.page-about {
  --about-pad: clamp(2.5rem, 6vw, 4.5rem);
  --about-rule: var(--line-soft);
  position: relative;
  overflow-x: clip;
  color: var(--text);
  background: var(--ink);
}

/* ── 首屏 ───────────────────────────────── */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-block: clamp(1.25rem, 3.5vw, 2.25rem) clamp(2.5rem, 6vw, 4.5rem);
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(ellipse 68% 88% at 86% 6%, rgba(18, 224, 200, 0.16), transparent 62%),
    radial-gradient(ellipse 46% 66% at 102% 92%, rgba(255, 106, 31, 0.11), transparent 60%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: 0.55;
  background-image:
    linear-gradient(to right, rgba(42, 53, 64, 0.34) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(42, 53, 64, 0.34) 1px, transparent 1px);
  background-size: 94px 94px;
  -webkit-mask-image: radial-gradient(ellipse 82% 74% at 46% 18%, #000, transparent 80%);
  mask-image: radial-gradient(ellipse 82% 74% at 46% 18%, #000, transparent 80%);
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1rem;
}

.page-about .about-hero__eyebrow {
  margin: 0;
  color: var(--cyan);
}

.page-about .about-hero__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(2rem, 7.2vw, 4.6rem);
  font-weight: 600;
  line-height: 1.04;
  letter-spacing: -0.02em;
  color: var(--text);
  text-wrap: balance;
}

.page-about .about-hero__lede {
  margin: 0;
  max-width: 58ch;
  font-size: clamp(0.9375rem, 1.5vw, 1.0625rem);
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-hero__facts {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 1.5rem;
  margin-top: 0.5rem;
}

.page-about .fact {
  flex: 1 1 9rem;
  min-width: 0;
  padding-left: 0.9rem;
  border-left: 1px solid var(--line);
}

.page-about .fact__value {
  display: block;
  font-family: var(--font-display);
  font-size: clamp(2rem, 6vw, 3.4rem);
  line-height: 0.92;
  letter-spacing: -0.02em;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .fact--alt .fact__value {
  color: var(--orange);
}

.page-about .fact__label {
  display: block;
  margin-top: 0.45rem;
  font-size: 0.8125rem;
  line-height: 1.6;
  letter-spacing: 0.02em;
  color: var(--muted);
}

@media (min-width: 900px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    grid-template-areas:
      "crumb   crumb"
      "eyebrow eyebrow"
      "title   facts"
      "lede    facts";
    column-gap: clamp(1.5rem, 4vw, 3.5rem);
    row-gap: 1.1rem;
    align-items: start;
  }

  .page-about .breadcrumb { grid-area: crumb; }
  .page-about .about-hero__eyebrow { grid-area: eyebrow; }
  .page-about .about-hero__title { grid-area: title; }
  .page-about .about-hero__lede { grid-area: lede; }
  .page-about .about-hero__facts { grid-area: facts; }

  .page-about .about-hero__facts {
    flex-direction: column;
    gap: 0;
    margin-top: 0;
  }

  .page-about .fact {
    flex: none;
    padding: 0.9rem 0 0.9rem 0.9rem;
    border-top: 1px solid var(--line-soft);
  }

  .page-about .fact:first-child {
    border-top: 0;
    padding-top: 0;
  }
}

/* ── 画布与索引轨 ───────────────────────── */
.page-about .about-canvas {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  padding-block: 0;
}

.page-about .about-index {
  padding-block: 1.25rem;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-index__title {
  margin: 0 0 0.7rem;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-index__list {
  display: flex;
  gap: 0.3rem 0.5rem;
  margin: 0;
  padding: 0 0 0.35rem;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-index__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-index__link {
  display: flex;
  align-items: baseline;
  gap: 0.45rem;
  white-space: nowrap;
  padding: 0.5rem 0.8rem;
  font-size: 0.8125rem;
  line-height: 1.3;
  color: var(--muted);
  text-decoration: none;
  border: 1px solid var(--line-soft);
  border-radius: 999px;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease), background-color 0.2s var(--ease);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--text);
  border-color: var(--cyan);
  background-color: rgba(18, 224, 200, 0.07);
}

