.page-about {
  --ab-text: var(--cold-white);
  --ab-muted: var(--index-gray);
  --ab-card: var(--panel-slate);
  --ab-line: var(--hairline);
  --ab-body: rgba(237, 239, 245, .78);
  --ab-gap: 28px;
}

/* 面包屑 */
.page-about .ab-crumb {
  padding: 22px 0 2px;
}
.page-about .ab-crumb .yb-breadcrumb__item {
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--index-gray);
}
.page-about .ab-crumb a.yb-breadcrumb__item {
  color: var(--light-blue);
  text-decoration: none;
}
.page-about .ab-crumb a.yb-breadcrumb__item:hover {
  color: var(--pulse-green);
}
.page-about .ab-crumb__sep {
  margin: 0 8px;
  color: var(--hairline);
}

/* 首屏 */
.page-about .ab-hero {
  position: relative;
  padding: 26px 0 48px;
  border-bottom: 1px solid var(--ab-line);
  overflow: hidden;
  background:
    linear-gradient(180deg, rgba(30, 90, 255, .10), transparent 62%),
    radial-gradient(120% 80% at 88% 0%, rgba(255, 107, 53, .10), transparent 58%);
}
.page-about .ab-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: .5;
  background-image:
    linear-gradient(var(--hairline) 1px, transparent 1px),
    linear-gradient(90deg, var(--hairline) 1px, transparent 1px);
  background-size: 32px 32px;
  -webkit-mask-image: linear-gradient(180deg, #000, transparent 88%);
  mask-image: linear-gradient(180deg, #000, transparent 88%);
}
.page-about .ab-hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  gap: var(--ab-gap);
}
.page-about .ab-hero__eyebrow {
  margin: 0;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .22em;
  color: var(--pulse-green);
}
.page-about .ab-hero__title {
  margin: 12px 0 18px;
  font-family: var(--sans);
  font-weight: 900;
  font-size: clamp(30px, 6.6vw, 60px);
  line-height: 1.08;
  letter-spacing: -.015em;
  color: var(--ab-text);
}
.page-about .ab-hero__lede {
  max-width: 46ch;
  margin: 0;
  font-size: 17px;
  line-height: 1.9;
  color: var(--ab-body);
}
.page-about .ab-hero__figure {
  margin: 4px 0 0;
}
.page-about .ab-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  background: #0E1218;
  border: 1px solid var(--ab-line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
}

/* 首屏数据带 */
.page-about .ab-kpis {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--ab-line);
  border: 1px solid var(--ab-line);
}
.page-about .ab-kpi {
  background: var(--ab-card);
  padding: 14px 16px;
}
.page-about .ab-kpi__num {
  display: block;
  font-family: var(--mono);
  font-size: 24px;
  line-height: 1.2;
  color: var(--ab-text);
  letter-spacing: .01em;
}
.page-about .ab-kpi__num em {
  font-style: normal;
  font-size: 13px;
  color: var(--pulse-green);
}
.page-about .ab-kpi__label {
  display: block;
  margin-top: 6px;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--index-gray);
}

/* 骨架与索引栏 */
.page-about .yb-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  max-width: var(--shell-max);
  margin-inline: auto;
  padding-inline: 20px;
}
.page-about .yb-shell__content {
  min-width: 0;
}
.page-about .yb-rail__item a {
  display: block;
  color: inherit;
  text-decoration: none;
}
.page-about .yb-rail__item a:hover .yb-rail__text,
.page-about .yb-rail__item.is-active .yb-rail__text {
  color: var(--pulse-green);
}

/* 章节通用 */
.page-about .yb-section {
  padding: 52px 0;
  border-bottom: 1px solid var(--ab-line);
}
.page-about .yb-section:last-of-type {
  border-bottom: 0;
  padding-bottom: 72px;
}
.page-about .yb-section__num {
  font-family: var(--serif);
  font-weight: 700;
  color: var(--digital-blue);
  text-shadow: 0 0 34px rgba(30, 90, 255, .45);
}
.page-about .yb-section__title {
  color: var(--ab-text);
}
.page-about .yb-section__excerpt {
  color: var(--ab-body);
}
.page-about .yb-rule {
  margin: 22px 0;
}

/* 01 起点 */
.page-about .ab-origin {
  display: grid;
  gap: 1px;
  background: var(--ab-line);
  border: 1px solid var(--ab-line);
}
.page-about .ab-origin__item {
  background: var(--ab-card);
  padding: 22px 20px;
}
.page-about .ab-origin__k {
  display: inline-block;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--light-blue);
}
.page-about .ab-origin__item h3 {
  margin: 12px 0 10px;
  font-size: 19px;
  font-weight: 800;
  color: var(--ab-text);
}
.page-about .ab-origin__item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.9;
  color: var(--ab-body);
}

