.page-about {
  background: var(--ink-900);
  color: var(--silver);
}

/* ---------- Hero ---------- */
.page-about .ab-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  border-bottom: 1px solid rgba(126, 143, 136, 0.22);
}

.page-about .ab-hero__media {
  position: absolute;
  inset: 0;
  z-index: -2;
}

.page-about .ab-hero__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.38;
  filter: saturate(0.75) contrast(1.08);
}

.page-about .ab-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(120% 90% at 12% 6%, rgba(45, 240, 198, 0.16), transparent 58%),
    linear-gradient(180deg, rgba(5, 16, 12, 0.5) 0%, rgba(5, 16, 12, 0.94) 82%);
}

.page-about .ab-hero__inner {
  padding-block: 72px 40px;
}

.page-about .ab-hero__crumbs {
  margin-bottom: 28px;
}

.page-about .ab-hero__title {
  margin: 14px 0 18px;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: clamp(2rem, 8vw, 3.5rem);
  line-height: 1.08;
  letter-spacing: -0.02em;
  color: var(--paper);
  max-width: 18ch;
}

.page-about .ab-hero__lead {
  max-width: 56ch;
  font-size: 16px;
  line-height: 1.75;
  color: var(--silver);
}

.page-about .ab-hero__facts {
  list-style: none;
  margin: 36px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: rgba(126, 143, 136, 0.22);
  border: 1px solid rgba(126, 143, 136, 0.22);
  border-radius: var(--r-card);
  overflow: hidden;
}

.page-about .ab-hero__facts li {
  background: var(--ink-800);
  padding: 16px 18px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .ab-hero__facts .yb-num {
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 700;
  color: var(--signal);
  letter-spacing: -0.01em;
}

.page-about .ab-hero__factkey {
  font-size: 12px;
  color: var(--line);
  letter-spacing: 0.04em;
}

/* ---------- Body shell ---------- */
.page-about .ab-body {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  padding-bottom: 8px;
}

/* ---------- Vertical index ---------- */
.page-about .ab-index {
  position: sticky;
  top: 0;
  z-index: 3;
  background: rgba(5, 16, 12, 0.94);
  border-bottom: 1px solid rgba(126, 143, 136, 0.22);
  margin-inline: -20px;
  padding-inline: 20px;
}

.page-about .ab-index__list {
  list-style: none;
  margin: 0;
  padding: 10px 0;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  scrollbar-width: none;
}

.page-about .ab-index__list::-webkit-scrollbar {
  display: none;
}

.page-about .ab-index__item {
  flex: 0 0 auto;
}

.page-about .ab-index__link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 12px;
  border: 1px solid rgba(126, 143, 136, 0.28);
  border-radius: var(--r-pill);
  font-size: 13px;
  color: var(--silver);
  text-decoration: none;
  white-space: nowrap;
  background: var(--ink-800);
  transition: border-color 180ms var(--ease), color 180ms var(--ease), background 180ms var(--ease);
}

.page-about .ab-index__link:hover,
.page-about .ab-index__link:focus-visible {
  border-color: var(--signal);
  color: var(--paper);
  background: var(--ink-700);
}

.page-about .ab-index__link:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: 2px;
}

.page-about .ab-index__num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--signal-deep);
}

/* ---------- Chapters ---------- */
.page-about .ab-chapter {
  padding-block: 52px;
  border-bottom: 1px solid rgba(126, 143, 136, 0.16);
  scroll-margin-top: 76px;
}

.page-about .ab-chapter--last {
  border-bottom: 0;
}

.page-about .ab-chapter__head {
  margin-bottom: 28px;
}

.page-about .ab-chapter__head .yb-title {
  margin: 10px 0 0;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: clamp(1.4rem, 5.2vw, 2rem);
  line-height: 1.22;
  letter-spacing: -0.02em;
  color: var(--paper);
  max-width: 26ch;
}

.page-about .ab-chapter__note {
  margin: 12px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--line);
  max-width: 48ch;
}

