.page-about {
  --ab-cyan: var(--cyan-400);
  --ab-orange: var(--orange-500);
  --ab-track: rgba(51, 69, 111, 0.6);
  position: relative;
  background: var(--ink-900);
  color: var(--white-050);
  overflow-x: clip;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  padding-top: 22px;
  padding-bottom: 4px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--violet-400);
}
.page-about .breadcrumbs a {
  color: var(--steel-300);
  text-decoration: none;
  transition: color 180ms var(--ease);
}
.page-about .breadcrumbs a:hover { color: var(--ab-cyan); }
.page-about .breadcrumbs .crumb-sep { color: var(--line-600); }

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding-top: 26px;
  padding-bottom: 46px;
}
.page-about .about-hero__grid {
  display: grid;
  gap: 34px;
}
@media (min-width: 960px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: 56px;
    align-items: end;
  }
}
.page-about .about-hero__title {
  margin: 16px 0 0;
  font-family: var(--font-display);
  font-size: clamp(34px, 7.2vw, 68px);
  font-weight: 900;
  line-height: 1.02;
  letter-spacing: -0.03em;
  color: var(--white-050);
}
.page-about .about-hero__lede {
  margin-top: 22px;
  max-width: 58ch;
  font-size: 17px;
  line-height: 1.75;
  color: var(--steel-300);
}

/* ---------- 首屏章节索引 ---------- */
.page-about .about-index {
  display: grid;
  gap: 0;
  border-top: 1px solid var(--line-600);
}
.page-about .about-index__item {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 12px 8px 12px 0;
  border-bottom: 1px solid rgba(51, 69, 111, 0.55);
  color: var(--steel-300);
  text-decoration: none;
  font-size: 15px;
  line-height: 1.4;
  transition: color 180ms var(--ease), padding-left 180ms var(--ease);
}
.page-about .about-index__item:hover,
.page-about .about-index__item:focus-visible {
  color: var(--ab-cyan);
  padding-left: 10px;
}
.page-about .about-index__no {
  font-size: 12px;
  color: var(--violet-400);
  flex: 0 0 auto;
}
.page-about .about-index__item:hover .about-index__no { color: var(--ab-cyan); }

/* ---------- 通用区块 ---------- */
.page-about .ab-sec {
  position: relative;
  padding: 62px 0;
}
.page-about .ab-sec--tight { padding: 40px 0 26px; }
.page-about .ab-sec--panel {
  background: var(--ink-800);
  border-top: 1px solid rgba(51, 69, 111, 0.4);
  border-bottom: 1px solid rgba(51, 69, 111, 0.4);
}
.page-about .ab-sec__head {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 12px 16px;
  margin-bottom: 22px;
}
.page-about .ab-sec__head::after {
  content: "";
  flex: 1 1 60px;
  height: 1px;
  min-width: 32px;
  background: linear-gradient(90deg, var(--line-600), transparent);
  transform: translateY(-6px);
}
.page-about .ab-sec__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(23px, 3.6vw, 36px);
  font-weight: 900;
  line-height: 1.16;
  letter-spacing: -0.02em;
  color: var(--white-050);
}
.page-about .ab-lede {
  max-width: 66ch;
  margin: 0 0 26px;
  font-size: 16.5px;
  line-height: 1.78;
  color: var(--steel-300);
}
.page-about .ab-foot-note {
  margin: 26px 0 0;
  padding-left: 16px;
  border-left: 2px solid var(--ab-cyan);
  max-width: 62ch;
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--steel-300);
}