.page-about .about-index__num {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.1em;
  color: var(--cyan-deep);
}

@media (min-width: 1024px) {
  .page-about .about-canvas {
    grid-template-columns: 152px minmax(0, 1fr);
    column-gap: clamp(1.75rem, 4vw, 4rem);
  }

  .page-about .about-index {
    position: sticky;
    top: calc(var(--bar-h) + 1.5rem);
    align-self: start;
    max-height: calc(100vh - var(--bar-h) - 3rem);
    overflow-y: auto;
    padding-block: 3rem 2rem;
    padding-right: 1rem;
    border-bottom: 0;
    border-right: 1px solid var(--line-soft);
    scrollbar-width: thin;
  }

  .page-about .about-index__list {
    flex-direction: column;
    gap: 0;
    padding-bottom: 0;
    overflow: visible;
  }

  .page-about .about-index__link {
    padding: 0.6rem 0 0.6rem 0.75rem;
    border: 0;
    border-left: 1px solid var(--line);
    border-radius: 0;
  }
}

.page-about .about-flow {
  min-width: 0;
  padding-bottom: clamp(2.5rem, 6vw, 4rem);
}

/* ── 章节通用 ───────────────────────────── */
.page-about .about-section {
  padding-block: var(--about-pad);
  border-top: 1px solid var(--line-soft);
  scroll-margin-top: calc(var(--bar-h) + 1.5rem);
}

.page-about .about-section:first-child {
  border-top: 0;
}

.page-about .about-section__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  grid-template-areas:
    "num title"
    ".   lede";
  column-gap: 1rem;
  row-gap: 0.6rem;
  align-items: start;
  margin-bottom: clamp(1.5rem, 3vw, 2.25rem);
}

.page-about .about-section__num {
  grid-area: num;
  padding-top: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .about-section__title {
  grid-area: title;
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(1.55rem, 4.6vw, 2.9rem);
  font-weight: 300;
  line-height: 1.08;
  letter-spacing: -0.01em;
  color: var(--text);
  text-wrap: balance;
}

.page-about .about-section__lede {
  grid-area: lede;
  margin: 0;
  max-width: 62ch;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-text {
  margin: 0 0 1rem;
  max-width: 66ch;
  font-size: 0.9375rem;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-media {
  margin: 0 0 clamp(1.5rem, 3vw, 2.25rem);
  overflow: hidden;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: var(--panel);
}

.page-about .about-media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-media figcaption {
  padding: 0.7rem 0.9rem;
  border-top: 1px solid var(--line-soft);
  font-family: var(--font-mono);
  font-size: 0.625rem;
  line-height: 1.7;
  letter-spacing: 0.1em;
  color: var(--muted);
}

/* ── 时间轴 ─────────────────────────────── */
.page-about .about-timeline {
  position: relative;
  margin: 0;
  padding: 0 0 0 1.5rem;
  list-style: none;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 0.6rem;
  bottom: 1.2rem;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan), var(--line) 55%, transparent);
}

.page-about .about-timeline__item {
  position: relative;
  padding-bottom: clamp(1.4rem, 3vw, 2.1rem);
}

.page-about .about-timeline__item:last-child {
  padding-bottom: 0;
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: calc(-1.5rem + 1px);
  top: 0.5rem;
  width: 9px;
  height: 9px;
  box-sizing: border-box;
  border: 1px solid var(--cyan);
  border-radius: 50%;
  background: var(--ink);
  box-shadow: 0 0 0 4px rgba(18, 224, 200, 0.1);
}

.page-about .about-timeline__year {
  display: block;
  margin-bottom: 0.3rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  color: var(--orange);
  font-variant-numeric: tabular-nums;
}

.page-about .about-timeline__title {
  margin: 0 0 0.4rem;
  font-size: 1.0625rem;
  font-weight: 600;
  line-height: 1.55;
  color: var(--text);
}

