:root {
  color-scheme: light;
  --canvas: #f1f0ea;
  --canvas-deep: #e3e1d8;
  --paper: #fbfaf6;
  --ink: #0b2640;
  --ink-soft: #365166;
  --line: #b9c1c4;
  --line-strong: #7e919c;
  --signal: #007a6b;
  --signal-bright: #5de0c0;
  --copper: #a94121;
  --amber: #efb33e;
  --danger: #a62b2b;
  --white: #ffffff;
  --shadow: 0 22px 70px rgb(11 38 64 / 12%);
  --display: "Bahnschrift Condensed", "Arial Narrow", "Segoe UI", sans-serif;
  --body: "Segoe UI Variable", "Segoe UI", system-ui, -apple-system, sans-serif;
  --mono: "Cascadia Mono", Consolas, ui-monospace, monospace;
  --measure: 1180px;
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --canvas: #071725;
  --canvas-deep: #0c2133;
  --paper: #102a3e;
  --ink: #edf6f7;
  --ink-soft: #b8cad2;
  --line: #365468;
  --line-strong: #638094;
  --signal: #5de0c0;
  --signal-bright: #73e8cd;
  --copper: #ff9a78;
  --amber: #f3c96e;
  --danger: #ff8e8e;
  --white: #ffffff;
  --shadow: 0 24px 80px rgb(0 0 0 / 35%);
}

* {
  box-sizing: border-box;
}

html {
  overflow-x: hidden;
  overflow-x: clip;
  scroll-behavior: smooth;
  scroll-padding-top: 76px;
}

body {
  margin: 0;
  overflow-x: clip;
  background: var(--canvas);
  color: var(--ink);
  font: 16px/1.62 var(--body);
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body::before {
  position: fixed;
  z-index: -2;
  inset: 0;
  background-image:
    linear-gradient(rgb(11 38 64 / 4%) 1px, transparent 1px),
    linear-gradient(90deg, rgb(11 38 64 / 4%) 1px, transparent 1px);
  background-size: 40px 40px;
  content: "";
  pointer-events: none;
}

body::after {
  position: fixed;
  z-index: -1;
  width: 56vw;
  height: 56vw;
  top: -34vw;
  right: -12vw;
  border: 1px solid rgb(0 122 107 / 20%);
  border-radius: 50%;
  box-shadow: 0 0 0 12vw rgb(0 122 107 / 3%), 0 0 0 24vw rgb(0 122 107 / 2%);
  content: "";
  pointer-events: none;
}

::selection {
  background: var(--signal-bright);
  color: #061d2e;
}

a {
  color: inherit;
  text-underline-offset: .2em;
}

a:hover {
  text-decoration-thickness: 2px;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

:is(a, button):focus-visible {
  outline: 3px solid var(--amber);
  outline-offset: 4px;
}

h1,
h2,
h3,
p,
blockquote,
figure,
dl,
dd {
  margin: 0;
}

h1,
h2,
h3 {
  font-family: var(--display);
  font-weight: 700;
  line-height: .98;
  letter-spacing: -.025em;
  text-wrap: balance;
}

p,
li,
dd,
small {
  text-wrap: pretty;
}

.skip-link {
  position: fixed;
  z-index: 1000;
  left: 1rem;
  top: -8rem;
  padding: .8rem 1rem;
  border-radius: 0 0 .5rem .5rem;
  background: var(--amber);
  color: #0b2640;
  font-weight: 800;
}

.skip-link:focus {
  top: 0;
}

.site-header {
  position: sticky;
  z-index: 100;
  top: 0;
  min-height: 70px;
  display: flex;
  align-items: center;
  gap: 1.5rem;
  padding: .7rem max(1rem, calc((100vw - var(--measure)) / 2));
  border-bottom: 1px solid rgb(126 145 156 / 50%);
  background: rgb(241 240 234 / 88%);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
}

:root[data-theme="dark"] .site-header {
  background: rgb(7 23 37 / 88%);
}

.brand-back {
  display: inline-flex;
  align-items: center;
  gap: .7rem;
  margin-right: auto;
  color: var(--ink);
  text-decoration: none;
}

.brand-back > span:last-child {
  display: grid;
}

.brand-back strong {
  font-family: var(--display);
  font-size: 1.02rem;
  letter-spacing: .01em;
  line-height: 1.1;
  text-transform: uppercase;
}

