.page-about {
  --ab-r: 14px;
  --ab-line: var(--yx-mist);
  background: var(--yx-paper);
  color: var(--yx-graphite);
}

.page-about .ab-crumb {
  padding-top: clamp(14px, 2vw, 22px);
  padding-bottom: 4px;
  font-size: 13px;
  color: var(--yx-ink-2);
}
.page-about .ab-crumb a {
  color: var(--yx-blue);
  text-decoration: none;
}
.page-about .ab-crumb a:hover,
.page-about .ab-crumb a:focus-visible {
  text-decoration: underline;
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(26px, 4vw, 52px) 0 clamp(32px, 5vw, 60px);
  background:
    radial-gradient(circle at 88% 6%, rgba(212, 160, 23, 0.2), transparent 44%),
    radial-gradient(circle at 4% 96%, rgba(31, 122, 122, 0.12), transparent 42%),
    linear-gradient(165deg, var(--yx-ice) 0%, var(--yx-paper) 62%);
}
.page-about .ab-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(45deg, rgba(10, 76, 140, 0.07) 0 1px, transparent 1px 20px),
    repeating-linear-gradient(-45deg, rgba(10, 76, 140, 0.07) 0 1px, transparent 1px 20px);
  -webkit-mask-image: radial-gradient(circle at 80% 24%, #000 0%, transparent 64%);
  mask-image: radial-gradient(circle at 80% 24%, #000 0%, transparent 64%);
}
.page-about .ab-hero__inner {
  position: relative;
  display: grid;
  gap: clamp(24px, 4vw, 48px);
  align-items: center;
}
.page-about .ab-hero h1 {
  margin: 10px 0 0;
  font-size: clamp(34px, 7vw, 56px);
  line-height: 1.12;
  letter-spacing: -0.02em;
  font-weight: 800;
  color: var(--yx-deep);
}
.page-about .ab-hl {
  background: linear-gradient(var(--yx-gold-soft), var(--yx-gold-soft)) no-repeat left 88% / 100% 0.3em;
  padding: 0 2px;
}
.page-about .ab-hero__text .yx-lede {
  margin-top: 16px;
  max-width: 60ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--yx-ink-2);
}
.page-about .ab-hero__facts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(112px, 1fr));
  gap: 16px 18px;
  margin-top: 26px;
  padding-top: 18px;
  border-top: 1px solid rgba(10, 76, 140, 0.16);
}
.page-about .ab-fact__num {
  display: block;
  font-family: var(--yx-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(21px, 3.4vw, 27px);
  font-weight: 700;
  line-height: 1.15;
  color: var(--yx-blue);
  letter-spacing: -0.01em;
}
.page-about .ab-fact__lbl {
  display: block;
  margin-top: 5px;
  font-size: 12.5px;
  line-height: 1.5;
  color: var(--yx-ink-2);
}
.page-about .ab-hero__media {
  margin: 0;
  border-radius: var(--ab-r);
  overflow: hidden;
  border: 1px solid rgba(10, 76, 140, 0.14);
  box-shadow: var(--yx-shadow-2);
  background: var(--yx-paper);
}
.page-about .ab-hero__media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 主体两栏 ---------- */
.page-about .ab-layout {
  display: grid;
  gap: 0;
  padding-bottom: clamp(40px, 7vw, 88px);
}

.page-about .ab-side {
  position: relative;
}
.page-about .ab-side__label {
  margin: 0 0 4px;
  font-family: var(--yx-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--yx-ink-2);
}
.page-about .ab-toc {
  position: relative;
  counter-reset: ab-c;
  list-style: none;
  margin: 0;
  padding: 10px 0;
  display: flex;
  gap: 6px;
  overflow-x: auto;
  border-bottom: 1px solid var(--ab-line);
  scrollbar-width: none;
}
.page-about .ab-toc::-webkit-scrollbar {
  display: none;
}
.page-about .ab-toc li {
  flex: 0 0 auto;
}
.page-about .ab-toc a {
  display: flex;
  align-items: baseline;
  gap: 7px;
  padding: 8px 12px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-size: 13.5px;
  line-height: 1.4;
  color: var(--yx-ink-2);
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.18s var(--yx-ease), background 0.18s var(--yx-ease), border-color 0.18s var(--yx-ease);
}
.page-about .ab-toc a::before {
  counter-increment: ab-c;
  content: counter(ab-c, decimal-leading-zero);
  font-family: var(--yx-mono);
  font-size: 11px;
  color: var(--yx-gold);
  letter-spacing: 0.04em;
}
.page-about .ab-toc a:hover {
  color: var(--yx-blue);
  background: var(--yx-ice);
  border-color: var(--ab-line);
}
.page-about .ab-toc a:focus-visible {
  outline: 2px solid var(--yx-coral);
  outline-offset: 2px;
  color: var(--yx-blue);
}

