@font-face {
  font-family: KaTeX_Main;
  src: url("/katex/fonts/KaTeX_Main-Regular.woff2") format("woff2");
  font-display: swap;
}
:root {
  --ink: #16213a;
  --muted: #626c80;
  --blue: #153fd1;
  --line: #dfe5ef;
  --paper: #fff;
  --wash: #f5f7fb;
  --serif: Georgia, "Times New Roman", serif;
  color-scheme: light;
}
* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
  scroll-padding-top: 110px;
}
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: Arial, Helvetica, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
a {
  color: var(--blue);
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
  text-underline-offset: 4px;
}
button,
a {
  -webkit-tap-highlight-color: transparent;
}
a:focus-visible,
button:focus-visible,
summary:focus-visible {
  outline: 3px solid #668cfa;
  outline-offset: 5px;
}
button {
  font: inherit;
  cursor: pointer;
}
.wrap {
  width: min(1200px, calc(100% - 96px));
  margin-inline: auto;
}
.header {
  min-height: 88px;
  max-width: 1440px;
  margin: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 22px 48px;
  border-bottom: 1px solid var(--line);
}
.brand {
  display: flex;
  align-items: center;
  gap: 22px;
  color: var(--ink);
  white-space: nowrap;
}
.brand:hover {
  text-decoration: none;
}
.brand img {
  object-fit: contain;
}
.brand-divider {
  height: 26px;
  width: 1px;
  background: var(--line);
}
.brand-project {
  font-size: 14px;
}
.header nav {
  display: flex;
  align-items: center;
  gap: 30px;
  font-size: 14px;
}
.header nav a {
  color: var(--ink);
  white-space: nowrap;
}
.header nav a[aria-current] {
  color: var(--blue);
}
.header .nav-source {
  color: var(--blue);
}
.skip {
  position: fixed;
  z-index: 10;
  top: 8px;
  left: 8px;
  background: white;
  padding: 10px;
  transform: translateY(-200%);
}
.skip:focus {
  transform: none;
}
.hero {
  display: grid;
  grid-template-columns: 1.22fr 1fr;
  gap: 92px;
  padding-top: 90px;
  padding-bottom: 86px;
  align-items: center;
}
.eyebrow {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.16em;
  line-height: 1.4;
  color: var(--blue);
  margin: 0 0 24px;
}
.hero h1 {
  font-family: var(--serif);
  font-weight: 400;
  letter-spacing: -0.045em;
  font-size: clamp(52px, 5.8vw, 82px);
  line-height: 1.08;
  margin: 0 0 28px;
}
.hero h1 em {
  font-weight: 400;
  color: var(--blue);
}
.hero-lead {
  font-size: 22px;
  line-height: 1.5;
  max-width: 510px;
  margin: 0 0 16px;
}
.hero-detail {
  max-width: 480px;
  font-size: 16px;
  color: var(--muted);
  margin: 0;
}
.actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 24px;
  margin-top: 30px;
}
.button {
  display: inline-flex;
  gap: 24px;
  align-items: center;
  justify-content: center;
  padding: 12px 20px;
  min-height: 48px;
  font-size: 14px;
  border: 1px solid var(--blue);
  border-radius: 3px;
}
.button.primary {
  background: var(--blue);
  color: #fff;
}
.button.secondary {
  color: var(--blue);
  background: #fff;
}
.button:hover {
  text-decoration: none;
  background: #102f9e;
  color: white;
}
.text-link {
  font-size: 14px;
  font-weight: 500;
}
.sequence {
  margin: 26px 0 0;
  padding: 28px 25px 24px;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.sequence figcaption {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 14px;
  margin-bottom: 26px;
}
.sequence figcaption span:first-child {
  color: var(--muted);
}
.sequence svg {
  display: block;
  width: 100%;
  height: auto;
}
.sequence p {
  font-size: 13px;
  line-height: 1.5;
  color: var(--muted);
  margin: 15px 0 0;
  text-align: center;
}
.proof-strip {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: #fafbfe;
}