.brand-back small {
  color: var(--ink-soft);
  font-family: var(--mono);
  font-size: .65rem;
  letter-spacing: .02em;
}

.brand-mark {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border: 1px solid var(--ink);
  border-radius: 50%;
  color: var(--ink);
  font: 800 .72rem/1 var(--mono);
}

.header-nav {
  display: flex;
  gap: .25rem;
}

.header-nav a {
  padding: .5rem .7rem;
  color: var(--ink-soft);
  font-size: .82rem;
  font-weight: 700;
  text-decoration: none;
}

.header-nav a:hover {
  color: var(--signal);
}

.theme-toggle {
  width: 40px;
  height: 40px;
  display: grid;
  place-items: center;
  flex: none;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
  background: transparent;
  color: var(--ink);
  cursor: pointer;
  font-size: 1.2rem;
}

.reading-progress {
  position: fixed;
  z-index: 120;
  top: 69px;
  left: 0;
  width: 100%;
  height: 3px;
  border: 0;
  background: transparent;
  color: var(--signal);
  appearance: none;
  pointer-events: none;
}

.reading-progress::-webkit-progress-bar {
  background: transparent;
}

.reading-progress::-webkit-progress-value {
  height: 100%;
  background: linear-gradient(90deg, var(--copper), var(--amber), var(--signal));
}

.reading-progress::-moz-progress-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--copper), var(--amber), var(--signal));
}

.chapter-rail {
  position: fixed;
  z-index: 80;
  top: 50%;
  right: 1rem;
  display: grid;
  gap: .35rem;
  transform: translateY(-50%);
}

.chapter-rail a {
  width: 32px;
  height: 32px;
  display: grid;
  place-items: center;
  border: 1px solid transparent;
  border-radius: 50%;
  color: var(--ink-soft);
  font: 700 .58rem/1 var(--mono);
  text-decoration: none;
}

.chapter-rail a:hover,
.chapter-rail a[aria-current="true"] {
  border-color: var(--signal);
  background: var(--paper);
  color: var(--signal);
}

.chapter {
  position: relative;
  min-height: min(920px, 100svh);
  padding: clamp(5rem, 9vw, 8.5rem) max(2.5rem, calc((100vw - var(--measure)) / 2));
  border-bottom: 1px solid var(--line);
}

.chapter > * {
  position: relative;
  z-index: 1;
}

.chapter-number,
.eyebrow,
.panel-label,
.case-kicker,
.myth-index {
  font-family: var(--mono);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
}

.chapter-number {
  margin-bottom: clamp(2rem, 5vw, 4.5rem);
  color: var(--signal);
}

.split-heading {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(280px, .8fr);
  gap: clamp(2rem, 7vw, 7rem);
  align-items: end;
  margin-bottom: clamp(2.5rem, 6vw, 5rem);
}

.split-heading h2 {
  max-width: 14ch;
  font-size: clamp(2.8rem, 6vw, 6.8rem);
}

.split-heading > p {
  max-width: 44rem;
  color: var(--ink-soft);
  font-size: clamp(1rem, 1.7vw, 1.25rem);
}

.hero {
  min-height: calc(100svh - 70px);
  display: flex;
  flex-direction: column;
  justify-content: center;
  isolation: isolate;
}

.hero::before {
  position: absolute;
  z-index: 0;
  width: clamp(280px, 46vw, 720px);
  aspect-ratio: 1;
  right: -12vw;
  top: 5%;
  border: 1px solid var(--line);
  border-radius: 50%;
  background:
    radial-gradient(circle at center, transparent 0 23%, var(--line) 23.2% 23.4%, transparent 23.6% 45%, var(--line) 45.2% 45.4%, transparent 45.6%);
  opacity: .65;
  content: "";
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(300px, .6fr);
  gap: clamp(3rem, 8vw, 8rem);
  align-items: center;
}

.eyebrow {
  margin-bottom: 1.4rem;
  color: var(--copper);
}

.hero h1 {
  max-width: 12ch;
  font-size: clamp(4rem, 9vw, 10rem);
  letter-spacing: -.055em;
}

.hero h1 em,
.closing h2 em {
  color: var(--signal);
  font-style: normal;
}

.hero-lead {
  max-width: 57rem;
  margin-top: 2rem;
  color: var(--ink-soft);
  font-size: clamp(1.08rem, 1.8vw, 1.35rem);
}

