.page-about {
  --about-text: 720px;
  --about-rim: rgba(31, 92, 76, 0.55);
  background: var(--ink);
  color: var(--warm);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(26px, 5vw, 56px) 0 0;
  background:
    radial-gradient(120% 95% at 88% 0%, rgba(23, 229, 200, 0.14), transparent 62%),
    radial-gradient(80% 70% at 0% 100%, rgba(255, 122, 43, 0.10), transparent 70%),
    linear-gradient(168deg, #05201A 0%, #0A0D0C 72%);
  border-bottom: 1px solid var(--edge);
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__title {
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(2.05rem, 6.4vw, 4.4rem);
  line-height: 1.05;
  letter-spacing: -0.02em;
  margin: 14px 0 0;
  max-width: 21ch;
}

.page-about .about-hero__lede {
  margin: 22px 0 0;
  max-width: 62ch;
  color: var(--warm-dim);
  font-size: clamp(1rem, 2.3vw, 1.14rem);
  line-height: 1.88;
}

.page-about .about-hero__facts {
  list-style: none;
  margin: 34px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(148px, 100%), 1fr));
  gap: 1px;
  background: var(--edge);
  border: 1px solid var(--edge);
  border-radius: var(--r);
  overflow: hidden;
}

.page-about .about-hero__facts li {
  background: var(--carbon);
  padding: 16px 18px;
}

.page-about .about-fact__value {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 300;
  font-size: clamp(1.45rem, 4.4vw, 2.05rem);
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-fact__label {
  display: block;
  margin-top: 9px;
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  color: var(--mist);
}

.page-about .about-hero__figure {
  position: relative;
  margin: clamp(30px, 5vw, 48px) 0 0;
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: clamp(180px, 32vw, 400px);
  object-fit: cover;
  opacity: 0.78;
}

.page-about .about-hero__figure::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(5, 32, 26, 0.28), rgba(5, 32, 26, 0.94));
  pointer-events: none;
}

/* ---------- 主体两栏 ---------- */
.page-about .about-body {
  max-width: var(--shell);
  margin: 0 auto;
  padding: clamp(44px, 7vw, 88px) var(--gutter) clamp(56px, 9vw, 104px);
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(30px, 5vw, 64px);
}

.page-about .about-rail {
  display: none;
}

.page-about .about-narrative {
  min-width: 0;
}

/* ---------- 年份刻度 ---------- */
.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0 0 0 18px;
  position: sticky;
  top: calc(var(--rail-h) + 34px);
  display: grid;
  gap: 0;
  border-left: 1px solid var(--edge);
}

.page-about .about-rail__link {
  display: block;
  position: relative;
  padding: 13px 0;
  text-decoration: none;
  color: var(--mist);
  transition: color 0.16s ease;
}

.page-about .about-rail__link::before {
  content: "";
  position: absolute;
  top: 50%;
  left: -19px;
  width: 9px;
  height: 1px;
  background: var(--edge);
  transform: translateY(-50%);
  transition: width 0.16s ease, background 0.16s ease;
}

.page-about .about-rail__link:hover::before,
.page-about .about-rail__link:focus-visible::before {
  width: 15px;
  background: var(--cyan);
}

.page-about .about-rail__year {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 300;
  font-size: 1.05rem;
  letter-spacing: 0.02em;
  color: var(--warm);
}

.page-about .about-rail__link:hover .about-rail__year,
.page-about .about-rail__link:focus-visible .about-rail__year {
  color: var(--cyan);
}

.page-about .about-rail__tag {
  display: block;
  margin-top: 5px;
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  color: var(--mist);
}

/* ---------- 章节 ---------- */
.page-about .chapter {
  scroll-margin-top: calc(var(--rail-h) + 28px);
  padding-bottom: clamp(46px, 7vw, 84px);
  margin-bottom: clamp(40px, 6.5vw, 76px);
  border-bottom: 1px solid var(--about-rim);
}

.page-about .chapter:last-of-type {
  border-bottom: 0;
  margin-bottom: 0;
  padding-bottom: 0;
}

.page-about .chapter__mark {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  color: var(--cyan);
}

.page-about .chapter__mark::after {
  content: "";
  flex: 1 1 auto;
  max-width: 140px;
  height: 1px;
  background: var(--edge);
}

.page-about .chapter__title {
  margin: 0;
  max-width: 24ch;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(1.6rem, 4.6vw, 2.7rem);
  line-height: 1.14;
  letter-spacing: -0.01em;
}

