@font-face {
  font-family: "Departure Mono";
  src: url("assets/fonts/DepartureMono-Regular.woff2") format("woff2");
  font-display: swap;
  font-style: normal;
  font-weight: 400;
}

:root {
  --paper: #f4f4ee;
  --paper-deep: #e9e9df;
  --ink: #a51c30;
  --ink-dark: #7a1622;
  --ink-55: rgba(165, 28, 48, 0.55);
  --ink-28: rgba(165, 28, 48, 0.28);
  --ink-12: rgba(165, 28, 48, 0.12);
  --ink-06: rgba(165, 28, 48, 0.06);
  --type: "Departure Mono", "Courier New", monospace;
  --header-height: 50px;
  --page-gutter: clamp(20px, 3.2vw, 54px);
  --book-width: 1160px;
  --text-width: 680px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  background: var(--paper);
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--type);
  font-size: 15px;
  line-height: 1.66;
  text-rendering: geometricPrecision;
}

body.menu-open {
  overflow: hidden;
}

a,
button {
  color: inherit;
}

a {
  text-decoration-thickness: 1px;
  text-underline-offset: 4px;
}

:focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 4px;
}

.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  padding: 8px 12px;
  color: var(--paper);
  background: var(--ink);
  font: 11px/1.2 var(--type);
  text-decoration: none;
  transform: translateY(-150%);
  transition: transform 160ms ease;
  z-index: 120;
}

.skip-link:focus {
  transform: translateY(0);
}

button {
  font: inherit;
}

::selection {
  color: var(--paper);
  background: var(--ink);
}

.page-progress {
  position: fixed;
  inset: 0 0 auto;
  height: 2px;
  z-index: 100;
  pointer-events: none;
}

.page-progress span {
  display: block;
  width: 100%;
  height: 100%;
  background: var(--ink);
  transform: scaleX(0);
  transform-origin: left;
}

.edge-ruler {
  display: none;
}

.site-header {
  position: sticky;
  top: 0;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  min-height: var(--header-height);
  padding: 0 var(--page-gutter);
  border-bottom: 1px solid var(--ink-28);
  background: rgba(244, 244, 238, 0.96);
  backdrop-filter: blur(12px);
  z-index: 50;
}

.brand,
.header-chapter,
.chapter-nav {
  font-size: 10px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  width: fit-content;
  text-decoration: none;
}

.brand span,
.header-chapter span {
  opacity: 0.56;
}

.brand strong,
.header-chapter strong {
  font-weight: 400;
}

.header-chapter {
  display: flex;
  gap: 8px;
}

.chapter-nav {
  display: flex;
  justify-content: flex-end;
  gap: 24px;
}

.chapter-nav a {
  text-decoration: none;
}

.chapter-nav a:hover,
.chapter-nav a:focus-visible {
  text-decoration: underline;
}

.menu-button {
  display: none;
  justify-self: end;
  padding: 0;
  border: 0;
  background: transparent;
  font-size: 10px;
  cursor: pointer;
}

.mobile-outline {
  position: fixed;
  inset: 0;
  display: none;
  padding: 24px;
  color: var(--paper);
  background: var(--ink);
  z-index: 80;
}

.mobile-outline.is-open {
  display: block;
}

.mobile-outline-head {
  display: flex;
  justify-content: space-between;
  padding-bottom: 16px;
  border-bottom: 1px solid rgba(244, 244, 238, 0.5);
  font-size: 10px;
}

.mobile-outline button {
  padding: 0;
  border: 0;
  color: inherit;
  background: transparent;
}

.mobile-outline ol {
  margin: 42px 0 0;
  padding: 0;
  list-style: none;
}

.mobile-outline li {
  border-bottom: 1px solid rgba(244, 244, 238, 0.3);
}

.mobile-outline a {
  display: block;
  padding: 13px 0;
  text-decoration: none;
}

main {
  overflow: clip;
}

.cover {
  display: grid;
  grid-template-columns: 160px minmax(0, var(--text-width)) 160px;
  column-gap: 38px;
  max-width: var(--book-width);
  margin: 0 auto;
  padding: clamp(62px, 9vw, 126px) var(--page-gutter) 88px;
  border-bottom: 1px solid var(--ink-28);
}

.cover-meta {
  grid-column: 1;
  grid-row: 1 / span 3;
  display: grid;
  align-content: start;
  gap: 18px;
  padding-top: 5px;
}

.cover-meta div {
  display: grid;
  gap: 1px;
}

.cover-meta span,
.cover-meta strong,
.cover-title > p:first-child,
.cover-footer,
.technical-figure figcaption,
.figure-controls,
.contents-heading > span,
.contents-stats span,
.chapter-outline,
.section-kicker,
.section-number,
.formula-note span,
.variable-machine span,
.variable-machine strong,
.comparison-diagram span,
.comparison-diagram small,
.code-plate,
.workflow-list span,
.schedule-list span,
.schedule-list small,
.closing-note > span,
.closing-note a,
.margin-register,
.site-footer {
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.cover-meta span,
.cover-meta strong {
  font-size: 10px;
  font-weight: 400;
}

.cover-meta span {
  opacity: 0.55;
}

.cover-title {
  grid-column: 2;
  padding-bottom: 34px;
}

.cover-title > p:first-child {
  margin: 0 0 30px;
  font-size: 10px;
}

.cover h1 {
  max-width: 10ch;
  margin: 0;
  font-size: clamp(58px, 6.3vw, 91px);
  font-weight: 400;
  letter-spacing: -0.07em;
  line-height: 0.96;
}

.cover-deck {
  max-width: 48ch;
  margin: 30px 0 0;
  color: var(--ink-dark);
  font-size: 17px;
  line-height: 1.55;
}

.cover-intro {
  grid-column: 2;
  display: block;
  max-width: 63ch;
  padding: 28px 0 62px;
  border-top: 1px solid var(--ink-28);
}

.cover-intro p {
  margin: 0 0 20px;
}

.cover-intro p:last-child {
  margin-bottom: 0;
}

.cover-intro .dropcap {
  color: var(--ink-dark);
  font-size: 17px;
  line-height: 1.62;
}

.dropcap::first-letter {
  float: left;
  margin: 7px 9px 0 0;
  font-size: 56px;
  line-height: 0.72;
}

.technical-figure {
  margin: 0;
}

.cover-figure {
  grid-column: 2 / 4;
  width: min(830px, 100%);
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}

.technical-figure figcaption {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  min-height: 34px;
  padding: 0 9px;
  border-bottom: 1px solid var(--ink-28);
  font-size: 9px;
}

.technical-figure figcaption span:nth-child(2) {
  text-align: center;
}

.technical-figure figcaption span:last-child {
  text-align: right;
}

.plot-frame {
  position: relative;
  height: clamp(350px, 45vw, 540px);
  background-image:
    linear-gradient(var(--ink-12) 1px, transparent 1px),
    linear-gradient(90deg, var(--ink-12) 1px, transparent 1px);
  background-size: 12.5% 16.666%;
}

#hero-plot,
#residual-plot {
  display: block;
  width: 100%;
  height: 100%;
}

.axis-label {
  position: absolute;
  font-size: 9px;
  pointer-events: none;
}

.axis-label-y {
  top: 50%;
  left: 10px;
  transform: rotate(-90deg) translateX(-50%);
  transform-origin: left top;
}

.axis-label-x {
  right: 10px;
  bottom: 7px;
}

.figure-controls {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 24px;
  align-items: center;
  min-height: 54px;
  padding: 9px;
  border-top: 1px solid var(--ink-28);
  font-size: 9px;
}

.figure-controls p {
  max-width: 66ch;
  margin: 0;
  text-transform: none;
}

.figure-controls button {
  padding: 5px 7px;
  border: 1px solid var(--ink);
  border-radius: 0;
  background: transparent;
  font-size: 9px;
  cursor: pointer;
}

.figure-controls button:hover,
.figure-controls button:focus-visible {
  color: var(--paper);
  background: var(--ink);
}

.cover-footer {
  grid-column: 2 / 4;
  display: flex;
  flex-wrap: wrap;
  gap: 12px 28px;
  padding-top: 18px;
  font-size: 9px;
  opacity: 0.68;
}

.contents-panel {
  display: grid;
  grid-template-columns: 160px minmax(0, var(--text-width)) 160px;
  column-gap: 38px;
  max-width: var(--book-width);
  margin: 0 auto;
  padding: 90px var(--page-gutter) 100px;
  border-bottom: 1px solid var(--ink-28);
  scroll-margin-top: calc(var(--header-height) + 20px);
}

.contents-heading {
  grid-column: 2;
}

.contents-heading > span {
  display: block;
  margin-bottom: 14px;
  font-size: 9px;
}

.contents-heading h2 {
  margin: 0 0 44px;
  font-size: clamp(42px, 4.2vw, 62px);
  font-weight: 400;
  letter-spacing: -0.06em;
  line-height: 1;
}

.contents-list {
  grid-column: 2;
  counter-reset: contents;
  display: grid;
  grid-template-columns: 1fr 1fr;
  column-gap: 46px;
}

.contents-list a {
  display: grid;
  grid-template-columns: 32px 1fr;
  gap: 0 10px;
  padding: 12px 0;
  border-top: 1px solid var(--ink-28);
  text-decoration: none;
}

.contents-list a:hover strong,
.contents-list a:focus-visible strong {
  text-decoration: underline;
  text-underline-offset: 4px;
}

.contents-list span,
.contents-list small {
  font-size: 9px;
}

.contents-list span {
  grid-row: 1 / span 2;
  opacity: 0.55;
}

.contents-list strong {
  font-size: 14px;
  font-weight: 400;
}

.contents-list small {
  margin-top: 2px;
  opacity: 0.62;
}

.contents-stats {
  grid-column: 3;
  grid-row: 1 / span 2;
  display: grid;
  align-content: start;
  gap: 16px;
  padding-top: 3px;
}

.contents-stats div {
  display: grid;
  gap: 1px;
}

.contents-stats span,
.contents-stats strong {
  font-size: 9px;
  font-weight: 400;
}

