
ul, ol { padding-inline-start: 1.25rem; margin: 0 0 var(--space-4); }
li { margin-block: 0.3rem; }
li::marker { color: var(--muted); }
strong { font-weight: 600; color: var(--ink); }
hr { border: 0; border-top: 1px solid var(--line); margin: var(--space-7) 0; }

code, kbd, samp, pre { font-family: var(--font-mono); font-size: 0.9em; }
:not(pre) > code {
  background: var(--paper-sunk);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 0.05em 0.35em;
  overflow-wrap: anywhere;
}
kbd { border: 1px solid var(--line-control); border-bottom-width: 2px; border-radius: var(--radius-sm); padding: 0 0.35em; font-size: 0.85em; }

.skip { position: absolute; left: var(--space-4); top: -100px; background: var(--accent); color: var(--on-accent); padding: var(--space-2) var(--space-4); z-index: 100; border-radius: var(--radius-sm); }
.skip:focus { top: var(--space-2); }

.eyebrow {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--secondary);
  margin: 0 0 var(--space-3);
}
.eyebrow .chapter { color: var(--muted); }
.lede { font-size: clamp(1.1rem, 1rem + 0.45vw, 1.3rem); color: var(--ink-soft); line-height: 1.55; max-width: 62ch; }
.muted { color: var(--muted); }
.tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--secondary);
  border: 1px solid currentColor;
  border-radius: var(--radius-sm);
  padding: 0.02rem 0.4rem;
  vertical-align: 0.15em;
  line-height: 1.5;
}
.tag.accent { color: var(--accent); }

.text-link { font-weight: 500; text-decoration: none; display: inline-flex; gap: 0.4em; align-items: baseline; }
.text-link span[aria-hidden] { transition: transform var(--motion-fast) var(--ease); }
.text-link:hover span[aria-hidden] { transform: translateX(3px); }

.btn {
  display: inline-flex; align-items: center; gap: 0.5em;
  background: var(--accent); color: var(--on-accent);
  border: 1px solid var(--accent); border-radius: var(--radius-sm);
  padding: 0.7rem 1.15rem; font-weight: 600; text-decoration: none;
  min-height: 44px;
  transition: filter var(--motion-fast) var(--ease);
}
.btn:hover { filter: brightness(1.1); }
.btn.ghost { background: transparent; color: var(--ink); border-color: var(--line-control); }
.btn.ghost:hover { border-color: var(--accent); color: var(--accent); filter: none; }
.actions { display: flex; flex-wrap: wrap; gap: var(--space-3) var(--space-5); align-items: center; margin-top: var(--space-5); }

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.header-inner {
  max-width: var(--page); margin: 0 auto; height: var(--header-h);
  display: flex; align-items: center; gap: var(--space-5);
  padding: 0 var(--space-5);
}
.brand { display: inline-flex; align-items: center; gap: 0.6rem; text-decoration: none; color: var(--ink); flex-shrink: 0; }
.brand img { width: 30px; height: 30px; }
.brand-name { font-family: var(--font-display); font-size: 1.3rem; letter-spacing: -0.01em; }
.brand-name em { font-style: italic; color: var(--accent); font-weight: 480; }
.brand .mark-light { display: none; }
[data-theme="light"] .brand .mark-dark { display: none; }
[data-theme="light"] .brand .mark-light { display: inline; }