.page-about .chapter__lead {
  margin: 18px 0 0;
  max-width: var(--about-text);
  color: var(--mist);
  font-size: 1.02rem;
  line-height: 1.85;
}

.page-about .chapter__body {
  margin-top: 22px;
  max-width: var(--about-text);
  color: var(--warm-dim);
  font-size: 1rem;
  line-height: 1.92;
}

.page-about .chapter__body p {
  margin: 0 0 17px;
}

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

.page-about .chapter__aside {
  margin: 26px 0 0;
  font-size: 0.9rem;
  color: var(--mist);
}

.page-about .chapter__aside a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid var(--edge);
  padding-bottom: 2px;
}

.page-about .chapter__aside a:hover {
  border-bottom-color: var(--cyan);
}

/* ---------- 起点 / 今天 斜切 ---------- */
.page-about .about-split {
  margin: 36px 0 0;
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 12px 22px;
  border-radius: 6px;
  background: linear-gradient(90deg, rgba(23, 229, 200, 0.16), rgba(255, 122, 43, 0.12));
  transform: skewX(-9deg);
}

.page-about .about-split > * {
  transform: skewX(9deg);
}

.page-about .about-split__from,
.page-about .about-split__to {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 0.76rem;
  letter-spacing: 0.2em;
  color: var(--warm);
  white-space: nowrap;
}

.page-about .about-split__mid {
  flex: 1 1 auto;
  height: 1px;
  background: var(--edge);
}

/* ---------- 分工标签页 ---------- */
.page-about .tabs {
  margin-top: 30px;
}

.page-about .tabs__list {
  display: flex;
  flex-wrap: wrap;
  border-bottom: 1px solid var(--edge);
}

.page-about .tabs__tab {
  position: relative;
  appearance: none;
  background: transparent;
  border: 0;
  margin: 0 26px 0 0;
  padding: 12px 2px;
  font-family: var(--font-body);
  font-size: 0.94rem;
  letter-spacing: 0.04em;
  color: var(--mist);
  cursor: pointer;
  transition: color 0.16s ease;
}

.page-about .tabs__tab::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  background: transparent;
  transition: background 0.16s ease;
}

.page-about .tabs__tab:hover {
  color: var(--cyan);
}

.page-about .tabs__tab[aria-selected="true"] {
  color: var(--warm);
}

.page-about .tabs__tab[aria-selected="true"]::after {
  background: var(--cyan);
}

.page-about .tabs__panel {
  margin-top: 28px;
  padding: clamp(20px, 3vw, 30px);
  background: var(--pitch);
  border: 1px solid var(--edge);
  border-radius: 0 var(--r) var(--r) var(--r);
}

.page-about .tabs__panel + .tabs__panel {
  margin-top: 16px;
}

.page-about .team__name {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-weight: 400;
  font-size: 1.16rem;
  line-height: 1.4;
  color: var(--warm);
}

.page-about .tabs__panel p {
  margin: 0;
  max-width: var(--about-text);
  color: var(--warm-dim);
  font-size: 0.98rem;
  line-height: 1.88;
}

.page-about .team__list {
  list-style: none;
  margin: 20px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .team__list li {
  position: relative;
  padding-left: 20px;
  font-size: 0.92rem;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .team__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 10px;
  height: 1px;
  background: var(--orange);
}

/* ---------- 合作点阵 ---------- */
.page-about .partners {
  margin-top: 34px;
  display: grid;
  gap: 24px;
}

.page-about .partners__figure {
  margin: 0;
  border: 1px solid var(--edge);
  border-radius: var(--r);
  overflow: hidden;
  background: var(--carbon);
}

.page-about .partners__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 9 / 7;
  object-fit: cover;
  opacity: 0.85;
}

.page-about .pindex {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(190px, 100%), 1fr));
  gap: 10px;
}

.page-about .pindex__item {
  position: relative;
  padding: 14px 16px 14px 42px;
  background: rgba(18, 51, 41, 0.6);
  border: 1px solid var(--edge);
  border-radius: var(--r-sm);
  transition: border-color 0.16s ease, background 0.16s ease, transform 0.16s ease;
}

.page-about .pindex__item:hover {
  border-color: var(--cyan);
  background: rgba(18, 51, 41, 0.92);
  transform: translateY(-2px);
}

.page-about .pindex__dot {
  position: absolute;
  left: 16px;
  top: 21px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--edge);
  transition: background 0.16s ease, box-shadow 0.16s ease;
}