.contents-stats span {
  opacity: 0.5;
}

.chapter-layout {
  display: grid;
  grid-template-columns: 160px minmax(0, var(--text-width)) 160px;
  column-gap: 38px;
  max-width: var(--book-width);
  margin: 0 auto;
  padding: 110px var(--page-gutter) 0;
}

.chapter-outline {
  position: sticky;
  top: calc(var(--header-height) + 28px);
  align-self: start;
  font-size: 9px;
}

.chapter-outline > p {
  margin: 0 0 18px;
}

.chapter-outline ol {
  display: grid;
  gap: 7px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.chapter-outline a {
  display: grid;
  grid-template-columns: 24px 1fr;
  text-decoration: none;
  opacity: 0.42;
  transition: opacity 160ms ease, transform 160ms ease;
}

.chapter-outline a:hover,
.chapter-outline a:focus-visible,
.chapter-outline a.is-active {
  opacity: 1;
}

.chapter-outline a.is-active {
  transform: translateX(4px);
}

.outline-meter {
  width: 1px;
  height: 84px;
  margin-top: 22px;
  background: var(--ink-12);
}

.outline-meter span {
  display: block;
  width: 1px;
  height: 12.5%;
  background: var(--ink);
  transform-origin: top;
  transition: transform 280ms ease;
}

.chapter {
  min-width: 0;
}

.chapter-section {
  position: relative;
  display: block;
  padding: 0 0 112px;
  scroll-margin-top: calc(var(--header-height) + 35px);
}

.section-number {
  position: absolute;
  top: 5px;
  right: calc(100% + 18px);
  font-size: 9px;
  opacity: 0.58;
}

.section-kicker {
  margin: 0 0 16px;
  font-size: 9px;
}

.section-copy h2 {
  max-width: 13ch;
  margin: 0;
  font-size: clamp(40px, 4.4vw, 60px);
  font-weight: 400;
  letter-spacing: -0.06em;
  line-height: 1.02;
}

.prose {
  max-width: 61ch;
  margin-top: 34px;
}

.prose p {
  margin: 0 0 20px;
}

.prose .lead {
  color: var(--ink-dark);
  font-size: 18px;
  line-height: 1.55;
}

.two-column-prose {
  display: block;
  max-width: 61ch;
}

.full-bleed {
  width: min(820px, calc(100vw - 40px));
  margin: 0 0 116px -48px;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}

.dataset-diagram {
  position: relative;
  min-height: 440px;
  padding: 74px 48px 48px;
  overflow: hidden;
}

.dataset-grid {
  display: grid;
  grid-template-columns: 0.7fr 0.7fr 1fr 1.2fr;
  gap: 1px;
  background: var(--ink-28);
}

.dataset-grid span {
  display: grid;
  min-height: 52px;
  place-items: center;
  background: var(--paper);
  font-size: 9px;
  transition: color 250ms ease, background 250ms ease, transform 250ms ease;
}

.dataset-grid span:nth-child(-n + 4) {
  color: var(--paper);
  background: var(--ink);
}

.dataset-diagram.is-animated .dataset-grid span {
  animation: cell-pulse 900ms ease both;
  animation-delay: calc((var(--x) + var(--y)) * 45ms);
}

@keyframes cell-pulse {
  0% {
    color: var(--paper);
    background: var(--ink);
    transform: scale(0.96);
  }
  100% {
    transform: scale(1);
  }
}

.dataset-label {
  position: absolute;
  font-size: 9px;
}

.label-rows {
  top: 50%;
  left: 14px;
  transform: rotate(-90deg) translateX(-50%);
  transform-origin: left top;
}

.label-columns {
  top: 23px;
  left: 50%;
  transform: translateX(-50%);
}

.formula-note {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 7px 20px;
  margin-top: 42px;
  padding: 17px 0;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}

.formula-note span {
  font-size: 9px;
}

.formula-note strong {
  font-size: 14px;
  font-weight: 400;
}

.formula-note p {
  grid-column: 1 / -1;
  margin: 13px 0 0;
  font-size: 12px;
}

.variable-machine {
  display: grid;
  grid-template-columns: 1fr 36px 1fr 36px 1fr;
  align-items: stretch;
  margin-top: 46px;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}

.variable-machine div {
  display: grid;
  min-height: 125px;
  align-content: space-between;
  padding: 13px 8px;
}

.variable-machine span,
.variable-machine strong {
  font-size: 9px;
  font-weight: 400;
}

.variable-machine i,
.pipeline-diagram i {
  position: relative;
}

.variable-machine i::before,
.pipeline-diagram i::before {
  content: "";
  position: absolute;
  top: 50%;
  right: 8px;
  left: 8px;
  height: 1px;
  background: var(--ink);
}

.variable-machine i::after,
.pipeline-diagram i::after {
  content: "";
  position: absolute;
  top: calc(50% - 3px);
  right: 8px;
  width: 6px;
  height: 6px;
  transform: rotate(45deg);
  border-top: 1px solid var(--ink);
  border-right: 1px solid var(--ink);
}

.distribution-diagram {
  position: relative;
  min-height: 360px;
  padding: 58px 42px 36px;
}

.distribution-axis {
  display: flex;
  justify-content: space-between;
  margin: 0 0 26px 38px;
  padding-bottom: 7px;
  border-bottom: 1px solid var(--ink-28);
  font-size: 9px;
}

.distribution-row {
  display: grid;
  grid-template-columns: 38px 1fr;
  align-items: center;
  min-height: 96px;
  border-bottom: 1px solid var(--ink-12);
}

.distribution-row > strong {
  font-size: 17px;
  font-weight: 400;
}

.dot-field {
  position: relative;
  height: 60px;
}

.dot-field i {
  position: absolute;
  top: 50%;
  width: 11px;
  height: 11px;
  border: 1px solid var(--ink);
  background: var(--paper);
  transform: translate(-50%, -50%);
}

.dot-field-tight i:nth-child(1) { left: 39%; }
.dot-field-tight i:nth-child(2) { left: 42%; top: 36%; }
.dot-field-tight i:nth-child(3) { left: 45%; top: 62%; }
.dot-field-tight i:nth-child(4) { left: 47%; top: 42%; }
.dot-field-tight i:nth-child(5) { left: 50%; background: var(--ink); }
.dot-field-tight i:nth-child(6) { left: 52%; top: 65%; }
.dot-field-tight i:nth-child(7) { left: 55%; top: 35%; }
.dot-field-tight i:nth-child(8) { left: 58%; }
.dot-field-tight i:nth-child(9) { left: 61%; top: 60%; }
.dot-field-wide i:nth-child(1) { left: 10%; }
.dot-field-wide i:nth-child(2) { left: 20%; top: 35%; }
.dot-field-wide i:nth-child(3) { left: 30%; top: 63%; }
.dot-field-wide i:nth-child(4) { left: 40%; top: 42%; }
.dot-field-wide i:nth-child(5) { left: 50%; background: var(--ink); }
.dot-field-wide i:nth-child(6) { left: 60%; top: 64%; }
.dot-field-wide i:nth-child(7) { left: 70%; top: 34%; }
.dot-field-wide i:nth-child(8) { left: 80%; }
.dot-field-wide i:nth-child(9) { left: 90%; top: 62%; }

.mean-marker {
  position: absolute;
  top: 77px;
  bottom: 36px;
  left: calc(42px + 38px + (100% - 122px) * 0.5);
  width: 1px;
  border-left: 1px dashed var(--ink);
}

.mean-marker span {
  position: absolute;
  top: -24px;
  left: 7px;
}

blockquote {
  margin: 46px 0 0;
  padding: 4px 0 4px 23px;
  border-left: 5px solid var(--ink);
  font-size: 18px;
  line-height: 1.5;
}

blockquote p {
  max-width: 34ch;
  margin: 0;
}

.comparison-diagram {
  display: grid;
  grid-template-columns: 1fr 38px 1fr 38px 1fr;
  margin-top: 46px;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}

.comparison-group {
  display: grid;
  min-height: 160px;
  align-content: space-between;
  padding: 13px 8px;
}

.comparison-group.result {
  color: var(--paper);
  background: var(--ink);
}

.comparison-group span,
.comparison-group small,
.comparison-operator span {
  font-size: 8px;
}

.comparison-value {
  font-size: 39px;
  line-height: 1;
}

.comparison-operator {
  display: grid;
  place-items: center;
  align-content: center;
}

.comparison-operator strong {
  margin-top: 12px;
  font-size: 23px;
  font-weight: 400;
}

.residual-frame {
  position: relative;
  height: 470px;
  background-image:
    linear-gradient(var(--ink-12) 1px, transparent 1px),
    linear-gradient(90deg, var(--ink-12) 1px, transparent 1px);
  background-size: 12.5% 12.5%;
}

.residual-key {
  position: absolute;
  right: 10px;
  bottom: 9px;
  display: flex;
  gap: 14px;
  padding: 6px;
  background: var(--paper);
  font-size: 8px;
}

.residual-key span {
  display: flex;
  align-items: center;
  gap: 5px;
}

.residual-key i {
  display: block;
  width: 11px;
  height: 6px;
}

.key-point { border: 1px solid var(--ink); }
.key-line { border-top: 2px solid var(--ink); }
.key-dash { border-top: 1px dashed var(--ink); }

.code-plate {
  margin-top: 46px;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}

.code-plate-head {
  display: flex;
  justify-content: space-between;
  padding: 7px 0;
  border-bottom: 1px solid var(--ink-28);
  font-size: 9px;
}

.code-plate pre {
  margin: 0;
  padding: 28px;
  color: var(--paper);
  background: var(--ink);
  font: 14px/1.65 var(--type);
  overflow-x: auto;
}

.code-plate p {
  margin: 0;
  padding: 12px 0;
  border-top: 1px solid var(--ink-28);
  font-size: 11px;
  text-transform: none;
}

.workflow-list {
  margin: 46px 0 0;
  padding: 0;
  border-top: 1px solid var(--ink);
  list-style: none;
}

.workflow-list li {
  display: grid;
  grid-template-columns: 82px minmax(190px, 0.8fr) 1fr;
  gap: 18px;
  align-items: baseline;
  padding: 18px 0;
  border-bottom: 1px solid var(--ink-28);
}