.proof-strip .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  min-height: 62px;
  font-size: 13px;
}
.proof-strip span:first-child {
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--muted);
}
.proof-strip a {
  font-size: 13px;
}
.section {
  padding-top: 88px;
  padding-bottom: 88px;
}
.section-head {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 60px;
  margin-bottom: 40px;
}
.section-head .eyebrow {
  margin-bottom: 15px;
}
h2 {
  font-family: var(--serif);
  font-weight: 400;
  letter-spacing: -0.025em;
  font-size: 40px;
  line-height: 1.18;
  margin: 0;
}
.section-head > p {
  max-width: 430px;
  color: var(--muted);
  margin: 0;
  font-size: 17px;
  line-height: 1.7;
}
.theorem-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
}
.theorem-card {
  border: 1px solid var(--line);
  padding: 32px 30px 0;
  display: flex;
  flex-direction: column;
  border-radius: 4px;
}
.card-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}
.index {
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--blue);
  font-weight: 600;
}
.status {
  font-size: 11px;
  color: var(--muted);
}
.theorem-card h3 {
  font-family: var(--serif);
  font-weight: 400;
  font-size: 36px;
  letter-spacing: -0.025em;
  line-height: 1.17;
  margin: 26px 0 20px;
}
.theorem-card > p {
  font-size: 16px;
  color: var(--muted);
  margin: 0;
  max-width: 470px;
}
.equation {
  margin: 20px -4px;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 120px;
  overflow-x: auto;
  overflow-y: hidden;
  font-size: 17px;
}
.equation .katex-display {
  margin: 0.8em 0;
}
.card-bottom {
  border-top: 1px solid var(--line);
  margin-top: auto;
  min-height: 75px;
  padding: 20px 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}
.card-bottom span {
  font-size: 12px;
  color: var(--muted);
}
.card-bottom a {
  font-size: 14px;
  white-space: nowrap;
}
.card-bottom a span {
  color: var(--blue);
  font-size: 14px;
}
.context-band {
  background: var(--wash);
  border-block: 1px solid var(--line);
  padding: 65px 0;
}
.context-grid {
  display: grid;
  grid-template-columns: 0.95fr 1.2fr;
  gap: 100px;
}
.context-grid .eyebrow {
  margin-bottom: 20px;
}
.context-grid .large-copy {
  font-size: 21px;
  color: var(--ink);
  line-height: 1.55;
  margin-top: 0;
}
.context-grid p {
  color: var(--muted);
}
.reading-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 115px;
}
.reading-grid h2 {
  margin-bottom: 25px;
}
.reading-grid > div > p:not(.eyebrow) {
  color: var(--muted);
  max-width: 480px;
}
.reading-steps {
  list-style: none;
  padding: 0;
  margin: 0;
}
.reading-steps li {
  border-bottom: 1px solid var(--line);
  padding: 24px 0;
  display: flex;
  gap: 28px;
}
.reading-steps li:first-child {
  padding-top: 0;
}
.reading-steps li > span {
  font-size: 13px;
  color: var(--blue);
  padding-top: 5px;
}
.reading-steps h3 {
  font-size: 17px;
  font-weight: 500;
  margin: 0 0 6px;
}
.reading-steps p {
  font-size: 15px;
  color: var(--muted);
  margin: 0;
}
.citation-section {
  display: grid;
  grid-template-columns: 1fr 1.15fr;
  gap: 80px;
  padding: 0 0 90px;
}
.citation-section h2 {
  font-size: 30px;
}
.citation-section p:not(.eyebrow) {
  font-size: 15px;
  color: var(--muted);
  max-width: 420px;
}
.citation {
  background: var(--wash);
  border: 1px solid var(--line);
  border-radius: 3px;
  padding: 22px;
  position: relative;
  padding-top: 55px;
}
.citation button {
  border: 0;
  background: transparent;
  color: var(--blue);
  position: absolute;
  top: 15px;
  right: 18px;
  font-size: 12px;
}
.citation pre {
  font-size: 12px;
  line-height: 1.75;
  margin: 0;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
