.page-about{
  --about-rail: 220px;
  --about-ink-soft: rgba(244,239,230,.86);
  --about-ink-dim: rgba(244,239,230,.62);
  padding-top: var(--header-h);
  background: var(--ink);
  color: var(--paper);
  font-family: var(--font-body);
  font-size: var(--fs-body);
  line-height: 1.75;
}

.page-about .mono{ font-family: var(--font-mono); letter-spacing: .04em; }

/* ---------- 首屏门廊 ---------- */
.page-about .about-hero{
  position: relative;
  padding: clamp(20px,3vw,36px) 0 clamp(36px,5vw,64px);
  background:
    radial-gradient(95% 70% at 50% 0%, rgba(217,164,65,.18) 0%, rgba(14,26,43,0) 64%),
    linear-gradient(180deg, #0B1524 0%, var(--ink) 100%);
  border-bottom: 1px solid var(--gold-line);
  overflow: hidden;
}
.page-about .about-hero::after{
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(140,154,170,.08) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(140,154,170,.08) 1px, transparent 1px);
  background-size: 48px 48px;
  -webkit-mask-image: linear-gradient(180deg, rgba(0,0,0,.85), rgba(0,0,0,0) 78%);
  mask-image: linear-gradient(180deg, rgba(0,0,0,.85), rgba(0,0,0,0) 78%);
}
.page-about .about-crumbs{ position: relative; z-index: 1; margin-bottom: clamp(16px,2vw,24px); }
.page-about .about-hero__frame{
  position: relative;
  z-index: 1;
  padding: clamp(24px,4vw,52px) clamp(20px,4vw,48px);
  background: rgba(23,41,63,.52);
}
.page-about .about-hero__eyebrow{
  margin: 0 0 16px;
  font-size: var(--fs-micro);
  letter-spacing: .18em;
  font-weight: 700;
  color: var(--gold-hi);
}
.page-about .about-hero__title{
  margin: 0 0 20px;
  max-width: 20ch;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: var(--fs-h1);
  line-height: 1.2;
  letter-spacing: -.02em;
  color: var(--paper);
  text-shadow: 0 0 2px rgba(217,164,65,.55);
}
.page-about .about-hero__lede{
  margin: 0;
  max-width: 62ch;
  font-size: var(--fs-body);
  line-height: 1.85;
  color: var(--about-ink-soft);
}
.page-about .about-facts{
  list-style: none;
  margin: clamp(24px,3vw,36px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0,1fr));
  gap: 1px;
  background: var(--gold-line);
  border: 1px solid var(--gold-line);
}
.page-about .about-facts li{
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 14px 16px;
  background: var(--ink-2);
  min-width: 0;
}
.page-about .about-facts__num{
  font-family: var(--font-mono);
  font-size: clamp(1.35rem,2.4vw,1.75rem);
  line-height: 1.1;
  letter-spacing: .04em;
  color: var(--gold-hi);
}
.page-about .about-facts__key{
  font-size: var(--fs-micro);
  letter-spacing: .06em;
  color: var(--stone);
}
.page-about .about-hero__actions{
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(20px,3vw,28px);
}

/* ---------- 章节外壳 ---------- */
.page-about .about-shell{
  display: grid;
  grid-template-columns: 1fr;
  padding-top: clamp(28px,4vw,56px);
  padding-bottom: clamp(48px,7vw,96px);
}
.page-about .about-stream{ min-width: 0; }

/* ---------- 左侧年份 / 章节索引 ---------- */
.page-about .about-rail{
  margin-bottom: 32px;
  padding-top: 12px;
  border-top: 2px solid var(--gold);
  min-width: 0;
}
.page-about .about-rail__label{
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: var(--fs-micro);
  letter-spacing: .18em;
  color: var(--stone);
}
.page-about .about-rail .toc__list{
  list-style: none;
  margin: 0;
  padding: 0 0 6px;
  display: flex;
  gap: 6px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}
.page-about .about-rail .toc__link{
  display: block;
  min-height: 44px;
  padding: 10px 12px;
  white-space: nowrap;
  font-size: var(--fs-small);
  color: var(--stone);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: color 160ms var(--ease), border-color 160ms var(--ease);
}
.page-about .about-rail .toc__link:hover,
.page-about .about-rail .toc__link:focus-visible{
  color: var(--gold-hi);
}
.page-about .about-rail .toc__link[aria-current="true"]{
  color: var(--gold-hi);
  border-bottom-color: var(--flag-blue);
}

