/* Shared styles for the learning pages (/field-guide, /approach, /growth, /glossary).
   Tokens follow the home page's palette and type; dark values are derived from it. */

@font-face {
  font-family: 'JetBrains Mono';
  font-style: normal;
  font-weight: 400 600;
  font-display: swap;
  src: url('/fonts/jetbrains-mono-latin-ext.woff2') format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
@font-face {
  font-family: 'JetBrains Mono';
  font-style: normal;
  font-weight: 400 600;
  font-display: swap;
  src: url('/fonts/jetbrains-mono-latin.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

:root {
  --paper: #F5F3EC;
  --surface: #FFFFFF;
  --ink: #16161B;
  --body-ink: #4A4A52;
  --muted: #55555E;
  --rule: #DEDAD0;
  --accent: #3B2FE0;
  --accent-hover: #2A20B0;
  --accent-ink: #FFFFFF;
  --accent-soft: #E4E2F2;
  --c1: #3B2FE0;
  --c2: #B4580A;
  --c-neutral: #B9B7C8;
  --grid: #ECE9E0;
  --display: 'Space Grotesk', system-ui, sans-serif;
  --body: 'IBM Plex Sans', system-ui, sans-serif;
  --mono: 'JetBrains Mono', ui-monospace, Menlo, Consolas, monospace;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #121216; --surface: #1B1B21; --ink: #EDEBE4; --body-ink: #C4C3CC; --muted: #A2A2AE;
    --rule: #2E2E37; --accent: #9A93FF; --accent-hover: #B4AEFF; --accent-ink: #121216; --accent-soft: #25234A;
    --c1: #8178FF; --c2: #E0954A; --c-neutral: #5A5A66; --grid: #26262E;
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --paper: #121216; --surface: #1B1B21; --ink: #EDEBE4; --body-ink: #C4C3CC; --muted: #A2A2AE;
  --rule: #2E2E37; --accent: #9A93FF; --accent-hover: #B4AEFF; --accent-ink: #121216; --accent-soft: #25234A;
  --c1: #8178FF; --c2: #E0954A; --c-neutral: #5A5A66; --grid: #26262E;
  color-scheme: dark;
}

*, *::before, *::after { box-sizing: border-box; }
html { background: var(--paper); }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--body);
  font-size: 1.0625rem;
  line-height: 1.62;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
a { color: var(--accent); text-underline-offset: 3px; }
a:hover { color: var(--accent-hover); }
a:focus-visible, button:focus-visible, input:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }
img, svg { max-width: 100%; }

.wrap {
  max-width: 1248px;
  margin: 0 auto;
  padding-left: max(16px, min(4vw, 48px), env(safe-area-inset-left, 0px));
  padding-right: max(16px, min(4vw, 48px), env(safe-area-inset-right, 0px));
}

/* Header */
.site { border-bottom: 1px solid var(--rule); background: var(--paper); }
.bar { display: flex; align-items: center; gap: 12px 32px; padding-block: 20px; flex-wrap: wrap; }
.brand { font-family: var(--display); font-weight: 700; font-size: 1.6rem; letter-spacing: -0.5px; color: var(--ink); text-decoration: none; }
.brand:hover { color: var(--ink); }
.bar nav { display: flex; gap: 8px 24px; flex-wrap: wrap; flex: 1; }
.bar nav a { color: var(--ink); text-decoration: none; font-size: 1rem; }
.bar nav a:hover { color: var(--accent); }
.bar nav a[aria-current="page"] { box-shadow: inset 0 -2px 0 var(--accent); }
.bar .end { display: flex; gap: 20px; align-items: center; }
.bar .end > a:not(.btn) { color: var(--ink); text-decoration: none; }
.btn {
  display: inline-block; font-family: var(--body); font-weight: 600; font-size: 1rem;
  background: var(--accent); color: var(--accent-ink); text-decoration: none;
  padding: 12px 22px; border-radius: 999px; border: 0; cursor: pointer;
}
.btn:hover { background: var(--accent-hover); color: var(--accent-ink); }
.btn.ghost { background: transparent; color: var(--ink); box-shadow: inset 0 0 0 1.5px var(--ink); }
.btn.ghost:hover { background: var(--accent-soft); color: var(--ink); }

