:root {
  --ink: #111b24;
  --ink-soft: #46515a;
  --table: #d7fb3f;
  --paper: #f3f2e9;
  --paper-deep: #e4e2d5;
  --signal: #ff5733;
  --select: #b8d9ff;
  --line: rgba(17, 27, 36, 0.24);
  --focus: #005fcc;
  --measure: 42rem;
  --sans: "Onest", "Segoe UI", Arial, sans-serif;
  --serif: "Brygada 1918", Charter, "Iowan Old Style", Georgia, serif;
}

* {
  box-sizing: border-box;
}

html {
  color: var(--ink);
  background: var(--table);
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 18rem;
  background:
    linear-gradient(90deg, transparent 0 3.05rem, rgba(17, 27, 36, 0.18) 3.05rem 3.12rem, transparent 3.12rem),
    repeating-linear-gradient(0deg, transparent 0 31px, rgba(17, 27, 36, 0.08) 31px 32px),
    var(--table);
  font-family: var(--serif);
}

a {
  color: inherit;
  text-decoration-color: var(--signal);
  text-decoration-thickness: 0.12em;
  text-underline-offset: 0.18em;
}

a:hover {
  text-decoration-thickness: 0.2em;
}

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

.skip-link {
  position: fixed;
  z-index: 20;
  top: 0.65rem;
  left: 0.65rem;
  padding: 0.65rem 0.85rem;
  color: #fff;
  background: var(--ink);
  font: 700 0.8rem/1 var(--sans);
  transform: translateY(-180%);
}

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

.site-top {
  position: sticky;
  z-index: 10;
  top: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 3.1rem;
  padding: 0.55rem clamp(0.85rem, 3vw, 2.6rem);
  color: #fff;
  background: var(--ink);
  border-bottom: 4px solid var(--signal);
  font: 650 0.76rem/1.2 var(--sans);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.home-link {
  text-decoration: none;
}

.language-nav {
  display: flex;
  gap: 0.45rem;
  overflow-x: auto;
}

.language-link {
  min-width: 2.4rem;
  padding: 0.45rem 0.6rem;
  text-align: center;
  text-decoration: none;
  border: 1px solid rgba(255, 255, 255, 0.48);
}

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

.light-table {
  width: min(100% - clamp(1rem, 4vw, 5rem), 82rem);
  margin: clamp(1rem, 4vw, 3.5rem) auto 5rem;
  background: var(--paper);
  border: 1px solid var(--ink);
  box-shadow: 0.7rem 0.7rem 0 var(--ink);
}

.article-head {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(14rem, 22rem);
  min-height: min(76vh, 48rem);
  overflow: hidden;
  border-bottom: 1px solid var(--ink);
}

.article-head::before,
.article-head::after {
  position: absolute;
  content: "";
  pointer-events: none;
}

.article-head::before {
  inset: 1.2rem;
  border: 1px solid var(--line);
  background:
    linear-gradient(var(--line), var(--line)) 50% 0 / 1px 100% no-repeat,
    linear-gradient(90deg, var(--line), var(--line)) 0 50% / 100% 1px no-repeat;
}

.article-head::after {
  width: clamp(12rem, 28vw, 25rem);
  aspect-ratio: 1;
  right: clamp(1rem, 5vw, 5rem);
  bottom: clamp(-7rem, -8vw, -3rem);
  border: clamp(1.1rem, 3vw, 2.5rem) solid rgba(184, 217, 255, 0.7);
  border-radius: 50%;
}

.head-copy {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: clamp(2.8rem, 8vw, 7rem) clamp(1.4rem, 6vw, 6rem) clamp(2rem, 5vw, 4rem);
}

.eyebrow,
.article-meta,
.head-code,
.chapter-code,
.operation-strip,
.formula,
.status,
.references h2,
.related h2,
.forthcoming h2,
.article-foot {
  font-family: var(--sans);
}

.eyebrow {
  margin: 0 0 2rem;
  font-size: clamp(0.72rem, 1.5vw, 0.86rem);
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

h1 {
  max-width: 10ch;
  margin: 0;
  font-size: clamp(3.25rem, 9vw, 8.7rem);
  font-weight: 500;
  line-height: 0.82;
  letter-spacing: -0.055em;
  overflow-wrap: break-word;
  hyphens: auto;
  text-wrap: balance;
}