/* 02 时间轴 */
.page-about .ab-timeline {
  position: relative;
  list-style: none;
  margin: 34px 0 0;
  padding: 0 0 0 34px;
}
.page-about .ab-timeline::before {
  content: "";
  position: absolute;
  top: 8px;
  bottom: 8px;
  left: 9px;
  width: 1px;
  background: linear-gradient(180deg, var(--digital-blue), var(--hairline) 42%, var(--pulse-green));
}
.page-about .ab-node {
  position: relative;
  margin-bottom: 18px;
}
.page-about .ab-node:last-child {
  margin-bottom: 0;
}
.page-about .ab-node::before {
  content: "";
  position: absolute;
  left: -28px;
  top: 26px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--pulse-green);
  box-shadow: 0 0 0 4px rgba(76, 255, 138, .12);
}
.page-about .ab-node--now::before {
  background: var(--warm-orange);
  box-shadow: 0 0 0 4px rgba(255, 107, 53, .16);
}

.page-about .ab-node__card {
  display: block;
  background: var(--ab-card);
  border: 1px solid var(--ab-line);
  border-left: 3px solid var(--digital-blue);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  transition: border-color .2s ease, background .2s ease;
}
.page-about .ab-node--now .ab-node__card {
  border-left-color: var(--warm-orange);
}
.page-about .ab-node__card[open] {
  border-left-color: var(--pulse-green);
}
.page-about .ab-node__card:hover {
  background: #161C26;
}
.page-about .ab-node__head {
  position: relative;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 4px 14px;
  align-items: baseline;
  padding: 16px 44px 14px 18px;
  cursor: pointer;
  list-style: none;
}
.page-about .ab-node__head::-webkit-details-marker {
  display: none;
}
.page-about .ab-node__head:focus-visible {
  outline: 2px solid var(--light-blue);
  outline-offset: -2px;
}
.page-about .ab-node__head::after {
  content: "+";
  position: absolute;
  right: 16px;
  top: 14px;
  font-family: var(--mono);
  font-size: 17px;
  color: var(--warm-orange);
  transition: transform .2s ease;
}
.page-about .ab-node__card[open] .ab-node__head::after {
  content: "–";
}
.page-about .ab-node__year {
  font-family: var(--serif);
  font-size: 30px;
  font-weight: 700;
  line-height: 1;
  color: var(--screen-white);
}
.page-about .ab-node__title {
  font-size: 16px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--ab-text);
}
.page-about .ab-node__meta {
  grid-column: 1 / -1;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--index-gray);
}
.page-about .ab-node__body {
  padding: 14px 18px 18px;
  margin-top: 0;
  border-top: 1px solid var(--ab-line);
}
.page-about .ab-node__body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.9;
  color: var(--ab-body);
}
.page-about .ab-node__list {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.page-about .ab-node__list li {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--index-gray);
  border: 1px solid var(--ab-line);
  border-radius: var(--radius);
  padding: 4px 9px;
}

/* 03 团队 */
.page-about .ab-team__grid {
  display: grid;
  gap: var(--ab-gap);
  margin-top: 30px;
}
.page-about .ab-team {
  display: grid;
  gap: 1px;
  background: var(--ab-line);
  border: 1px solid var(--ab-line);
}
.page-about .ab-team__item {
  background: var(--ab-card);
  padding: 20px 18px;
}
.page-about .ab-team__name {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 800;
  color: var(--ab-text);
}
.page-about .ab-team__desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.9;
  color: var(--ab-body);
}
.page-about .ab-team__figure {
  margin: 0;
}
.page-about .ab-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  background: #0E1218;
  border: 1px solid var(--ab-line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
}

/* 04 覆盖与规模 */
.page-about .ab-scale {
  display: grid;
  gap: var(--ab-gap);
  margin-top: 30px;
}
.page-about .ab-scale__stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--ab-line);
  border: 1px solid var(--ab-line);
}
.page-about .ab-scale__stats li {
  background: var(--ab-card);
  padding: 18px 16px;
}
.page-about .ab-scale__num {
  display: block;
  font-family: var(--mono);
  font-size: 25px;
  line-height: 1.2;
  letter-spacing: .01em;
  color: var(--ab-text);
}
.page-about .ab-scale__label {
  display: block;
  margin-top: 6px;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--index-gray);
}
.page-about .ab-map {
  border: 1px solid var(--ab-line);
  background: var(--ab-card);
  padding: 22px 20px;
}
.page-about .ab-map__cap {
  margin: 0 0 18px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--index-gray);
}
.page-about .ab-map svg {
  display: block;
  width: 100%;
  height: auto;
  max-width: 420px;
  margin: 0 auto;
}
.page-about .ab-dot {
  fill: #232A36;
}
.page-about .ab-dot.is-on {
  fill: var(--pulse-green);
}

/* 05 更新节奏 */
.page-about .ab-band {
  margin: 30px 0 0;
}
.page-about .ab-band img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  background: #0E1218;
  border: 1px solid var(--ab-line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
}
.page-about .ab-cycle {
  display: grid;
  gap: 18px;
  margin-top: 26px;
}
.page-about .ab-cycle__item {
  background: var(--ab-card);
  border: 1px solid var(--ab-line);
  border-top: 2px solid var(--digital-blue);
  padding: 20px 18px;
}
.page-about .ab-cycle__item:nth-child(2) {
  border-top-color: var(--warm-orange);
}
.page-about .ab-cycle__item:nth-child(3) {
  border-top-color: var(--pulse-green);
}
.page-about .ab-cycle__item h3 {
  margin: 12px 0 8px;
  font-size: 17px;
  font-weight: 800;
  color: var(--ab-text);
}
.page-about .ab-cycle__item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.9;
  color: var(--ab-body);
}