.primary-nav { display: flex; gap: var(--space-1); margin-inline-start: auto; }
.primary-nav a {
  color: var(--ink-soft); text-decoration: none; font-size: 0.95rem;
  padding: 0.45rem 0.7rem; border-radius: var(--radius-sm);
  transition: color var(--motion-fast) var(--ease), background-color var(--motion-fast) var(--ease);
}
.primary-nav a:hover { color: var(--ink); background: var(--paper-sunk); }
.primary-nav a[aria-current="page"] { color: var(--accent); box-shadow: inset 0 -2px 0 var(--accent); border-radius: 0; }
.header-tools { display: flex; align-items: center; gap: var(--space-2); }
.icon-btn {
  display: inline-grid; place-items: center; width: 38px; height: 38px;
  background: transparent; color: var(--ink-soft);
  border: 1px solid var(--line); border-radius: var(--radius-sm); cursor: pointer;
  text-decoration: none;
  transition: color var(--motion-fast) var(--ease), border-color var(--motion-fast) var(--ease);
}
.icon-btn:hover { color: var(--accent); border-color: var(--accent); }
.icon-btn svg { width: 18px; height: 18px; fill: none; stroke: currentColor; stroke-width: 1.6; stroke-linecap: round; stroke-linejoin: round; }
.icon-btn svg.filled { fill: currentColor; stroke: none; }
.theme-toggle .sun { display: none; }
[data-theme="light"] .theme-toggle .sun { display: block; }
[data-theme="light"] .theme-toggle .moon { display: none; }
.menu-toggle { display: none; }

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--line); margin-top: var(--space-9); }
.footer-inner {
  max-width: var(--page); margin: 0 auto; padding: var(--space-7) var(--space-5) var(--space-6);
  display: grid; grid-template-columns: 1.4fr repeat(3, 1fr); gap: var(--space-6);
}
.footer-inner h2 { font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); margin-bottom: var(--space-3); font-weight: 500; }
.footer-inner ul { list-style: none; padding: 0; margin: 0; }
.footer-inner li { margin: 0.35rem 0; }
.footer-inner a { color: var(--ink-soft); text-decoration: none; font-size: 0.93rem; }
.footer-inner a:hover { color: var(--accent); }
.footer-brand p { color: var(--muted); font-size: 0.93rem; max-width: 36ch; margin-top: var(--space-3); }
.footer-legal {
  max-width: var(--page); margin: 0 auto; padding: var(--space-4) var(--space-5) var(--space-6);
  display: flex; flex-wrap: wrap; justify-content: space-between; gap: var(--space-3);
  color: var(--muted); font-size: 0.85rem; border-top: 1px solid var(--line);
}
.footer-legal a { color: var(--muted); }

/* ---------- Code blocks ---------- */
.code {
  position: relative;
  margin: var(--space-5) 0;
  background: var(--code-paper);
  border: 1px solid var(--code-line);
  border-radius: var(--radius);
  color: var(--code-ink);
}
.code-label {
  display: flex; justify-content: space-between; align-items: center; gap: var(--space-3);
  font-family: var(--font-mono); font-size: 0.74rem; letter-spacing: 0.04em;
  color: #a3998a; padding: 0.4rem 0.5rem 0.4rem 1rem;
  border-bottom: 1px solid var(--code-line);
  min-height: 40px;
}
.code pre { margin: 0; padding: 1rem 1.1rem; overflow-x: auto; line-height: 1.6; font-size: 0.86rem; tab-size: 2; }
.code pre code { color: inherit; }
.code:not(:has(.code-label)) pre { padding-inline-end: 4.5rem; }
.copy {
  font-family: var(--font-mono); font-size: 0.72rem; letter-spacing: 0.04em;
  background: transparent; color: #d6cebf;
  border: 1px solid #3a3631; border-radius: var(--radius-sm);
  padding: 0.25rem 0.6rem; cursor: pointer; min-height: 30px;
  transition: color var(--motion-fast) var(--ease), border-color var(--motion-fast) var(--ease);
}
.copy:hover { color: #00d4db; border-color: #00d4db; }
.copy[data-state="done"] { color: #7fd39b; border-color: #7fd39b; }
.code > .copy { position: absolute; top: 0.55rem; right: 0.55rem; }
pre .c { color: #8f877b; font-style: italic; }   /* comment */
pre .p { color: #736a5f; user-select: none; }   /* prompt */
pre .k { color: #00d4db; }                       /* keyword / key */
pre .s { color: #e8b58a; }                       /* string */
pre .n { color: #ee852f; }                       /* number / emphasis */
pre .o { color: #a3998a; }                       /* output */

