.page-about {
  --ab-rail-w: 236px;
  --ab-cut: 28px;
  background:
    radial-gradient(900px 620px at 84% 4%, rgba(46, 125, 116, .22), transparent 62%),
    linear-gradient(180deg, var(--ink) 0%, var(--indigo) 48%, var(--ink) 100%);
  color: var(--cream);
  overflow-x: clip;
}

.page-about .breadcrumb {
  padding-top: clamp(16px, 2.4vw, 26px);
}

.page-about .ab-hero {
  padding: clamp(18px, 3.6vw, 40px) 0 clamp(34px, 6vw, 78px);
}

.page-about .ab-hero-grid {
  display: grid;
  gap: clamp(26px, 5vw, 56px);
}

.page-about .ab-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(42px, 11vw, 92px);
  line-height: .98;
  letter-spacing: .01em;
  margin: clamp(10px, 1.6vw, 18px) 0 0;
  color: var(--cream);
}

.page-about .ab-lede {
  max-width: 48ch;
  margin: clamp(16px, 2.4vw, 24px) 0 0;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.62;
  color: var(--mist);
}

.page-about .ab-hero-facts {
  list-style: none;
  margin: clamp(20px, 3vw, 30px) 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 14px 28px;
}

.page-about .ab-hero-facts li {
  display: flex;
  flex-direction: column;
  gap: 3px;
  padding-left: 10px;
  border-left: 2px solid var(--jade);
}

.page-about .ab-hero-facts .num {
  font-family: var(--font-mono);
  font-size: clamp(19px, 2.6vw, 25px);
  font-weight: 700;
  color: var(--gold);
  line-height: 1.1;
}

.page-about .ab-fact-label {
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--mist);
}

.page-about .ab-hero-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(22px, 3.4vw, 34px);
}

.page-about .ab-hero-media {
  position: relative;
  margin: 0;
  overflow: hidden;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--ab-cut)), calc(100% - var(--ab-cut)) 100%, 0 100%);
}

.page-about .ab-hero-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 7 / 5;
  object-fit: cover;
}

.page-about .ab-caption {
  position: absolute;
  left: 14px;
  bottom: 12px;
  z-index: 2;
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--cream);
  background: rgba(6, 18, 23, .55);
  padding: 4px 9px;
}

.page-about .ab-body {
  display: grid;
  gap: clamp(26px, 5vw, 60px);
  padding-bottom: clamp(56px, 9vw, 110px);
}

.page-about .ab-rail {
  border-top: 1px solid var(--line-strong);
  padding-top: 14px;
}

.page-about .ab-rail-title {
  margin: 0 0 10px;
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--jade-soft);
}

.page-about .ab-rail-list {
  list-style: none;
  margin: 0 0 24px;
  padding: 0 0 4px;
  display: flex;
  gap: 7px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .ab-rail-link {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  white-space: nowrap;
  padding: 7px 12px;
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--mist);
  text-decoration: none;
  background: rgba(167, 191, 189, .08);
  border-radius: 2px;
  transition: color .2s ease, background .2s ease;
}

.page-about .ab-rail-link .num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--jade-soft);
}

.page-about .ab-rail-link:hover,
.page-about .ab-rail-link:focus-visible {
  color: var(--cream);
  background: var(--jade-veil);
}

.page-about .ab-scale-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.page-about .ab-scale-dot {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .04em;
  color: var(--mist);
  border: 1px solid var(--line);
  padding: 3px 8px;
}

.page-about .ab-scale-dot--live {
  color: var(--ink);
  background: var(--gold);
  border-color: var(--gold);
  font-weight: 700;
}

.page-about .ab-chapter {
  padding: clamp(28px, 4.6vw, 54px) 0;
  border-top: 1px solid var(--line);
  scroll-margin-top: 120px;
}

.page-about .ab-chapter:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .ab-chapter-head {
  display: flex;
  align-items: baseline;
  gap: clamp(10px, 2vw, 18px);
  margin-bottom: clamp(16px, 2.6vw, 26px);
}

.page-about .ab-chapter-no {
  font-family: var(--font-mono);
  font-size: clamp(26px, 5.6vw, 42px);
  font-weight: 700;
  line-height: 1;
  color: var(--jade);
}

.page-about .ab-chapter-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(23px, 4.2vw, 36px);
  line-height: 1.14;
  letter-spacing: .01em;
  color: var(--cream);
}

.page-about .ab-chapter-body p {
  margin: 0 0 1em;
  max-width: 62ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.64;
  color: var(--cream);
}

.page-about .ab-chapter-body p.ab-dim {
  color: var(--mist);
}

.page-about .ab-plate {
  margin: clamp(18px, 3vw, 28px) 0 0;
  padding: clamp(16px, 2.4vw, 24px);
  display: grid;
  gap: 10px;
  background: var(--jade-veil);
  border-left: 3px solid var(--jade);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%);
}

.page-about .ab-plate-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 16px;
  justify-content: space-between;
  align-items: baseline;
  padding-bottom: 9px;
  border-bottom: 1px dashed rgba(167, 191, 189, .18);
}

.page-about .ab-plate-row:last-child {
  padding-bottom: 0;
  border-bottom: 0;
}