.hero-lead strong {
  color: var(--ink);
}

.hero-actions,
.author-links {
  display: flex;
  flex-wrap: wrap;
  gap: .7rem;
  margin-top: 2rem;
}

.button {
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .5rem;
  padding: .75rem 1.1rem;
  border: 1px solid var(--ink);
  border-radius: .3rem;
  font-weight: 800;
  text-decoration: none;
}

.button--primary {
  background: var(--ink);
  color: var(--canvas);
}

.button--primary:hover {
  background: var(--signal);
  border-color: var(--signal);
  color: #fff;
}

.button--ghost:hover {
  background: var(--paper);
}

.manifesto-card {
  position: relative;
  padding: clamp(2rem, 4vw, 3.5rem);
  border: 1px solid var(--line-strong);
  background: var(--paper);
  box-shadow: var(--shadow);
  transform: rotate(1.5deg);
}

.quote-mark {
  display: block;
  height: 3rem;
  color: var(--copper);
  font: 700 5rem/.8 Georgia, serif;
}

.manifesto-card p {
  font-family: var(--display);
  font-size: clamp(1.9rem, 3.4vw, 2.2rem);
  font-weight: 700;
  line-height: 1.02;
}

.manifesto-card footer {
  margin-top: 2rem;
  color: var(--ink-soft);
  font: .72rem/1.5 var(--mono);
}

.hero-equation {
  display: flex;
  align-items: stretch;
  gap: .5rem;
  margin-top: clamp(3rem, 8vw, 7rem);
}

.hero-equation span,
.hero-equation b {
  display: grid;
  place-items: center;
  min-height: 58px;
}

.hero-equation span {
  flex: 1;
  padding: .8rem;
  border: 1px solid var(--line-strong);
  background: rgb(251 250 246 / 60%);
  font-family: var(--display);
  font-size: clamp(1rem, 2.1vw, 1.55rem);
  font-weight: 700;
  text-transform: uppercase;
}

:root[data-theme="dark"] .hero-equation span {
  background: rgb(16 42 62 / 70%);
}

.hero-equation b {
  flex: none;
  color: var(--copper);
  font: 700 1.4rem/1 var(--mono);
}

.hero-equation .result {
  border-color: var(--signal);
  background: var(--signal);
  color: #fff;
}

.chapter--ink {
  overflow: hidden;
  background: #0b2640;
  color: #f3f7f7;
}

.chapter--ink::before {
  position: absolute;
  z-index: 0;
  inset: 0;
  background:
    linear-gradient(120deg, transparent 0 60%, rgb(93 224 192 / 8%) 60% 60.5%, transparent 60.5%),
    radial-gradient(circle at 85% 10%, rgb(93 224 192 / 14%), transparent 28%);
  content: "";
}

.chapter--ink .chapter-number,
.chapter--ink .myth-index {
  color: var(--signal-bright);
}

.chapter--ink .split-heading > p,
.chapter--ink .myth-grid p {
  color: #c1d1d8;
}

.myth-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  border: 1px solid #496578;
  background: #496578;
}

.myth-grid article {
  min-height: 350px;
  padding: clamp(1.5rem, 3vw, 2.7rem);
  background: #0b2640;
}

.myth-grid h3 {
  margin: 3.5rem 0 1.3rem;
  font-size: clamp(1.8rem, 3vw, 3rem);
}

.hard-stop {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1.5rem;
  align-items: start;
  max-width: 970px;
  margin: clamp(3rem, 6vw, 6rem) auto 0;
  padding-top: 2rem;
  border-top: 1px solid #496578;
}

.hard-stop > span {
  width: 54px;
  height: 54px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--amber);
  color: #0b2640;
  font: 900 1.5rem/1 var(--mono);
}

.hard-stop p {
  font-size: clamp(1.15rem, 2.2vw, 1.65rem);
}

.triad-workbench {
  display: grid;
  grid-template-columns: minmax(230px, .6fr) minmax(0, 1.4fr);
  gap: clamp(2rem, 6vw, 6rem);
}

.triad-controls {
  display: grid;
  align-content: start;
  gap: .7rem;
}

.triad-button {
  display: grid;
  grid-template-columns: 38px 1fr;
  gap: .1rem .8rem;
  padding: 1.2rem;
  border: 1px solid var(--line);
  border-radius: 0;
  background: var(--paper);
  color: var(--ink);
  text-align: left;
  cursor: pointer;
}

