.page-about {
  --about-ink-soft: #46585f;
  --about-rail-w: 200px;
  --about-gutter: clamp(24px, 4vw, 56px);
  --about-pad-x: clamp(18px, 3.4vw, 40px);
  --about-cyan-soft: rgba(43, 227, 198, .16);
  background: var(--ink-900);
  color: var(--paper);
}

/* ---------- 首屏框景 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(28px, 5vw, 62px) var(--about-pad-x) clamp(38px, 5vw, 70px);
  background:
    radial-gradient(120% 100% at 8% 0%, rgba(43, 227, 198, .11), transparent 58%),
    radial-gradient(90% 80% at 100% 8%, rgba(255, 106, 43, .10), transparent 62%),
    linear-gradient(180deg, #082234 0%, var(--ink-900) 100%);
  border-bottom: 1px solid var(--line-dark);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--grid-dark) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-dark) 1px, transparent 1px);
  background-size: 52px 52px;
  -webkit-mask-image: radial-gradient(90% 72% at 22% 8%, #000 18%, transparent 82%);
  mask-image: radial-gradient(90% 72% at 22% 8%, #000 18%, transparent 82%);
  pointer-events: none;
}

.page-about .about-hero__frame {
  position: relative;
  z-index: 1;
  padding: clamp(22px, 2.8vw, 38px);
  border: 1px solid var(--line-dark);
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(7, 26, 43, .62), rgba(7, 26, 43, .12));
  box-shadow: var(--shadow-1);
}

.page-about .about-hero__frame::after {
  content: "";
  position: absolute;
  left: clamp(22px, 2.8vw, 38px);
  right: clamp(22px, 2.8vw, 38px);
  top: 0;
  height: 9px;
  background-image: repeating-linear-gradient(90deg, var(--line-dark) 0 1px, transparent 1px 26px);
  pointer-events: none;
}

.page-about .about-hero__crumb,
.page-about .about-hero__crumb * {
  color: var(--steel);
}

.page-about .about-hero__crumb {
  margin-bottom: clamp(20px, 2.6vw, 30px);
}

.page-about .about-hero__crumb .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 13px;
  letter-spacing: .06em;
}

.page-about .about-hero__crumb a {
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

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

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

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-family: var(--font-head);
  font-size: clamp(30px, 5.4vw, 56px);
  font-weight: 800;
  line-height: 1.14;
  letter-spacing: -.01em;
  color: var(--white);
  max-width: 18em;
}

.page-about .about-hero__lead {
  margin: clamp(16px, 2.4vw, 24px) 0 0;
  font-size: 15.5px;
  line-height: 1.95;
  color: #c7d6e2;
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: clamp(26px, 3.6vw, 42px);
  background: var(--line-dark-soft);
  border: 1px solid var(--line-dark-soft);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-hero__stat {
  display: block;
  padding: 16px 18px;
  background: rgba(6, 22, 36, .78);
}

.page-about .about-hero__stat .stat__value {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(21px, 3vw, 30px);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: .01em;
  color: var(--cyan);
}

.page-about .about-hero__stat .stat__label {
  display: block;
  margin-top: 7px;
  font-size: 12.5px;
  letter-spacing: .08em;
  color: var(--steel);
}

.page-about .about-hero__cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(24px, 3vw, 36px);
}

/* ---------- 主体：纸面 + 左侧刻度索引 ---------- */
.page-about .about-body {
  background: var(--paper);
  color: var(--graphite);
}

.page-about .about-body__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gutter);
  padding-top: clamp(30px, 5vw, 62px);
  padding-bottom: clamp(48px, 7vw, 96px);
}

.page-about .about-rail {
  border-bottom: 1px solid var(--line-light);
  padding-bottom: 14px;
}

.page-about .about-rail__title {
  margin: 0 0 12px;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .18em;
  color: var(--about-ink-soft);
  text-transform: uppercase;
}

.page-about .about-rail__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .about-rail__item {
  flex: 0 0 auto;
}

.page-about .about-rail__link {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: 1px solid var(--line-light);
  border-radius: var(--radius);
  font-size: 13.5px;
  color: var(--about-ink-soft);
  text-decoration: none;
  white-space: nowrap;
  transition: color .2s ease, border-color .2s ease, background-color .2s ease;
}

.page-about .about-rail__idx {
  font-size: 11.5px;
  color: var(--lava-ink);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--graphite);
  border-color: var(--cyan);
  background: rgba(43, 227, 198, .10);
}