/* Type */
.eyebrow { font-family: var(--body); font-size: 0.8125rem; font-weight: 600; letter-spacing: 1.5px; text-transform: uppercase; color: var(--accent); }
h1, h2, h3 { font-family: var(--display); letter-spacing: -0.025em; line-height: 1.05; text-wrap: balance; margin: 0; }
h1 { font-size: clamp(2.375rem, 6vw, 4.75rem); font-weight: 700; letter-spacing: -0.03em; line-height: 0.98; }
h2 { font-size: clamp(1.75rem, 3.4vw, 2.5rem); font-weight: 700; }
h3 { font-size: 1.25rem; font-weight: 600; letter-spacing: -0.01em; line-height: 1.2; }
.dek { font-size: clamp(1.15rem, 2vw, 1.3125rem); line-height: 1.5; color: var(--body-ink); max-width: 46ch; margin: 0; }
p { margin: 0; }
.prose { display: grid; gap: 1.1em; max-width: 68ch; }
.prose ul { margin: 0; padding-left: 1.2em; display: grid; gap: 0.4em; }
strong { font-weight: 600; }

/* Hero */
.hero { padding-block: clamp(40px, 7vw, 96px) clamp(28px, 5vw, 56px); display: grid; gap: 24px; }
.byline { font-family: var(--mono); font-size: 0.8rem; color: var(--muted); display: flex; gap: 16px; flex-wrap: wrap; }

/* Article with layer rail */
.article { display: grid; grid-template-columns: 210px minmax(0, 1fr); gap: 56px; padding-block: 16px 72px; }
.rail { position: sticky; top: 24px; align-self: start; display: grid; gap: 2px; font-size: 0.9375rem; }
.rail span { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.12em; text-transform: uppercase; color: var(--muted); margin-bottom: 8px; }
.rail a { color: var(--muted); text-decoration: none; padding: 6px 0 6px 12px; border-left: 2px solid var(--rule); }
.rail a:hover { color: var(--ink); border-left-color: var(--accent); }
.body { min-width: 0; display: grid; gap: 64px; }
.section { display: grid; gap: 18px; scroll-margin-top: 24px; min-width: 0; }
.layer-tag { font-family: var(--mono); font-size: 0.78rem; color: var(--accent); letter-spacing: 0.04em; }

.sowhat {
  background: var(--accent-soft); border-radius: 12px; padding: 18px 20px; max-width: 68ch;
  display: grid; gap: 6px; font-size: 1rem;
}
.sowhat b { font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--accent); font-weight: 600; }

.figure { margin: 0; display: grid; gap: 10px; min-width: 0; }
.figure .scroll { overflow-x: auto; background: var(--surface); border: 1px solid var(--rule); border-radius: 12px; padding: 20px; }
.figure figcaption { font-family: var(--mono); font-size: 0.78rem; color: var(--muted); }
.figure figcaption a { color: var(--muted); }
.figure .head { display: grid; gap: 4px; }
.figure .ctitle { font-family: var(--display); font-weight: 600; font-size: 1.15rem; letter-spacing: -0.01em; }
.figure .csub { font-size: 0.95rem; color: var(--muted); }

/* Diagrams: inline SVG coloured from tokens */
.diagram svg { display: block; min-width: 480px; width: 100%; max-width: 760px; height: auto; }
.diagram text { font-family: var(--display); fill: var(--ink); }
.diagram .mono { font-family: var(--mono); }
.diagram .muted { fill: var(--muted); }
.diagram .accent { fill: var(--accent); }
.diagram .box { fill: var(--surface); stroke: var(--rule); }
.diagram .box-on { fill: var(--accent-soft); stroke: var(--accent); }
.diagram .line { fill: none; stroke: var(--muted); }
.diagram .line-on { fill: none; stroke: var(--accent); }
.diagram .head-fill { fill: var(--muted); }

/* Charts */
.legend { display: flex; gap: 18px; flex-wrap: wrap; font-family: var(--mono); font-size: 0.74rem; color: var(--muted); }
.legend i { display: inline-block; width: 10px; height: 10px; border-radius: 2px; margin-right: 6px; vertical-align: -1px; }
.legend i.dash { background: transparent; border: 1.5px dashed var(--c1); width: 8px; height: 8px; }
.figure .chart { overflow: hidden; }
.chart svg { display: block; max-width: 100%; height: auto; }
.chart text { font-family: var(--mono); }
.chart .lbl { font-family: var(--display); }
.chart [tabindex]:focus-visible { outline: 2px solid var(--accent); }
.chart-tip { position: fixed; z-index: 30; pointer-events: none; background: var(--ink); color: var(--paper); font-family: var(--mono); font-size: 0.78rem; line-height: 1.4; padding: 7px 10px; border-radius: 6px; max-width: 260px; }