/* ---------- 章节通用 ---------- */
.page-about .about-sec{
  padding: clamp(36px,5.5vw,68px) 0;
  border-bottom: 1px solid var(--gold-line);
  scroll-margin-top: calc(var(--header-h) + 24px);
}
.page-about .about-sec:first-child{ padding-top: 0; }
.page-about .about-sec:last-of-type{ border-bottom: 0; }

.page-about .about-band{
  display: flex;
  gap: 4px;
  margin-bottom: 18px;
}
.page-about .about-band i{ display: block; width: 26px; height: 4px; }
.page-about .about-band i:nth-child(1){ background: var(--flag-blue); }
.page-about .about-band i:nth-child(2){ background: var(--paper); }
.page-about .about-band i:nth-child(3){ background: var(--cinnabar); }
.page-about .about-band i:nth-child(4){ background: var(--flag-green); }
.page-about .about-band i:nth-child(5){ background: var(--gold); }

.page-about .about-sec__head{
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 22px;
}
.page-about .about-sec__no{
  flex: none;
  font-family: var(--font-mono);
  font-size: var(--fs-small);
  letter-spacing: .12em;
  color: var(--gold);
}
.page-about .about-sec__title{
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: var(--fs-h2);
  line-height: 1.32;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .about-p{
  margin: 0 0 16px;
  max-width: 66ch;
  color: var(--about-ink-soft);
  line-height: 1.85;
}
.page-about .about-p--tight{ margin-bottom: 12px; font-size: var(--fs-small); }

.page-about .about-note{
  margin: 22px 0 0;
  padding: 14px 16px;
  max-width: 66ch;
  font-size: var(--fs-small);
  line-height: 1.75;
  color: var(--gold-hi);
  background: rgba(246,223,166,.07);
  border-left: 2px solid var(--gold);
}

.page-about .about-list{
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  max-width: 62ch;
}
.page-about .about-list li{
  position: relative;
  padding-left: 18px;
  margin-bottom: 10px;
  font-size: var(--fs-small);
  line-height: 1.75;
  color: var(--about-ink-soft);
}
.page-about .about-list li::before{
  content: "";
  position: absolute;
  left: 0;
  top: .72em;
  width: 6px;
  height: 6px;
  background: var(--gold);
  transform: rotate(45deg);
}

/* ---------- 立项关键节点 ---------- */
.page-about .about-milestones{
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  border-top: 1px solid var(--gold-line);
}
.page-about .about-milestones__item{
  display: grid;
  grid-template-columns: 68px minmax(0,1fr);
  gap: 12px;
  align-items: baseline;
  padding: 12px 0;
  border-bottom: 1px solid var(--gold-line);
}
.page-about .about-milestones__year{
  font-family: var(--font-mono);
  font-size: var(--fs-small);
  color: var(--gold-hi);
  letter-spacing: .06em;
}
.page-about .about-milestones__text{
  font-size: var(--fs-small);
  line-height: 1.7;
  color: var(--about-ink-soft);
}

/* ---------- 版本时间轴 ---------- */
.page-about .about-timeline-wrap{ margin-top: 8px; }

.page-about .vtl{
  --vtl-pad: clamp(18px,3vw,30px);
  margin: 0;
  padding: 0 0 0 var(--vtl-pad);
  border-left: 1px solid var(--gold-line-strong);
}
.page-about .vtl__item{
  position: relative;
  border: 0;
  background: none;
}
.page-about .vtl__item::before{
  content: "";
  position: absolute;
  left: calc(-1 * var(--vtl-pad) - 4.5px);
  top: 22px;
  width: 8px;
  height: 8px;
  background: var(--gold);
  transition: background 160ms var(--ease);
}
.page-about .vtl__item:hover::before{ background: var(--gold-hi); }

.page-about .vtl__head{ margin: 0; font-size: inherit; font-weight: inherit; }

.page-about .vtl__trigger{
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 8px 12px;
  width: 100%;
  min-height: 48px;
  padding: 14px 0;
  border: 0;
  border-bottom: 1px solid var(--gold-line);
  background: none;
  color: var(--paper);
  font-family: inherit;
  font-size: var(--fs-body);
  text-align: left;
  cursor: pointer;
  transition: color 160ms var(--ease);
}
.page-about .vtl__trigger:hover,
.page-about .vtl__trigger:focus-visible{ color: var(--gold-hi); }
.page-about .vtl__ver{
  flex: none;
  min-width: 56px;
  font-family: var(--font-mono);
  font-size: var(--fs-small);
  letter-spacing: .04em;
  color: var(--gold-hi);
}
.page-about .vtl__name{ flex: 1 1 12ch; min-width: 0; }
.page-about .vtl__flag{
  flex: none;
  padding: 1px 6px;
  font-size: var(--fs-micro);
  letter-spacing: .12em;
  color: var(--flag-green-hi);
  border: 1px solid rgba(111,196,143,.42);
}
.page-about .vtl .accordion__inner{
  padding: 6px 0 18px;
  max-width: 60ch;
  font-size: var(--fs-small);
  line-height: 1.8;
  color: var(--about-ink-soft);
}
.page-about .vtl .accordion__inner p{ margin: 0; }