.workflow-list span {
  font-size: 9px;
}

.workflow-list strong {
  font-size: 14px;
  font-weight: 400;
}

.workflow-list p {
  margin: 0;
  font-size: 11px;
}

.pipeline-diagram {
  display: grid;
  grid-template-columns: 1fr 35px 1fr 35px 1fr 35px 1fr;
  min-height: 190px;
}

.pipeline-diagram div {
  display: grid;
  align-content: space-between;
  padding: 14px 8px;
}

.pipeline-diagram span,
.pipeline-diagram small {
  font-size: 8px;
}

.pipeline-diagram strong {
  align-self: center;
  font-size: 12px;
  font-weight: 400;
}

.schedule-list {
  margin-top: 46px;
  border-top: 1px solid var(--ink);
}

.schedule-list article {
  display: grid;
  grid-template-columns: 88px minmax(165px, 0.8fr) 1fr 95px;
  gap: 18px;
  align-items: baseline;
  padding: 17px 0;
  border-bottom: 1px solid var(--ink-28);
}

.schedule-list span,
.schedule-list small {
  font-size: 9px;
}

.schedule-list strong {
  font-size: 14px;
  font-weight: 400;
}

.schedule-list p {
  margin: 0;
  font-size: 11px;
}

.closing-note {
  display: grid;
  grid-template-columns: 72px 1fr;
  gap: 22px;
  margin-top: 58px;
  padding: 20px 0;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}

.closing-note > span {
  font-size: 9px;
}

.closing-note p {
  max-width: 55ch;
  margin: 0;
  font-size: 14px;
}

.closing-note a {
  grid-column: 2;
  width: fit-content;
  margin-top: 12px;
  font-size: 9px;
}

.margin-register {
  position: sticky;
  top: calc(var(--header-height) + 28px);
  display: grid;
  gap: 13px;
  align-self: start;
  font-size: 9px;
}

.margin-register div {
  display: grid;
}

.margin-register span {
  opacity: 0.48;
}

.margin-register strong {
  font-weight: 400;
}

.site-footer {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  align-items: end;
  min-height: 190px;
  margin-top: 40px;
  padding: 36px var(--page-gutter);
  border-top: 1px solid var(--ink-28);
  font-size: 9px;
}

.site-footer div {
  display: grid;
  gap: 4px;
}

.site-footer strong {
  font-size: 13px;
  font-weight: 400;
}

.site-footer p {
  margin: 0;
  text-align: center;
}

.site-footer a {
  justify-self: end;
}

.reveal {
  opacity: 1;
  transform: none;
}

.js .reveal {
  opacity: 0;
  transform: translateY(12px);
}

.js .reveal:target,
.js .reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
  transition:
    opacity 500ms cubic-bezier(0.16, 1, 0.3, 1),
    transform 500ms cubic-bezier(0.16, 1, 0.3, 1);
}

@media (max-width: 1080px) {
  .cover,
  .contents-panel,
  .chapter-layout {
    grid-template-columns: 130px minmax(0, var(--text-width));
  }

  .cover-figure,
  .cover-footer {
    grid-column: 2;
  }

  .contents-stats,
  .margin-register {
    display: none;
  }

  .full-bleed {
    width: min(760px, calc(100vw - 40px));
    margin-left: 0;
  }
}

@media (max-width: 780px) {
  :root {
    --header-height: 48px;
    --page-gutter: 18px;
  }

  body {
    font-size: 14px;
  }

  .site-header {
    grid-template-columns: 1fr auto;
  }

  .header-chapter,
  .chapter-nav {
    display: none;
  }

  .menu-button {
    display: block;
  }

  .cover,
  .contents-panel,
  .chapter-layout {
    display: block;
  }

  .cover {
    padding-top: 58px;
    padding-bottom: 70px;
  }

  .cover-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 11px 22px;
    margin-bottom: 48px;
    padding: 0;
  }

  .cover-title {
    padding-bottom: 30px;
  }

  .cover h1 {
    max-width: 9ch;
    font-size: clamp(51px, 15.5vw, 72px);
  }

  .cover-deck {
    font-size: 15px;
  }

  .cover-intro {
    padding-bottom: 48px;
  }

  .cover-intro .dropcap {
    font-size: 15px;
  }

  .cover-figure {
    width: 100%;
  }

  .technical-figure figcaption {
    grid-template-columns: 1fr auto;
  }

  .technical-figure figcaption span:nth-child(2) {
    display: none;
  }

  .plot-frame {
    height: 390px;
  }

  .figure-controls {
    display: block;
  }

  .figure-controls button {
    margin-top: 10px;
  }

  .cover-footer {
    gap: 5px 17px;
  }

  .contents-panel {
    padding-top: 70px;
    padding-bottom: 78px;
  }

  .contents-list {
    grid-template-columns: 1fr;
  }

  .chapter-layout {
    padding-top: 82px;
  }

  .chapter-outline {
    display: none;
  }

  .chapter-section {
    padding-bottom: 92px;
  }

  .section-number {
    position: static;
    display: block;
    margin-bottom: 8px;
  }

  .section-copy h2 {
    font-size: clamp(36px, 10.8vw, 51px);
  }

  .prose .lead {
    font-size: 16px;
  }

  .full-bleed {
    width: 100%;
    margin-bottom: 94px;
  }

  .dataset-diagram {
    min-height: 370px;
    padding: 66px 25px 32px;
  }

  .dataset-grid span {
    min-height: 43px;
    font-size: 8px;
  }

  .variable-machine,
  .comparison-diagram,
  .pipeline-diagram {
    grid-template-columns: 1fr;
  }

  .variable-machine div,
  .pipeline-diagram div {
    min-height: 103px;
  }

  .variable-machine i,
  .pipeline-diagram i {
    min-height: 31px;
    border-top: 1px solid var(--ink-28);
    border-bottom: 1px solid var(--ink-28);
  }

  .variable-machine i::before,
  .pipeline-diagram i::before {
    top: 6px;
    bottom: 6px;
    left: 50%;
    width: 1px;
    height: auto;
  }

  .variable-machine i::after,
  .pipeline-diagram i::after {
    top: auto;
    right: auto;
    bottom: 6px;
    left: calc(50% - 3px);
    transform: rotate(135deg);
  }

  .distribution-diagram {
    padding: 52px 16px 26px;
  }

  .mean-marker {
    top: 69px;
    bottom: 26px;
    left: calc(16px + 38px + (100% - 70px) * 0.5);
  }

  .comparison-group {
    min-height: 123px;
  }

  .comparison-operator {
    min-height: 43px;
    border-top: 1px solid var(--ink-28);
    border-bottom: 1px solid var(--ink-28);
  }

  .comparison-operator strong {
    margin: 0;
  }

  .residual-frame {
    height: 390px;
  }

  .residual-key {
    display: grid;
    gap: 3px;
  }

  .workflow-list li,
  .schedule-list article {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .closing-note {
    grid-template-columns: 1fr;
    gap: 10px;
  }

  .closing-note a {
    grid-column: auto;
  }

  .site-footer {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .site-footer p {
    text-align: left;
  }

  .site-footer a {
    justify-self: start;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .js .reveal,
  .js .reveal:target,
  .js .reveal.is-visible {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .dataset-diagram.is-animated .dataset-grid span {
    animation: none;
  }
}

/* Teaching book ---------------------------------------------------------- */

.home-cover {
  padding-bottom: 104px;
}

.book-index {
  display: grid;
  grid-template-columns: 160px minmax(0, var(--text-width)) 160px;
  column-gap: 38px;
  max-width: var(--book-width);
  margin: 0 auto;
  padding: 100px var(--page-gutter);
  border-bottom: 1px solid var(--ink-28);
  scroll-margin-top: calc(var(--header-height) + 18px);
}

.index-margin {
  display: grid;
  align-content: start;
  gap: 2px;
  padding-top: 4px;
  font-size: 9px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.index-margin span {
  opacity: 0.5;
}

.index-margin strong {
  font-weight: 400;
}

.index-main {
  grid-column: 2;
}

.index-main h2,
.resource-band h2,
.article-hero h1 {
  margin: 0;
  font-weight: 400;
  letter-spacing: -0.06em;
  line-height: 1.02;
}

.index-main h2,
.resource-band h2 {
  max-width: 13ch;
  font-size: clamp(40px, 4.4vw, 60px);
}

.index-lead {
  max-width: 58ch;
  margin: 30px 0 0;
  color: var(--ink-dark);
  font-size: 17px;
}

.calendar-list {
  margin-top: 48px;
  border-top: 1px solid var(--ink);
}

.calendar-list a {
  display: grid;
  grid-template-columns: 150px minmax(190px, 0.9fr) 1fr;
  gap: 22px;
  align-items: baseline;
  padding: 17px 0;
  border-bottom: 1px solid var(--ink-28);
  text-decoration: none;
}

.calendar-list a:hover strong,
.calendar-list a:focus-visible strong {
  text-decoration: underline;
  text-underline-offset: 4px;
}

.calendar-list time,
.calendar-list span {
  font-size: 10px;
}

.calendar-list strong {
  font-size: 14px;
  font-weight: 400;
}

.calendar-list span {
  opacity: 0.62;
}

.lesson-index a {
  min-height: 108px;
}

.question-list {
  margin: 52px 0 0;
  padding: 0;
  border-top: 1px solid var(--ink);
  list-style: none;
}

.question-list li {
  display: grid;
  grid-template-columns: 76px 1fr;
  gap: 7px 18px;
  padding: 20px 0 22px;
  border-bottom: 1px solid var(--ink-28);
}

.question-list span,
.question-list small {
  font-size: 9px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.question-list span {
  grid-row: 1 / span 2;
  opacity: 0.58;
}

.question-list strong {
  max-width: 54ch;
  font-size: 15px;
  font-weight: 400;
  line-height: 1.55;
}

.question-list small {
  opacity: 0.58;
  text-transform: none;
}

.protocol-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  margin-top: 52px;
  border-top: 1px solid var(--ink);
}

.protocol-grid div {
  min-height: 190px;
  padding: 16px 20px 20px 0;
  border-bottom: 1px solid var(--ink-28);
}

.protocol-grid div:nth-child(odd) {
  padding-right: 28px;
  border-right: 1px solid var(--ink-28);
}