/* ---------- Tabs (progressive) ---------- */
.tabs { margin: var(--space-5) 0; }
.tab-list { display: flex; flex-wrap: wrap; gap: 0; border-bottom: 1px solid var(--line); margin-bottom: var(--space-4); }
.tab-list button {
  font: inherit; font-size: 0.92rem; background: none; border: 0; color: var(--muted);
  padding: 0.6rem 1rem; cursor: pointer; border-bottom: 2px solid transparent; margin-bottom: -1px;
  min-height: 44px;
}
.tab-list button:hover { color: var(--ink); }
.tab-list button[aria-selected="true"] { color: var(--accent); border-bottom-color: var(--accent); }
.tabs.enhanced .tab-panel[hidden] { display: none; }
.tab-panel > .tab-title { font-family: var(--font-mono); font-size: 0.8rem; color: var(--secondary); text-transform: uppercase; letter-spacing: 0.06em; }
.tabs.enhanced .tab-panel > .tab-title { display: none; }

/* Picker: the tab buttons become a grid of choices with a one-line note. */
.tabs.picker > .tab-list {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(10.5rem, 1fr));
  gap: var(--space-2); border-bottom: 0; margin-bottom: var(--space-5);
}
.tabs.picker > .tab-list button {
  display: flex; flex-direction: column; align-items: flex-start; gap: 0.2rem; text-align: left;
  border: 1px solid var(--line); border-radius: var(--radius); margin: 0; padding: 0.75rem 0.9rem;
  background: var(--paper-raised); color: var(--ink);
}
.tabs.picker > .tab-list button:hover { border-color: var(--muted); }
.tabs.picker > .tab-list button[aria-selected="true"] { border-color: var(--accent); box-shadow: inset 0 0 0 1px var(--accent); }
.tabs.picker .tab-name { font-family: var(--font-mono); font-size: 0.95rem; }
.tabs.picker button[aria-selected="true"] .tab-name { color: var(--accent); }
.tabs.picker .tab-note { font-size: 0.8rem; color: var(--muted); line-height: 1.35; }
.tabs.picker > .tab-panel > h3:first-of-type { margin-top: 0; }

/* ---------- Callouts, steps, tables ---------- */
.callout {
  border-inline-start: 2px solid var(--accent);
  background: var(--accent-soft);
  padding: var(--space-4) var(--space-5);
  margin: var(--space-5) 0;
  border-radius: 0 var(--radius) var(--radius) 0;
}
.callout > :last-child { margin-bottom: 0; }
.callout .callout-title { font-family: var(--font-mono); font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--accent); margin-bottom: var(--space-2); display: block; }
.callout.warn { border-color: var(--secondary); background: var(--paper-sunk); }
.callout.warn .callout-title { color: var(--secondary); }

ol.steps { list-style: none; padding: 0; counter-reset: step; margin: var(--space-5) 0; border-inline-start: 1px solid var(--line); }
ol.steps > li { counter-increment: step; position: relative; padding: 0 0 var(--space-5) var(--space-6); margin: 0; }
ol.steps > li::before {
  content: counter(step, decimal-leading-zero);
  position: absolute; left: -1.05rem; top: 0.1rem;
  width: 2.1rem; text-align: center;
  font-family: var(--font-mono); font-size: 0.78rem; color: var(--secondary);
  background: var(--paper); padding: 0.1rem 0;
}
ol.steps > li > h3, ol.steps > li > h4 { margin-bottom: var(--space-2); }

ul.checks { list-style: none; padding: 0; }
ul.checks li { padding-inline-start: 1.6rem; position: relative; }
ul.checks li::before { content: "✓"; position: absolute; left: 0; color: var(--accent); font-weight: 700; }