.article-subtitle {
  max-width: 34rem;
  margin: clamp(2rem, 6vw, 5rem) 0 1rem;
  font-size: clamp(1.15rem, 2.1vw, 1.65rem);
  line-height: 1.25;
  text-wrap: pretty;
}

.article-meta {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.82rem;
  line-height: 1.5;
}

.head-index {
  position: relative;
  z-index: 1;
  display: grid;
  align-content: end;
  gap: 1px;
  padding: 1.2rem;
  background: rgba(215, 251, 63, 0.74);
  border-left: 1px solid var(--ink);
}

.head-code {
  display: grid;
  grid-template-columns: 2.4rem 1fr;
  gap: 0.8rem;
  padding: 1rem 0.8rem;
  background: rgba(243, 242, 233, 0.88);
  border-top: 1px solid var(--ink);
  font-size: 0.78rem;
  font-weight: 650;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.head-code b {
  color: var(--signal);
}

.prelude {
  display: grid;
  grid-template-columns: 11rem minmax(0, var(--measure));
  justify-content: center;
  gap: clamp(1.4rem, 5vw, 5rem);
  padding: clamp(3rem, 8vw, 7rem) clamp(1.2rem, 5vw, 5rem);
  border-bottom: 1px solid var(--ink);
}

.prelude-mark {
  position: sticky;
  top: 5rem;
  align-self: start;
  width: 8rem;
  height: 8rem;
  display: grid;
  place-items: center;
  color: var(--paper);
  background: var(--signal);
  font: 750 0.75rem/1.35 var(--sans);
  letter-spacing: 0.12em;
  text-align: center;
  text-transform: uppercase;
  clip-path: polygon(0 0, 88% 0, 100% 12%, 100% 100%, 12% 100%, 0 88%);
}

.prose p,
.prelude-copy p {
  margin: 0 0 1.25em;
  font-size: clamp(1.04rem, 0.98rem + 0.22vw, 1.2rem);
  line-height: 1.68;
  text-align: justify;
  text-wrap: pretty;
  hyphens: auto;
  orphans: 3;
  widows: 3;
}

.prelude-lead {
  float: left;
  margin: 0.07em 0.12em 0 0;
  color: var(--signal);
  font-size: 4.3em;
  font-weight: 500;
  line-height: 0.76;
}

.operation-strip {
  display: flex;
  align-items: stretch;
  overflow-x: auto;
  color: #fff;
  background: var(--ink);
  border-bottom: 4px solid var(--select);
  scrollbar-color: var(--signal) var(--ink);
}

.operation-strip span {
  flex: 0 0 auto;
  padding: 1rem 1.1rem;
  border-right: 1px solid rgba(255, 255, 255, 0.24);
  font-size: 0.72rem;
  font-weight: 650;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.operation-strip span::after {
  margin-left: 1.1rem;
  color: var(--table);
  content: "→";
}

.operation-strip span:last-child::after {
  color: var(--signal);
  content: "↻";
}

.chapter {
  display: grid;
  grid-template-columns: minmax(9rem, 13rem) minmax(0, var(--measure));
  justify-content: center;
  gap: clamp(1.4rem, 5vw, 5rem);
  padding: clamp(3.4rem, 9vw, 8rem) clamp(1.2rem, 5vw, 5rem);
  border-bottom: 1px solid var(--ink);
}

.chapter:nth-of-type(even) {
  background:
    linear-gradient(105deg, rgba(184, 217, 255, 0.42) 0 15%, transparent 15% 100%),
    var(--paper);
}

.chapter-label {
  align-self: start;
  min-width: 0;
}

.chapter-code {
  display: inline-block;
  margin: 0 0 1rem;
  padding: 0.42rem 0.55rem;
  color: var(--paper);
  background: var(--ink);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.chapter h2 {
  max-width: 100%;
  margin: 0;
  font-size: clamp(1.55rem, 3vw, 2.45rem);
  font-weight: 500;
  line-height: 1.05;
  letter-spacing: -0.025em;
  overflow-wrap: anywhere;
  hyphens: auto;
  text-wrap: balance;
}

.formula {
  position: relative;
  margin: 2.1rem 0 2.4rem;
  padding: 1.1rem 1.2rem 1.1rem 2.6rem;
  overflow-x: auto;
  color: #fff;
  background: var(--ink);
  border-right: 0.55rem solid var(--signal);
  font-size: clamp(0.78rem, 1.5vw, 0.93rem);
  line-height: 1.55;
  letter-spacing: 0.02em;
  white-space: nowrap;
}