.pull { font-family: var(--display); font-weight: 600; font-size: clamp(1.4rem, 2.8vw, 1.9rem); line-height: 1.25; letter-spacing: -0.02em; max-width: 30ch; border-top: 2px solid var(--ink); padding-top: 18px; }

table.compare { border-collapse: collapse; width: 100%; font-size: 0.98rem; }
.tablewrap { overflow-x: auto; max-width: 100%; }
table.compare th, table.compare td { text-align: left; padding: 10px 14px 10px 0; border-bottom: 1px solid var(--rule); vertical-align: top; }
table.compare th { font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); font-weight: 500; }
table.compare td:first-child { font-family: var(--display); font-weight: 600; }

/* Stat strip */
.stats { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border-top: 2px solid var(--ink); border-bottom: 1px solid var(--rule); }
.stat { padding: 18px 18px 20px 0; display: grid; gap: 8px; align-content: start; }
.stat + .stat { padding-left: 18px; border-left: 1px solid var(--rule); }
.stat .num { font-family: var(--display); font-weight: 700; font-size: clamp(2rem, 4vw, 2.75rem); letter-spacing: -0.03em; line-height: 1; font-variant-numeric: tabular-nums; color: var(--accent); }
.stat p { font-size: 0.95rem; line-height: 1.4; }
.stat cite { font-family: var(--mono); font-size: 0.7rem; color: var(--muted); font-style: normal; }

.sources { display: grid; gap: 10px; max-width: 68ch; }
.sources ol { margin: 0; padding-left: 1.3em; display: grid; gap: 6px; font-size: 0.95rem; color: var(--muted); }

/* Bands and grids */
.band { background: var(--surface); border-block: 1px solid var(--rule); }
.band .inner { padding-block: clamp(40px, 6vw, 88px); display: grid; gap: 28px; }
.grid3 { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 28px; }
.cell { display: grid; gap: 10px; align-content: start; border-top: 1px solid var(--ink); padding-top: 16px; }
.cell p { color: var(--body-ink); font-size: 1rem; }
a.cell { text-decoration: none; color: inherit; }
a.cell:hover h3 { color: var(--accent); }

.steps { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 24px; counter-reset: s; }
.steps li { counter-increment: s; display: grid; gap: 8px; align-content: start; }
.steps li::before { content: counter(s); font-family: var(--display); font-weight: 700; font-size: 2.6rem; line-height: 1; color: var(--accent); }
.steps p { color: var(--body-ink); font-size: 1rem; }

.cta { display: grid; gap: 18px; padding-block: clamp(48px, 7vw, 96px); }
.cta .row { display: flex; gap: 12px; flex-wrap: wrap; align-items: center; }
.cta small { font-family: var(--mono); font-size: 0.8rem; color: var(--muted); }

/* Footer */
footer.site-foot { border-top: 1px solid var(--rule); }
footer.site-foot .wrap { padding-block: 40px; display: flex; gap: 20px 32px; flex-wrap: wrap; justify-content: space-between; align-items: flex-start; font-size: 0.9375rem; color: var(--muted); }
footer.site-foot .brand { font-size: 1.375rem; }
footer.site-foot nav { display: flex; gap: 10px 28px; flex-wrap: wrap; }
footer.site-foot a:not(.brand) { color: var(--muted); text-decoration: none; }
footer.site-foot a:not(.brand):hover { color: var(--ink); }
footer.site-foot small { width: 100%; font-family: var(--mono); font-size: 0.78rem; }

@media (max-width: 900px) {
  .article { grid-template-columns: minmax(0, 1fr); gap: 0; }
  .rail { display: none; }
  .grid3, .steps { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .stats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .stat:nth-child(3) { padding-left: 0; border-left: 0; }
  .stat:nth-child(n+3) { border-top: 1px solid var(--rule); }
}
@media (max-width: 560px) {
  .grid3, .steps, .stats { grid-template-columns: minmax(0, 1fr); }
  .stat, .stat + .stat { padding-left: 0; border-left: 0; }
  .stat + .stat { border-top: 1px solid var(--rule); }
  .bar { padding-block: 16px; }
  .bar nav { order: 3; flex-basis: 100%; gap: 6px 18px; }
  .bar .end { margin-left: auto; }
  .bar .end .btn { padding: 9px 16px; font-size: 0.9375rem; }
  body { font-size: 1rem; }
  .figure .scroll { padding: 14px; }
}
@media (prefers-reduced-motion: no-preference) {
  html { scroll-behavior: smooth; }
}

