:root {
  color-scheme: light;
  --paper: #f2efe6;
  --paper-light: #fbf8ef;
  --ink: #17313a;
  --ink-soft: #40565d;
  --grid: #b7c3c3;
  --grid-light: #d8deda;
  --straight: #c64a35;
  --street: #167080;
  --brass: #9a7838;
  --white: #fffdf7;
  --display: "Arial Narrow", "Avenir Next Condensed", "Roboto Condensed", Arial, sans-serif;
  --serif: Charter, "Iowan Old Style", "Palatino Linotype", Georgia, serif;
  --mono: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  --page: min(72rem, calc(100vw - 3rem));
  --copy: 45rem;
}

* {
  box-sizing: border-box;
}

html {
  background: var(--paper);
  color: var(--ink);
  scroll-behavior: smooth;
  scroll-padding-top: 5rem;
}

body {
  margin: 0;
  min-width: 20rem;
  overflow-x: hidden;
  background:
    linear-gradient(rgba(23, 49, 58, .035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(23, 49, 58, .035) 1px, transparent 1px),
    var(--paper);
  background-size: 2rem 2rem;
  font-family: var(--serif);
  font-size: 1.075rem;
  line-height: 1.62;
  text-rendering: optimizeLegibility;
}

img,
svg {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration-color: var(--brass);
  text-decoration-thickness: .12em;
  text-underline-offset: .18em;
}

a:hover {
  color: var(--street);
}

button,
input {
  font: inherit;
}

button {
  color: inherit;
}

:focus-visible {
  outline: .2rem solid var(--straight);
  outline-offset: .2rem;
}

.skip-link {
  position: fixed;
  top: .75rem;
  left: .75rem;
  z-index: 100;
  display: inline-flex;
  min-height: 2.75rem;
  align-items: center;
  transform: translateY(-180%);
  background: var(--ink);
  color: var(--white);
  padding: .65rem 1rem;
  font-family: var(--mono);
  font-size: .8rem;
}

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

.topbar {
  width: var(--page);
  min-height: 4.4rem;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  border-bottom: 1px solid var(--ink);
  font-family: var(--mono);
  font-size: .72rem;
  letter-spacing: .08em;
  text-transform: uppercase;
}

.project-mark,
.language-nav a {
  text-decoration: none;
}

.project-mark {
  display: inline-flex;
  min-height: 2.75rem;
  align-items: center;
  gap: .75rem;
}

.project-mark > span:first-child {
  display: grid;
  width: 2.75rem;
  height: 2.75rem;
  place-items: center;
  border: 1px solid var(--ink);
  background: var(--paper-light);
  font-family: var(--display);
  font-size: 1rem;
  font-weight: 800;
  letter-spacing: 0;
}

.language-nav {
  display: flex;
  align-items: center;
  gap: .25rem;
}

.language-nav a,
.language-nav span {
  display: grid;
  min-width: 2.75rem;
  min-height: 2.75rem;
  place-items: center;
  border: 1px solid transparent;
}

.language-nav [aria-current="page"] {
  border-color: var(--ink);
  background: var(--ink);
  color: var(--paper-light);
}

main {
  width: 100%;
}

.hero {
  width: var(--page);
  margin: 0 auto;
  padding: clamp(3.4rem, 8vw, 7.5rem) 0 2rem;
}

.hero-copy {
  max-width: 61rem;
}

.kicker,
.section-kicker,
.chapter-number,
.board-register,
.output-coordinate,
.output-label,
.source-tab,
.footer-fine {
  font-family: var(--mono);
  font-size: .74rem;
  letter-spacing: .075em;
  line-height: 1.45;
  text-transform: uppercase;
}

