.page-about {
  --ab-rail: 200px;
  --ab-gap: clamp(28px, 4.5vw, 64px);
  background: var(--ink);
  color: var(--paper);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding: clamp(36px, 6vw, 76px) 0 clamp(52px, 8vw, 108px);
  border-bottom: 1px solid var(--line);
  background: var(--ink);
}

.page-about .about-hero__bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 62%;
  opacity: .3;
  z-index: -2;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image:
    linear-gradient(rgba(35, 38, 47, .55) 1px, transparent 1px),
    linear-gradient(90deg, rgba(35, 38, 47, .55) 1px, transparent 1px);
  background-size: 48px 48px;
  opacity: .55;
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    linear-gradient(180deg, rgba(11, 12, 16, .62) 0%, rgba(11, 12, 16, .84) 46%, var(--ink) 100%),
    linear-gradient(96deg, rgba(255, 106, 26, .12) 0%, transparent 42%),
    linear-gradient(276deg, rgba(46, 211, 255, .1) 0%, transparent 40%);
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
}

.page-about .about-hero__crumb {
  margin-bottom: clamp(28px, 5vw, 56px);
}

.page-about .about-hero__coord {
  margin: 0 0 14px;
  color: var(--muted);
  font-size: 13px;
  letter-spacing: .06em;
}

.page-about .about-hero__title {
  max-width: 17ch;
  margin: 0 0 20px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(36px, 7.4vw, 76px);
  line-height: 1.06;
  letter-spacing: -.01em;
  color: var(--paper);
  text-shadow: 0 0 1px var(--ink), 0 1px 0 rgba(255, 106, 26, .35);
}

.page-about .about-hero__lede {
  max-width: 62ch;
  margin: 0 0 clamp(26px, 4vw, 42px);
  font-size: clamp(16px, 2vw, 18px);
  line-height: 1.75;
  color: var(--paper-soft);
}

.page-about .about-hero__facts {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-hero__facts li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border: 1px solid var(--line);
  border-radius: var(--r-cap);
  background: rgba(20, 22, 28, .78);
  font-size: 13.5px;
  color: var(--paper-soft);
}

.page-about .about-hero__facts .mono {
  color: var(--orange);
  font-size: 14px;
  font-weight: 700;
}

/* ---------- 主体骨架 ---------- */
.page-about .about-flow {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--ab-gap);
  padding-top: clamp(40px, 6vw, 80px);
  padding-bottom: clamp(72px, 10vw, 140px);
}

/* ---------- 坐标轴 ---------- */
.page-about .about-rail {
  margin-inline: calc(var(--gutter) * -1);
  padding-inline: var(--gutter);
}

.page-about .about-rail ol {
  display: flex;
  gap: 10px;
  margin: 0;
  padding: 0 0 8px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
  scrollbar-color: var(--line) transparent;
}

.page-about .about-rail li {
  flex: 0 0 auto;
}

.page-about .about-rail a {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 8px 14px;
  border: 1px solid var(--line);
  border-radius: var(--r-cap);
  background: var(--surface);
  color: var(--muted);
  font-size: 13px;
  text-decoration: none;
  white-space: nowrap;
  transition: border-color .18s var(--ease), color .18s var(--ease), transform .18s var(--ease);
}

.page-about .about-rail a:hover,
.page-about .about-rail a:focus-visible {
  border-color: var(--orange);
  color: var(--paper);
  transform: translateY(-2px);
}

.page-about .about-rail .coord {
  color: var(--orange);
  font-size: 12px;
  letter-spacing: .04em;
}

/* ---------- 章节流 ---------- */
.page-about .about-stream {
  display: grid;
  gap: clamp(60px, 8vw, 112px);
  min-width: 0;
}

.page-about .about-sec {
  scroll-margin-top: 108px;
  min-width: 0;
}

.page-about .about-sec__num {
  display: block;
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: clamp(30px, 5vw, 50px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: .02em;
  color: var(--line);
  transition: color .5s var(--ease);
}

.page-about .about-sec__num.is-lit {
  color: var(--orange);
}

.page-about .about-sec .section__title {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(26px, 4.2vw, 40px);
  line-height: 1.16;
  color: var(--paper);
}

.page-about .about-sec .section__kicker {
  margin: 0 0 26px;
  font-size: 15px;
  color: var(--muted);
}

.page-about .about-sec .section__body {
  min-width: 0;
}

.page-about .about-sec .prose p {
  max-width: 68ch;
  margin: 0 0 18px;
  font-size: 16.5px;
  line-height: 1.78;
  color: var(--paper-soft);
}

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

.page-about .about-sec a {
  color: var(--blue);
  text-decoration: none;
  border-bottom: 1px solid rgba(46, 211, 255, .3);
  transition: border-color .18s var(--ease), color .18s var(--ease);
}