.page-about .about-timeline-fig{
  margin: 26px 0 0;
  max-width: 320px;
}

/* ---------- 编目原则 ---------- */
.page-about .about-pair{
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(20px,3vw,32px);
}
.page-about .about-pair__fig{ margin: 0; }
.page-about .about-pair__text{ min-width: 0; }

/* ---------- 服务范围 ---------- */
.page-about .about-coverage{
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(20px,3vw,32px);
  margin-top: 8px;
}
.page-about .about-coverage__map{ min-width: 0; }
.page-about .about-map{
  display: block;
  width: 100%;
  max-width: 420px;
  height: auto;
}
.page-about .about-map__cell{
  fill: var(--flag-green);
  fill-opacity: .78;
  stroke: rgba(14,26,43,.55);
  stroke-width: 1;
  transition: fill 160ms var(--ease), fill-opacity 160ms var(--ease);
}
.page-about .about-map__cell:hover{ fill: var(--gold-hi); fill-opacity: 1; }
.page-about .about-map__cell--pending{
  fill: var(--cinnabar);
  fill-opacity: .82;
  stroke: var(--gold);
  stroke-width: 1.5;
}
.page-about .about-map__cell--pending:hover{ fill: var(--cinnabar-hi); fill-opacity: 1; }

.page-about .about-legend{
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  margin: 16px 0 0;
  padding: 0;
  font-size: var(--fs-micro);
  letter-spacing: .06em;
  color: var(--stone);
}
.page-about .about-legend li{ display: flex; align-items: center; gap: 8px; }
.page-about .about-legend__dot{ width: 12px; height: 12px; flex: none; }
.page-about .about-legend__dot--on{ background: var(--flag-green); }
.page-about .about-legend__dot--pending{ background: var(--cinnabar); border: 1px solid var(--gold); }

.page-about .about-coverage__side{ min-width: 0; }
.page-about .about-meter{
  border: 1px solid var(--gold-line);
  background: var(--ink-2);
  padding: 16px;
  margin-bottom: 18px;
}
.page-about .about-meter__head{
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 12px;
  font-size: var(--fs-small);
  color: var(--about-ink-soft);
}
.page-about .about-meter__head .mono{ color: var(--gold-hi); font-size: var(--fs-small); }
.page-about .about-meter__track{
  height: 10px;
  background: rgba(140,154,170,.18);
  overflow: hidden;
}
.page-about .about-meter__fill{
  display: block;
  width: 90.3%;
  height: 100%;
  background: linear-gradient(90deg, var(--flag-green), var(--flag-green-hi));
}
.page-about .about-coverage__cta{ margin-top: 4px; }
.page-about .about-coverage-fig{ margin: 26px 0 0; }

/* ---------- 团队分工 ---------- */
.page-about .about-roles{
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  border-top: 1px solid var(--gold-line);
}
.page-about .about-roles__item{
  display: grid;
  grid-template-columns: 64px minmax(0,1fr);
  gap: 14px;
  align-items: start;
  padding: 18px 0;
  border-bottom: 1px solid var(--gold-line);
}
.page-about .about-roles__no{
  font-family: var(--font-mono);
  font-size: clamp(1.5rem,3vw,2rem);
  line-height: 1;
  letter-spacing: .02em;
  color: var(--gold);
}
.page-about .about-roles__body{ min-width: 0; }
.page-about .about-roles__name{
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: var(--fs-h3);
  line-height: 1.4;
  color: var(--paper);
}
.page-about .about-roles__desc{
  margin: 0;
  max-width: 58ch;
  font-size: var(--fs-small);
  line-height: 1.8;
  color: var(--about-ink-dim);
}