.protocol-grid div:nth-child(even) {
  padding-left: 28px;
}

.protocol-grid span {
  display: block;
  margin-bottom: 28px;
  font-size: 9px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  opacity: 0.58;
}

.protocol-grid strong {
  display: block;
  font-size: 15px;
  font-weight: 400;
}

.protocol-grid p {
  max-width: 35ch;
  margin: 8px 0 0;
  font-size: 11px;
}

.resource-band {
  display: grid;
  grid-template-columns: minmax(240px, 0.7fr) minmax(480px, 1.3fr);
  max-width: var(--book-width);
  margin: 0 auto;
  padding: 100px var(--page-gutter) 120px;
}

.resource-band > div {
  padding-right: 50px;
}

.resource-band nav {
  border-top: 1px solid var(--ink);
}

.resource-band a {
  display: grid;
  grid-template-columns: 90px 1fr;
  gap: 20px;
  padding: 19px 0;
  border-bottom: 1px solid var(--ink-28);
  text-decoration: none;
}

.resource-band a:hover strong,
.resource-band a:focus-visible strong {
  text-decoration: underline;
  text-underline-offset: 4px;
}

.resource-band span {
  font-size: 9px;
  opacity: 0.58;
}

.resource-band strong {
  font-size: 14px;
  font-weight: 400;
}

/* Interior chapters ------------------------------------------------------ */

.article-hero {
  display: grid;
  grid-template-columns: 160px minmax(0, var(--text-width)) 160px;
  column-gap: 38px;
  max-width: var(--book-width);
  margin: 0 auto;
  padding: clamp(64px, 9vw, 118px) var(--page-gutter) 82px;
  border-bottom: 1px solid var(--ink-28);
}

.article-hero-meta {
  display: grid;
  align-content: start;
  gap: 15px;
  padding-top: 5px;
  font-size: 9px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.article-hero-meta div {
  display: grid;
}

.article-hero-meta span {
  opacity: 0.5;
}

.article-hero-meta strong {
  font-weight: 400;
}

.article-hero-copy {
  grid-column: 2;
}

.article-hero-copy > p:first-child {
  margin: 0 0 28px;
  font-size: 9px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.article-hero h1 {
  max-width: 11ch;
  font-size: clamp(52px, 6.2vw, 84px);
}

.article-deck {
  max-width: 48ch;
  margin: 28px 0 0;
  color: var(--ink-dark);
  font-size: 17px;
}

.article-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 22px;
  margin-top: 34px;
}

.article-actions a,
.download-link {
  font-size: 9px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.article-hero-side {
  grid-column: 3;
  align-self: end;
  font-size: 9px;
}

.article-hero-side p {
  margin: 0;
}

.article-layout {
  display: grid;
  grid-template-columns: 160px minmax(0, var(--text-width)) 160px;
  column-gap: 38px;
  max-width: var(--book-width);
  margin: 0 auto;
  padding: 96px var(--page-gutter) 30px;
}

.article-nav {
  position: sticky;
  top: calc(var(--header-height) + 26px);
  align-self: start;
  font-size: 9px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.article-nav > span {
  display: block;
  margin-bottom: 17px;
}

.article-nav a {
  display: block;
  margin-bottom: 7px;
  text-decoration: none;
  opacity: 0.48;
}

.article-nav a:hover,
.article-nav a:focus-visible,
.article-nav a.is-active {
  opacity: 1;
}

.article {
  grid-column: 2;
  min-width: 0;
}

.article-section {
  padding: 0 0 96px;
  scroll-margin-top: calc(var(--header-height) + 32px);
}

.article-section + .article-section {
  padding-top: 4px;
}

.article-section h2 {
  max-width: 14ch;
  margin: 0;
  font-size: clamp(37px, 4vw, 55px);
  font-weight: 400;
  letter-spacing: -0.055em;
  line-height: 1.03;
}

.article-section h3 {
  margin: 38px 0 12px;
  font-size: 17px;
  font-weight: 400;
}

.article-section > p,
.article-prose {
  max-width: 62ch;
}

.article-section > p {
  margin: 27px 0 0;
}

.article-lead {
  color: var(--ink-dark);
  font-size: 18px;
  line-height: 1.55;
}

.article-margin {
  grid-column: 3;
  align-self: start;
  font-size: 9px;
}

.article-margin dl {
  margin: 0;
}

.article-margin div {
  margin-bottom: 16px;
}

.article-margin dt {
  opacity: 0.48;
  text-transform: uppercase;
}

.article-margin dd {
  margin: 0;
}

.learning-list,
.checklist,
.source-list {
  margin: 38px 0 0;
  padding: 0;
  border-top: 1px solid var(--ink);
  list-style: none;
}

.learning-list li,
.checklist li,
.source-list li {
  display: grid;
  grid-template-columns: 34px 1fr;
  gap: 14px;
  padding: 13px 0;
  border-bottom: 1px solid var(--ink-28);
}

.learning-list span,
.checklist span {
  font-size: 9px;
  opacity: 0.55;
}

.learning-list strong,
.checklist strong {
  font-size: 14px;
  font-weight: 400;
}

.session-plan {
  margin-top: 40px;
  border-top: 1px solid var(--ink);
}

.session-plan div {
  display: grid;
  grid-template-columns: 84px 1fr 1.25fr;
  gap: 18px;
  padding: 15px 0;
  border-bottom: 1px solid var(--ink-28);
}

.session-plan time,
.session-plan p {
  font-size: 10px;
}

.session-plan strong {
  font-size: 14px;
  font-weight: 400;
}

.session-plan p {
  margin: 0;
}

.callout,
.prompt-box,
.instructor-note {
  margin-top: 38px;
  padding: 18px 0;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}

.callout > span,
.prompt-box > span,
.instructor-note > span {
  display: block;
  margin-bottom: 15px;
  font-size: 9px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.callout p,
.prompt-box p,
.instructor-note p {
  max-width: 60ch;
  margin: 0;
}

.prompt-box pre {
  margin: 0;
  padding: 24px;
  color: var(--paper);
  background: var(--ink);
  font: 13px/1.65 var(--type);
  white-space: pre-wrap;
}

.table-scroll {
  margin-top: 38px;
  overflow-x: auto;
  border-top: 1px solid var(--ink);
}

.table-scroll table {
  width: 100%;
  min-width: 620px;
  border-collapse: collapse;
  font-size: 10px;
}

.table-scroll th,
.table-scroll td {
  padding: 12px 14px 12px 0;
  border-bottom: 1px solid var(--ink-28);
  text-align: left;
  vertical-align: top;
}

.table-scroll th {
  font-weight: 400;
  text-transform: uppercase;
}

.slide-frame {
  margin-top: 38px;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}

.slide-frame iframe {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  border: 0;
  background: var(--paper-deep);
}

.slide-frame figcaption {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  padding: 9px 0;
  font-size: 9px;
}

.page-turn {
  display: grid;
  grid-template-columns: 1fr 1fr;
  max-width: var(--book-width);
  margin: 0 auto;
  padding: 0 var(--page-gutter) 80px;
}

.page-turn a {
  display: grid;
  min-height: 120px;
  align-content: space-between;
  padding: 17px 0;
  border-top: 1px solid var(--ink);
  text-decoration: none;
}

.page-turn a + a {
  padding-left: 28px;
  border-left: 1px solid var(--ink-28);
}

.page-turn span {
  font-size: 9px;
  opacity: 0.52;
  text-transform: uppercase;
}

.page-turn strong {
  font-size: 16px;
  font-weight: 400;
}

.glossary-list {
  margin-top: 40px;
}

.glossary-list div {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 24px;
  padding: 15px 0;
  border-top: 1px solid var(--ink-28);
}

.glossary-list dt {
  font-size: 12px;
}

.glossary-list dd {
  margin: 0;
}

@media (max-width: 1080px) {
  .book-index,
  .article-hero,
  .article-layout {
    grid-template-columns: 130px minmax(0, var(--text-width));
  }

  .article-hero-side,
  .article-margin {
    display: none;
  }
}

@media (max-width: 780px) {
  .book-index,
  .article-hero,
  .article-layout,
  .resource-band {
    display: block;
  }

  .book-index,
  .resource-band {
    padding-top: 72px;
    padding-bottom: 78px;
  }

  .index-margin {
    display: flex;
    gap: 15px;
    margin-bottom: 40px;
  }

  .calendar-list a,
  .session-plan div {
    grid-template-columns: 1fr;
    gap: 5px;
  }

  .protocol-grid {
    grid-template-columns: 1fr;
  }

  .protocol-grid div,
  .protocol-grid div:nth-child(odd),
  .protocol-grid div:nth-child(even) {
    min-height: 0;
    padding: 18px 0 23px;
    border-right: 0;
  }

  .resource-band > div {
    padding: 0 0 38px;
  }

  .article-hero {
    padding-top: 58px;
  }

  .article-hero-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 10px 20px;
    margin-bottom: 44px;
  }

  .article-hero h1 {
    font-size: clamp(48px, 14vw, 68px);
  }

  .article-layout {
    padding-top: 72px;
  }

  .article-nav {
    display: none;
  }

  .article-section {
    padding-bottom: 80px;
  }

  .question-list li,
  .learning-list li,
  .checklist li {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .question-list span {
    grid-row: auto;
  }

  .page-turn {
    grid-template-columns: 1fr;
  }

  .page-turn a + a {
    padding-left: 0;
    border-left: 0;
  }

  .glossary-list div {
    grid-template-columns: 1fr;
    gap: 6px;
  }
}

/* Book reader ----------------------------------------------------------- */

.article-page {
  --reader-black: #171715;
  --reader-muted: #66645e;
  --reader-rule: rgba(23, 23, 21, 0.19);
  --reader-paper: #fffefb;
  --reader-ground: #efeee8;
  color: var(--reader-black);
  background: var(--reader-ground);
}

.article-page .page-progress {
  display: none;
}

.article-page .site-header {
  color: var(--ink);
  border-color: rgba(165, 28, 48, 0.22);
  background: rgba(239, 238, 232, 0.94);
}