.page-about .about-timeline__body .about-text {
  margin-bottom: 0;
}

@media (min-width: 720px) {
  .page-about .about-timeline__item {
    display: grid;
    grid-template-columns: 8rem minmax(0, 1fr);
    column-gap: 1.5rem;
    align-items: start;
  }

  .page-about .about-timeline__year {
    padding-top: 0.35rem;
    margin-bottom: 0;
  }
}

/* ── 覆盖范围 ───────────────────────────── */
.page-about .coverage-figure {
  margin: 0 0 clamp(1.5rem, 3vw, 2.25rem);
  padding: clamp(0.75rem, 2vw, 1.25rem);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: linear-gradient(150deg, var(--panel) 0%, var(--ink-2) 100%);
}

.page-about .coverage-map {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .coverage-map__spoke {
  stroke: var(--line);
  stroke-width: 1;
  opacity: 0.5;
}

.page-about .coverage-map__hub {
  fill: var(--orange);
}

.page-about .coverage-map__zone {
  fill: rgba(18, 224, 200, 0.12);
  stroke: var(--line);
  stroke-width: 1;
  transition: fill 0.25s var(--ease), stroke 0.25s var(--ease);
}

.page-about .coverage-map__zone:hover {
  fill: rgba(18, 224, 200, 0.4);
  stroke: var(--cyan);
}

.page-about .coverage-figure__cap {
  margin-top: 0.75rem;
  padding-top: 0.6rem;
  border-top: 1px solid var(--line-soft);
  font-family: var(--font-mono);
  font-size: 0.625rem;
  line-height: 1.75;
  letter-spacing: 0.09em;
  color: var(--muted);
}

.page-about .coverage-stats {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1rem;
  margin: 0 0 clamp(1.25rem, 3vw, 1.75rem);
  padding: 0;
  list-style: none;
}

.page-about .coverage-stat {
  padding-top: 0.85rem;
  border-top: 1px solid var(--line);
}

.page-about .coverage-stat__value {
  display: block;
  font-family: var(--font-display);
  font-size: clamp(2rem, 5vw, 2.9rem);
  line-height: 0.95;
  letter-spacing: -0.02em;
  color: var(--text);
  font-variant-numeric: tabular-nums;
}

.page-about .coverage-stat__label {
  display: block;
  margin-top: 0.45rem;
  font-size: 0.8125rem;
  line-height: 1.65;
  color: var(--muted);
}

@media (min-width: 620px) {
  .page-about .coverage-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.25rem;
  }
}

/* ── 团队 ───────────────────────────────── */
.page-about .team-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .team-item {
  position: relative;
  padding: 1.25rem 0 1.25rem 1.15rem;
  border-bottom: 1px solid var(--line-soft);
  transition: background-color 0.25s var(--ease);
}

.page-about .team-item:first-child {
  border-top: 1px solid var(--line-soft);
}

.page-about .team-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 1.25rem;
  bottom: 1.25rem;
  width: 2px;
  background: var(--line);
  transition: background-color 0.25s var(--ease);
}

.page-about .team-item:hover::before,
.page-about .team-item:focus-within::before {
  background: var(--cyan);
}

.page-about .team-item:hover,
.page-about .team-item:focus-within {
  background-color: rgba(18, 224, 200, 0.035);
}

.page-about .team-item__head {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  margin-bottom: 0.4rem;
}

.page-about .team-item__count {
  min-width: 2.2ch;
  font-family: var(--font-display);
  font-size: 1.75rem;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .team-item__name {
  margin: 0;
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--text);
}

.page-about .team-item__desc {
  margin: 0 0 0.35rem;
  max-width: 64ch;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .team-item__faq {
  margin: 0;
  max-width: 64ch;
  font-size: 0.8125rem;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .team-item__faq-tag {
  display: inline-block;
  margin-right: 0.5rem;
  padding: 0 0.45rem;
  border: 1px solid rgba(255, 106, 31, 0.45);
  border-radius: 3px;
  font-family: var(--font-mono);
  font-size: 0.625rem;
  line-height: 1.7;
  letter-spacing: 0.1em;
  color: var(--orange);
  vertical-align: 1px;
}