/* ---------- 运营中心 ---------- */
.page-about .about-reach{
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(20px,3vw,32px);
}
.page-about .about-reach__list{
  margin: 0;
  border-top: 1px solid var(--gold-line);
}
.page-about .about-reach__row{
  display: grid;
  grid-template-columns: 1fr;
  gap: 2px;
  padding: 14px 0;
  border-bottom: 1px solid var(--gold-line);
}
.page-about .about-reach__key{
  font-size: var(--fs-micro);
  letter-spacing: .14em;
  color: var(--stone);
}
.page-about .about-reach__val{
  margin: 0;
  font-size: var(--fs-small);
  line-height: 1.7;
  color: var(--about-ink-soft);
  word-break: break-word;
}
.page-about .about-reach__val.mono{ color: var(--gold-hi); }
.page-about .about-reach__side{ min-width: 0; }

/* ---------- 下一步 ---------- */
.page-about .about-next{
  margin-top: clamp(36px,5vw,64px);
  padding: clamp(24px,4vw,40px) clamp(20px,3vw,32px);
  border: 1px solid var(--gold-line-strong);
  background:
    linear-gradient(180deg, rgba(217,164,65,.08), rgba(23,41,63,.6));
}
.page-about .about-next__title{
  margin: 0 0 20px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: var(--fs-h3);
  color: var(--paper);
  letter-spacing: .02em;
}
.page-about .about-next__grid{
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--gold-line);
  border: 1px solid var(--gold-line);
}
.page-about .about-next__link{
  display: block;
  padding: 16px 18px;
  background: var(--ink-2);
  text-decoration: none;
  color: var(--about-ink-soft);
  min-height: 44px;
  transition: background 160ms var(--ease), color 160ms var(--ease);
}
.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible{
  background: rgba(217,164,65,.12);
  color: var(--paper);
}
.page-about .about-next__label{
  display: block;
  margin-bottom: 6px;
  font-family: var(--font-mono);
  font-size: var(--fs-micro);
  letter-spacing: .16em;
  color: var(--gold-hi);
}
.page-about .about-next__text{
  display: block;
  font-size: var(--fs-small);
  line-height: 1.65;
}

/* ---------- 断点 ---------- */
@media (min-width: 640px){
  .page-about .about-reach__row{
    grid-template-columns: 128px minmax(0,1fr);
    gap: 16px;
    align-items: baseline;
  }
  .page-about .about-next__grid{ grid-template-columns: repeat(3, minmax(0,1fr)); }
}

@media (min-width: 720px){
  .page-about .about-facts{ grid-template-columns: repeat(4, minmax(0,1fr)); }
}

@media (min-width: 900px){
  .page-about .about-pair{
    grid-template-columns: minmax(0,1.15fr) minmax(0,1fr);
    align-items: start;
  }
  .page-about .about-coverage{
    grid-template-columns: minmax(0,1.1fr) minmax(0,1fr);
    align-items: start;
  }
  .page-about .about-reach{
    grid-template-columns: minmax(0,1.2fr) minmax(0,1fr);
    align-items: start;
  }
  .page-about .about-timeline-wrap{
    display: grid;
    grid-template-columns: minmax(0,1fr) 260px;
    gap: clamp(24px,3vw,40px);
    align-items: start;
  }
  .page-about .about-timeline-fig{
    margin: 0;
    max-width: none;
    position: sticky;
    top: calc(var(--header-h) + 24px);
  }
}

@media (min-width: 960px){
  .page-about .about-shell{
    grid-template-columns: var(--about-rail) minmax(0,1fr);
    column-gap: clamp(32px,4vw,64px);
    align-items: start;
  }
  .page-about .about-rail{
    position: sticky;
    top: calc(var(--header-h) + 24px);
    margin-bottom: 0;
    padding-top: 16px;
    max-height: calc(100vh - var(--header-h) - 48px);
    overflow-y: auto;
  }
  .page-about .about-rail .toc__list{
    flex-direction: column;
    gap: 0;
    padding-bottom: 0;
    overflow: visible;
  }
  .page-about .about-rail .toc__link{
    padding: 10px 0 10px 14px;
    border-bottom: 0;
    border-left: 2px solid transparent;
    white-space: normal;
  }
  .page-about .about-rail .toc__link[aria-current="true"]{
    border-left-color: var(--flag-blue);
    border-bottom-color: transparent;
    background: linear-gradient(90deg, rgba(42,167,155,.16), rgba(42,167,155,0));
  }
}

@media (prefers-reduced-motion: reduce){
  .page-about *,
  .page-about *::before,
  .page-about *::after{
    transition-duration: 1ms !important;
    animation-duration: 1ms !important;
    animation-iteration-count: 1 !important;
  }
}
<<<END>>>