.table-wrap { overflow-x: auto; margin: var(--space-5) 0; border: 1px solid var(--line); border-radius: var(--radius); }
table { width: 100%; border-collapse: collapse; font-size: 0.92rem; }
th, td { text-align: left; padding: 0.65rem 0.9rem; border-bottom: 1px solid var(--line); vertical-align: top; }
tr:last-child td { border-bottom: 0; }
th { font-family: var(--font-mono); font-weight: 500; font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--muted); background: var(--paper-raised); }
td:first-child { color: var(--ink); font-weight: 500; }
td code { overflow-wrap: normal; white-space: nowrap; }
td:not(:first-child) code { white-space: normal; overflow-wrap: anywhere; }
td.good { color: var(--good); }
td.cost { color: var(--secondary); }

dl.facts { display: flex; flex-wrap: wrap; gap: var(--space-4) var(--space-7); margin: var(--space-5) 0 0; padding: var(--space-4) 0 0; border-top: 1px solid var(--line); }
dl.facts dt { font-family: var(--font-mono); font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--muted); }
dl.facts dd { margin: 0.15rem 0 0; font-size: 0.95rem; color: var(--ink-soft); }

/* Figures and diagrams (used by Design pages). */
figure { margin: var(--space-6) 0; }
figcaption { color: var(--muted); font-size: 0.9rem; margin-top: var(--space-3); }
figure.diagram { border: 1px solid var(--line); border-radius: var(--radius); padding: var(--space-4); background: var(--paper-raised); }
figure.diagram svg { width: 100%; display: block; }
.diagram .box { fill: var(--paper); stroke: var(--line-control); stroke-width: 1.3; }
.diagram .box.hl { stroke: var(--accent); }
.diagram .box.alt { stroke: var(--secondary); }
.diagram text { fill: var(--ink); font-family: var(--font-ui); font-size: 13px; }
.diagram text.muted { fill: var(--muted); font-size: 11.5px; }
.diagram text.title { font-weight: 600; font-size: 14px; }
.diagram .edge { stroke: var(--muted); stroke-width: 1.3; fill: none; }
.diagram .edge.hl { stroke: var(--accent); }
.diagram .arrowhead { fill: var(--muted); }
table.tradeoffs td:first-child { white-space: nowrap; color: var(--accent); }

/* ---------- Guide layout (Docs, Tutorials, Design) ---------- */
.guide {
  max-width: var(--page); margin: 0 auto; padding: var(--space-7) var(--space-5) 0;
  display: grid; grid-template-columns: 220px minmax(0, 1fr) 200px; gap: var(--space-7);
  align-items: start;
}
.side-nav, .page-toc { position: sticky; top: calc(var(--header-h) + var(--space-5)); max-height: calc(100vh - var(--header-h) - var(--space-6)); overflow-y: auto; font-size: 0.9rem; }
.side-nav h2, .page-toc h2 { font-family: var(--font-mono); font-size: 0.72rem; font-weight: 500; text-transform: uppercase; letter-spacing: 0.08em; color: var(--muted); margin: var(--space-5) 0 var(--space-2); }
.side-nav h2:first-child, .page-toc h2:first-child { margin-top: 0; }
.side-nav ul, .page-toc ul { list-style: none; padding: 0; margin: 0; }
.side-nav li, .page-toc li { margin: 0; }
.side-nav a, .page-toc a {
  display: block; color: var(--ink-soft); text-decoration: none; padding: 0.3rem 0 0.3rem 0.8rem;
  border-inline-start: 1px solid var(--line); line-height: 1.35;
  transition: color var(--motion-fast) var(--ease), border-color var(--motion-fast) var(--ease);
}
.side-nav a:hover, .page-toc a:hover { color: var(--ink); border-color: var(--line-control); }
.side-nav a[aria-current="page"] { color: var(--accent); border-color: var(--accent); }
.page-toc a.active { color: var(--accent); border-color: var(--accent); }
.page-toc li.sub a { padding-inline-start: 1.6rem; font-size: 0.85rem; }
.side-nav details summary { display: none; }