  color: #48536b;
}
.footer {
  padding: 30px 48px;
  border-top: 1px solid var(--line);
  display: flex;
  align-items: center;
  gap: 34px;
  max-width: 1440px;
  margin: auto;
}
.footer img {
  object-fit: contain;
}
.footer p {
  font-size: 12px;
  color: var(--muted);
  margin: 0;
}
.footer > div {
  margin-left: auto;
  display: flex;
  gap: 24px;
  font-size: 12px;
}
.article-wrap {
  display: grid;
  grid-template-columns: 215px minmax(0, 770px);
  gap: 85px;
  padding-block: 65px 100px;
  justify-content: space-between;
}
.toc {
  position: sticky;
  top: 36px;
  align-self: start;
  max-height: calc(100vh - 60px);
  overflow: auto;
  font-size: 14px;
}
.toc .back-link {
  display: block;
  margin-bottom: 36px;
  color: var(--muted);
}
.toc .eyebrow {
  margin-bottom: 16px;
  font-size: 11px;
}
.toc nav {
  display: flex;
  flex-direction: column;
  border-left: 1px solid var(--line);
}
.toc nav a {
  display: block;
  line-height: 1.4;
  font-size: 13px;
  padding: 8px 14px;
  color: var(--muted);
  border-left: 2px solid transparent;
  margin-left: -1px;
}
.toc nav a[aria-current] {
  color: var(--blue);
  border-left-color: var(--blue);
  background: #f5f7ff;
}
.toc-download {
  display: block;
  margin-top: 28px;
  font-size: 13px;
}
.article-header {
  margin-bottom: 46px;
  padding-bottom: 30px;
  border-bottom: 1px solid var(--line);
}
.article-header h1 {
  font-family: var(--serif);
  font-weight: 400;
  font-size: 56px;
  line-height: 1.1;
  letter-spacing: -0.04em;
  margin: 0 0 23px;
}
.article-header .eyebrow {
  font-size: 11px;
}
.article-deck {
  color: var(--muted);
  font-size: 21px;
  line-height: 1.5;
  margin: 0;
}
.article-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 22px;
  font-size: 12px;
  margin-top: 26px;
}
.article-meta > span {
  color: var(--muted);
}
.prose {
  min-width: 0;
  font-size: 17px;
  line-height: 1.8;
}
.prose h2 {
  font-size: 31px;
  margin: 44px 0 18px;
  line-height: 1.22;
  scroll-margin-top: 40px;
}
.prose h3 {
  font-family: var(--serif);
  font-size: 24px;
  font-weight: 400;
  margin: 30px 0 10px;
  line-height: 1.3;
}
.prose p {
  margin: 15px 0;
}
.prose a {
  text-decoration: underline;
  text-decoration-color: #b4c3ec;
  text-underline-offset: 3px;
}
.prose a:hover {
  text-decoration-color: var(--blue);
}
.prose ul,
.prose ol {
  padding-left: 25px;
}
.prose li {
  margin: 10px 0;
}
.prose strong {
  font-weight: 600;
}
.prose code {
  font-size: 0.8em;
  line-height: 1.5;
  background: #f1f4f9;
  color: #35497a;
  padding: 2px 4px;
  border-radius: 2px;
  overflow-wrap: anywhere;
}
.prose pre {
  background: var(--wash);
  padding: 20px;
  overflow: auto;
  line-height: 1.5;
}
.prose pre code {
  padding: 0;
}
.prose blockquote {
  margin: 25px 0;
  padding: 8px 24px;
  border-left: 3px solid var(--blue);
  background: #f6f8fe;
}
.prose blockquote p {
  margin: 10px 0;
}
.prose .katex-display {
  overflow: auto;
  max-width: 100%;
  padding: 6px 0;
  font-size: 0.99em;
}
.prose .katex {
  font-size: 1.1em;
}
.prose .article-next {
  border-top: 1px solid var(--line);
  margin-top: 60px;
  padding-top: 25px;
  display: flex;
  justify-content: space-between;
  gap: 24px;
}
.article-next span {
  font-size: 14px;
  color: var(--muted);
}
.combined > h1 {
  font-family: var(--serif);
  font-weight: 400;
  font-size: 44px;
  line-height: 1.2;
  letter-spacing: -0.025em;
  margin-top: 65px;
}
.chapter-break {
  border: 0;
  border-top: 1px solid var(--line);
  margin-top: 65px;
}
.verification {
  max-width: 1000px;
  padding-block: 70px 90px;
}
.verification .article-header h1 {
  font-size: 60px;
}