/* ---------- 01 四条内容线 ---------- */
.page-about .ab-lines {
  display: grid;
  gap: 14px;
  grid-template-columns: 1fr;
}
@media (min-width: 700px) {
  .page-about .ab-lines { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (min-width: 1100px) {
  .page-about .ab-lines { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}
.page-about .ab-line {
  position: relative;
  overflow: hidden;
  padding: 22px 20px 26px;
  border-radius: var(--r-md);
  background: var(--ink-800);
  border: 1px solid rgba(51, 69, 111, 0.6);
  transition: border-color 220ms var(--ease), background 220ms var(--ease);
}
.page-about .ab-line::before {
  content: "";
  position: absolute;
  inset: 0 auto auto 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, var(--ab-cyan), transparent 85%);
  transform: scaleX(0.22);
  transform-origin: left center;
  transition: transform 340ms var(--ease);
}
.page-about .ab-line:hover {
  border-color: rgba(45, 242, 214, 0.4);
  background: var(--ink-700);
}
.page-about .ab-line:hover::before { transform: scaleX(1); }
.page-about .ab-line__title {
  margin: 14px 0 10px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 800;
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--white-050);
}
.page-about .ab-line__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--steel-300);
}

/* ---------- 02 规模统计 ---------- */
.page-about .ab-stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: rgba(51, 69, 111, 0.55);
  border: 1px solid rgba(51, 69, 111, 0.55);
  border-radius: var(--r-md);
  overflow: hidden;
}
@media (min-width: 900px) {
  .page-about .ab-stats { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}
.page-about .ab-stat {
  background: var(--ink-800);
  padding: 22px 18px 20px;
  min-width: 0;
}
.page-about .ab-stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(25px, 4.2vw, 36px);
  font-weight: 600;
  line-height: 1;
  letter-spacing: 0.01em;
  color: var(--ab-cyan);
}
.page-about .ab-stat__unit {
  font-size: 0.52em;
  font-weight: 500;
  margin-left: 3px;
  letter-spacing: 0.06em;
  color: var(--steel-300);
}
.page-about .ab-stat__label {
  display: block;
  margin-top: 10px;
  font-size: 14px;
  line-height: 1.62;
  color: var(--steel-300);
}

/* ---------- 03 团队 ---------- */
.page-about .ab-team {
  display: grid;
  gap: 30px;
}
@media (min-width: 960px) {
  .page-about .ab-team {
    grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
    gap: 46px;
    align-items: start;
  }
}
.page-about .ab-team__media {
  margin: 0;
  border-radius: var(--r-md);
  overflow: hidden;
  background: var(--ink-800);
}
@media (min-width: 960px) {
  .page-about .ab-team__media { position: sticky; top: calc(var(--hdr-h) + 24px); }
}
.page-about .ab-team__media img,
.page-about .ab-journey__media img,
.page-about .ab-standards__media img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  filter: saturate(0.72) brightness(0.82);
}
.page-about .media-frame figcaption {
  padding: 10px 14px 12px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--steel-300);
  background: var(--ink-800);
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}
.page-about .ab-team__body .ab-lede { margin-bottom: 22px; }

/* 团队条形 */
.page-about .ab-bars {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 20px;
}
.page-about .ab-bar { display: block; }
.page-about .ab-bar__top {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 8px;
}
.page-about .ab-bar__role {
  font-size: 15.5px;
  font-weight: 700;
  color: var(--white-050);
}
.page-about .ab-bar__count {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--ab-cyan);
}
.page-about .ab-bar__track {
  display: block;
  height: 8px;
  border-radius: var(--r-pill);
  background: var(--ink-700);
  overflow: hidden;
}
.page-about .ab-bar__fill {
  display: block;
  height: 100%;
  border-radius: var(--r-pill);
  background: linear-gradient(90deg, var(--cyan-700), var(--ab-cyan));
  transition: width 420ms var(--ease);
}
.page-about .ab-bar:nth-child(1) .ab-bar__fill { width: 100%; }
.page-about .ab-bar:nth-child(2) .ab-bar__fill { width: 48%; }
.page-about .ab-bar:nth-child(3) .ab-bar__fill { width: 39%; }
.page-about .ab-bar:hover .ab-bar__fill { background: linear-gradient(90deg, var(--ab-cyan), var(--white-050)); }
.page-about .ab-bar__duty {
  display: block;
  margin-top: 9px;
  font-size: 14px;
  line-height: 1.65;
  color: var(--steel-300);
}