.kicker,
.section-kicker {
  margin: 0 0 1rem;
  color: var(--brass);
  font-weight: 700;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1,
h2,
h3 {
  font-family: var(--display);
  font-stretch: condensed;
  letter-spacing: -.025em;
  line-height: .98;
}

h1 {
  max-width: 17ch;
  margin-bottom: 1.5rem;
  font-size: clamp(3.25rem, 8vw, 7.2rem);
  font-weight: 900;
  text-transform: uppercase;
}

h2 {
  max-width: 17ch;
  margin-bottom: 1.5rem;
  font-size: clamp(2.6rem, 5.7vw, 5.1rem);
  font-weight: 850;
}

h3 {
  margin-bottom: .65rem;
  font-size: clamp(1.45rem, 2.6vw, 2.1rem);
}

.deck {
  max-width: 47rem;
  margin-bottom: 2.1rem;
  font-size: clamp(1.25rem, 2.6vw, 1.78rem);
  line-height: 1.42;
}

.deck strong {
  font-family: var(--mono);
  font-size: .94em;
}

.readings {
  position: relative;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  max-width: 59rem;
  margin: 0 0 2rem;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}

.reading {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: .4rem 1rem;
  align-items: end;
  min-width: 0;
  padding: 1.25rem 1.35rem 1.35rem .15rem;
}

.reading + .reading {
  border-left: 1px solid var(--grid);
  padding-left: 1.35rem;
}

.reading strong {
  font-family: var(--mono);
  font-size: clamp(2.5rem, 6vw, 5.4rem);
  font-weight: 650;
  letter-spacing: -.07em;
  line-height: .92;
}

.reading > span:last-child {
  color: var(--ink-soft);
  font-family: var(--display);
  font-size: .8rem;
  font-weight: 800;
  letter-spacing: .055em;
  line-height: 1.15;
  text-transform: uppercase;
}

.reading-rule {
  grid-column: 1 / -1;
  height: .28rem;
  margin-bottom: .35rem;
}

.reading-straight .reading-rule {
  background: var(--straight);
}

.reading-street .reading-rule {
  background: repeating-linear-gradient(90deg, var(--street) 0 2.2rem, transparent 2.2rem 2.65rem);
}

.gap-stamp {
  position: absolute;
  right: 1rem;
  bottom: -1.35rem;
  display: flex;
  align-items: center;
  gap: .75rem;
  margin: 0;
  padding: .3rem .7rem;
  border: 1px solid var(--ink);
  background: var(--paper-light);
  box-shadow: .25rem .25rem 0 var(--brass);
  font-family: var(--mono);
  font-size: .73rem;
  line-height: 1.2;
  text-transform: uppercase;
}

.gap-stamp strong {
  font-size: .9rem;
  letter-spacing: 0;
}

.first-answer {
  max-width: 45rem;
  margin: 2.8rem 0 1rem;
  font-size: clamp(1.2rem, 2.4vw, 1.58rem);
  line-height: 1.45;
}

.first-answer strong {
  font-family: var(--mono);
  font-size: .93em;
}

.credibility {
  max-width: 47rem;
  color: var(--ink-soft);
  font-size: .94rem;
}

.credibility a,
.source-tab a,
.source-list a,
.site-footer a {
  display: inline-flex;
  min-height: 2.75rem;
  align-items: center;
}

.drafting-board {
  position: relative;
  width: min(100%, 68rem);
  margin: clamp(2.7rem, 6vw, 5.5rem) auto 1.6rem;
  padding: clamp(1rem, 3vw, 2rem);
  border: 1px solid var(--ink);
  background:
    linear-gradient(rgba(23, 49, 58, .08) 1px, transparent 1px),
    linear-gradient(90deg, rgba(23, 49, 58, .08) 1px, transparent 1px),
    var(--paper-light);
  background-size: 2.5rem 2.5rem;
  box-shadow: .55rem .55rem 0 rgba(154, 120, 56, .42);
  transform: rotate(-.16deg);
}

.drafting-board::before,
.drafting-board::after {
  position: absolute;
  width: 5rem;
  height: 1.2rem;
  background: rgba(183, 195, 195, .62);
  content: "";
}