.article { min-width: 0; }
.article > header { padding-bottom: var(--space-6); margin-bottom: var(--space-6); border-bottom: 1px solid var(--line); }
.article > header h1 { font-size: clamp(2.1rem, 1.6rem + 2.2vw, 3.4rem); margin-bottom: var(--space-4); }
.prose { max-width: var(--measure); }
.prose h2 { margin: var(--space-8) 0 var(--space-4); padding-top: var(--space-5); border-top: 1px solid var(--line); }
.prose h2:first-child { margin-top: 0; border-top: 0; padding-top: 0; }
.prose h3 { margin: var(--space-6) 0 var(--space-3); }
.prose h4 { margin: var(--space-5) 0 var(--space-2); }
.prose .code, .prose figure, .prose .table-wrap, .prose .wide { max-width: none; }
.prose > .code, .prose > figure, .prose > .table-wrap, .prose > .tabs { width: min(100%, calc(var(--measure) + 12rem)); max-width: 100%; }

.card-list { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 0; border-top: 1px solid var(--line); margin: var(--space-5) 0; }
.card-list a {
  display: block; padding: var(--space-5) var(--space-5) var(--space-5) 0; text-decoration: none; color: var(--ink);
  border-bottom: 1px solid var(--line);
}
.card-list a:hover h3 { color: var(--accent); }
.card-list h3 { font-size: 1.3rem; margin: var(--space-2) 0; transition: color var(--motion-fast) var(--ease); }
.card-list p { color: var(--ink-soft); font-size: 0.95rem; margin: 0; }
.card-list .feature-index { font-family: var(--font-mono); font-size: 0.75rem; color: var(--secondary); }

.page-nav { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-4); margin-top: var(--space-8); padding-top: var(--space-5); border-top: 1px solid var(--line); max-width: var(--measure); }
.page-nav a { text-decoration: none; display: block; padding: var(--space-3) 0; }
.page-nav .dir { display: block; font-family: var(--font-mono); font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--muted); }
.page-nav .title { font-family: var(--font-display); font-size: 1.2rem; color: var(--ink); }
.page-nav a:hover .title { color: var(--accent); }
.page-nav .next { text-align: right; grid-column: 2; }

/* ---------- Landing ---------- */
.page { max-width: var(--page); margin: 0 auto; padding-inline: var(--space-5); }
.hero { display: grid; grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr); gap: var(--space-7); align-items: center; padding-block: var(--space-8) var(--space-7); }
.hero h1 { margin-bottom: var(--space-5); }
.release { font-family: var(--font-mono); font-size: 0.8rem; color: var(--muted); text-decoration: none; border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 0.25rem 0.6rem; display: inline-block; margin-bottom: var(--space-5); }
.release:hover { color: var(--accent); border-color: var(--accent); }
.installer-command {
  display: flex; align-items: center; gap: var(--space-3);
  background: var(--code-paper); color: var(--code-ink);
  border: 1px solid var(--code-line); border-radius: var(--radius);
  padding: 0.55rem 0.55rem 0.55rem 1rem; margin-top: var(--space-3); max-width: 34rem;
}
.installer-command code { flex: 1; min-width: 0; font-size: 0.92rem; overflow-x: auto; white-space: nowrap; background: none; border: 0; padding: 0; color: inherit; }
.installer-command .p { color: #736a5f; margin-inline-end: 0.6em; user-select: none; }