.triad-button[aria-pressed="true"] {
  border-color: var(--signal);
  box-shadow: inset 5px 0 0 var(--signal);
}

.triad-button .triad-code {
  grid-row: 1 / span 2;
  color: var(--copper);
  font: 700 .7rem/1.5 var(--mono);
}

.triad-button strong {
  font: 700 1.5rem/1 var(--display);
  text-transform: uppercase;
}

.triad-button small {
  color: var(--ink-soft);
  font-size: .76rem;
}

.triad-panels {
  position: relative;
}

.triad-panel {
  min-height: 535px;
  padding: clamp(2rem, 5vw, 4.5rem);
  border-top: 7px solid var(--signal);
  background: var(--paper);
  box-shadow: var(--shadow);
}

.js-ready .triad-panel[hidden] {
  display: none;
}

.panel-label {
  margin-bottom: 1rem;
  color: var(--signal);
}

.triad-panel h3 {
  max-width: 14ch;
  font-size: clamp(2rem, 4vw, 4.1rem);
}

.check-list {
  display: grid;
  gap: .8rem;
  margin: 2rem 0 0;
  padding: 0;
  list-style: none;
}

.check-list li {
  position: relative;
  padding-left: 1.8rem;
}

.check-list li::before {
  position: absolute;
  left: 0;
  top: .25rem;
  color: var(--signal);
  content: "↳";
  font-family: var(--mono);
}

.absence {
  margin-top: 2rem;
  padding: 1.1rem;
  border-left: 4px solid var(--copper);
  background: var(--canvas);
  color: var(--ink-soft);
}

.core-statement {
  max-width: 980px;
  margin: clamp(4rem, 8vw, 8rem) auto 0;
  font-family: var(--display);
  font-size: clamp(2rem, 4.4vw, 4.8rem);
  line-height: 1.03;
  text-align: center;
}

.core-statement strong {
  color: var(--signal);
}

.chapter--blueprint {
  background-color: #09243a;
  background-image:
    linear-gradient(rgb(93 224 192 / 9%) 1px, transparent 1px),
    linear-gradient(90deg, rgb(93 224 192 / 9%) 1px, transparent 1px),
    linear-gradient(rgb(93 224 192 / 4%) 1px, transparent 1px),
    linear-gradient(90deg, rgb(93 224 192 / 4%) 1px, transparent 1px);
  background-position: -1px -1px;
  background-size: 80px 80px, 80px 80px, 16px 16px, 16px 16px;
  color: #eff9fa;
}

.chapter--blueprint .chapter-number,
.chapter--blueprint .panel-label {
  color: var(--signal-bright);
}

.chapter--blueprint .split-heading > p {
  color: #b8ccd5;
}

.evidence-flow {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 0;
  margin: 0;
  padding: 0;
  list-style: none;
}

.evidence-flow li {
  position: relative;
  min-height: 170px;
  display: flex;
  flex-direction: column;
  padding: 1.2rem;
  border: 1px solid #46677b;
  background: rgb(9 36 58 / 84%);
}

.evidence-flow li + li {
  border-left: 0;
}

.evidence-flow li:not(:last-child)::after {
  position: absolute;
  z-index: 2;
  top: 50%;
  right: -11px;
  width: 20px;
  height: 20px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--signal-bright);
  color: #09243a;
  content: "›";
  font: 900 1rem/1 var(--mono);
  transform: translateY(-50%);
}

.evidence-flow span {
  margin-bottom: auto;
  color: var(--signal-bright);
  font: 700 .65rem/1 var(--mono);
}

.evidence-flow strong {
  font-family: var(--display);
  font-size: 1.25rem;
  text-transform: uppercase;
}

.evidence-flow small {
  margin-top: .45rem;
  color: #aec4ce;
  font-size: .73rem;
}

.evidence-matrix {
  margin-top: 4rem;
  border-top: 1px solid #557286;
}

.matrix-row {
  display: grid;
  grid-template-columns: minmax(140px, .55fr) minmax(240px, 1fr) minmax(240px, 1fr);
  gap: 2rem;
  padding: 1rem .5rem;
  border-bottom: 1px solid #3f5d70;
}

.matrix-row span {
  color: #c1d2d9;
}

.matrix-head {
  color: var(--signal-bright);
  font: 700 .65rem/1.4 var(--mono);
  letter-spacing: .1em;
  text-transform: uppercase;
}