.drafting-board::before {
  top: -.55rem;
  left: 8%;
  transform: rotate(-4deg);
}

.drafting-board::after {
  right: 9%;
  bottom: -.48rem;
  transform: rotate(3deg);
}

.board-register {
  position: absolute;
  z-index: 2;
  color: var(--ink-soft);
}

.board-register-a {
  top: 1rem;
  left: 1rem;
}

.board-register-b {
  top: 1rem;
  right: 1rem;
  text-align: right;
}

.route-plan {
  width: 100%;
  margin-top: 1.2rem;
}

.plan-grid path {
  fill: none;
  stroke: var(--grid);
  stroke-width: 2;
  vector-effect: non-scaling-stroke;
}

.plan-grid path:last-child {
  stroke: #839596;
  stroke-width: 5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.route-straight path {
  fill: none;
  stroke: var(--straight);
  stroke-width: 6;
  stroke-linecap: round;
  vector-effect: non-scaling-stroke;
}

.route-straight path:last-child {
  stroke-width: 2;
  stroke-dasharray: 4 5;
}

.route-network path {
  fill: none;
  stroke: var(--street);
  stroke-width: 8;
  stroke-linecap: round;
  stroke-linejoin: round;
  vector-effect: non-scaling-stroke;
}

.endpoints circle {
  fill: var(--paper-light);
  stroke: var(--ink);
  stroke-width: 6;
  vector-effect: non-scaling-stroke;
}

.endpoints text,
.route-labels text,
.compass text {
  fill: var(--ink);
  font-family: var(--mono);
  font-size: 17px;
  font-weight: 700;
  letter-spacing: .04em;
  text-transform: uppercase;
}

.route-labels text:first-child {
  fill: var(--straight);
}

.route-labels text:last-child {
  fill: var(--street);
}

.compass circle {
  fill: rgba(242, 239, 230, .8);
  stroke: var(--brass);
  stroke-width: 3;
}

.compass path {
  fill: var(--brass);
}

.drafting-board figcaption {
  max-width: 51rem;
  margin: -.5rem auto 0;
  padding-top: .85rem;
  border-top: 1px solid var(--grid);
  color: var(--ink-soft);
  font-size: .84rem;
  line-height: 1.5;
}

.scope-ribbon {
  display: grid;
  grid-template-columns: minmax(8rem, .28fr) minmax(0, 1fr);
  gap: 1rem;
  width: min(100%, 68rem);
  margin: 0 auto;
  padding: 1rem 0;
  border-top: 1px solid var(--straight);
  border-bottom: 1px solid var(--straight);
  font-size: .9rem;
}

.scope-ribbon strong {
  font-family: var(--mono);
  font-size: .73rem;
  letter-spacing: .06em;
  text-transform: uppercase;
}

.section-rail {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  width: 100%;
  min-height: 3.25rem;
  align-items: stretch;
  justify-content: center;
  overflow-x: auto;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
  background: rgba(242, 239, 230, .96);
  scrollbar-width: thin;
}

.section-rail a {
  display: grid;
  min-width: 6.25rem;
  min-height: 3.25rem;
  place-items: center;
  padding: .4rem .9rem;
  border-right: 1px solid var(--grid);
  font-family: var(--mono);
  font-size: .68rem;
  letter-spacing: .055em;
  text-decoration: none;
  text-transform: uppercase;
}

.section-rail a:first-child {
  border-left: 1px solid var(--grid);
}

.section-rail a:hover {
  background: var(--ink);
  color: var(--white);
}

.chapter {
  display: grid;
  grid-template-columns: minmax(3rem, .18fr) minmax(0, 1fr);
  gap: clamp(1rem, 4vw, 4.5rem);
  width: var(--page);
  margin: 0 auto;
  padding: clamp(5rem, 11vw, 9rem) 0;
  border-bottom: 1px solid var(--grid);
  scroll-margin-top: 4rem;
}