/* ---------- 章节 ---------- */
.page-about .ab-sec {
  padding: clamp(28px, 4.6vw, 52px) 0;
  border-top: 1px solid var(--ab-line);
}
.page-about .ab-sec:first-child {
  border-top: 0;
  padding-top: clamp(24px, 3.6vw, 40px);
}
.page-about .ab-sec__title {
  margin: 0 0 14px;
  scroll-margin-top: 100px;
  font-size: clamp(23px, 4vw, 33px);
  line-height: 1.26;
  letter-spacing: -0.01em;
  font-weight: 800;
  color: var(--yx-deep);
}
.page-about .ab-sec__no {
  display: inline-block;
  margin-right: 10px;
  padding: 2px 7px;
  border-radius: 3px;
  background: var(--yx-gold-soft);
  font-family: var(--yx-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--yx-deep);
  vertical-align: 6px;
  letter-spacing: 0.04em;
}
.page-about .ab-body p {
  margin: 0 0 15px;
  max-width: 66ch;
  font-size: 16px;
  line-height: 1.88;
  color: var(--yx-graphite);
}
.page-about .ab-body p:last-child {
  margin-bottom: 0;
}
.page-about .ab-body__lead {
  margin: 0;
  max-width: 64ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--yx-ink-2);
}
.page-about .ab-note {
  margin: 20px 0 0;
  max-width: 60ch;
  padding: 13px 16px;
  border-left: 3px solid var(--yx-gold);
  border-radius: 0 6px 6px 0;
  background: var(--yx-gold-soft);
  font-size: 14px;
  line-height: 1.75;
  color: var(--yx-deep);
}

/* ---------- 时间线 ---------- */
.page-about .ab-tl {
  position: relative;
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
}
.page-about .ab-tl::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 6px;
  bottom: 6px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(var(--yx-blue), var(--yx-gold) 62%, var(--ab-line));
}
.page-about .ab-tl__item {
  position: relative;
  padding: 0 0 26px 40px;
}
.page-about .ab-tl__item::before {
  content: "";
  position: absolute;
  left: 3px;
  top: 5px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--yx-paper);
  border: 3px solid var(--yx-blue);
}
.page-about .ab-tl__item:last-child {
  padding-bottom: 0;
}
.page-about .ab-tl__item:last-child::before {
  border-color: var(--yx-gold);
  box-shadow: 0 0 0 4px rgba(212, 160, 23, 0.16);
}
.page-about .ab-tl__year {
  display: inline-block;
  margin-bottom: 8px;
  padding: 2px 8px;
  border-radius: 3px;
  background: var(--yx-ice);
  font-family: var(--yx-mono);
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: var(--yx-blue);
}
.page-about .ab-tl__title {
  margin: 0 0 6px;
  font-size: 17px;
  line-height: 1.45;
  font-weight: 700;
  color: var(--yx-deep);
}
.page-about .ab-tl__text {
  margin: 0;
  max-width: 48ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--yx-ink-2);
}

/* ---------- 图片组件 ---------- */
.page-about .ab-media {
  margin: 26px 0 0;
  border-radius: var(--ab-r);
  overflow: hidden;
  border: 1px solid var(--ab-line);
  background: var(--yx-ice);
}
.page-about .ab-media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .ab-media__cap {
  padding: 10px 14px;
  border-top: 1px solid var(--ab-line);
  background: var(--yx-paper);
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--yx-ink-2);
}

/* ---------- 团队 ---------- */
.page-about .ab-team {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin-top: 24px;
}
.page-about .ab-team__card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 20px;
  border: 1px solid var(--ab-line);
  border-radius: var(--ab-r);
  background: var(--yx-paper);
  box-shadow: var(--yx-shadow-1);
  transition: transform 0.2s var(--yx-ease), border-color 0.2s var(--yx-ease), box-shadow 0.2s var(--yx-ease);
}
.page-about .ab-team__card--wide {
  background: linear-gradient(170deg, #ffffff 0%, var(--yx-ice) 100%);
}
.page-about .ab-team__card:hover,
.page-about .ab-team__card:focus-within {
  transform: translateY(-3px);
  border-color: var(--yx-gold);
  box-shadow: var(--yx-shadow-2);
}
.page-about .ab-team__card .yx-tag {
  align-self: flex-start;
}
.page-about .ab-team__name {
  margin: 0;
  font-size: 17px;
  line-height: 1.45;
  font-weight: 700;
  color: var(--yx-deep);
}
.page-about .ab-team__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--yx-ink-2);
}
.page-about .ab-team__link {
  margin-top: auto;
  padding-top: 6px;
  align-self: flex-start;
  font-size: 13.5px;
  font-weight: 700;
  color: var(--yx-blue);
  text-decoration: none;
  border-bottom: 2px solid var(--yx-gold-soft);
}
.page-about .ab-team__link:hover {
  border-bottom-color: var(--yx-gold);
}
.page-about .ab-team__link:focus-visible {
  outline: 2px solid var(--yx-coral);
  outline-offset: 3px;
}