/* ---------- Origin ---------- */
.page-about .ab-origin {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

.page-about .ab-origin__text p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.78;
  color: var(--silver);
}

.page-about .ab-origin__text p:last-child {
  margin-bottom: 0;
}

.page-about .ab-pull {
  margin: 0;
  padding: 22px 20px;
  background: var(--ink-800);
  border-left: 3px solid var(--signal);
  border-radius: 0 var(--r-card) var(--r-card) 0;
}

.page-about .ab-pull p {
  margin: 0 0 12px;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: 19px;
  line-height: 1.62;
  color: var(--paper);
}

.page-about .ab-pull footer {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--line);
}

/* ---------- Timeline ---------- */
.page-about .ab-timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 6px;
}

.page-about .ab-node {
  position: relative;
  padding: 18px 18px 16px;
  background: var(--ink-800);
  border: 1px solid rgba(126, 143, 136, 0.2);
  border-radius: var(--r-card);
  transition: border-color 180ms var(--ease), background 180ms var(--ease), transform 180ms var(--ease);
}

.page-about .ab-node:hover,
.page-about .ab-node:focus-within {
  border-color: rgba(45, 240, 198, 0.55);
  background: var(--ink-700);
  transform: translateX(3px);
}

.page-about .ab-node__meta {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 6px;
}

.page-about .ab-node__meta .yb-num {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--signal);
  letter-spacing: 0.02em;
}

.page-about .ab-node__title {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 700;
  color: var(--paper);
  letter-spacing: -0.01em;
}

.page-about .ab-node__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--silver);
}

.page-about .ab-node__more {
  margin: 0;
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  font-size: 13px;
  line-height: 1.65;
  color: var(--line);
  transition: max-height 200ms var(--ease), opacity 180ms var(--ease), margin 200ms var(--ease);
}

.page-about .ab-node:hover .ab-node__more,
.page-about .ab-node:focus-within .ab-node__more {
  max-height: 80px;
  opacity: 1;
  margin-top: 8px;
}

.page-about .ab-node__bar {
  margin-top: 14px;
  height: 3px;
  border-radius: 999px;
  background: rgba(126, 143, 136, 0.24);
  overflow: hidden;
}

.page-about .ab-node__bar span {
  display: block;
  height: 100%;
  background: linear-gradient(90deg, var(--signal-deep), var(--signal));
  border-radius: 999px;
}

.page-about .ab-node--now {
  background:
    linear-gradient(120deg, rgba(45, 240, 198, 0.1), transparent 62%),
    var(--ink-700);
  border-color: rgba(45, 240, 198, 0.4);
}

.page-about .ab-node--now .ab-node__bar span {
  background: linear-gradient(90deg, var(--warm), var(--signal));
}

/* ---------- Team ---------- */
.page-about .ab-team {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

.page-about .ab-team__left {
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
}

.page-about .ab-team__chart {
  padding: 18px;
  background: var(--ink-800);
  border: 1px solid rgba(126, 143, 136, 0.22);
  border-radius: var(--r-card);
  display: flex;
  justify-content: center;
}

.page-about .ab-donut {
  width: 100%;
  max-width: 230px;
  height: auto;
  transform: rotate(-90deg);
}

.page-about .ab-donut__seg {
  fill: none;
  stroke-width: 26;
  transition: stroke-width 180ms var(--ease), opacity 180ms var(--ease);
}

.page-about .ab-donut__seg:hover {
  stroke-width: 34;
}

.page-about .ab-donut__seg--a {
  stroke: var(--signal);
}

.page-about .ab-donut__seg--b {
  stroke: var(--signal-deep);
}

.page-about .ab-donut__seg--c {
  stroke: var(--warm);
}

.page-about .ab-donut__seg--d {
  stroke: var(--line);
}

.page-about .ab-donut__num {
  transform: rotate(90deg);
  transform-origin: 100px 100px;
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  fill: var(--paper);
}