.chapter-number {
  padding-top: .35rem;
  color: var(--brass);
}

.chapter-number::after {
  display: block;
  width: 100%;
  max-width: 4.5rem;
  height: 1px;
  margin-top: .7rem;
  background: var(--brass);
  content: "";
}

.chapter-body {
  min-width: 0;
}

.lead {
  max-width: var(--copy);
  margin-bottom: 2.3rem;
  font-size: clamp(1.18rem, 2.25vw, 1.55rem);
  line-height: 1.48;
}

.measurement-lines {
  max-width: 56rem;
  border-top: 1px solid var(--ink);
}

.measurement-lines > div {
  position: relative;
  display: grid;
  grid-template-columns: 12rem minmax(0, 1fr);
  gap: 1.5rem;
  padding: 1.4rem 0 1.4rem 2rem;
  border-bottom: 1px solid var(--grid);
}

.measurement-lines h3,
.measurement-lines p {
  margin: 0;
}

.measurement-lines p {
  color: var(--ink-soft);
}

.line-key {
  position: absolute;
  top: 1.15rem;
  left: 0;
  width: .7rem;
  height: calc(100% - 2.3rem);
}

.straight-key {
  background: var(--straight);
}

.street-key {
  background: repeating-linear-gradient(var(--street) 0 1rem, transparent 1rem 1.3rem);
}

.margin-note {
  max-width: 44rem;
  margin: 2rem 0 0 auto;
  padding: 1rem 0 1rem 1.2rem;
  border-left: .35rem solid var(--brass);
  color: var(--ink-soft);
  font-size: .95rem;
}

.matrix-chapter {
  width: 100%;
  padding-right: max(1.5rem, calc((100vw - 72rem) / 2));
  padding-left: max(1.5rem, calc((100vw - 72rem) / 2));
  background: var(--ink);
  color: var(--paper-light);
}

.matrix-chapter .section-kicker,
.matrix-chapter .chapter-number {
  color: #d3b56f;
}

.matrix-chapter .chapter-number::after {
  background: #d3b56f;
}

.explorer {
  max-width: 62rem;
  margin: 2.5rem 0;
  padding: clamp(1rem, 3vw, 2rem);
  border: 1px solid #718387;
  background:
    linear-gradient(rgba(242, 239, 230, .055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(242, 239, 230, .055) 1px, transparent 1px),
    #10262e;
  background-size: 2rem 2rem;
}

.control-row {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) minmax(16rem, .8fr);
  gap: 1.5rem;
}

fieldset {
  min-width: 0;
  margin: 0;
  padding: 0;
  border: 0;
}

legend {
  margin-bottom: .65rem;
  font-family: var(--mono);
  font-size: .72rem;
  letter-spacing: .07em;
  text-transform: uppercase;
}

.choice-strip {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  border: 1px solid #819195;
}

.choice-strip label {
  position: relative;
  min-width: 0;
}

.choice-strip label + label {
  border-left: 1px solid #819195;
}

.choice-strip input {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
}

.choice-strip span {
  display: grid;
  min-height: 3.45rem;
  place-items: center;
  padding: .45rem;
  color: #d9e0dc;
  cursor: pointer;
  font-family: var(--display);
  font-size: .76rem;
  font-weight: 800;
  letter-spacing: .04em;
  line-height: 1.15;
  text-align: center;
  text-transform: uppercase;
}

.choice-strip input:checked + span {
  background: var(--paper-light);
  color: var(--ink);
}

.choice-strip input:focus-visible + span {
  outline: .22rem solid #f08a74;
  outline-offset: -.22rem;
}

.reading-output {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: .35rem 1.5rem;
  margin-top: 2rem;
  padding-top: 1.4rem;
  border-top: 1px solid #819195;
}