/* ---------- 体系徽章 ---------- */
.page-about .ab-badges {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(146px, 1fr));
  gap: 12px;
  margin-top: 24px;
}
.page-about .ab-badge {
  padding: 14px 15px;
  border: 1px solid var(--ab-line);
  border-top: 3px solid var(--yx-blue);
  border-radius: 6px;
  background: linear-gradient(180deg, #ffffff 0%, var(--yx-ice) 100%);
}
.page-about .ab-badge:nth-child(2n) {
  border-top-color: var(--yx-teal);
}
.page-about .ab-badge:nth-child(3n) {
  border-top-color: var(--yx-gold);
}
.page-about .ab-badge__k {
  display: block;
  font-family: var(--yx-mono);
  font-variant-numeric: tabular-nums;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--yx-deep);
}
.page-about .ab-badge__v {
  display: block;
  margin-top: 5px;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--yx-ink-2);
}

/* ---------- 合作生态 ---------- */
.page-about .ab-eco {
  position: relative;
  overflow: hidden;
  margin-top: 20px;
  padding: clamp(22px, 3.6vw, 38px);
  border-radius: var(--ab-r);
  background:
    radial-gradient(circle at 88% 10%, rgba(212, 160, 23, 0.24), transparent 46%),
    var(--yx-deep);
  color: var(--yx-ice);
}
.page-about .ab-eco::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(45deg, rgba(234, 242, 250, 0.08) 0 1px, transparent 1px 22px);
  -webkit-mask-image: linear-gradient(120deg, transparent 30%, #000 100%);
  mask-image: linear-gradient(120deg, transparent 30%, #000 100%);
}
.page-about .ab-eco__stats {
  position: relative;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 16px 18px;
  padding-bottom: 18px;
  border-bottom: 1px solid rgba(234, 242, 250, 0.24);
}
.page-about .ab-eco__num {
  display: block;
  font-family: var(--yx-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(24px, 4vw, 32px);
  font-weight: 700;
  line-height: 1.1;
  color: var(--yx-gold);
}
.page-about .ab-eco__lbl {
  display: block;
  margin-top: 5px;
  font-size: 12.5px;
  line-height: 1.5;
  color: rgba(234, 242, 250, 0.78);
}
.page-about .ab-eco__text {
  position: relative;
  margin: 18px 0 0;
  max-width: 68ch;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(234, 242, 250, 0.86);
}
.page-about .ab-eco__honor {
  position: relative;
  margin: 20px 0 0;
  padding-top: 16px;
  border-top: 1px solid rgba(234, 242, 250, 0.2);
  max-width: 68ch;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(234, 242, 250, 0.9);
}
.page-about .ab-eco__honor .yx-tag {
  margin-right: 8px;
}

/* ---------- 起步入口 ---------- */
.page-about .ab-start {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin-top: 24px;
}
.page-about .ab-start__card {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 20px;
  border: 1px solid var(--ab-line);
  border-radius: var(--ab-r);
  background: var(--yx-paper);
  text-decoration: none;
  color: inherit;
  transition: transform 0.2s var(--yx-ease), border-color 0.2s var(--yx-ease), box-shadow 0.2s var(--yx-ease);
}
.page-about .ab-start__card:hover {
  transform: translateY(-3px);
  border-color: var(--yx-blue);
  box-shadow: var(--yx-shadow-2);
}
.page-about .ab-start__card:focus-visible {
  outline: 2px solid var(--yx-coral);
  outline-offset: 3px;
}
.page-about .ab-start__idx {
  font-family: var(--yx-mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: var(--yx-gold);
}
.page-about .ab-start__name {
  margin: 0;
  font-size: 17px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--yx-deep);
}
.page-about .ab-start__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--yx-ink-2);
}
.page-about .ab-start__go {
  margin-top: 8px;
  font-size: 13.5px;
  font-weight: 700;
  color: var(--yx-blue);
}
.page-about .ab-start__card--accent {
  border-color: rgba(232, 93, 74, 0.42);
  background: linear-gradient(170deg, #ffffff 0%, #fdf1ef 100%);
}
.page-about .ab-start__card--accent .ab-start__go {
  color: var(--yx-coral);
}