.case-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.case-card {
  display: flex;
  flex-direction: column;
  min-height: 420px;
  padding: clamp(1.7rem, 4vw, 3.5rem);
  border: 1px solid var(--line-strong);
}

.case-card--bad {
  background: var(--canvas-deep);
}

.case-card--good {
  border-color: var(--signal);
  background: var(--paper);
}

.case-kicker {
  color: var(--copper);
}

.case-card--good .case-kicker {
  color: var(--signal);
}

.case-card h3 {
  margin: 2.5rem 0 1.5rem;
  font-size: clamp(2.4rem, 5vw, 5rem);
}

.case-card ul {
  display: grid;
  gap: .55rem;
  margin: 0;
  padding-left: 1.2rem;
  color: var(--ink-soft);
}

.verdict {
  margin-top: auto;
  padding-top: 2rem;
  color: var(--danger);
  font-family: var(--mono);
  font-size: .77rem;
  text-transform: uppercase;
}

.case-card--good .verdict {
  color: var(--signal);
}

.mortar-story {
  max-width: 1050px;
  margin: clamp(4rem, 9vw, 9rem) auto;
  padding: clamp(2rem, 5vw, 4.5rem);
  border-left: 8px solid var(--copper);
  background: var(--paper);
  box-shadow: var(--shadow);
}

.mortar-story p {
  font-family: var(--display);
  font-size: clamp(2rem, 4vw, 4.5rem);
  font-weight: 700;
  line-height: 1.03;
}

.mortar-story footer {
  margin-top: 2rem;
  color: var(--ink-soft);
}

.cpp-lane {
  display: grid;
  grid-template-columns: minmax(270px, .7fr) minmax(0, 1.3fr);
  gap: clamp(2rem, 7vw, 7rem);
  align-items: start;
}

.cpp-lane h3 {
  max-width: 12ch;
  font-size: clamp(2.3rem, 4.4vw, 4.8rem);
}

.cpp-lane > div:first-child > p:last-child {
  margin-top: 1.5rem;
  color: var(--ink-soft);
}

.code-stack {
  display: grid;
  gap: .75rem;
}

.code-stack figure {
  overflow: hidden;
  border: 1px solid var(--line-strong);
  background: #081e30;
  color: #e9f5f4;
}

.code-stack figcaption {
  padding: .7rem 1rem;
  border-bottom: 1px solid #37536a;
  color: #a9c2cf;
  font: .68rem/1.4 var(--mono);
  text-transform: uppercase;
}

pre {
  max-width: 100%;
  overflow: auto;
  margin: 0;
  padding: 1.1rem;
}

code {
  font-family: var(--mono);
}

pre code {
  color: var(--signal-bright);
  font-size: .82rem;
}

.technical-note,
.scope-note {
  max-width: 1050px;
  margin: 4rem auto 0;
  padding: 1.3rem 1.5rem;
  border: 1px solid var(--line-strong);
  background: var(--paper);
  color: var(--ink-soft);
}

.technical-note strong,
.scope-note strong {
  color: var(--ink);
}

.chapter--paper {
  background: var(--paper);
}

.document-stack {
  max-width: 980px;
  margin: 0 auto;
}

.document-stack article {
  position: relative;
  min-height: 160px;
  padding: 1.8rem 2rem;
  border: 1px solid var(--line-strong);
  background: var(--canvas);
  box-shadow: 0 12px 30px rgb(11 38 64 / 8%);
}

.document-stack article:nth-child(2) {
  width: 92%;
  margin: -1px auto 0;
}

.document-stack article:nth-child(3) {
  width: 84%;
  margin: -1px auto 0;
  border-color: var(--signal);
}

.document-stack span {
  color: var(--signal);
  font: 700 .68rem/1 var(--mono);
  letter-spacing: .1em;
}

.document-stack h3 {
  margin-top: .8rem;
  font-size: clamp(1.8rem, 3vw, 3rem);
}

.document-stack p {
  max-width: 60rem;
  margin-top: .6rem;
  color: var(--ink-soft);
}

.rule-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  margin: 4rem 0;
  border: 1px solid var(--line);
  background: var(--line);
}

.rule-grid article {
  min-height: 210px;
  padding: 1.5rem;
  background: var(--paper);
}