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

.page-about .about-sec {
  padding-top: clamp(36px, 5vw, 62px);
  scroll-margin-top: calc(var(--header-h) + 24px);
}

.page-about .about-flow > .about-sec:first-child {
  padding-top: 0;
}

.page-about .about-sec + .about-sec {
  border-top: 1px solid var(--line-light);
}

.page-about .about-sec__head {
  display: flex;
  align-items: flex-start;
  gap: clamp(12px, 2vw, 20px);
  margin-bottom: clamp(16px, 2.4vw, 26px);
}

.page-about .about-sec__idx {
  flex: 0 0 auto;
  padding-top: .5em;
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: .08em;
  color: var(--lava);
}

.page-about .about-sec__title {
  margin: 0;
  font-family: var(--font-head);
  font-size: clamp(22px, 3.2vw, 34px);
  font-weight: 800;
  line-height: 1.3;
  letter-spacing: -.005em;
  color: var(--graphite);
}

.page-about .about-flow p {
  max-width: 720px;
  margin: 0 0 16px;
  font-size: 15px;
  line-height: 1.9;
  color: var(--about-ink-soft);
}

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

.page-about .about-lede {
  font-size: 16.5px !important;
  line-height: 1.9;
  color: var(--graphite) !important;
}

.page-about .about-note {
  margin-top: clamp(20px, 2.6vw, 28px);
  padding-left: 14px;
  border-left: 2px solid var(--amber);
  font-size: 14px !important;
}

.page-about .about-flow a {
  color: var(--lava-ink);
  text-decoration: underline;
  text-decoration-color: rgba(194, 65, 12, .38);
  text-underline-offset: 3px;
}

.page-about .about-flow a:hover {
  text-decoration-color: var(--lava);
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 0 0 clamp(22px, 3vw, 32px);
  max-width: 860px;
}

.page-about .about-figure--wide {
  max-width: 920px;
}

.page-about .about-figure--narrow {
  max-width: 620px;
}

.page-about .about-figure__frame {
  position: relative;
  border: 1px solid var(--line-light);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--ink-800);
  box-shadow: 0 14px 30px -26px rgba(7, 26, 43, .9);
}

.page-about .about-figure__frame::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 8px;
  background-image: repeating-linear-gradient(90deg, rgba(244, 239, 230, .34) 0 1px, transparent 1px 24px);
  pointer-events: none;
  z-index: 1;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
}

.page-about .about-figure__cap {
  margin-top: 10px;
  font-size: 12.5px;
  letter-spacing: .05em;
  line-height: 1.7;
  color: var(--about-ink-soft);
}

/* ---------- 深色数据条 ---------- */
.page-about .about-bar {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(22px, 3vw, 34px) 0;
  background: rgba(108, 139, 163, .3);
  border-radius: var(--radius);
  overflow: hidden;
  max-width: 860px;
}

.page-about .about-bar__cell {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 18px 16px;
  background: var(--ink-800);
}

.page-about .about-bar__num {
  font-size: clamp(17px, 2.2vw, 23px);
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--cyan);
}

.page-about .about-bar__txt {
  font-size: 12px;
  letter-spacing: .07em;
  color: var(--steel);
}

/* ---------- 三条服务线 ---------- */
.page-about .about-lines {
  display: grid;
  gap: 1px;
  margin-top: clamp(22px, 3vw, 30px);
  background: var(--line-light);
  border-top: 1px solid var(--line-light);
  border-bottom: 1px solid var(--line-light);
}

.page-about .about-line {
  display: grid;
  gap: 12px;
  padding: clamp(20px, 2.6vw, 28px) 0;
  background: var(--paper);
}

.page-about .about-line__name {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-size: 17px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--graphite);
}

.page-about .about-line__body p {
  margin: 0;
}

/* ---------- 团队角色表 ---------- */
.page-about .about-roles {
  list-style: none;
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line-light);
  border-top: 1px solid var(--line-light);
  border-bottom: 1px solid var(--line-light);
}

.page-about .about-roles__item {
  display: grid;
  grid-template-columns: 60px minmax(0, 1fr);
  align-items: baseline;
  column-gap: 14px;
  row-gap: 8px;
  padding: 20px 0;
  background: var(--paper);
}

.page-about .about-roles__num {
  font-size: 24px;
  font-weight: 700;
  line-height: 1;
  color: var(--lava);
}