.page-about .ab-donut__cap {
  transform: rotate(90deg);
  transform-origin: 100px 100px;
  font-family: var(--font-sans);
  font-size: 9px;
  letter-spacing: 0.08em;
  fill: var(--line);
}

.page-about .ab-legend {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: rgba(126, 143, 136, 0.2);
  border: 1px solid rgba(126, 143, 136, 0.2);
  border-radius: var(--r-card);
  overflow: hidden;
}

.page-about .ab-legend__item {
  display: grid;
  grid-template-columns: auto 1fr auto;
  grid-template-areas: "dot name val" "desc desc desc";
  align-items: center;
  gap: 4px 8px;
  padding: 12px 14px;
  background: var(--ink-800);
}

.page-about .ab-legend__dot {
  grid-area: dot;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--line);
}

.page-about .ab-legend__item--a .ab-legend__dot {
  background: var(--signal);
}

.page-about .ab-legend__item--b .ab-legend__dot {
  background: var(--signal-deep);
}

.page-about .ab-legend__item--c .ab-legend__dot {
  background: var(--warm);
}

.page-about .ab-legend__name {
  grid-area: name;
  font-size: 14px;
  color: var(--paper);
}

.page-about .ab-legend__val {
  grid-area: val;
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .ab-legend__desc {
  grid-area: desc;
  font-size: 12px;
  line-height: 1.6;
  color: var(--line);
}

/* ---------- Figures ---------- */
.page-about .ab-figure {
  margin: 0;
  border: 1px solid rgba(126, 143, 136, 0.22);
  border-radius: var(--r-card);
  overflow: hidden;
  background: var(--ink-800);
}

.page-about .ab-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  opacity: 0.82;
}

.page-about .ab-figure figcaption {
  padding: 12px 16px 14px;
  font-size: 12px;
  line-height: 1.7;
  color: var(--line);
  border-top: 1px solid rgba(126, 143, 136, 0.18);
}

/* ---------- Review flow ---------- */
.page-about .ab-flow {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .ab-flow__step {
  position: relative;
  padding: 20px 18px;
  background: var(--ink-800);
  border: 1px solid rgba(126, 143, 136, 0.22);
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 0 100%);
  transition: border-color 180ms var(--ease), background 180ms var(--ease);
}

.page-about .ab-flow__step:hover {
  border-color: rgba(45, 240, 198, 0.5);
  background: var(--ink-700);
}

.page-about .ab-flow__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--warm);
  letter-spacing: 0.08em;
  margin-bottom: 8px;
}

.page-about .ab-flow__title {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .ab-flow__step p {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: var(--silver);
}

.page-about .ab-review__strip {
  display: grid;
  gap: 1px;
  background: rgba(126, 143, 136, 0.2);
  border: 1px solid rgba(126, 143, 136, 0.2);
  border-radius: var(--r-card);
  overflow: hidden;
  padding: 0;
}

.page-about .ab-review__strip .yb-kv {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  padding: 12px 16px;
  background: var(--ink-800);
  font-size: 13px;
}

.page-about .ab-review__strip .yb-kv__key {
  color: var(--line);
}

.page-about .ab-review__strip .yb-kv__val {
  font-family: var(--font-mono);
  color: var(--paper);
}

.page-about .ab-review__strip .yb-link {
  display: block;
  padding: 13px 16px;
  background: var(--ink-700);
  font-size: 13px;
}

/* ---------- Scale bento ---------- */
.page-about .ab-scale {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.page-about .ab-stat {
  padding: 18px 16px;
  background: var(--ink-800);
  border: 1px solid rgba(126, 143, 136, 0.2);
  border-radius: var(--r-card);
  transition: border-color 180ms var(--ease), background 180ms var(--ease);
}

.page-about .ab-stat:hover {
  border-color: rgba(45, 240, 198, 0.45);
  background: var(--ink-700);
}

.page-about .ab-stat--wide {
  grid-column: span 2;
}

.page-about .ab-stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  line-height: 1.1;
  color: var(--signal);
  letter-spacing: -0.01em;
}