/* 处理链路 */
.page-about .ab-chain {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: rgba(51, 69, 111, 0.5);
  border: 1px solid rgba(51, 69, 111, 0.5);
  border-radius: var(--r-sm);
  overflow: hidden;
}
@media (min-width: 560px) {
  .page-about .ab-chain { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (min-width: 1100px) {
  .page-about .ab-chain { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}
.page-about .ab-chain__step {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 14px 14px 16px;
  background: var(--ink-900);
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--steel-300);
}
.page-about .ab-chain__no {
  flex: 0 0 auto;
  font-size: 12px;
  color: var(--violet-400);
}

/* ---------- 04 历程 ---------- */
.page-about .ab-sec--journey { position: relative; }
.page-about .ab-journey-layout {
  display: grid;
  gap: 34px;
}
@media (min-width: 900px) {
  .page-about .ab-journey-layout {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: 48px;
    align-items: start;
  }
}
.page-about .ab-journey {
  list-style: none;
  margin: 0;
  padding: 0 0 0 34px;
  position: relative;
}
.page-about .ab-journey::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 8px;
  bottom: 12px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--ab-cyan), var(--cyan-700) 52%, rgba(15, 110, 103, 0) 100%);
}
.page-about .ab-journey__item {
  position: relative;
  border-top: 1px solid rgba(51, 69, 111, 0.45);
}
.page-about .ab-journey__item:first-child { border-top: 0; }
.page-about .ab-journey__item::before {
  content: "";
  position: absolute;
  left: -34px;
  top: 17px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--ink-800);
  border: 2px solid var(--ab-cyan);
  box-shadow: 0 0 0 4px rgba(45, 242, 214, 0.12);
  animation: ab-pulse 1.6s ease-in-out infinite;
}
@keyframes ab-pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.45; }
}
@media (prefers-reduced-motion: reduce) {
  .page-about .ab-journey__item::before { animation: none; }
}
.page-about .ab-journey__stage { display: block; }
.page-about .ab-journey__summary {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 15px 0 13px;
  cursor: pointer;
  list-style: none;
  transition: color 180ms var(--ease);
}
.page-about .ab-journey__summary::-webkit-details-marker { display: none; }
.page-about .ab-journey__summary::marker { content: ""; }
.page-about .ab-journey__summary::after {
  content: "+";
  margin-left: auto;
  padding-left: 12px;
  font-family: var(--font-mono);
  font-size: 18px;
  line-height: 1;
  color: var(--ab-cyan);
}
.page-about .ab-journey__stage[open] > .ab-journey__summary::after { content: "–"; }
.page-about .ab-journey__summary:hover .ab-journey__name { color: var(--ab-cyan); }
.page-about .ab-journey__year {
  flex: 0 0 auto;
  min-width: 62px;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--ab-cyan);
}
.page-about .ab-journey__name {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 800;
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--white-050);
  transition: color 180ms var(--ease);
}
.page-about .ab-journey__body {
  padding: 0 0 20px 76px;
  max-width: 68ch;
}
.page-about .ab-journey__body p {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--steel-300);
}
.page-about .ab-journey__media {
  margin: 0;
  border-radius: var(--r-md);
  overflow: hidden;
  background: var(--ink-900);
}
@media (min-width: 900px) {
  .page-about .ab-journey__media { position: sticky; top: calc(var(--hdr-h) + 24px); }
}

/* ---------- 05 标准 ---------- */
.page-about .ab-standards {
  display: grid;
  gap: 30px;
}
@media (min-width: 900px) {
  .page-about .ab-standards {
    grid-template-columns: minmax(0, 6fr) minmax(0, 5fr);
    gap: 46px;
    align-items: start;
  }
}
.page-about .ab-std-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
}
.page-about .ab-std-list li {
  position: relative;
  padding: 16px 0 16px 24px;
  border-bottom: 1px solid rgba(51, 69, 111, 0.45);
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--steel-300);
}
.page-about .ab-std-list li:first-child { padding-top: 6px; }
.page-about .ab-std-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 1.55em;
  width: 11px;
  height: 2px;
  background: var(--ab-cyan);
}
.page-about .ab-std-list li strong {
  display: block;
  margin-bottom: 4px;
  color: var(--white-050);
  font-weight: 700;
}
.page-about .ab-standards__media {
  margin: 0;
  border-radius: var(--r-md);
  overflow: hidden;
  background: var(--ink-800);
}