.article-page .mobile-outline {
  color: var(--paper);
}

.article-page main {
  min-width: 0;
}

.article-page .article-layout {
  grid-template-columns:
    minmax(180px, 240px)
    minmax(0, 820px)
    minmax(140px, 180px);
  gap: clamp(28px, 3.2vw, 62px);
  width: min(100%, 1540px);
  max-width: none;
  padding: clamp(34px, 4.5vw, 72px) var(--page-gutter) 50px;
}

.article-page .article {
  grid-column: 2;
  overflow: clip;
  color: var(--reader-black);
  background: var(--reader-paper);
  border: 1px solid rgba(23, 23, 21, 0.14);
  box-shadow:
    0 1px 0 rgba(255, 255, 255, 0.9) inset,
    0 24px 70px rgba(56, 47, 36, 0.08);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 17px;
  line-height: 1.74;
}

.article-page .article-cover {
  grid-template-columns: 105px minmax(0, 1fr) 88px;
  gap: 28px;
  width: 100%;
  max-width: none;
  min-height: clamp(500px, 68vh, 680px);
  margin: 0;
  padding: clamp(62px, 7vw, 94px) clamp(42px, 6vw, 72px) 76px;
  color: var(--reader-black);
  border-bottom: 1px solid var(--reader-rule);
  background:
    linear-gradient(rgba(165, 28, 48, 0.035), rgba(165, 28, 48, 0)) 0 0 / 100% 190px no-repeat,
    var(--reader-paper);
}

.article-page .article-cover .article-hero-meta,
.article-page .article-cover .article-hero-side,
.article-page .article-cover .article-hero-copy > p:first-child,
.article-page .article-actions {
  color: var(--ink);
  font-family: var(--type);
}

.article-page .article-cover .article-hero-meta {
  line-height: 1.55;
}

.article-page .article-cover .article-hero-copy {
  align-self: center;
}

.article-page .article-cover h1 {
  max-width: 10ch;
  color: var(--ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(54px, 5.2vw, 78px);
  font-weight: 400;
  letter-spacing: -0.045em;
  line-height: 0.98;
  text-wrap: balance;
}

.article-page .article-cover .article-deck {
  max-width: 43ch;
  color: var(--reader-black);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 18px;
  line-height: 1.62;
  text-wrap: pretty;
}

.article-page .article-cover .article-actions a {
  color: var(--reader-black);
}

.article-page .article-cover .article-actions a:hover,
.article-page .article-cover .article-actions a:focus-visible {
  color: var(--ink);
}

.article-page .article-section {
  margin-inline: clamp(36px, 6.5vw, 72px);
  padding: clamp(76px, 8vw, 108px) 0;
  border-bottom: 1px solid var(--reader-rule);
}

.article-page .article-section + .article-section {
  padding-top: clamp(76px, 8vw, 108px);
}

.article-page .article-section:last-child {
  border-bottom: 0;
}

.article-page .section-kicker {
  color: var(--ink);
  font-family: var(--type);
  font-size: 10px;
  letter-spacing: 0.04em;
}

.article-page .article-section h2 {
  max-width: 15ch;
  color: var(--ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(38px, 3.6vw, 54px);
  font-weight: 400;
  letter-spacing: -0.035em;
  line-height: 1.02;
  text-wrap: balance;
}

.article-page .article-section h3 {
  color: var(--reader-black);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 21px;
  font-weight: 600;
  letter-spacing: -0.018em;
}

.article-page .article-section > p,
.article-page .article-prose,
.article-page .glossary-list dd,
.article-page .callout p,
.article-page .instructor-note p {
  max-width: 64ch;
  color: var(--reader-black);
  font-family: Georgia, "Times New Roman", serif;
  text-wrap: pretty;
}

.article-page .article-lead {
  color: var(--reader-black);
  font-size: 20px;
  line-height: 1.62;
}

.article-page .article-section a {
  color: var(--reader-black);
  text-decoration-color: rgba(165, 28, 48, 0.55);
}

.article-page .article-section a:hover,
.article-page .article-section a:focus-visible {
  color: var(--ink);
}

.article-page .article-nav {
  counter-reset: reader-nav;
  top: calc(var(--header-height) + 30px);
  max-height: calc(100vh - var(--header-height) - 62px);
  padding: 20px 24px 22px 0;
  overflow-y: auto;
  color: var(--reader-black);
  border-top: 1px solid var(--reader-rule);
  font-family: var(--type);
  font-size: 10px;
  letter-spacing: 0.02em;
  text-transform: none;
  scrollbar-width: thin;
}

.article-page .article-nav > span {
  color: var(--ink);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.article-page .article-nav a {
  counter-increment: reader-nav;
  display: grid;
  grid-template-columns: 25px 1fr;
  gap: 8px;
  margin: 0;
  padding: 7px 0;
  color: var(--reader-black);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 14px;
  letter-spacing: 0;
  line-height: 1.32;
  opacity: 0.58;
  transition:
    color 180ms ease,
    opacity 180ms ease,
    transform 180ms ease;
}

.article-page .article-nav a::before {
  content: counter(reader-nav, decimal-leading-zero);
  color: var(--reader-muted);
  font-family: var(--type);
  font-size: 8px;
  line-height: 2.15;
}

.article-page .article-nav a:hover,
.article-page .article-nav a:focus-visible,
.article-page .article-nav a.is-active {
  color: var(--ink);
  opacity: 1;
  transform: translateX(3px);
}

.article-page .article-nav a.is-active::before {
  color: var(--ink);
}

.article-page .article-margin {
  position: sticky;
  top: calc(var(--header-height) + 30px);
  padding-top: 20px;
  color: var(--reader-black);
  border-top: 1px solid var(--reader-rule);
  font-family: var(--type);
  font-size: 9px;
  line-height: 1.55;
}

.article-page .article-margin dt {
  color: var(--ink);
  opacity: 1;
}

.article-page .article-margin dd {
  color: var(--reader-black);
}

.article-page .learning-list,
.article-page .checklist,
.article-page .source-list,
.article-page .session-plan,
.article-page .table-scroll,
.article-page .callout,
.article-page .prompt-box,
.article-page .instructor-note,
.article-page .slide-frame {
  border-color: var(--reader-black);
}

.article-page .learning-list li,
.article-page .checklist li,
.article-page .source-list li,
.article-page .session-plan div,
.article-page .table-scroll th,
.article-page .table-scroll td,
.article-page .glossary-list div {
  border-color: var(--reader-rule);
}

.article-page .learning-list span,
.article-page .checklist span {
  color: var(--ink);
  font-family: var(--type);
  opacity: 1;
}

.article-page .learning-list strong,
.article-page .checklist strong,
.article-page .source-list strong {
  color: var(--reader-black);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 16px;
  line-height: 1.45;
}

.article-page .session-plan time,
.article-page .session-plan strong,
.article-page .session-plan p,
.article-page .table-scroll,
.article-page .glossary-list dt,
.article-page .slide-frame figcaption {
  color: var(--reader-black);
}

.article-page .session-plan time,
.article-page .table-scroll,
.article-page .glossary-list dt,
.article-page .slide-frame figcaption {
  font-family: var(--type);
}

.article-page .session-plan strong {
  font-family: Georgia, "Times New Roman", serif;
  font-size: 16px;
  font-weight: 600;
}

.article-page .session-plan p {
  font-family: Georgia, "Times New Roman", serif;
  font-size: 14px;
}

.article-page .callout,
.article-page .instructor-note {
  padding: 22px 24px 24px;
  background: rgba(165, 28, 48, 0.045);
}

.article-page .callout > span,
.article-page .prompt-box > span,
.article-page .instructor-note > span {
  color: var(--ink);
  font-family: var(--type);
}

.article-page .prompt-box pre {
  color: #f7f5ef;
  background: var(--reader-black);
}

.article-page .code-plate {
  color: #f7f5ef;
  background: var(--reader-black);
  border-color: var(--reader-black);
}

.article-page .code-plate p {
  color: #f7f5ef;
}

.article-page .protocol-grid {
  color: var(--reader-black);
  border-color: var(--reader-black);
}

.article-page .protocol-grid div {
  border-color: var(--reader-rule);
}

.article-page .protocol-grid span {
  color: var(--ink);
  font-family: var(--type);
  opacity: 1;
}

.article-page .protocol-grid strong,
.article-page .protocol-grid p {
  color: var(--reader-black);
  font-family: Georgia, "Times New Roman", serif;
}

.article-page .page-turn,
.article-page .site-footer {
  color: var(--reader-black);
}

.article-page .page-turn a {
  border-color: var(--reader-black);
}

.article-page .page-turn a + a {
  border-left-color: var(--reader-rule);
}

.article-page .page-turn span,
.article-page .site-footer span {
  color: var(--ink);
  opacity: 1;
}

.reading-rail {
  position: fixed;
  top: calc(var(--header-height) + 30px);
  right: 18px;
  bottom: 32px;
  display: none;
  width: 92px;
  color: var(--reader-black);
  font-family: var(--type);
  z-index: 30;
}

.reading-rail-percent {
  position: absolute;
  top: 0;
  right: 0;
  color: var(--ink);
  font-size: 9px;
  font-variant-numeric: tabular-nums;
}

.reading-rail-track {
  position: absolute;
  top: 28px;
  right: 3px;
  bottom: 0;
  width: 1px;
  background: var(--reader-rule);
}

.reading-rail-fill {
  display: block;
  width: 100%;
  height: 100%;
  background: var(--ink);
  transform: scaleY(0);
  transform-origin: top;
}

.reading-rail-sections {
  position: absolute;
  inset: 28px 0 0;
}

.reading-rail-sections a {
  position: absolute;
  top: calc(var(--rail-position) * 100%);
  right: 0;
  display: flex;
  align-items: center;
  height: 14px;
  color: var(--reader-black);
  text-decoration: none;
  transform: translateY(-7px);
}

.reading-rail-sections a > span {
  display: block;
  width: 10px;
  height: 1px;
  background: var(--reader-muted);
  transition:
    width 180ms ease,
    background 180ms ease;
}

.reading-rail-sections a > em {
  position: absolute;
  right: 24px;
  width: 150px;
  padding: 4px 7px;
  color: var(--reader-black);
  background: rgba(255, 254, 251, 0.96);
  border: 1px solid var(--reader-rule);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 12px;
  font-style: normal;
  line-height: 1.2;
  opacity: 0;
  pointer-events: none;
  transform: translateX(6px);
  transition:
    opacity 160ms ease,
    transform 160ms ease;
}