.page-about .pindex__item:hover .pindex__dot {
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(23, 229, 200, 0.16);
}

.page-about .pindex__text {
  display: block;
  font-size: 0.94rem;
  line-height: 1.5;
  color: var(--warm);
}

.page-about .pindex__note {
  display: block;
  margin-top: 7px;
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  font-size: 0.8rem;
  line-height: 1.5;
  color: var(--mist);
  transition: max-height 0.2s ease, opacity 0.2s ease;
}

.page-about .pindex__item:hover .pindex__note,
.page-about .pindex__item:focus-within .pindex__note {
  max-height: 5em;
  opacity: 1;
}

/* ---------- 版本时间线 ---------- */
.page-about .versions__figure {
  margin: 32px 0 0;
  border: 1px solid var(--edge);
  border-radius: var(--r);
  overflow: hidden;
  background: var(--carbon);
}

.page-about .versions__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 5 / 3;
  object-fit: cover;
}

.page-about .versions__figure figcaption {
  padding: 12px 16px;
  font-size: 0.8rem;
  letter-spacing: 0.02em;
  color: var(--mist);
  border-top: 1px solid var(--edge);
}

.page-about .versions {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
}

.page-about .versions__item {
  position: relative;
  padding: 20px 0 20px 22px;
  border-left: 1px solid var(--edge);
}

.page-about .versions__item::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 26px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--ink);
  border: 1px solid var(--cyan);
}

.page-about .versions__year {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.page-about .versions__title {
  margin: 8px 0 0;
  font-family: var(--font-display);
  font-weight: 400;
  font-size: 1.08rem;
  line-height: 1.45;
  color: var(--warm);
}

.page-about .versions__body p {
  margin: 8px 0 0;
  max-width: var(--about-text);
  color: var(--warm-dim);
  font-size: 0.94rem;
  line-height: 1.85;
}

/* ---------- 服务闭环 ---------- */
.page-about .flow {
  list-style: none;
  margin: 32px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--edge);
  border: 1px solid var(--edge);
  border-radius: var(--r);
  overflow: hidden;
}

.page-about .flow__item {
  background: var(--pitch);
  padding: 22px 20px;
}

.page-about .flow__num {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 300;
  font-size: 1.7rem;
  line-height: 1;
  color: var(--orange);
}

.page-about .flow__title {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 400;
  font-size: 1.02rem;
  line-height: 1.45;
  color: var(--warm);
}

.page-about .flow__item p {
  margin: 9px 0 0;
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 结尾行动 ---------- */
.page-about .about-cta {
  margin-top: clamp(40px, 7vw, 72px);
  padding: clamp(26px, 4.5vw, 44px) clamp(20px, 4vw, 40px);
  border: 1px solid var(--edge);
  border-left: 3px solid var(--orange);
  border-radius: var(--r);
  background: linear-gradient(125deg, rgba(23, 229, 200, 0.12), rgba(255, 122, 43, 0.10));
}

.page-about .about-cta__title {
  margin: 14px 0 0;
  max-width: 22ch;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(1.4rem, 3.8vw, 2.1rem);
  line-height: 1.18;
}

.page-about .about-cta__text {
  margin: 18px 0 0;
  max-width: 60ch;
  color: var(--warm-dim);
  font-size: 0.98rem;
  line-height: 1.88;
}

.page-about .about-cta__actions {
  margin-top: 26px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .partners {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1fr);
    align-items: start;
  }

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

  .page-about .versions__item {
    display: grid;
    grid-template-columns: 118px minmax(0, 1fr);
    gap: 8px 20px;
    align-items: start;
  }

  .page-about .versions__year {
    padding-top: 6px;
  }

  .page-about .versions__title {
    margin-top: 0;
  }
}

@media (min-width: 900px) {
  .page-about .about-body {
    grid-template-columns: 116px minmax(0, 1fr);
    gap: clamp(40px, 6vw, 84px);
  }

  .page-about .about-rail {
    display: block;
  }

  .page-about .about-hero__title {
    max-width: 20ch;
  }

  .page-about .about-hero__lede {
    font-size: 1.14rem;
  }
}

@media (min-width: 1040px) {
  .page-about .flow {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .pindex__item,
  .page-about .pindex__dot,
  .page-about .pindex__note,
  .page-about .tabs__tab,
  .page-about .tabs__tab::after,
  .page-about .about-rail__link,
  .page-about .about-rail__link::before {
    transition: none;
  }

  .page-about .pindex__item:hover {
    transform: none;
  }
}
<<<END>>>