/* ---------- 联系条 ---------- */
.page-about .ab-contactline {
  margin-top: 24px;
  padding: 18px 20px;
  border: 1px solid var(--ab-line);
  border-left: 4px solid var(--yx-blue);
  border-radius: 0 var(--ab-r) var(--ab-r) 0;
  background: var(--yx-ice);
}
.page-about .ab-contactline__row {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 14px;
  margin: 0 0 10px;
  font-size: 14px;
  line-height: 1.7;
}
.page-about .ab-contactline__row:last-child {
  margin-bottom: 0;
}
.page-about .ab-contactline__k {
  flex: 0 0 76px;
  color: var(--yx-ink-2);
}
.page-about .ab-contactline__v {
  color: var(--yx-deep);
  font-weight: 600;
}
.page-about .ab-top {
  display: inline-block;
  margin-top: 22px;
  font-size: 13px;
  font-weight: 700;
  color: var(--yx-blue);
  text-decoration: none;
  border-bottom: 2px solid var(--yx-gold-soft);
}
.page-about .ab-top:hover {
  border-bottom-color: var(--yx-gold);
}
.page-about .ab-top:focus-visible {
  outline: 2px solid var(--yx-coral);
  outline-offset: 3px;
}

/* ---------- 断点 ---------- */
@media (min-width: 620px) {
  .page-about .ab-team {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .ab-start {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .ab-hero__inner {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  }
  .page-about .ab-tl::before {
    left: 50%;
    transform: translateX(-1px);
  }
  .page-about .ab-tl__item {
    width: 50%;
    padding: 0 42px 34px 0;
  }
  .page-about .ab-tl__item:nth-child(even) {
    margin-left: 50%;
    padding: 0 0 34px 42px;
  }
  .page-about .ab-tl__item:nth-child(3n + 2) {
    margin-top: 16px;
  }
  .page-about .ab-tl__item::before {
    left: auto;
    right: -8px;
  }
  .page-about .ab-tl__item:nth-child(even)::before {
    right: auto;
    left: -8px;
  }
  .page-about .ab-tl__text {
    max-width: none;
  }
}

@media (min-width: 1024px) {
  .page-about .ab-layout {
    grid-template-columns: 210px minmax(0, 1fr);
    gap: clamp(30px, 4vw, 62px);
    align-items: start;
  }
  .page-about .ab-side {
    position: sticky;
    top: 96px;
    align-self: start;
  }
  .page-about .ab-toc {
    flex-direction: column;
    gap: 2px;
    overflow: visible;
    padding: 4px 0 4px 14px;
    border-bottom: 0;
    border-left: 1px solid var(--ab-line);
  }
  .page-about .ab-toc::before {
    content: "";
    position: absolute;
    left: -1px;
    top: 0;
    width: 2px;
    height: 58%;
    border-radius: 2px;
    background: linear-gradient(var(--yx-gold), rgba(212, 160, 23, 0));
  }
  .page-about .ab-toc li {
    flex: 0 1 auto;
  }
  .page-about .ab-toc a {
    border-radius: 4px;
    padding: 7px 10px;
    white-space: normal;
    line-height: 1.5;
  }
  .page-about .ab-team {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }
  .page-about .ab-team > :nth-child(1) {
    grid-column: span 4;
  }
  .page-about .ab-team > :nth-child(2) {
    grid-column: span 2;
  }
  .page-about .ab-team > :nth-child(3) {
    grid-column: span 2;
  }
  .page-about .ab-team > :nth-child(4) {
    grid-column: span 4;
  }
  .page-about .ab-start {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-team__card,
  .page-about .ab-start__card,
  .page-about .ab-toc a {
    transition: none;
  }
  .page-about .ab-team__card:hover,
  .page-about .ab-team__card:focus-within,
  .page-about .ab-start__card:hover {
    transform: none;
  }
}

@media print {
  .page-about .ab-side,
  .page-about .ab-top {
    display: none;
  }
  .page-about .ab-hero {
    background: none;
    padding-top: 0;
  }
  .page-about .ab-hero::before,
  .page-about .ab-eco::after {
    display: none;
  }
  .page-about .ab-sec {
    break-inside: avoid;
  }
}
<<<END>>>