.page-about .about-roles__name {
  margin: 0;
  align-self: center;
  font-size: 16.5px;
  font-weight: 700;
  color: var(--graphite);
}

.page-about .about-roles__desc {
  grid-column: 2;
  margin: 0;
  max-width: 640px;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--about-ink-soft);
}

/* ---------- 里程碑时间轴 ---------- */
.page-about .about-timeline {
  --tl-pad: clamp(24px, 3vw, 36px);
  position: relative;
  list-style: none;
  margin: clamp(22px, 3vw, 30px) 0 0;
  padding: 0;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 6px;
  bottom: 6px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan), rgba(43, 227, 198, .12));
}

.page-about .about-timeline__item {
  position: relative;
  padding: 0 0 clamp(24px, 3vw, 34px) var(--tl-pad);
}

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

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: 1px;
  top: 6px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 3px var(--about-cyan-soft);
}

.page-about .about-timeline__year {
  display: inline-block;
  margin-bottom: 6px;
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--lava-ink);
}

.page-about .about-timeline__title {
  margin: 0 0 6px;
  font-family: var(--font-head);
  font-size: 17px;
  font-weight: 700;
  color: var(--graphite);
}

.page-about .about-timeline__item p {
  margin: 0;
}

/* ---------- 服务承诺 ---------- */
.page-about .about-promise {
  margin: clamp(20px, 2.8vw, 30px) 0 0;
  padding: 0;
  border-top: 1px solid var(--line-light);
}

.page-about .about-promise__row {
  display: grid;
  gap: 6px;
  padding: 18px 0;
  border-bottom: 1px solid var(--line-light);
}

.page-about .about-promise__key {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--lava-ink);
}

.page-about .about-promise__val {
  margin: 0;
  max-width: 700px;
  font-size: 15px;
  line-height: 1.9;
  color: var(--about-ink-soft);
}

.page-about .about-links {
  display: grid;
  gap: 1px;
  margin-top: clamp(24px, 3vw, 34px);
  background: var(--line-light);
  border: 1px solid var(--line-light);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-links__item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 18px;
  background: var(--paper-2);
  color: var(--graphite) !important;
  text-decoration: none !important;
  font-size: 14.5px;
  font-weight: 600;
  transition: background-color .2s ease, color .2s ease;
}

.page-about .about-links__item:hover,
.page-about .about-links__item:focus-visible {
  background: var(--ink-800);
  color: var(--white) !important;
}

.page-about .about-links__arrow {
  font-family: var(--font-mono);
  color: var(--lava);
}

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

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-promise__row {
    grid-template-columns: 180px minmax(0, 1fr);
    align-items: baseline;
    column-gap: 24px;
  }
}

@media (min-width: 760px) {
  .page-about .about-line {
    grid-template-columns: 170px minmax(0, 1fr);
    align-items: start;
    column-gap: clamp(20px, 3vw, 36px);
    padding: clamp(22px, 2.8vw, 30px) 0;
  }
}

@media (min-width: 900px) {
  .page-about .about-body__inner {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 28px);
    align-self: start;
    max-height: calc(100vh - var(--header-h) - 56px);
    border-bottom: 0;
    padding-bottom: 0;
    overflow-y: auto;
  }

  .page-about .about-rail__title {
    margin-bottom: 16px;
  }

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

  .page-about .about-rail__item {
    flex: 1 1 auto;
  }

  .page-about .about-rail__link {
    width: 100%;
    border: 0;
    border-left: 1px solid var(--line-light);
    border-radius: 0;
    padding: 12px 0 12px 18px;
    white-space: normal;
    line-height: 1.5;
    background: transparent;
  }

  .page-about .about-rail__link::before {
    content: "";
    position: absolute;
    left: -1px;
    top: 50%;
    width: 2px;
    height: 0;
    background: var(--cyan);
    transform: translateY(-50%);
    transition: height .24s ease;
  }

  .page-about .about-rail__link:hover::before,
  .page-about .about-rail__link:focus-visible::before {
    height: 100%;
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    background: transparent;
    border-color: var(--line-light);
    color: var(--graphite);
  }
}

@media (min-width: 1180px) {
  .page-about {
    --about-rail-w: 216px;
  }

  .page-about .about-figure--wide {
    max-width: 920px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .about-rail__link::before,
  .page-about .about-links__item {
    transition: none;
  }
}
<<<END>>>