.rule-grid strong {
  font-family: var(--display);
  font-size: 1.4rem;
  text-transform: uppercase;
}

.rule-grid p {
  margin-top: 1rem;
  color: var(--ink-soft);
  font-size: .9rem;
}

.question-title {
  margin-top: 6rem;
  font-size: 1rem;
  letter-spacing: .1em;
  text-align: center;
  text-transform: uppercase;
}

.question-swap {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 1rem;
  align-items: stretch;
  margin-top: 1.5rem;
}

.question-swap p {
  min-height: 170px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 1.8rem;
  border: 1px solid var(--line-strong);
  font-family: var(--display);
  font-size: clamp(1.7rem, 3vw, 3rem);
  font-weight: 700;
  line-height: 1.04;
}

.question-swap p:last-child {
  border-color: var(--signal);
  background: var(--signal);
  color: #fff;
}

.question-swap span {
  margin-bottom: 1rem;
  font: 700 .65rem/1 var(--mono);
  letter-spacing: .1em;
}

.question-swap b {
  display: grid;
  place-items: center;
  color: var(--copper);
  font: 900 2rem/1 var(--mono);
}

.acceptance,
.ai-box {
  display: grid;
  grid-template-columns: minmax(250px, .7fr) minmax(0, 1.3fr);
  gap: clamp(2rem, 6vw, 6rem);
  margin-top: 6rem;
  padding-top: 3rem;
  border-top: 1px solid var(--line);
}

.acceptance h3,
.ai-box h3 {
  font-size: clamp(2.2rem, 4vw, 4rem);
}

.acceptance ol,
.ai-box ul {
  display: grid;
  gap: .8rem;
  margin: 0;
  padding-left: 1.4rem;
}

.acceptance li,
.ai-box li {
  padding-left: .5rem;
}

.ai-box {
  grid-template-columns: 1fr;
  gap: 1rem;
  padding: clamp(2rem, 5vw, 4rem);
  border: 1px solid var(--line-strong);
  background: var(--canvas);
}

.ai-box > p:not(.panel-label) {
  max-width: 72rem;
  color: var(--ink-soft);
  font-size: 1.05rem;
}

.chapter--standards {
  background: var(--canvas-deep);
}

.source-grid {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: .8rem;
}

.source-grid a {
  min-height: 270px;
  display: flex;
  flex-direction: column;
  padding: 1.4rem;
  border: 1px solid var(--line-strong);
  background: var(--paper);
  text-decoration: none;
}

.source-grid a:nth-child(1),
.source-grid a:nth-child(2) {
  grid-column: span 3;
}

.source-grid a:nth-child(n+3) {
  grid-column: span 2;
}

.source-grid a:hover {
  border-color: var(--signal);
  box-shadow: var(--shadow);
  transform: translateY(-3px);
}

.source-grid span {
  color: var(--signal);
  font: 700 .68rem/1 var(--mono);
  letter-spacing: .1em;
}

.source-grid strong {
  margin-top: auto;
  font-family: var(--display);
  font-size: clamp(1.6rem, 2.4vw, 2.6rem);
  line-height: 1.02;
}

.source-grid small {
  margin-top: .8rem;
  color: var(--ink-soft);
}

.launch-sequence {
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line-strong);
  list-style: none;
}

.launch-sequence li {
  display: grid;
  grid-template-columns: 90px 1fr;
  gap: 2rem;
  align-items: start;
  padding: 1.3rem 0;
  border-bottom: 1px solid var(--line);
}

.launch-sequence > li > span {
  color: var(--copper);
  font: 700 1.15rem/1.5 var(--mono);
}

.launch-sequence strong {
  font-family: var(--display);
  font-size: clamp(1.6rem, 3vw, 2.5rem);
  line-height: 1;
  text-transform: uppercase;
}

.launch-sequence p {
  margin-top: .4rem;
  color: var(--ink-soft);
}

.go-gate {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
  margin-top: 4rem;
}

.go-gate div {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1.3rem;
  padding: 1.7rem;
  border: 1px solid var(--line-strong);
  background: var(--paper);
}

.go-gate span {
  color: var(--signal);
  font: 900 1rem/1.5 var(--mono);
}

.go-gate div:last-child span {
  color: var(--danger);
}

.chapter--download {
  overflow: hidden;
  background: #0b2640;
  color: #f2f8f8;
}