/* 06 案例与互认 */
.page-about .ab-honor {
  display: grid;
  gap: 1px;
  background: var(--ab-line);
  border: 1px solid var(--ab-line);
  margin-top: 30px;
}
.page-about .ab-honor__block {
  background: var(--ab-card);
  padding: 22px 20px;
}
.page-about .ab-honor__k {
  display: inline-block;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--pulse-green);
  border-bottom: 1px solid rgba(76, 255, 138, .35);
  padding-bottom: 3px;
}
.page-about .ab-honor__block h3 {
  margin: 14px 0 10px;
  font-size: 18px;
  font-weight: 800;
  color: var(--ab-text);
}
.page-about .ab-honor__block p {
  margin: 0;
  font-size: 15px;
  line-height: 1.9;
  color: var(--ab-body);
}

/* 07 下一步 */
.page-about .ab-next {
  display: grid;
  gap: 1px;
  background: var(--ab-line);
  border: 1px solid var(--ab-line);
  margin-top: 30px;
}
.page-about .ab-next__card {
  display: block;
  background: var(--ab-card);
  padding: 20px 18px;
  text-decoration: none;
  color: inherit;
  transition: background .2s ease;
}
.page-about .ab-next__card:hover {
  background: #161C26;
}
.page-about .ab-next__card:focus-visible {
  outline: 2px solid var(--light-blue);
  outline-offset: -2px;
}
.page-about .ab-next__title {
  display: block;
  margin: 10px 0 14px;
  font-size: 17px;
  font-weight: 700;
  line-height: 1.6;
  color: var(--ab-text);
}
.page-about .ab-next__arrow {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--warm-orange);
}

/* 平板与桌面 */
@media (min-width: 680px) {
  .page-about .ab-kpis {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .ab-scale__stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .ab-cycle {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .ab-next {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .ab-hero {
    padding: 38px 0 62px;
  }
  .page-about .ab-hero__inner {
    grid-template-columns: minmax(0, 1.28fr) minmax(0, .92fr);
    align-items: start;
    gap: 40px;
  }
  .page-about .ab-hero__figure {
    margin-top: -26px;
  }
  .page-about .ab-origin {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .ab-team {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .ab-honor {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .ab-cycle {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .ab-scale {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
    align-items: start;
  }
}

@media (min-width: 1025px) {
  .page-about .yb-shell {
    grid-template-columns: var(--rail-w) minmax(0, 1fr);
    padding-inline: 24px;
  }
  .page-about .yb-rail {
    position: sticky;
    top: calc(var(--header-h) + 16px);
    align-self: start;
  }
  .page-about .yb-section {
    padding: 64px 0 64px 32px;
  }
  .page-about .yb-section:last-of-type {
    padding-bottom: 88px;
  }
}

/* 桌面：时间轴左右交错，越靠近本季越长 */
@media (min-width: 1080px) {
  .page-about .ab-timeline {
    padding-left: 0;
  }
  .page-about .ab-timeline::before {
    left: 34%;
    top: 14px;
    bottom: 14px;
  }
  .page-about .ab-node {
    margin-bottom: 22px;
    box-sizing: border-box;
  }
  .page-about .ab-node:nth-child(odd) {
    margin-left: 34%;
    padding-left: 30px;
    width: calc(var(--ab-wr) - 30px);
  }
  .page-about .ab-node:nth-child(even) {
    margin-left: calc(34% - var(--ab-wl) - 30px);
    padding-right: 30px;
    width: calc(var(--ab-wl) + 30px);
  }
  .page-about .ab-node:nth-child(odd)::before {
    left: -5px;
  }
  .page-about .ab-node:nth-child(even)::before {
    left: auto;
    right: -5px;
  }
  .page-about .ab-node:nth-child(1) { --ab-wr: 50%; }
  .page-about .ab-node:nth-child(2) { --ab-wl: 26%; }
  .page-about .ab-node:nth-child(3) { --ab-wr: 54%; }
  .page-about .ab-node:nth-child(4) { --ab-wl: 29%; }
  .page-about .ab-node:nth-child(5) { --ab-wr: 58%; }
  .page-about .ab-node:nth-child(6) { --ab-wl: 32%; }
  .page-about .ab-node__head {
    padding: 18px 46px 16px 20px;
  }
  .page-about .ab-node__body {
    padding: 16px 20px 20px;
  }
}

@media (min-width: 1180px) {
  .page-about .ab-team__grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr);
  }
  .page-about .ab-team {
    grid-template-columns: 1.35fr 1fr 1.15fr .85fr;
  }
}

/* 动效 */
@media (prefers-reduced-motion: reduce) {
  .page-about .ab-node__card,
  .page-about .ab-node__head::after,
  .page-about .ab-next__card {
    transition: none;
  }
}