.hero-visual { position: relative; aspect-ratio: 1; max-width: 480px; justify-self: center; width: 100%; }
.hero-visual svg { width: 100%; height: 100%; overflow: visible; }
.tier-label { font-family: var(--font-mono); font-size: 9px; letter-spacing: 0.08em; fill: var(--muted); text-transform: uppercase; }
.tier-band { fill: none; stroke: var(--accent); stroke-width: 62.5; }
.orbit { fill: none; stroke: var(--line-control); stroke-width: 0.75; stroke-dasharray: 2 5; }
.blob { fill: var(--secondary); }
.page-blob { fill: var(--ink); }
@media (prefers-reduced-motion: no-preference) {
  .page-blob { animation: page-tier 9s var(--ease) 1s infinite; }
  .orbit { animation: orbit-spin 90s linear infinite; transform-origin: 200px 200px; }
  @keyframes page-tier {
    0%, 8% { transform: translate(0, 0) scale(0.4); opacity: 0; }
    14% { transform: translate(0, 0) scale(1); opacity: 1; }
    30%, 42% { transform: translate(0, -150px); }
    58%, 70% { transform: translate(-150px, 0); }
    86%, 94% { transform: translate(0, 150px); opacity: 1; }
    100% { transform: translate(0, 150px); opacity: 0; }
  }
  @keyframes orbit-spin { to { transform: rotate(360deg); } }
}
.page-blob { transform-box: fill-box; transform-origin: center; }

.chapters { border-top: 1px solid var(--line); }
.chapter-row {
  display: grid; grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr); gap: var(--space-8);
  padding-block: var(--space-8); border-bottom: 1px solid var(--line); align-items: start;
}
.chapter-row h2 { margin-bottom: var(--space-4); }
.hero > *, .chapter-row > * { min-width: 0; }
.chapter-row .section-heading p { color: var(--ink-soft); max-width: 58ch; }
.chapter-row .code { margin-top: 0; }

dl.notes { margin: 0; display: grid; gap: 0; border-top: 1px solid var(--line); }
dl.notes > div { display: grid; grid-template-columns: 9rem 1fr; gap: var(--space-4); padding: var(--space-4) 0; border-bottom: 1px solid var(--line); }
dl.notes dt { font-family: var(--font-mono); font-size: 0.78rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--secondary); padding-top: 0.2rem; }
dl.notes dd { margin: 0; color: var(--ink-soft); }

.tier-stack { display: grid; gap: 6px; margin: 0; padding: 0; list-style: none; }
.tier-stack li {
  display: grid; grid-template-columns: 6.5rem 1fr auto; gap: var(--space-4); align-items: center;
  border: 1px solid var(--line); border-inline-start: 3px solid var(--accent); border-radius: var(--radius);
  padding: 0.7rem 1rem; margin: 0; background: var(--paper-raised);
}
.tier-stack li:nth-child(2) { border-inline-start-color: color-mix(in srgb, var(--accent) 78%, var(--paper)); }
.tier-stack li:nth-child(3) { border-inline-start-color: color-mix(in srgb, var(--accent) 56%, var(--paper)); }
.tier-stack li:nth-child(4) { border-inline-start-color: color-mix(in srgb, var(--accent) 38%, var(--paper)); }
.tier-stack li:nth-child(5) { border-inline-start-color: var(--secondary); }
.tier-stack .tier-name { font-family: var(--font-mono); font-size: 0.82rem; color: var(--ink); }
.tier-stack .tier-desc { color: var(--ink-soft); font-size: 0.92rem; }
.tier-stack .tier-type { font-family: var(--font-mono); font-size: 0.75rem; color: var(--muted); }

.ecosystem { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 0; border-top: 1px solid var(--line); }
.ecosystem a { padding: var(--space-5) var(--space-5) var(--space-5) 0; text-decoration: none; color: var(--ink); border-bottom: 1px solid var(--line); display: grid; grid-template-columns: 48px 1fr; gap: var(--space-4); align-items: start; }
.ecosystem a + a { padding-inline-start: var(--space-5); border-inline-start: 1px solid var(--line); }
.ecosystem img { width: 48px; height: 48px; object-fit: contain; }
.ecosystem h3 { font-size: 1.3rem; margin-bottom: var(--space-1); }
.ecosystem a:hover h3 { color: var(--accent); }
.ecosystem p { color: var(--ink-soft); font-size: 0.93rem; margin: 0; }

.ecosystem.stacked { grid-template-columns: minmax(0, 1fr); }
.ecosystem.stacked a + a { padding-inline-start: 0; border-inline-start: 0; }
.card-list.single { grid-template-columns: minmax(0, 1fr); margin-top: 0; }
.eco-section { padding-top: var(--space-8); }
.eco-section h2 { margin-bottom: var(--space-5); }