.chapter--download::before {
  position: absolute;
  inset: -20% -10%;
  background: repeating-linear-gradient(-20deg, transparent 0 40px, rgb(93 224 192 / 4%) 40px 41px);
  content: "";
}

.chapter--download .chapter-number,
.chapter--download .panel-label {
  color: var(--signal-bright);
}

.chapter--download .split-heading > p {
  color: #bfd0d7;
}

.download-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.download-card {
  position: relative;
  min-height: 510px;
  display: flex;
  flex-direction: column;
  padding: clamp(2rem, 4vw, 3.5rem);
  border: 1px solid #527083;
  background: #102e45;
}

.download-card--md {
  border-color: var(--signal-bright);
}

.file-type {
  position: absolute;
  top: 1.5rem;
  right: 1.5rem;
  width: 64px;
  height: 64px;
  display: grid;
  place-items: center;
  border: 1px solid #7690a0;
  color: var(--signal-bright);
  font: 800 .85rem/1 var(--mono);
}

.download-card h3 {
  max-width: 12ch;
  margin-top: 2rem;
  font-size: clamp(2.5rem, 4.8vw, 5rem);
}

.download-card > p:not(.panel-label) {
  max-width: 35rem;
  margin-top: 1.5rem;
  color: #bfd0d7;
}

.download-card dl {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: .4rem 1rem;
  margin: 2rem 0;
  color: #bfd0d7;
  font-size: .78rem;
}

.download-card dt {
  color: #89a3b0;
  font-family: var(--mono);
  text-transform: uppercase;
}

.download-card .button {
  width: fit-content;
  margin-top: auto;
}

.button--light {
  border-color: var(--signal-bright);
  background: var(--signal-bright);
  color: #071725;
}

.button--light:hover {
  border-color: var(--amber);
  background: var(--amber);
}

.checksum-link {
  margin-top: 1.4rem;
  color: #a9c0ca;
  font: .72rem/1.5 var(--mono);
}

.closing {
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.closing-kicker {
  max-width: 65rem;
  color: var(--copper);
  font: 700 .8rem/1.4 var(--mono);
  letter-spacing: .08em;
  text-transform: uppercase;
}

.closing > h2 {
  max-width: 15ch;
  margin-top: 1.5rem;
  font-size: clamp(3.3rem, 8vw, 9rem);
  letter-spacing: -.045em;
}

.closing > h2 + p {
  margin-top: 2rem;
  color: var(--ink-soft);
  font-size: clamp(1.1rem, 2vw, 1.5rem);
}

.author-card {
  display: grid;
  grid-template-columns: 100px 1fr;
  gap: 1.5rem;
  align-items: center;
  margin-top: clamp(4rem, 8vw, 7rem);
  padding-top: 2rem;
  border-top: 1px solid var(--line);
}

.author-monogram {
  width: 90px;
  height: 90px;
  display: grid;
  place-items: center;
  border: 1px solid var(--ink);
  border-radius: 50%;
  font: 800 1.2rem/1 var(--mono);
}

.author-card h3 {
  font-size: clamp(1.8rem, 3vw, 3rem);
}

.author-card h3 + p {
  margin-top: .4rem;
  color: var(--ink-soft);
}

.author-links {
  margin-top: 1rem;
}

.author-links a {
  color: var(--signal);
  font-weight: 700;
}

.related {
  display: flex;
  flex-wrap: wrap;
  gap: .55rem;
  margin-top: 3rem;
  color: var(--ink-soft);
  font-size: .82rem;
}

.related span,
.related a {
  padding: .55rem .7rem;
  border: 1px solid var(--line);
  text-decoration: none;
}

.related span {
  border-color: transparent;
  padding-left: 0;
}

.related a:hover {
  border-color: var(--signal);
  color: var(--signal);
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.5rem max(2.5rem, calc((100vw - var(--measure)) / 2));
  border-top: 1px solid #3b586b;
  background: #071725;
  color: #abc0ca;
  font-size: .76rem;
}

@media (hover: hover) and (prefers-reduced-motion: no-preference) {
  .button,
  .source-grid a,
  .triad-button,
  .chapter-rail a,
  .theme-toggle {
    transition: color .18s ease, background-color .18s ease, border-color .18s ease, transform .18s ease, box-shadow .18s ease;
  }
}

@media (max-width: 1080px) {
  .chapter-rail {
    display: none;
  }

  .hero-grid,
  .triad-workbench,
  .cpp-lane {
    grid-template-columns: 1fr;
  }