.verification .prose {
  max-width: 800px;
}
.records {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  margin-top: 45px;
}
.record {
  padding: 30px;
  border: 1px solid var(--line);
  border-radius: 4px;
}
.record h2 {
  font-size: 32px;
  margin-bottom: 25px;
}
.record dl {
  margin: 0;
}
.record dl > div {
  display: grid;
  grid-template-columns: 180px minmax(0, 1fr);
  gap: 25px;
  padding: 12px 0;
  border-bottom: 1px solid #edf0f5;
  font-size: 14px;
}
.record dl > div:last-child {
  border: 0;
}
.record dt {
  color: var(--muted);
}
.record dd {
  margin: 0;
  overflow-wrap: anywhere;
}
.record code {
  font-size: 12px;
}
details {
  border: 1px solid var(--line);
  padding: 15px 20px;
  margin: 25px 0;
}
summary {
  cursor: pointer;
  color: var(--blue);
  font-size: 15px;
}
table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  font-size: 15px;
}
th,
td {
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--line);
  padding: 12px;
}
th {
  font-weight: 600;
  background: var(--wash);
}
@media (min-width: 1500px) {
  .hero {
    padding-top: 110px;
    padding-bottom: 110px;
  }
}
@media (max-width: 1100px) {
  .header {
    padding-inline: 32px;
  }
  .brand-project,
  .brand-divider {
    display: none;
  }
  .wrap {
    width: calc(100% - 64px);
  }
  .hero {
    gap: 40px;
  }
  .hero h1 {
    font-size: 64px;
  }
  .theorem-card {
    padding: 25px 24px 0;
  }
  .card-top {
    min-height: 40px;
  }
  .card-bottom {
    align-items: flex-start;
    flex-direction: column;
  }
  .context-grid,
  .reading-grid,
  .citation-section {
    gap: 60px;
  }
  .article-wrap {
    grid-template-columns: 175px minmax(0, 1fr);
    gap: 40px;
  }
  .article-header h1 {
    font-size: 47px;
  }
}
@media (max-width: 760px) {
  .header {
    min-height: 76px;
    padding: 19px 24px;
    align-items: center;
    gap: 18px;
  }
  .header .brand img {
    width: 88px;
  }
  .header nav {
    gap: 18px;
    font-size: 12px;
  }
  .header nav .nav-source {
    display: none;
  }
  .wrap {
    width: calc(100% - 40px);
  }
  .hero {
    grid-template-columns: 1fr;
    gap: 30px;
    padding-block: 55px 46px;
  }
  .hero h1 {
    font-size: 62px;
    letter-spacing: -0.045em;
  }
  .hero-lead {
    font-size: 21px;
    max-width: 530px;
  }
  .hero-detail {
    max-width: 510px;
  }
  .eyebrow {
    font-size: 11px;
    margin-bottom: 22px;
  }
  .sequence {
    margin-top: 8px;
    max-width: 500px;
    width: 100%;
    padding: 20px;
    justify-self: center;
  }
  .sequence figcaption {
    margin-bottom: 12px;
  }
  .sequence svg {
    max-height: 235px;
  }
  .proof-strip .wrap {
    display: grid;
    grid-template-columns: 1fr 1fr;
    padding-block: 15px;
    gap: 10px;
    font-size: 12px;
  }
  .proof-strip a {
    font-size: 12px;
  }
  .proof-strip span:first-child {
    font-size: 10px;
  }
  .section {
    padding-block: 54px;
  }
  .section-head {
    display: block;
    margin-bottom: 30px;
  }
  .section-head > p {
    margin-top: 24px;
    font-size: 16px;
    max-width: 100%;
  }
  h2 {
    font-size: 35px;
  }
  .theorem-grid {
    grid-template-columns: 1fr;
    gap: 22px;
  }
  .theorem-card {
    padding: 24px 22px 0;
  }
  .theorem-card h3 {
    font-size: 35px;
    margin-top: 18px;
  }
  .card-top {
    min-height: 0;
  }
  .card-bottom {
    flex-direction: row;
    align-items: center;
  }
  .card-bottom > span {
    max-width: 55%;
  }
  .equation {
    font-size: 16px;
  }
  .context-band {
    padding-block: 45px;
  }
  .context-grid,
  .reading-grid,
  .citation-section {
    grid-template-columns: 1fr;
    gap: 30px;
  }
  .context-grid .large-copy {
    font-size: 20px;