/* ---------- 06 合作档案 ---------- */
.page-about .ab-archive { position: relative; }
.page-about .filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 22px;
}
.page-about .filter-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border-radius: var(--r-pill);
  border: 1px solid var(--line-600);
  background: rgba(27, 42, 82, 0.5);
  color: var(--steel-300);
  font-size: 14px;
  line-height: 1;
  cursor: pointer;
  transition: color 180ms var(--ease), border-color 180ms var(--ease), background 180ms var(--ease);
}
.page-about .filter-btn:hover {
  color: var(--white-050);
  border-color: var(--steel-300);
}
.page-about .filter-btn[aria-pressed="true"] {
  color: var(--ink-900);
  background: var(--ab-cyan);
  border-color: var(--ab-cyan);
}
.page-about .filter-btn .filter-count {
  font-size: 12px;
  opacity: 0.75;
}
.page-about .ab-archive__grid {
  display: grid;
  gap: 16px;
  grid-template-columns: 1fr;
}
@media (min-width: 720px) {
  .page-about .ab-archive__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
.page-about .ab-archive__card {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 20px 20px 22px;
  border-radius: var(--r-md);
  border: 1px solid rgba(51, 69, 111, 0.6);
  background: var(--ink-700);
  transition: transform 200ms var(--ease), border-color 200ms var(--ease);
}
.page-about .ab-archive__card:hover {
  transform: translateY(-3px);
  border-color: rgba(45, 242, 214, 0.5);
}
.page-about .ab-archive__card[hidden] { display: none; }
.page-about .ab-archive__card .card-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 17.5px;
  font-weight: 800;
  line-height: 1.35;
  letter-spacing: -0.01em;
  color: var(--white-050);
}
.page-about .ab-archive__card .card-body {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--steel-300);
}
.page-about .ab-archive__card .tag {
  align-self: flex-start;
  padding: 3px 10px;
  border-radius: var(--r-pill);
  border: 1px solid var(--line-600);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.05em;
  color: var(--ab-cyan);
}
.page-about .filter-empty {
  margin: 20px 0 0;
  font-size: 14px;
  color: var(--violet-400);
}

/* ---------- 页尾延伸链接 ---------- */
.page-about .ab-next {
  border-top: 1px solid rgba(51, 69, 111, 0.45);
}
.page-about .ab-next__title {
  margin: 0 0 18px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--white-050);
}
.page-about .ab-next__links {
  display: grid;
  gap: 1px;
  background: rgba(51, 69, 111, 0.45);
  border: 1px solid rgba(51, 69, 111, 0.45);
  border-radius: var(--r-sm);
  overflow: hidden;
}
@media (min-width: 760px) {
  .page-about .ab-next__links { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
.page-about .ab-next__link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 16px 18px;
  background: var(--ink-900);
  color: var(--steel-300);
  text-decoration: none;
  font-size: 15px;
  line-height: 1.5;
  transition: background 200ms var(--ease), color 200ms var(--ease);
}
.page-about .ab-next__link:hover {
  background: var(--ink-700);
  color: var(--white-050);
}
.page-about .ab-next__arrow {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  color: var(--ab-cyan);
  transition: transform 220ms var(--ease);
}
.page-about .ab-next__link:hover .ab-next__arrow { transform: translateX(4px); }

/* ---------- 窄屏收束 ---------- */
@media (max-width: 520px) {
  .page-about .ab-sec { padding: 46px 0; }
  .page-about .ab-journey { padding-left: 26px; }
  .page-about .ab-journey::before { left: 4px; }
  .page-about .ab-journey__item::before { left: -26px; top: 16px; width: 12px; height: 12px; }
  .page-about .ab-journey__year { min-width: 52px; font-size: 12px; }
  .page-about .ab-journey__body { padding-left: 0; }
  .page-about .ab-std-list li::before { top: 1.6em; }
  .page-about .about-hero__title br { display: none; }
}
<<<END>>>