  .hero-grid {
    gap: 3rem;
  }

  .manifesto-card {
    max-width: 680px;
  }

  .triad-controls {
    grid-template-columns: repeat(3, 1fr);
  }

  .evidence-flow {
    grid-template-columns: repeat(3, 1fr);
  }

  .evidence-flow li:nth-child(4) {
    border-left: 1px solid #46677b;
  }

  .rule-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 760px) {
  .site-header {
    gap: .6rem;
  }

  .brand-back small,
  .header-nav {
    display: none;
  }

  .chapter {
    min-height: 0;
    padding: 4.5rem 1.15rem;
  }

  .split-heading {
    grid-template-columns: 1fr;
    gap: 1.2rem;
  }

  .split-heading h2 {
    font-size: clamp(2.6rem, 13vw, 4.5rem);
  }

  .hero {
    min-height: calc(100svh - 70px);
  }

  .hero h1 {
    font-size: clamp(3.6rem, 17vw, 6rem);
  }

  .hero-equation {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
  }

  .hero-equation b:nth-of-type(2) {
    display: none;
  }

  .hero-equation .result {
    grid-column: 1 / -1;
  }

  .myth-grid,
  .case-grid,
  .download-grid,
  .go-gate {
    grid-template-columns: 1fr;
  }

  .myth-grid article {
    min-height: 280px;
  }

  .triad-controls {
    grid-template-columns: 1fr;
  }

  .triad-panel {
    min-height: 0;
    padding: 1.5rem;
  }

  .evidence-flow {
    grid-template-columns: 1fr;
  }

  .evidence-flow li,
  .evidence-flow li + li,
  .evidence-flow li:nth-child(4) {
    min-height: 130px;
    border: 1px solid #46677b;
    border-top: 0;
  }

  .evidence-flow li:first-child {
    border-top: 1px solid #46677b;
  }

  .evidence-flow li:not(:last-child)::after {
    top: auto;
    right: 1rem;
    bottom: -11px;
    transform: rotate(90deg);
  }

  .matrix-row,
  .matrix-head {
    grid-template-columns: 1fr;
    gap: .3rem;
  }

  .matrix-head {
    display: none;
  }

  .document-stack article:nth-child(n) {
    width: 100%;
  }

  .rule-grid,
  .source-grid {
    grid-template-columns: 1fr;
  }

  .source-grid a:nth-child(n) {
    grid-column: auto;
    min-height: 240px;
  }

  .question-swap {
    grid-template-columns: 1fr;
  }

  .question-swap b {
    transform: rotate(90deg);
  }

  .acceptance {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .launch-sequence li {
    grid-template-columns: 52px 1fr;
    gap: 1rem;
  }

  .go-gate div {
    grid-template-columns: 1fr;
  }

  .download-card {
    min-height: 500px;
    padding: 1.5rem;
  }

  .download-card h3 {
    padding-right: 3rem;
  }

  .file-type {
    width: 48px;
    height: 48px;
    top: 1rem;
    right: 1rem;
  }

  .author-card {
    grid-template-columns: 1fr;
  }

  .site-footer {
    flex-direction: column;
    padding: 1.5rem 1.15rem;
  }
}

@media (max-width: 420px) {
  .brand-mark {
    width: 34px;
    height: 34px;
  }

  .hero-actions,
  .hero-actions .button,
  .download-card .button {
    width: 100%;
  }

  .hero-equation {
    grid-template-columns: 1fr;
  }

  .hero-equation b {
    min-height: 24px;
  }

  .hero-equation b:nth-of-type(2) {
    display: grid;
  }

  .hero-equation .result {
    grid-column: auto;
  }

  .hard-stop {
    grid-template-columns: 1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: .01ms !important;
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
  }
}

@media print {
  :root {
    --canvas: #fff;
    --paper: #fff;
    --ink: #000;
    --ink-soft: #222;
  }

  .site-header,
  .chapter-rail,
  .reading-progress,
  .hero-actions,
  .theme-toggle {
    display: none !important;
  }

  .chapter {
    min-height: 0;
    break-inside: avoid;
    padding: 2rem 0;
  }

  .chapter--ink,
  .chapter--blueprint,
  .chapter--download {
    background: #fff;
    color: #000;
  }

  .triad-panel[hidden] {
    display: block !important;
  }
}