.output-coordinate,
.output-label {
  color: #b8c5c3;
}

.output-coordinate {
  align-self: end;
}

.reading-output > strong {
  grid-column: 2;
  grid-row: 1 / span 2;
  align-self: center;
  font-family: var(--mono);
  font-size: clamp(3rem, 7vw, 6.5rem);
  font-weight: 500;
  letter-spacing: -.075em;
  line-height: .9;
}

.output-label {
  grid-column: 1;
}

.output-meter {
  --value: 50.66%;
  grid-column: 1 / -1;
  height: .7rem;
  margin: .9rem 0 .45rem;
  background: #53676b;
}

.output-meter i {
  display: block;
  width: var(--value);
  height: 100%;
  background: var(--street);
}

.output-count {
  grid-column: 1 / -1;
  font-family: var(--mono);
  font-size: .92rem;
}

.output-comparison {
  grid-column: 1 / -1;
  max-width: 51rem;
  color: #cbd4d1;
  font-size: .9rem;
}

.reset-button {
  min-height: 2.75rem;
  margin-top: 1.2rem;
  padding: .5rem .85rem;
  border: 1px solid #819195;
  background: transparent;
  color: var(--paper-light);
  cursor: pointer;
  font-family: var(--mono);
  font-size: .7rem;
  letter-spacing: .04em;
  text-transform: uppercase;
}

.reset-button:hover {
  background: var(--paper-light);
  color: var(--ink);
}

.noscript-note {
  margin: 1rem 0 0;
  color: #cbd4d1;
  font-size: .85rem;
}

.matrix-table-wrap {
  max-width: 62rem;
}

.method-matrix {
  width: 100%;
  table-layout: fixed;
  border-collapse: collapse;
  font-family: var(--mono);
  font-size: .82rem;
}

.method-matrix caption {
  margin-bottom: .75rem;
  color: #cbd4d1;
  font-family: var(--serif);
  font-size: .9rem;
  text-align: left;
}

.method-matrix th,
.method-matrix td {
  border: 1px solid #718387;
  text-align: center;
  vertical-align: middle;
}

.method-matrix th {
  padding: .55rem;
  font-weight: 600;
}

.method-matrix thead th {
  color: #d3b56f;
  font-size: .7rem;
  letter-spacing: .05em;
  text-transform: uppercase;
}

.method-matrix th:first-child {
  width: 38%;
  text-align: left;
}

.method-matrix td {
  padding: 0;
}

.method-matrix button {
  width: 100%;
  min-height: 3.25rem;
  padding: .35rem .15rem;
  border: 0;
  background: transparent;
  color: var(--paper-light);
  cursor: pointer;
  font-family: var(--mono);
  font-size: inherit;
}

.method-matrix button:hover,
.method-matrix button.is-active {
  background: var(--street);
  color: #fff;
}

.source-tab {
  max-width: 62rem;
  margin: .75rem 0 0;
  color: #b8c5c3;
  text-transform: none;
}

.boundary-note {
  max-width: 53rem;
  margin-top: 2.3rem;
  padding: 1rem 1.1rem;
  border-left: .4rem solid #d3b56f;
  background: rgba(242, 239, 230, .06);
  color: #dbe1de;
  font-size: .92rem;
}

.calculation-sheet {
  max-width: 49rem;
  padding: 1rem 1.4rem;
  border: 1px solid var(--ink);
  background: var(--paper-light);
  box-shadow: .45rem .45rem 0 var(--grid);
  font-family: var(--mono);
}

.calculation-sheet p {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 1rem;
  margin: 0;
  padding: .9rem 0;
  border-bottom: 1px dotted var(--grid);
}

.calculation-sheet span {
  align-self: center;
  font-family: var(--serif);
}

.calculation-sheet strong {
  font-size: clamp(1.15rem, 3vw, 1.7rem);
}

.calculation-sheet .calculation-result {
  margin-top: .2rem;
  border-top: 2px solid var(--ink);
  border-bottom: 0;
  color: var(--street);
}