.faq details { border-bottom: 1px solid var(--line); padding: var(--space-4) 0; }
.faq summary { cursor: pointer; font-weight: 500; list-style: none; display: flex; justify-content: space-between; gap: var(--space-4); }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--accent); font-family: var(--font-mono); }
.faq details[open] summary::after { content: "−"; }
.faq details p { margin: var(--space-3) 0 0; color: var(--ink-soft); }

.finale { text-align: center; padding-block: var(--space-9) var(--space-6); }
.finale img { width: 88px; margin-bottom: var(--space-5); }
.finale .actions { justify-content: center; }

.reveal { opacity: 1; }
@media (prefers-reduced-motion: no-preference) {
  .js .reveal { opacity: 0; transform: translateY(16px); transition: opacity var(--motion-enter) var(--ease), transform var(--motion-enter) var(--ease); }
  .js .reveal.in { opacity: 1; transform: none; }
}

/* ---------- Responsive ---------- */
@media (max-width: 1180px) {
  .guide { grid-template-columns: 200px minmax(0, 1fr); }
  .page-toc { display: none; }
}
@media (max-width: 900px) {
  .hero, .chapter-row { grid-template-columns: minmax(0, 1fr); gap: var(--space-6); }
  .hero { padding-block: var(--space-7) var(--space-6); }
  .hero-visual { max-width: 340px; order: -1; }
  .chapter-row { padding-block: var(--space-7); }
  .guide { grid-template-columns: minmax(0, 1fr); gap: var(--space-5); padding-top: var(--space-5); }
  .side-nav { position: static; max-height: none; border: 1px solid var(--line); border-radius: var(--radius); padding: 0; }
  .side-nav details summary { display: flex; justify-content: space-between; cursor: pointer; padding: 0.75rem 1rem; font-family: var(--font-mono); font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--muted); list-style: none; min-height: 44px; align-items: center; }
  .side-nav details summary::after { content: "+"; color: var(--accent); }
  .side-nav details[open] summary::after { content: "−"; }
  .side-nav details > div { padding: 0 1rem 1rem; }
  .footer-inner { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
  .ecosystem { grid-template-columns: minmax(0, 1fr); }
  .ecosystem a + a { padding-inline-start: 0; border-inline-start: 0; }
}
@media (max-width: 720px) {
  .menu-toggle { display: inline-grid; }
  .primary-nav {
    display: none; position: absolute; top: var(--header-h); left: 0; right: 0;
    flex-direction: column; background: var(--paper); border-bottom: 1px solid var(--line);
    padding: var(--space-3) var(--space-4) var(--space-4);
  }
  .primary-nav.open { display: flex; }
  .primary-nav a { padding: 0.75rem 0.5rem; min-height: 44px; }
  .primary-nav a[aria-current="page"] { box-shadow: inset 2px 0 0 var(--accent); padding-inline-start: 0.9rem; }
  .header-inner { padding: 0 var(--space-4); gap: var(--space-3); }
  .header-tools { margin-inline-start: auto; }
  .page, .guide { padding-inline: var(--space-4); }
  dl.notes > div { grid-template-columns: minmax(0, 1fr); gap: var(--space-1); }
  .tier-stack li { grid-template-columns: minmax(0, 1fr); gap: var(--space-1); }
  .page-nav { grid-template-columns: minmax(0, 1fr); }
  .page-nav .next { grid-column: 1; text-align: left; }
  .footer-inner { grid-template-columns: minmax(0, 1fr); padding-inline: var(--space-4); }
  .footer-legal { padding-inline: var(--space-4); }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition-duration: 0ms !important; animation: none !important; }
}
.panel-meta { font-size: 0.9rem; color: var(--muted); }
.panel-meta strong { color: var(--ink); font-weight: 600; }
[id], .tabs { scroll-margin-top: 5rem; }