/* /approach: model routing table */
.route { display: grid; border: 1px solid var(--rule); border-radius: 12px; overflow: hidden; background: var(--paper); }
.route > div { display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr); gap: 16px; padding: 14px 18px; border-bottom: 1px solid var(--rule); font-size: 1rem; }
.route > div:last-child { border-bottom: 0; }
.route .head { font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); background: var(--surface); }
@media (max-width: 560px) { .route > div { grid-template-columns: minmax(0, 1fr); gap: 4px; } .route .head { display: none; } .route > div > span:last-child { color: var(--muted); } }

/* /growth: lead flow and modules */
.flow { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); border: 1px solid var(--rule); border-radius: 12px; overflow: hidden; background: var(--surface); }
.flow li { padding: 18px 16px; border-right: 1px solid var(--rule); display: grid; gap: 6px; align-content: start; }
.flow li:last-child { border-right: 0; background: var(--accent-soft); }
.flow .t { font-family: var(--mono); font-size: 0.72rem; color: var(--accent); letter-spacing: 0.06em; }
.flow h3 { font-size: 1.05rem; }
.flow p { font-size: 0.95rem; color: var(--body-ink); }
.mods { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); border-top: 1px solid var(--ink); }
.mod { display: grid; grid-template-columns: 44px minmax(0, 1fr); gap: 14px; padding: 22px 24px 22px 0; border-bottom: 1px solid var(--rule); }
.mod:nth-child(odd) { border-right: 1px solid var(--rule); }
.mod:nth-child(even) { padding-left: 24px; }
.mod svg { width: 36px; height: 36px; color: var(--accent); }
.mod p { color: var(--body-ink); font-size: 1rem; margin-top: 6px; }
.mod .who { font-family: var(--mono); font-size: 0.72rem; color: var(--accent); letter-spacing: 0.06em; text-transform: uppercase; margin-top: 8px; display: block; }
@media (max-width: 900px) { .flow { grid-template-columns: minmax(0, 1fr); } .flow li { border-right: 0; border-bottom: 1px solid var(--rule); } .flow li:last-child { border-bottom: 0; } }
@media (max-width: 700px) { .mods { grid-template-columns: minmax(0, 1fr); } .mod:nth-child(odd) { border-right: 0; } .mod:nth-child(even) { padding-left: 0; } }

/* /glossary: search, layer chips and term list */
.tools { display: grid; gap: 14px; padding-block: 8px 28px; }
.search { width: 100%; max-width: 520px; font: inherit; font-size: 1.05rem; padding: 12px 16px; border-radius: 10px; border: 1.5px solid var(--rule); background: var(--surface); color: var(--ink); }
.search::placeholder { color: var(--muted); }
.chips { display: flex; gap: 8px; flex-wrap: wrap; }
.chip { font-family: var(--body); font-size: 0.9rem; font-weight: 500; padding: 6px 14px; border-radius: 999px; border: 1.5px solid var(--rule); background: transparent; color: var(--muted); cursor: pointer; }
.chip:hover { color: var(--ink); border-color: var(--ink); }
.chip[aria-pressed="true"] { background: var(--ink); border-color: var(--ink); color: var(--paper); }
.count { font-family: var(--mono); font-size: 0.78rem; color: var(--muted); }
.terms { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); column-gap: 48px; padding-bottom: 72px; }
.term { display: grid; gap: 6px; padding-block: 18px; border-top: 1px solid var(--rule); align-content: start; scroll-margin-top: 24px; }
.term:target { background: var(--accent-soft); box-shadow: 0 0 0 12px var(--accent-soft); border-radius: 2px; }
.term .top { display: flex; gap: 12px; align-items: baseline; justify-content: space-between; flex-wrap: wrap; }
.term h3 { font-size: 1.2rem; }
.term .layer { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--accent); }
.term p { font-size: 1rem; }
.term .ex { color: var(--muted); font-style: italic; font-size: 0.97rem; }
.empty { padding-block: 24px 72px; color: var(--muted); }
@media (max-width: 760px) { .terms { grid-template-columns: minmax(0, 1fr); } }