.rounding-guard {
  max-width: 49rem;
  margin-top: 2rem;
  padding-left: 1.2rem;
  border-left: .35rem solid var(--straight);
}

.rounding-guard p {
  margin-bottom: .8rem;
}

.threshold-callout {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: .6rem 1.2rem;
  max-width: 55rem;
  margin-top: 3rem;
  padding: 1rem 0;
  border-top: 1px solid var(--street);
  border-bottom: 1px solid var(--street);
  font-family: var(--mono);
  font-size: .78rem;
  text-transform: uppercase;
}

.threshold-callout strong {
  color: var(--street);
  font-size: clamp(1.7rem, 4vw, 3rem);
  letter-spacing: -.05em;
}

.centroid-notation {
  max-width: 49rem;
  padding: 1rem;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}

.centroid-notation svg {
  width: 100%;
}

.area-shape {
  fill: rgba(183, 195, 195, .2);
  stroke: var(--ink);
  stroke-width: 3;
}

.people-marks circle {
  fill: var(--brass);
}

.centroid-rays path {
  fill: none;
  stroke: var(--grid);
  stroke-dasharray: 4 5;
  stroke-width: 2;
}

.centroid-point {
  fill: var(--straight);
  stroke: var(--paper-light);
  stroke-width: 4;
}

.notation-arrow {
  fill: none;
  stroke: var(--ink);
  stroke-width: 3;
}

.notation-equals,
.notation-sub {
  fill: var(--ink);
  font-family: var(--mono);
}

.notation-equals {
  font-size: 28px;
  font-weight: 700;
}

.notation-sub {
  font-size: 17px;
}

.limits-ledger {
  max-width: 58rem;
  margin: 2rem 0 0;
  border-top: 1px solid var(--ink);
}

.limits-ledger > div {
  display: grid;
  grid-template-columns: minmax(9rem, .34fr) minmax(0, 1fr);
  gap: 1.5rem;
  padding: 1.1rem 0;
  border-bottom: 1px solid var(--grid);
}

.limits-ledger dt {
  font-family: var(--display);
  font-size: 1.05rem;
  font-weight: 850;
  letter-spacing: .02em;
  text-transform: uppercase;
}

.limits-ledger dd {
  margin: 0;
  color: var(--ink-soft);
}

.scope-stop {
  max-width: 58rem;
  margin: 2rem 0 0;
  padding: 1rem;
  border: 1px solid var(--straight);
  font-size: .92rem;
}

.method-ledger {
  max-width: 56rem;
  margin: 2rem 0 0;
  padding: 0;
  border-top: 1px solid var(--ink);
  list-style: none;
}

.method-ledger li {
  display: grid;
  grid-template-columns: 4rem minmax(0, 1fr);
  gap: 1.3rem;
  padding: 1.3rem 0;
  border-bottom: 1px solid var(--grid);
}

.method-ledger li > span {
  color: var(--brass);
  font-family: var(--mono);
  font-size: 1rem;
}

.method-ledger strong {
  font-family: var(--display);
  font-size: 1.15rem;
  letter-spacing: .02em;
  text-transform: uppercase;
}

.method-ledger p {
  margin: .25rem 0 0;
  color: var(--ink-soft);
}

.reproduction-note {
  max-width: 56rem;
  margin-top: 2rem;
  padding: 1rem 1.2rem;
  border-left: .4rem solid var(--street);
  background: rgba(22, 112, 128, .07);
  font-size: .92rem;
}

.source-list {
  max-width: 58rem;
  margin: 2rem 0 0;
  padding: 0;
  border-top: 1px solid var(--ink);
  list-style: none;
}

.source-list li {
  display: grid;
  grid-template-columns: 10rem minmax(0, 1fr);
  gap: .25rem 1.5rem;
  padding: 1.25rem 0;
  border-bottom: 1px solid var(--grid);
  overflow-wrap: anywhere;
}