.page-about .ab-stat__key {
  display: block;
  margin-top: 4px;
  font-size: 13px;
  color: var(--paper);
}

.page-about .ab-stat__desc {
  margin: 8px 0 0;
  font-size: 12px;
  line-height: 1.7;
  color: var(--line);
}

.page-about .ab-stat--accent {
  background:
    linear-gradient(110deg, rgba(255, 122, 51, 0.14), transparent 60%),
    var(--ink-700);
  border-color: rgba(255, 122, 51, 0.35);
}

.page-about .ab-stat--accent .ab-stat__num {
  color: var(--warm);
}

.page-about .ab-scale__fig {
  grid-column: span 2;
}

.page-about .ab-scale__fig img {
  aspect-ratio: 1 / 1;
}

.page-about .ab-scale__links {
  margin: 20px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--line);
}

/* ---------- CTA ---------- */
.page-about .ab-cta {
  display: grid;
  grid-template-columns: 1fr;
  gap: 22px;
  padding: 26px 20px;
  background:
    radial-gradient(90% 120% at 0% 0%, rgba(45, 240, 198, 0.12), transparent 60%),
    var(--ink-800);
  border: 1px solid rgba(126, 143, 136, 0.24);
  border-radius: var(--r-card);
}

.page-about .ab-cta__body p {
  margin: 10px 0 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--silver);
  max-width: 52ch;
}

.page-about .ab-cta__actions {
  margin-top: 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .ab-cta__meta {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: rgba(126, 143, 136, 0.2);
  border: 1px solid rgba(126, 143, 136, 0.2);
  border-radius: var(--r-card);
  overflow: hidden;
}

.page-about .ab-cta__meta li {
  background: var(--ink-900);
  padding: 12px 14px;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.page-about .ab-cta__key {
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--line);
}

.page-about .ab-cta__val {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--paper);
  word-break: break-word;
}

/* ---------- Responsive ---------- */
@media (min-width: 720px) {
  .page-about .ab-hero__inner {
    padding-block: 96px 56px;
  }

  .page-about .ab-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .ab-origin {
    grid-template-columns: minmax(0, 1.55fr) minmax(0, 1fr);
    gap: 32px;
    align-items: start;
  }

  .page-about .ab-flow {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .ab-scale {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .ab-stat__num {
    font-size: 34px;
  }
}

@media (min-width: 960px) {
  .page-about .ab-body {
    grid-template-columns: 164px minmax(0, 1fr);
    gap: 48px;
    align-items: start;
    padding-top: 8px;
  }

  .page-about .ab-index {
    position: sticky;
    top: 92px;
    margin-inline: 0;
    padding-inline: 0;
    background: transparent;
    border-bottom: 0;
    border-left: 1px solid rgba(126, 143, 136, 0.22);
  }

  .page-about .ab-index__list {
    flex-direction: column;
    gap: 2px;
    padding: 4px 0 4px 14px;
    overflow: visible;
  }

  .page-about .ab-index__link {
    border-radius: 0;
    border: 0;
    background: transparent;
    padding: 9px 0;
    font-size: 13px;
    color: var(--line);
  }

  .page-about .ab-index__link:hover,
  .page-about .ab-index__link:focus-visible {
    color: var(--paper);
    background: transparent;
    transform: translateX(3px);
  }

  .page-about .ab-index__link:hover .ab-index__num,
  .page-about .ab-index__link:focus-visible .ab-index__num {
    color: var(--signal);
  }

  .page-about .ab-chapter {
    padding-block: 72px;
    scroll-margin-top: 100px;
  }

  .page-about .ab-team {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.92fr);
    gap: 32px;
    align-items: start;
  }

  .page-about .ab-scale__fig {
    grid-column: span 2;
    grid-row: span 1;
  }

  .page-about .ab-cta {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
    gap: 36px;
    padding: 40px 36px;
    align-items: start;
  }

  .page-about .ab-node {
    padding: 20px 24px 18px;
  }

  .page-about .ab-node__title {
    font-size: 18px;
  }
}