.reading-rail-sections a:hover > span,
.reading-rail-sections a:focus-visible > span,
.reading-rail-sections a.is-active > span {
  width: 28px;
  background: var(--ink);
}

.reading-rail-sections a:hover > em,
.reading-rail-sections a:focus-visible > em {
  opacity: 1;
  transform: translateX(0);
}

@media (min-width: 1180px) {
  .reading-rail {
    display: block;
  }
}

@media (max-width: 1180px) {
  .article-page .article-layout {
    grid-template-columns: minmax(150px, 190px) minmax(0, 780px);
  }

  .article-page .article-margin {
    display: none;
  }
}

@media (max-width: 860px) {
  .article-page .article-layout {
    display: block;
    padding-top: 24px;
  }

  .article-page .article-nav {
    display: none;
  }

  .article-page .article {
    width: 100%;
  }

  .article-page .article-cover {
    display: block;
    min-height: 0;
    padding: 58px clamp(28px, 8vw, 56px) 68px;
  }

  .article-page .article-cover .article-hero-meta {
    margin-bottom: 48px;
  }

  .article-page .article-cover .article-hero-copy {
    margin-top: 0;
  }

  .article-page .article-cover .article-hero-side {
    display: none;
  }

  .article-page .article-section {
    margin-inline: clamp(25px, 7vw, 52px);
  }
}

@media (max-width: 560px) {
  .article-page .article-layout {
    padding-inline: 12px;
  }

  .article-page .article-cover h1 {
    font-size: clamp(44px, 13vw, 62px);
  }

  .article-page .article-section {
    margin-inline: 24px;
    padding-block: 70px;
  }

  .article-page .article-section + .article-section {
    padding-top: 70px;
  }

  .article-page .article-lead {
    font-size: 18px;
  }
}

/* Editorial book pass --------------------------------------------------- */

:root {
  --book-paper: #fffefb;
  --book-field: #f3f2ee;
  --book-ink: #171714;
  --book-muted: #716f69;
  --book-rule: rgba(23, 23, 20, 0.16);
}

.article-page,
.home-page {
  color: var(--book-ink);
  background: var(--book-field);
}

.article-page .site-header,
.home-page .site-header {
  background: rgba(243, 242, 238, 0.94);
  border-bottom-color: var(--book-rule);
  backdrop-filter: blur(14px);
}

/* The contents belong to the edge of the browser, not to the paper. */
.article-page .article-layout {
  display: block;
  width: 100%;
  max-width: none;
  margin: 0;
  padding: 46px 0 120px;
}

.article-page .article-nav {
  position: fixed;
  top: calc(var(--header-height) + 44px);
  left: clamp(26px, 3vw, 60px);
  width: min(240px, calc(100% - 52px));
  margin: 0;
  padding: 0;
  border: 0;
  counter-reset: reader-nav;
}

.article-page .article-nav > span {
  display: block;
  margin-bottom: 18px;
  color: var(--ink);
  font-size: 9px;
  letter-spacing: 0.1em;
}

.article-page .article-nav a {
  grid-template-columns: 23px 1fr;
  padding: 6px 0;
  color: var(--book-ink);
  font-size: 13px;
  opacity: 0.62;
}

.article-page .article-nav a::before {
  color: var(--book-muted);
}

.article-page .article-nav a:hover,
.article-page .article-nav a:focus-visible,
.article-page .article-nav a.is-active {
  color: var(--ink);
  opacity: 1;
  transform: translateX(2px);
}

.article-page .article {
  width: min(820px, calc(100vw - 560px));
  margin: 0 auto;
  color: var(--book-ink);
  background: var(--book-paper);
  border: 1px solid var(--book-rule);
  box-shadow: 0 18px 50px rgba(23, 23, 20, 0.055);
}

.article-page .article-margin {
  display: none;
}

/* A centered chapter cover, following the reference article. */
.article-page .article-cover {
  display: block;
  min-height: 640px;
  padding: 96px clamp(62px, 9vw, 112px) 84px;
  color: var(--book-ink);
  text-align: center;
  background: var(--book-paper);
  border: 0;
}

.article-page .article-cover .article-hero-meta {
  display: flex;
  justify-content: center;
  gap: 28px;
  margin: 0 auto 92px;
}

.article-page .article-cover .article-hero-meta div {
  display: inline-flex;
  gap: 7px;
  align-items: baseline;
}

.article-page .article-cover .article-hero-meta span,
.article-page .article-cover .article-hero-meta strong {
  color: var(--book-ink);
  font-family: var(--type);
  font-size: 9px;
  font-weight: 400;
  letter-spacing: 0.05em;
}

.article-page .article-cover .article-hero-meta span {
  color: var(--book-muted);
}

.article-page .article-cover .article-hero-copy {
  width: min(100%, 620px);
  margin: 0 auto;
}

.article-page .article-cover .article-hero-copy > p:first-child {
  display: block;
  margin: 0 0 28px;
  color: var(--ink);
  font-family: var(--type);
  font-size: 10px;
  letter-spacing: 0.09em;
}

.article-page .article-cover h1 {
  max-width: 720px;
  margin: 0 auto;
  color: var(--ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(58px, 6.2vw, 92px);
  font-weight: 400;
  letter-spacing: -0.055em;
  line-height: 0.98;
  text-align: center;
}

.article-page .article-cover .article-deck {
  max-width: 590px;
  margin: 32px auto 0;
  color: var(--book-ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 20px;
  line-height: 1.55;
  text-align: center;
}

.article-page .article-cover .article-actions {
  display: flex;
  justify-content: center;
  gap: 28px;
  margin-top: 48px;
}

.article-page .article-cover .article-actions a {
  color: var(--book-ink);
  border-bottom-color: var(--book-ink);
}

.article-page .article-cover .article-hero-side {
  display: none;
}

/* The body reads as one essay. Spacing, rather than boxes, marks sections. */
.article-page .article-section {
  margin: 0;
  padding: 82px clamp(58px, 8vw, 104px) 24px;
  color: var(--book-ink);
  border: 0;
}

.article-page .article-section + .article-section {
  padding-top: 104px;
  border: 0;
}

.article-page .article-section:last-child {
  padding-bottom: 104px;
}

.article-page .article-section.article-subsection {
  padding-top: 46px;
}

.article-page .article-section.article-subsection h2 {
  margin-bottom: 22px;
  color: var(--book-ink);
  font-size: 24px;
  font-weight: 600;
  letter-spacing: -0.015em;
  line-height: 1.22;
}

.article-page .article-section.article-subsection .section-kicker {
  color: var(--book-muted);
}

.article-page .section-kicker {
  margin-bottom: 16px;
  color: var(--ink);
  font-size: 9px;
  letter-spacing: 0.1em;
}

.article-page .article-section h2 {
  max-width: 650px;
  margin: 0 0 32px;
  color: var(--ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(34px, 4vw, 52px);
  font-weight: 400;
  letter-spacing: -0.035em;
  line-height: 1.05;
}

.article-page .article-section h3 {
  margin: 54px 0 18px;
  color: var(--book-ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 22px;
  font-weight: 600;
  line-height: 1.25;
}

.article-page .article-section > p,
.article-page .article-prose,
.article-page .glossary-list dd,
.article-page .callout p,
.article-page .instructor-note p {
  color: var(--book-ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 17px;
  line-height: 1.72;
  text-align: justify;
  text-justify: inter-word;
  hyphens: auto;
}

.article-page .article-section > p + p {
  margin-top: 1.15em;
}

.article-page .article-lead {
  color: var(--book-ink);
  font-size: 20px;
  line-height: 1.65;
}

.article-page .article-section strong {
  color: var(--book-ink);
}

.article-page .article-section a {
  color: var(--book-ink);
  text-decoration-color: var(--ink);
  text-underline-offset: 3px;
}

/* Lists are typography, not components. */
.article-page .learning-list,
.article-page .checklist,
.article-page .source-list {
  display: block;
  margin: 30px 0 36px;
  padding: 0 0 0 1.3rem;
  border: 0;
}

.article-page .learning-list li,
.article-page .checklist li,
.article-page .source-list li {
  display: list-item;
  margin: 0 0 11px;
  padding: 0 0 0 8px;
  border: 0;
  color: var(--book-ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 16px;
  line-height: 1.55;
}

.article-page .learning-list li::marker {
  color: var(--ink);
}

.article-page .learning-list li > span,
.article-page .checklist li > span {
  display: none;
}

.article-page .learning-list strong,
.article-page .checklist strong,
.article-page .source-list strong {
  font-family: Georgia, "Times New Roman", serif;
  font-size: inherit;
  font-weight: 400;
  line-height: inherit;
}

.article-page .checklist {
  list-style: "—  ";
}

.article-page .checklist li::marker {
  color: var(--ink);
}

/* Callout markup is deliberately flattened into ordinary prose. */
.article-page .callout,
.article-page .instructor-note {
  margin: 28px 0;
  padding: 0;
  color: var(--book-ink);
  background: transparent;
  border: 0;
}

.article-page .callout > span,
.article-page .instructor-note > span {
  display: inline;
  margin-right: 0.35em;
  color: var(--book-ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 17px;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: none;
}

.article-page .callout > span::after,
.article-page .instructor-note > span::after {
  content: ".";
}

.article-page .callout > p,
.article-page .instructor-note > p {
  display: inline;
  margin: 0;
}

/* Timings remain useful, but no longer form a boxed dashboard. */
.article-page .session-plan {
  display: block;
  margin: 30px 0 44px;
  padding: 0;
  border: 0;
}

.article-page .session-plan div {
  display: grid;
  grid-template-columns: 62px 118px 1fr;
  gap: 14px;
  align-items: baseline;
  padding: 7px 0;
  border: 0;
}

.article-page .session-plan time {
  color: var(--ink);
  font-size: 9px;
}

.article-page .session-plan strong {
  font-size: 15px;
}

.article-page .session-plan p {
  margin: 0;
  font-size: 15px;
  line-height: 1.45;
  text-align: left;
}