.source-list li > span {
  grid-row: 1 / span 2;
  color: var(--brass);
  font-family: var(--mono);
  font-size: .68rem;
  letter-spacing: .06em;
  text-transform: uppercase;
}

.source-list a {
  font-weight: 700;
}

.source-list small {
  color: var(--ink-soft);
  font-size: .82rem;
}

.source-policy {
  max-width: 48rem;
  margin-top: 2rem;
  color: var(--ink-soft);
  font-size: .9rem;
}

.site-footer {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 1rem 3rem;
  width: var(--page);
  margin: 0 auto;
  padding: 3rem 0 4rem;
  font-size: .88rem;
}

.not-found {
  width: var(--page);
  min-height: 100svh;
  margin: 0 auto;
  padding: clamp(5rem, 14vw, 10rem) 0;
}

.not-found h1 {
  max-width: 12ch;
}

.not-found > p:not(.kicker) {
  max-width: 38rem;
  font-size: 1.15rem;
}

.back-link {
  display: inline-grid;
  min-height: 2.75rem;
  align-items: center;
  padding: .55rem .9rem;
  border: 1px solid var(--ink);
  background: var(--paper-light);
  font-family: var(--mono);
  font-size: .75rem;
  letter-spacing: .04em;
  text-decoration: none;
  text-transform: uppercase;
}

.site-footer p {
  margin-bottom: 0;
}

.footer-fine {
  grid-column: 1 / -1;
  padding-top: 1rem;
  border-top: 1px solid var(--grid);
  color: var(--ink-soft);
  text-transform: none;
}

@media (min-width: 1100px) {
  .hero {
    padding-top: 4rem;
  }

  .hero-copy {
    display: grid;
    grid-template-areas:
      "kicker kicker"
      "title deck"
      "title readings"
      "title answer"
      "title credibility";
    grid-template-columns: minmax(0, 1.12fr) minmax(27rem, .88fr);
    gap: 0 3.5rem;
    max-width: none;
  }

  .hero-copy .kicker {
    grid-area: kicker;
  }

  .hero-copy h1 {
    grid-area: title;
    align-self: start;
    margin-bottom: 0;
    font-size: clamp(4.4rem, 5.8vw, 5.5rem);
  }

  .hero-copy .deck {
    grid-area: deck;
    margin: 0 0 1.25rem;
    font-size: 1.42rem;
  }

  .hero-copy .readings {
    grid-area: readings;
    width: 100%;
    margin-bottom: 1rem;
  }

  .hero-copy .reading {
    grid-template-columns: 1fr;
    align-content: end;
    gap: .25rem;
    padding: 1rem .75rem 1.1rem .15rem;
  }

  .hero-copy .reading + .reading {
    padding-left: .75rem;
  }

  .hero-copy .reading strong {
    font-size: 3.45rem;
  }

  .hero-copy .first-answer {
    grid-area: answer;
    margin: 1.55rem 0 .25rem;
    font-size: 1.2rem;
  }

  .hero-copy .credibility {
    grid-area: credibility;
    margin: 0;
  }
}

@media (max-width: 780px) {
  :root {
    --page: min(100% - 2rem, 72rem);
  }

  body {
    font-size: 1rem;
  }

  .hero {
    padding-top: 3.4rem;
  }

  h1 {
    font-size: clamp(3rem, 15vw, 5.3rem);
  }

  .reading {
    grid-template-columns: 1fr;
    align-content: end;
    gap: .35rem;
    padding-right: .75rem;
  }