  }
  .reading-steps li:first-child {
    padding-top: 5px;
  }
  .citation-section {
    padding-bottom: 50px;
  }
  .citation-section .eyebrow {
    margin-bottom: 12px;
  }
  .footer {
    padding: 26px 22px;
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 18px;
  }
  .footer p {
    font-size: 11px;
    text-align: right;
  }
  .footer > div {
    grid-column: 1/-1;
    margin: 0;
    justify-content: space-between;
  }
  .article-wrap {
    display: block;
    padding-top: 35px;
  }
  .toc {
    position: static;
    max-height: none;
    border-bottom: 1px solid var(--line);
    margin-bottom: 30px;
    padding-bottom: 25px;
  }
  .toc .back-link {
    margin-bottom: 22px;
  }
  .toc nav {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3px;
  }
  .toc nav a {
    font-size: 12px;
    padding-left: 10px;
  }
  .toc .toc-download {
    margin-top: 16px;
  }
  .article-header h1 {
    font-size: 44px;
  }
  .article-header .eyebrow {
    font-size: 10px;
  }
  .article-deck {
    font-size: 20px;
  }
  .article-meta {
    gap: 14px;
  }
  .prose {
    font-size: 16px;
    line-height: 1.8;
  }
  .prose h2 {
    font-size: 28px;
  }
  .prose h3 {
    font-size: 23px;
  }
  .prose .katex-display {
    font-size: 0.88em;
  }
  .combined > h1 {
    font-size: 38px;
  }
  .record {
    padding: 24px 20px;
  }
  .record dl > div {
    grid-template-columns: 1fr;
    gap: 4px;
  }
  .verification {
    padding-block: 45px;
  }
  .verification .article-header h1 {
    font-size: 46px;
  }
  .record h2 {
    font-size: 29px;
  }
}
@media (max-width: 390px) {
  .header {
    padding-inline: 16px;
  }
  .header nav {
    gap: 12px;
    font-size: 11px;
  }
  .header .brand img {
    width: 76px;
  }
  .hero h1 {
    font-size: 54px;
  }
  .card-top {
    gap: 8px;
  }
  .equation {
    font-size: 14px;
  }
  .actions {
    gap: 18px;
  }
}
.prose {
  overflow-wrap: anywhere;
}
.prose .katex-display > .katex {
  width: max-content;
  min-width: 100%;
}
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}
@media print {
  @page {
    size: A4;
    margin: 20mm 19mm 21mm;
  }
  html {
    scroll-behavior: auto;
  }
  body {
    font-family: Georgia, "Times New Roman", serif;
    color: #111;
    font-size: 10.5pt;
    line-height: 1.5;
  }
  .header,
  .footer,
  .toc,
  .skip,
  .actions,
  .article-next {
    display: none !important;
  }
  .wrap {
    width: 100%;
    max-width: none;
    margin: 0;
  }
  .article-wrap {
    display: block;
    padding: 0;
  }
  .prose {
    font-size: 10.5pt;
    line-height: 1.55;
  }
  .article-header {
    padding-bottom: 18pt;
    margin-bottom: 24pt;
  }
  .article-header h1 {
    font-size: 31pt;
  }
  .article-deck {
    font-size: 13pt;
  }
  .article-header .eyebrow {
    font-size: 8pt;
  }
  .prose h2 {
    font-size: 18pt;
    margin-top: 23pt;
    break-after: avoid;
  }
  .prose h3 {
    font-size: 13pt;
    break-after: avoid;
  }
  .prose p {
    orphans: 3;
    widows: 3;
  }
  .prose a {
    color: #153b91;
    text-decoration: none;
  }
  .prose code {
    font-size: 8pt;
    background: transparent;
  }
  .prose .katex-display {
    overflow: visible;
    font-size: 0.92em;
    break-inside: avoid;
  }
  .prose blockquote {
    background: none;
    border-left: 2px solid #153fd1;
    padding-left: 12pt;
    break-inside: avoid;
  }
  .chapter-break {
    break-before: page;
    border: 0;
    margin: 0;
  }
  .combined > h1 {
    font-size: 27pt;
    margin-top: 0;
  }
  .prose table {
    font-size: 9pt;
  }
  .prose th,
  .prose td {
    padding: 6pt;
  }
  a[href^="https://github.com"] {
    overflow-wrap: anywhere;
  }
}