/* ── 版本演进 ───────────────────────────── */
.page-about .version-track {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.35rem;
  margin: 0 0 clamp(1.25rem, 3vw, 1.75rem);
  padding: 0;
  list-style: none;
}

.page-about .version-item {
  position: relative;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
}

.page-about .version-item::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: 38px;
  height: 1px;
  background: var(--cyan);
}

.page-about .version-item__tag {
  display: inline-block;
  margin-bottom: 0.3rem;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
  color: var(--orange);
  text-transform: uppercase;
}

.page-about .version-item__title {
  margin: 0 0 0.4rem;
  font-size: 1rem;
  font-weight: 600;
  line-height: 1.55;
  color: var(--text);
}

.page-about .version-item .about-text {
  margin: 0;
  font-size: 0.875rem;
}

@media (min-width: 760px) {
  .page-about .version-track {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: clamp(1.5rem, 4vw, 3rem);
    row-gap: 1.75rem;
  }
}

/* ── 接入流程 ───────────────────────────── */
.page-about .flow-steps {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.15rem;
  margin: 0 0 clamp(1.5rem, 3vw, 2.25rem);
  padding: 0;
  list-style: none;
}

.page-about .flow-step {
  position: relative;
  padding-left: 1.15rem;
  border-left: 1px solid var(--line);
}

.page-about .flow-step::after {
  content: "";
  position: absolute;
  left: -1px;
  top: 0;
  width: 1px;
  height: 26px;
  background: var(--orange);
}

.page-about .flow-step__num {
  display: block;
  margin-bottom: 0.3rem;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  color: var(--muted);
}

.page-about .flow-step__title {
  margin: 0 0 0.35rem;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text);
}

.page-about .flow-step__text {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.8;
  color: var(--muted);
}

@media (min-width: 720px) {
  .page-about .flow-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: clamp(1.5rem, 4vw, 3rem);
    row-gap: 1.5rem;
  }
}

.page-about .sla-list {
  margin: 0;
  border-top: 1px solid var(--line-soft);
}

.page-about .sla-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.2rem;
  padding: 0.8rem 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .sla-row dt {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  line-height: 1.7;
  letter-spacing: 0.1em;
  color: var(--cyan-deep);
}

.page-about .sla-row dd {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.75;
  color: var(--text);
}

@media (min-width: 620px) {
  .page-about .sla-row {
    grid-template-columns: minmax(9rem, 0.8fr) minmax(0, 2fr);
    gap: 1rem;
    align-items: baseline;
  }
}

/* ── 结尾行动区 ─────────────────────────── */
.page-about .about-cta {
  position: relative;
  overflow: hidden;
  margin-top: clamp(1rem, 3vw, 2rem);
  padding: clamp(1.75rem, 4vw, 2.75rem);
  border: 1px solid rgba(18, 224, 200, 0.35);
  border-radius: var(--radius);
  background:
    radial-gradient(ellipse 90% 120% at 100% 0%, rgba(18, 224, 200, 0.14), transparent 62%),
    var(--panel);
}

.page-about .about-cta::before {
  content: "";
  position: absolute;
  right: 0;
  bottom: 0;
  width: 220px;
  height: 220px;
  pointer-events: none;
  background: radial-gradient(circle, rgba(255, 106, 31, 0.16), transparent 68%);
}

.page-about .about-cta__title {
  position: relative;
  margin: 0.35rem 0 0.6rem;
  font-family: var(--font-display);
  font-size: clamp(1.4rem, 3.6vw, 2.1rem);
  font-weight: 300;
  line-height: 1.22;
  color: var(--text);
  text-wrap: balance;
}

.page-about .about-cta__text {
  position: relative;
  margin: 0 0 1.25rem;
  max-width: 60ch;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-cta__actions {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
}
<<<END>>>