.page-about .ab-plate-row dt {
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--jade-soft);
}

.page-about .ab-plate-row dd {
  margin: 0;
  font-size: 14px;
  line-height: 1.5;
  color: var(--cream);
  text-align: right;
}

.page-about .ab-kpis {
  list-style: none;
  margin: clamp(20px, 3vw, 30px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  grid-template-columns: repeat(auto-fit, minmax(148px, 1fr));
  background: var(--line);
}

.page-about .ab-kpi {
  display: flex;
  flex-direction: column;
  gap: 7px;
  padding: clamp(14px, 2vw, 20px);
  background: rgba(15, 42, 58, .92);
}

.page-about .ab-kpi-num {
  font-family: var(--font-mono);
  font-size: clamp(25px, 3.8vw, 33px);
  font-weight: 700;
  line-height: 1;
  color: var(--gold);
}

.page-about .ab-kpi-unit {
  font-size: 13px;
  margin-left: 2px;
  color: var(--jade-soft);
}

.page-about .ab-kpi-label {
  font-size: 12px;
  line-height: 1.45;
  color: var(--mist);
}

.page-about .ab-figure {
  position: relative;
  margin: clamp(20px, 3vw, 30px) 0 0;
  overflow: hidden;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--ab-cut)), calc(100% - var(--ab-cut)) 100%, 0 100%);
}

.page-about .ab-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .ab-tags {
  list-style: none;
  margin: clamp(16px, 2.4vw, 22px) 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .ab-tags .slab {
  font-size: 12px;
  letter-spacing: .04em;
}

.page-about .ab-steps {
  margin: clamp(18px, 3vw, 26px) 0 0;
  border-top: 1px solid var(--line);
}

.page-about .ab-step {
  border-bottom: 1px solid var(--line);
}

.page-about .ab-step summary {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 14px 2px;
  cursor: pointer;
  list-style: none;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: .02em;
  color: var(--cream);
}

.page-about .ab-step summary::-webkit-details-marker {
  display: none;
}

.page-about .ab-step summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--jade-soft);
}

.page-about .ab-step[open] summary::after {
  content: "–";
}

.page-about .ab-step[open] summary {
  color: var(--gold);
}

.page-about .ab-step-no {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--jade);
}

.page-about .ab-step p {
  margin: 0 0 14px;
  padding-left: 30px;
  max-width: 60ch;
  font-size: 14px;
  line-height: 1.62;
  color: var(--mist);
}

.page-about .ab-split {
  margin: clamp(18px, 3vw, 28px) 0 0;
  display: grid;
  gap: 1px;
  background: var(--line-strong);
}

.page-about .ab-cell {
  padding: clamp(16px, 2.4vw, 24px);
  background: rgba(27, 79, 74, .38);
}

.page-about .ab-cell h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 800;
  letter-spacing: .03em;
  color: var(--cream);
}

.page-about .ab-cell p {
  margin: 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--mist);
}

.page-about .ab-cta {
  margin-top: clamp(30px, 5vw, 52px);
  padding: clamp(22px, 4vw, 40px);
  background: linear-gradient(135deg, rgba(46, 125, 116, .30), rgba(15, 42, 58, .94) 68%);
  border-top: 2px solid var(--cinnabar);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 30px), calc(100% - 30px) 100%, 0 100%);
}

.page-about .ab-cta-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(22px, 3.6vw, 30px);
  line-height: 1.16;
  color: var(--cream);
}

.page-about .ab-cta-text {
  margin: 12px 0 0;
  max-width: 54ch;
  font-size: 15px;
  line-height: 1.6;
  color: var(--mist);
}

.page-about .ab-cta-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(18px, 2.6vw, 26px);
}

@media (min-width: 760px) {
  .page-about .ab-hero-grid {
    grid-template-columns: minmax(0, 1.06fr) minmax(0, .94fr);
    align-items: end;
  }

  .page-about .ab-split {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .ab-chapter:nth-child(even) .ab-chapter-body {
    padding-right: clamp(0px, 4vw, 56px);
  }

  .page-about .ab-chapter:nth-child(odd) .ab-chapter-body {
    padding-left: clamp(0px, 3vw, 40px);
    border-left: 1px solid var(--line);
  }
}

@media (min-width: 900px) {
  .page-about .ab-body {
    grid-template-columns: var(--ab-rail-w) minmax(0, 1fr);
    align-items: start;
    gap: clamp(32px, 5vw, 68px);
  }

  .page-about .ab-rail {
    position: sticky;
    top: 96px;
  }

  .page-about .ab-rail-list {
    flex-direction: column;
    gap: 2px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .ab-rail-link {
    display: flex;
    white-space: normal;
    padding: 7px 0 7px 12px;
    background: none;
    border-left: 2px solid var(--line);
    border-radius: 0;
  }

  .page-about .ab-rail-link:hover,
  .page-about .ab-rail-link:focus-visible {
    background: linear-gradient(90deg, var(--jade-veil), transparent 82%);
    border-left-color: var(--jade);
  }

  .page-about .ab-chapter-body p {
    font-size: 17px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-rail-link {
    transition: none;
  }
}
<<<END>>>