.formula::before {
  position: absolute;
  left: 0.8rem;
  color: var(--table);
  content: "⌁";
}

.end-matter {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(16rem, 0.75fr);
  border-bottom: 1px solid var(--ink);
}

.references,
.end-side {
  padding: clamp(2.2rem, 6vw, 5rem);
}

.references {
  border-right: 1px solid var(--ink);
}

.references h2,
.related h2,
.forthcoming h2 {
  margin: 0 0 1.4rem;
  font-size: 0.78rem;
  font-weight: 750;
  letter-spacing: 0.13em;
  text-transform: uppercase;
}

.references ol {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: refs;
}

.references li {
  position: relative;
  margin: 0 0 1.05rem;
  padding-left: 2.4rem;
  color: var(--ink-soft);
  font-size: 0.9rem;
  line-height: 1.5;
  counter-increment: refs;
}

.references li::before {
  position: absolute;
  left: 0;
  color: var(--signal);
  content: counter(refs, decimal-leading-zero);
  font: 750 0.72rem/1.7 var(--sans);
}

.end-side {
  display: grid;
  align-content: start;
  gap: 3rem;
  background: var(--paper-deep);
}

.related ul,
.forthcoming ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.related li,
.forthcoming li {
  padding: 0.75rem 0;
  border-top: 1px solid var(--line);
  font-size: 0.98rem;
  line-height: 1.4;
}

.status {
  display: block;
  margin-top: 0.25rem;
  color: var(--ink-soft);
  font-size: 0.66rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.article-foot {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.1rem clamp(1.2rem, 5vw, 5rem);
  color: #fff;
  background: var(--ink);
  font-size: 0.73rem;
  line-height: 1.4;
  letter-spacing: 0.05em;
}

.article-foot p {
  margin: 0;
}

@media (max-width: 760px) {
  body {
    background:
      repeating-linear-gradient(0deg, transparent 0 31px, rgba(17, 27, 36, 0.08) 31px 32px),
      var(--table);
  }

  .light-table {
    width: calc(100% - 1rem);
    margin-top: 0.6rem;
    box-shadow: 0.32rem 0.32rem 0 var(--ink);
  }

  .article-head {
    grid-template-columns: 1fr;
    min-height: 0;
  }

  .head-copy {
    min-height: 72vh;
    padding-top: 4rem;
  }

  .head-index {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    border-top: 1px solid var(--ink);
    border-left: 0;
  }

  .head-code {
    grid-template-columns: 1fr;
    gap: 0.35rem;
    border-top: 0;
    border-left: 1px solid var(--ink);
  }

  .head-code:first-child {
    border-left: 0;
  }

  .prelude,
  .chapter {
    grid-template-columns: 1fr;
  }

  .prelude-mark {
    position: static;
    width: 5.7rem;
    height: 5.7rem;
  }

  .chapter-label {
    display: grid;
    grid-template-columns: auto 1fr;
    align-items: center;
    gap: 0.8rem;
  }

  .chapter-code {
    margin: 0;
  }

  .end-matter {
    grid-template-columns: 1fr;
  }

  .references {
    border-right: 0;
    border-bottom: 1px solid var(--ink);
  }

  .article-foot {
    display: block;
  }

  .article-foot p + p {
    margin-top: 0.35rem;
  }
}

@media (max-width: 430px) {
  .site-top {
    padding-inline: 0.65rem;
  }

  h1 {
    font-size: clamp(2.85rem, 16vw, 4.3rem);
  }

  .head-index {
    grid-template-columns: 1fr;
  }

  .head-code {
    grid-template-columns: 2.2rem 1fr;
    border-top: 1px solid var(--ink);
    border-left: 0;
  }

  .prose p,
  .prelude-copy p {
    text-align: left;
    hyphens: none;
  }
}

@media (prefers-contrast: high) {
  :root {
    --ink-soft: #111b24;
    --line: rgba(17, 27, 36, 0.55);
  }

  a {
    text-decoration-thickness: 0.18em;
  }
}

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

@media print {
  html,
  body {
    background: #fff;
  }

  .site-top,
  .skip-link {
    display: none;
  }

  .light-table {
    width: 100%;
    margin: 0;
    border: 0;
    box-shadow: none;
  }

  .chapter,
  .prelude {
    break-inside: avoid;
  }
}