.article-page .protocol-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px 36px;
  margin: 34px 0 44px;
  border: 0;
}

.article-page .protocol-grid div {
  padding: 0;
  border: 0;
}

.article-page .protocol-grid span {
  color: var(--ink);
  font-size: 8px;
}

.article-page .protocol-grid strong {
  display: block;
  margin: 5px 0 3px;
  font-size: 16px;
}

.article-page .protocol-grid p {
  font-size: 15px;
  line-height: 1.45;
}

/* Tables are reserved for real comparisons and kept visually quiet. */
.article-page .table-scroll {
  margin: 34px 0 44px;
  border: 0;
}

.article-page .table-scroll table {
  border-collapse: collapse;
}

.article-page .table-scroll th,
.article-page .table-scroll td {
  padding: 12px 10px;
  color: var(--book-ink);
  border: 0;
  border-bottom: 1px solid var(--book-rule);
}

.article-page .table-scroll th {
  color: var(--ink);
  font-size: 9px;
}

.article-page .table-scroll td {
  font-family: Georgia, "Times New Roman", serif;
  font-size: 14px;
  line-height: 1.45;
}

.article-page .glossary-list {
  margin: 34px 0 46px;
}

.article-page .glossary-list div {
  display: grid;
  grid-template-columns: 130px 1fr;
  gap: 24px;
  padding: 12px 0;
  border: 0;
}

.article-page .glossary-list dt {
  color: var(--book-ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 16px;
  font-weight: 700;
}

.article-page .glossary-list dd {
  margin: 0;
  font-size: 16px;
  line-height: 1.55;
}

/* Code and agent prompts are reading material, not banners. */
.article-page .code-plate,
.article-page .prompt-box {
  margin: 34px 0 26px;
  color: var(--book-ink);
  background: #f4f3ef;
  border: 0;
  letter-spacing: normal;
  text-transform: none;
}

.article-page .code-plate-head,
.article-page .prompt-box > span {
  display: block;
  padding: 14px 18px 0;
  color: var(--book-ink);
  font-family: var(--type);
  font-size: 9px;
  letter-spacing: 0.05em;
  text-transform: none;
}

.article-page .code-plate-head span:first-child {
  display: none;
}

.article-page .code-plate pre,
.article-page .prompt-box pre {
  margin: 0;
  padding: 18px;
  color: var(--book-ink);
  background: transparent;
  border: 0;
  font-size: 13px;
  line-height: 1.65;
  letter-spacing: normal;
  text-transform: none;
}

.article-page .code-plate > p {
  padding: 0 18px 18px;
  color: var(--book-ink);
  font-size: 15px;
}

.article-page .code-notes {
  margin: 24px 0 44px;
}

.article-page .code-notes p {
  margin: 0 0 14px;
  color: var(--book-ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 16px;
  line-height: 1.6;
  text-align: justify;
  text-justify: inter-word;
}

.article-page .slide-frame {
  margin-top: 32px;
  border-color: var(--book-rule);
}

/* A larger reading rail at the far edge. */
.reading-rail {
  top: calc(var(--header-height) + 34px);
  right: 22px;
  bottom: 28px;
  width: 128px;
  color: var(--book-ink);
}

.reading-rail-percent {
  right: 2px;
  font-size: 10px;
}

.reading-rail-track {
  top: 34px;
  right: 4px;
  width: 2px;
  background: var(--book-rule);
}

.reading-rail-sections {
  inset: 34px 0 0;
}

.reading-rail-sections a {
  height: 18px;
  transform: translateY(-9px);
}

.reading-rail-sections a > span {
  width: 15px;
  height: 1px;
}

.reading-rail-sections a > em {
  right: 34px;
  width: 170px;
  padding: 5px 8px;
  background: rgba(255, 254, 251, 0.98);
  border-color: var(--book-rule);
  font-size: 12px;
}

.reading-rail-sections a:hover > span,
.reading-rail-sections a:focus-visible > span,
.reading-rail-sections a.is-active > span {
  width: 38px;
}

/* Homepage: the same book shell, with its own edge contents. */
.home-page .home-outline {
  position: fixed;
  top: calc(var(--header-height) + 44px);
  left: clamp(26px, 3vw, 60px);
  z-index: 20;
  width: min(220px, 17vw);
  font-family: Georgia, "Times New Roman", serif;
}

.home-page .home-outline > span {
  display: block;
  margin-bottom: 18px;
  color: var(--ink);
  font-family: var(--type);
  font-size: 9px;
  letter-spacing: 0.1em;
}

.home-page .home-outline a {
  display: grid;
  grid-template-columns: 23px 1fr;
  gap: 8px;
  padding: 6px 0;
  color: var(--book-ink);
  font-size: 13px;
  line-height: 1.3;
  text-decoration: none;
  opacity: 0.62;
}

.home-page .home-outline a::before {
  color: var(--book-muted);
  font-family: var(--type);
  font-size: 8px;
}

.home-page .home-outline a:nth-of-type(1)::before { content: "01"; }
.home-page .home-outline a:nth-of-type(2)::before { content: "02"; }
.home-page .home-outline a:nth-of-type(3)::before { content: "03"; }
.home-page .home-outline a:nth-of-type(4)::before { content: "04"; }
.home-page .home-outline a:nth-of-type(5)::before { content: "05"; }
.home-page .home-outline a:nth-of-type(6)::before { content: "06"; }
.home-page .home-outline a:nth-of-type(7)::before { content: "07"; }

.home-page .home-outline a:hover,
.home-page .home-outline a:focus-visible,
.home-page .home-outline a.is-active {
  color: var(--ink);
  opacity: 1;
}

.home-page main {
  width: min(940px, calc(100vw - 560px));
  margin: 46px auto 0;
  padding-top: 0;
  color: var(--book-ink);
  background: var(--book-paper);
  border: 1px solid var(--book-rule);
  box-shadow: 0 18px 50px rgba(23, 23, 20, 0.055);
}

.home-page main > section {
  width: 100%;
  margin: 0;
  color: var(--book-ink);
  background: var(--book-paper);
  border: 0;
  box-shadow: none;
}

.home-page .home-cover {
  display: block;
  min-height: 0;
  padding: 88px clamp(54px, 7vw, 92px) 82px;
}

.home-page .cover-meta {
  display: flex;
  justify-content: center;
  gap: 30px;
  margin-bottom: 82px;
  padding: 0;
}

.home-page .cover-meta div {
  display: inline-flex;
  gap: 7px;
  align-items: baseline;
}

.home-page .cover-title {
  max-width: 710px;
  margin: 0 auto;
  text-align: center;
}

.home-page .cover-title > p:first-child {
  color: var(--ink);
}

.home-page .cover-title h1 {
  color: var(--ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(58px, 6.4vw, 92px);
  font-weight: 400;
  letter-spacing: -0.055em;
  line-height: 0.98;
  margin-inline: auto;
  text-align: center;
}

.home-page .cover-deck {
  max-width: 650px;
  margin: 28px auto 0;
  color: var(--book-ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 20px;
  line-height: 1.55;
}

.home-page .cover-intro {
  max-width: 650px;
  margin: 72px auto 0;
  padding: 0;
  border: 0;
}

.home-page .cover-intro p,
.home-page .index-lead,
.home-page .home-prose p,
.home-page .protocol-grid p {
  color: var(--book-ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 17px;
  line-height: 1.72;
  text-align: justify;
  text-justify: inter-word;
  hyphens: auto;
}

.home-page .cover-intro p + p,
.home-page .home-prose p + p {
  margin-top: 1.1em;
}

.home-page .cover-figure {
  width: min(100%, 720px);
  margin: 72px auto 0;
}

.home-page .cover-footer {
  display: flex;
  justify-content: space-between;
  margin-top: 54px;
}

.home-page .book-index,
.home-page .contents-panel,
.home-page .resource-band {
  padding: 72px clamp(54px, 7vw, 92px);
  border: 0;
}

.home-page .home-chapter {
  padding-top: 88px;
  padding-bottom: 88px;
}

.home-page .book-index {
  grid-template-columns: 110px 1fr;
  column-gap: 40px;
}

.home-page .contents-panel {
  display: block;
}

.home-page .contents-heading {
  margin-bottom: 42px;
}

.home-page .contents-heading h2,
.home-page .index-main h2,
.home-page .resource-band h2 {
  color: var(--ink);
  font-family: Georgia, "Times New Roman", serif;
  font-weight: 400;
  letter-spacing: -0.035em;
}

.home-page .home-prose {
  max-width: 650px;
  margin: 0 auto 58px;
}

.home-page .home-prose h2 {
  margin-bottom: 28px;
  color: var(--ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(34px, 4vw, 50px);
  font-weight: 400;
  letter-spacing: -0.035em;
  line-height: 1.08;
}

@media (max-width: 1380px) {
  .article-page .article-nav,
  .home-page .home-outline {
    display: none;
  }

  .article-page .article {
    width: min(820px, calc(100vw - 180px));
  }

  .home-page main {
    width: min(940px, calc(100vw - 180px));
  }
}

@media (max-width: 980px) {
  .article-page .article-layout,
  .home-page main {
    display: block;
    width: min(100%, 820px);
    margin: 0 auto;
    padding: 24px 14px 88px;
  }

  .article-page .article-nav,
  .home-page .home-outline,
  .reading-rail {
    display: none;
  }

  .article-page .article {
    width: 100%;
  }

  .article-page .article-cover {
    min-height: 0;
    padding: 72px clamp(30px, 8vw, 70px) 76px;
  }

  .article-page .article-cover .article-hero-meta {
    flex-wrap: wrap;
    margin-bottom: 64px;
  }

  .article-page .article-section {
    margin: 0;
    padding-inline: clamp(28px, 8vw, 72px);
  }

  .home-page main > section {
    margin: 0;
  }
}

@media (max-width: 620px) {
  .article-page .article-cover .article-hero-meta,
  .home-page .cover-meta {
    gap: 12px 20px;
  }

  .article-page .article-cover h1,
  .home-page .cover-title h1 {
    font-size: clamp(46px, 14vw, 66px);
  }

  .article-page .article-cover .article-deck,
  .home-page .cover-deck {
    font-size: 18px;
  }