  .reading + .reading {
    padding-left: .75rem;
  }

  .reading strong {
    font-size: clamp(2.25rem, 11vw, 4rem);
  }

  .gap-stamp {
    right: .4rem;
  }

  .drafting-board {
    padding-top: 2.4rem;
  }

  .route-labels text,
  .endpoints text {
    font-size: 20px;
  }

  .scope-ribbon {
    grid-template-columns: 1fr;
    gap: .35rem;
  }

  .section-rail {
    justify-content: flex-start;
  }

  .chapter,
  .matrix-chapter {
    grid-template-columns: 1fr;
    gap: 1.4rem;
    padding-top: 5rem;
    padding-bottom: 5rem;
  }

  .chapter-number {
    display: flex;
    align-items: center;
    gap: .65rem;
  }

  .chapter-number::after {
    width: 3.5rem;
    margin: 0;
  }

  .measurement-lines > div {
    grid-template-columns: 1fr;
    gap: .55rem;
  }

  .control-row {
    grid-template-columns: 1fr;
  }

  .reading-output {
    grid-template-columns: 1fr;
  }

  .reading-output > strong {
    grid-column: 1;
    grid-row: auto;
    margin: .35rem 0;
    justify-self: start;
  }

  .output-coordinate,
  .output-label,
  .output-meter,
  .output-count,
  .output-comparison {
    grid-column: 1;
  }

  .method-matrix {
    font-size: .7rem;
  }

  .method-matrix th {
    padding: .35rem .2rem;
  }

  .method-matrix th:first-child {
    width: 40%;
  }

  .calculation-sheet p {
    grid-template-columns: 1fr;
    gap: .2rem;
  }

  .limits-ledger > div,
  .source-list li {
    grid-template-columns: 1fr;
    gap: .45rem;
  }

  .source-list li > span {
    grid-row: auto;
  }

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

  .footer-fine {
    grid-column: 1;
  }
}

@media (max-width: 420px) {
  :root {
    --page: calc(100% - 1.25rem);
  }

  .project-mark > span:last-child {
    display: none;
  }

  .hero {
    padding-top: 2.2rem;
  }

  .kicker {
    margin-bottom: .7rem;
    font-size: .63rem;
  }

  h1 {
    margin-bottom: 1rem;
    font-size: clamp(2.75rem, 12.7vw, 3.3rem);
  }

  .deck {
    margin-bottom: 1.25rem;
    font-size: 1.03rem;
  }

  .readings {
    margin-bottom: 1.5rem;
  }

  .reading {
    padding-top: .8rem;
    padding-bottom: .9rem;
  }

  .reading strong {
    font-size: 2.25rem;
  }

  .reading > span:last-child {
    font-size: .66rem;
  }

  .gap-stamp {
    bottom: -1.15rem;
    padding: .2rem .45rem;
    font-size: .62rem;
  }

  .gap-stamp strong {
    font-size: .74rem;
  }

  .first-answer {
    margin: 2rem 0 .55rem;
    font-size: 1.02rem;
  }

  .credibility {
    font-size: .78rem;
    line-height: 1.45;
  }

  .drafting-board {
    box-shadow: .3rem .3rem 0 rgba(154, 120, 56, .42);
  }

  .board-register {
    font-size: .6rem;
  }

  .explorer {
    padding: .7rem;
  }

  .choice-strip span {
    padding: .35rem .15rem;
    font-size: .63rem;
  }

  .method-matrix {
    font-size: .62rem;
  }

  .method-matrix th:first-child {
    width: 37%;
  }

  .method-matrix button {
    font-size: .62rem;
  }

  .centroid-notation {
    padding: .25rem;
  }
}

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

  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
}

@media (forced-colors: active) {
  .reading-rule,
  .line-key,
  .output-meter i {
    forced-color-adjust: none;
  }
}

@media print {
  .topbar,
  .section-rail,
  .reset-button,
  .skip-link {
    display: none;
  }

  body {
    background: #fff;
    color: #000;
  }

  .hero,
  .chapter,
  .matrix-chapter,
  .site-footer {
    width: 100%;
    padding: 2rem 0;
  }

  .matrix-chapter {
    background: #fff;
    color: #000;
  }

  a {
    color: #000;
  }
}