  .article-page .article-section {
    padding-block: 66px 12px;
  }

  .article-page .article-section + .article-section {
    padding-top: 82px;
  }

  .article-page .article-section h2 {
    font-size: 36px;
  }

  .article-page .article-section > p,
  .article-page .article-prose,
  .home-page .cover-intro p,
  .home-page .home-prose p {
    font-size: 16px;
    line-height: 1.67;
  }

  .article-page .session-plan div {
    grid-template-columns: 56px 1fr;
  }

  .article-page .session-plan p {
    grid-column: 2;
  }

  .article-page .protocol-grid,
  .article-page .glossary-list div {
    grid-template-columns: 1fr;
  }

  .home-page .home-cover,
  .home-page .book-index,
  .home-page .contents-panel,
  .home-page .resource-band {
    padding-inline: 28px;
  }

  .home-page .book-index {
    display: block;
  }

  .home-page .index-margin {
    margin-bottom: 34px;
  }
}

/* Unified homepage chapters --------------------------------------------- */

.home-page .home-chapter {
  display: block;
  padding: 92px clamp(54px, 7vw, 92px) 104px;
  border-top: 1px solid var(--book-rule);
  scroll-margin-top: calc(var(--header-height) + 18px);
}

.home-page .home-chapter .home-prose {
  width: min(100%, 650px);
  max-width: none;
  margin: 0 auto;
}

.home-page .home-chapter .section-kicker {
  margin: 0 0 18px;
  color: var(--ink);
  font-family: var(--type);
  font-size: 9px;
  letter-spacing: 0.1em;
}

.home-page .home-chapter h2 {
  max-width: 13ch;
  margin: 0 0 30px;
  color: var(--ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(39px, 4.3vw, 54px);
  font-weight: 400;
  letter-spacing: -0.04em;
  line-height: 1.04;
  text-wrap: balance;
}

.home-page .home-chapter .chapter-intro,
.home-page .home-chapter .home-prose > p:not(.section-kicker) {
  max-width: 65ch;
  margin: 0;
  color: var(--book-ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 17px;
  line-height: 1.72;
  text-align: justify;
  text-justify: inter-word;
  hyphens: auto;
}

.home-page .home-chapter .home-prose > p + p {
  margin-top: 1.1em;
}

.home-page .editorial-list {
  display: block;
  margin: 46px 0 0;
  padding: 0;
  border-top: 1px solid var(--book-ink);
  list-style: none;
}

.home-page .editorial-list > li,
.home-page .editorial-list > a {
  margin: 0;
  padding: 0;
  border-bottom: 1px solid var(--book-rule);
}

.home-page .editorial-list > li > a,
.home-page .policy-sequence > li,
.home-page .protocol-sequence > li,
.home-page .editorial-list > a {
  display: grid;
  grid-template-columns: 38px minmax(0, 1fr);
  gap: 18px;
  padding: 22px 0 24px;
  color: var(--book-ink);
  text-decoration: none;
}

.home-page .editorial-list .entry-number {
  padding-top: 4px;
  color: var(--book-muted);
  font-family: var(--type);
  font-size: 9px;
  line-height: 1.4;
}

.home-page .editorial-list .entry-copy {
  display: block;
  min-width: 0;
}

.home-page .editorial-list strong {
  display: block;
  max-width: 54ch;
  color: var(--book-ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 19px;
  font-weight: 600;
  line-height: 1.35;
  text-wrap: pretty;
}

.home-page .editorial-list time,
.home-page .editorial-list small {
  display: block;
  color: var(--book-ink);
}

.home-page .editorial-list time {
  margin: 7px 0 0;
  font-family: var(--type);
  font-size: 10px;
  line-height: 1.5;
}

.home-page .editorial-list small {
  max-width: 70ch;
  margin-top: 8px;
  font-family: Georgia, "Times New Roman", serif;
  font-size: 15px;
  line-height: 1.55;
}

.home-page .editorial-list .entry-copy > small:first-child {
  margin: 0 0 7px;
  color: var(--book-muted);
  font-family: var(--type);
  font-size: 9px;
  letter-spacing: 0.04em;
}

.home-page .editorial-list p {
  max-width: 67ch;
  margin: 9px 0 0;
  color: var(--book-ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 15px;
  line-height: 1.58;
  text-align: left;
}

.home-page .editorial-list a {
  transition: color 180ms ease, transform 180ms ease;
}

.home-page .editorial-list a:hover,
.home-page .editorial-list a:focus-visible {
  color: var(--ink);
  transform: translateX(3px);
}

.home-page .editorial-list a:hover strong,
.home-page .editorial-list a:focus-visible strong {
  color: var(--ink);
}

.home-page .reading-note {
  margin: 40px 0 0;
  padding: 0;
  border: 0;
}

.home-page .reading-note p {
  margin: 0;
  color: var(--book-ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 15px;
  line-height: 1.65;
}

.home-page .reading-note strong {
  color: var(--book-ink);
}

/* Repeated lab protocols read as sequences rather than quadrants. */
.article-page .protocol-grid {
  display: block;
  margin: 34px 0 44px;
  border-top: 1px solid var(--book-rule);
}

.article-page .protocol-grid div {
  display: grid;
  grid-template-columns: 92px minmax(0, 1fr);
  gap: 5px 20px;
  margin: 0;
  padding: 17px 0 19px;
  border: 0;
  border-bottom: 1px solid var(--book-rule);
}

.article-page .protocol-grid span {
  grid-row: 1 / span 2;
  margin: 2px 0 0;
  color: var(--book-muted);
}

.article-page .protocol-grid strong {
  margin: 0;
}

.article-page .protocol-grid p {
  max-width: 48ch;
  margin: 2px 0 0;
}

@media (max-width: 620px) {
  .home-page .home-chapter {
    padding: 72px 28px 82px;
  }

  .home-page .home-chapter h2 {
    font-size: 38px;
  }

  .home-page .home-chapter .chapter-intro,
  .home-page .home-chapter .home-prose > p:not(.section-kicker) {
    font-size: 16px;
    line-height: 1.67;
  }

  .home-page .editorial-list {
    margin-top: 36px;
  }

  .home-page .editorial-list > li > a,
  .home-page .policy-sequence > li,
  .home-page .protocol-sequence > li,
  .home-page .editorial-list > a {
    grid-template-columns: 26px minmax(0, 1fr);
    gap: 11px;
    padding: 19px 0 21px;
  }

  .home-page .editorial-list strong {
    font-size: 18px;
  }

  .article-page .protocol-grid div {
    grid-template-columns: 1fr;
  }

  .article-page .protocol-grid span {
    grid-row: auto;
  }
}

/* Shared book geometry -------------------------------------------------- */

:root {
  --book-panel-width: 940px;
  --book-reading-width: 650px;
}

.article-page .article,
.home-page main,
.library-page main {
  width: min(var(--book-panel-width), calc(100vw - 560px));
}

.article-page .article-section {
  width: min(var(--book-reading-width), calc(100% - 56px));
  margin-inline: auto;
  padding-inline: 0;
}

.article-page .page-turn {
  width: min(var(--book-panel-width), calc(100vw - 560px));
  max-width: none;
  padding-inline: 0;
}

.library-page {
  color: var(--book-ink);
  background: var(--book-field);
}

.library-page .site-header {
  background: rgba(243, 242, 238, 0.94);
  border-bottom-color: var(--book-rule);
  backdrop-filter: blur(14px);
}

.library-page main {
  margin: 46px auto 0;
  color: var(--book-ink);
  background: var(--book-paper);
  border: 1px solid var(--book-rule);
  box-shadow: 0 18px 50px rgba(23, 23, 20, 0.055);
}

.library-page .article-hero,
.library-page .book-index {
  width: 100%;
  max-width: none;
  margin: 0;
  color: var(--book-ink);
  background: var(--book-paper);
  border: 0;
}

.library-page .article-hero {
  display: block;
  min-height: 0;
  padding: 88px clamp(54px, 7vw, 92px) 82px;
  text-align: center;
  border-bottom: 1px solid var(--book-rule);
}

.library-page .article-hero-meta {
  display: flex;
  justify-content: center;
  gap: 30px;
  margin: 0 0 72px;
  padding: 0;
}

.library-page .article-hero-meta div {
  display: inline-flex;
  gap: 7px;
  align-items: baseline;
}

.library-page .article-hero-copy {
  width: min(100%, 650px);
  margin: 0 auto;
}

.library-page .article-hero-copy > p:first-child {
  color: var(--ink);
}

.library-page .article-hero h1 {
  max-width: 11ch;
  margin: 0 auto;
  color: var(--ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(52px, 5.4vw, 76px);
  font-weight: 400;
  letter-spacing: -0.05em;
  line-height: 1;
}

.library-page .article-deck {
  max-width: 590px;
  margin: 28px auto 0;
  color: var(--book-ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 19px;
  line-height: 1.55;
}

.library-page .article-hero-side {
  display: none;
}

.library-page .book-index {
  display: block;
  padding: 88px clamp(54px, 7vw, 92px) 104px;
}

.library-page .book-index > * {
  width: min(100%, var(--book-reading-width));
  margin-inline: auto;
}

.library-page .index-margin {
  margin-bottom: 28px;
}

@media (max-width: 1380px) {
  .article-page .article,
  .home-page main,
  .library-page main,
  .article-page .page-turn {
    width: min(var(--book-panel-width), calc(100vw - 180px));
  }
}

@media (max-width: 980px) {
  .article-page .article-layout {
    width: 100%;
    padding: 24px 14px 88px;
  }

  .article-page .article,
  .home-page main,
  .library-page main,
  .article-page .page-turn {
    width: min(var(--book-panel-width), calc(100vw - 28px));
  }

  .home-page main,
  .library-page main {
    margin-top: 24px;
    padding: 0;
  }
}

@media (max-width: 620px) {
  .article-page .article-section {
    width: calc(100% - 48px);
  }

  .library-page .article-hero,
  .library-page .book-index {
    padding-inline: 28px;
  }

  .library-page .article-hero-meta {
    flex-wrap: wrap;
    gap: 12px 20px;
    margin-bottom: 56px;
  }

  .library-page .article-hero h1 {
    font-size: clamp(44px, 13vw, 62px);
  }
}