.page-about .about-sec a:hover,
.page-about .about-sec a:focus-visible {
  color: var(--orange-soft);
  border-bottom-color: var(--orange);
}

/* ---------- 三条业务线 ---------- */
.page-about .about-lines {
  align-items: start;
}

.page-about .about-line {
  position: relative;
  padding: 24px 22px 20px;
  min-height: 100%;
  transition: border-color .12s var(--ease), transform .12s var(--ease);
}

.page-about .about-line:hover {
  transform: translateY(-2px);
}

.page-about .about-line__idx {
  margin: 0 0 12px;
  font-size: 13px;
  letter-spacing: .14em;
  color: var(--orange);
}

.page-about .about-line h3 {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 20px;
  line-height: 1.3;
  color: var(--paper);
}

.page-about .about-line p {
  margin: 0 0 14px;
  font-size: 15px;
  line-height: 1.72;
  color: var(--paper-soft);
}

.page-about .about-line__foot {
  margin: 0;
  padding-top: 12px;
  border-top: 1px solid var(--line-soft);
  font-size: 12.5px;
  letter-spacing: .06em;
  color: var(--muted);
}

.page-about .about-lines__more {
  margin: 26px 0 0;
  max-width: 68ch;
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 版本时间线 ---------- */
.page-about .about-track {
  display: grid;
  gap: 0;
  margin: 0 0 38px;
  padding: 0;
  list-style: none;
}

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

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

.page-about .about-track a {
  display: grid;
  gap: 3px;
  text-decoration: none;
  border-bottom: 0;
}

.page-about .about-track__dot {
  position: absolute;
  left: -4px;
  top: 6px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--orange);
  box-shadow: 0 0 8px rgba(255, 106, 26, .75);
  transition: background .18s var(--ease), box-shadow .18s var(--ease);
}

.page-about .about-track a:hover .about-track__dot,
.page-about .about-track a:focus-visible .about-track__dot {
  background: var(--blue);
  box-shadow: 0 0 12px rgba(46, 211, 255, .85);
}

.page-about .about-track__ver {
  font-size: 12.5px;
  letter-spacing: .08em;
  color: var(--muted);
  text-transform: uppercase;
}

.page-about .about-track__name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 16px;
  line-height: 1.35;
  color: var(--paper);
  transition: color .18s var(--ease);
}

.page-about .about-track a:hover .about-track__name,
.page-about .about-track a:focus-visible .about-track__name {
  color: var(--orange-soft);
}

.page-about .about-vergrid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
}

.page-about .about-notes {
  display: grid;
  gap: 16px;
  min-width: 0;
}

.page-about .about-note {
  padding: 18px 20px;
  border: 1px solid var(--line);
  border-radius: 2px;
  background: var(--surface);
  scroll-margin-top: 110px;
  transition: border-color .18s var(--ease);
}

.page-about .about-note:hover {
  border-color: var(--orange);
}

.page-about .about-note__t {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .about-note__t .mono {
  font-size: 12.5px;
  color: var(--orange);
  letter-spacing: .1em;
}

.page-about .about-note p {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--paper-soft);
}

.page-about .about-verfig {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--surface);
}

.page-about .about-figcap {
  padding: 12px 14px;
  border-top: 1px solid var(--line-soft);
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 团队 ---------- */
.page-about .about-teamfig {
  margin: 0 0 30px;
  border: 1px solid var(--line);
  background: var(--surface);
}

.page-about .about-team {
  align-items: start;
}

.page-about .about-team__card {
  padding: 22px 20px;
  transition: border-color .12s var(--ease), transform .12s var(--ease);
}

.page-about .about-team__card:hover,
.page-about .about-team__card:focus-within {
  transform: translateY(-2px);
}

.page-about .about-team__name {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 19px;
  line-height: 1.3;
  color: var(--paper);
}

.page-about .about-team__line {
  margin: 0 0 14px;
  font-size: 13.5px;
  letter-spacing: .04em;
  color: var(--orange-soft);
}

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

.page-about .about-team__duty li {
  position: relative;
  padding-left: 16px;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--paper-soft);
}

.page-about .about-team__duty li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 1px;
  background: var(--blue);
}

.page-about .about-team__duty a {
  color: var(--blue);
  text-decoration: none;
  border-bottom: 1px solid rgba(46, 211, 255, .3);
}

/* ---------- 上架关卡 ---------- */
.page-about .about-gates {
  display: grid;
  gap: 14px;
  margin: 0 0 30px;
  padding: 0;
  list-style: none;
}

.page-about .about-gate {
  display: grid;
  gap: 8px;
  padding: 20px 22px;
  border-left: 2px solid var(--orange);
}

.page-about .about-gate__num {
  font-size: 12.5px;
  letter-spacing: .14em;
  color: var(--orange);
}

.page-about .about-gate h3 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 19px;
  color: var(--paper);
}

.page-about .about-gate p {
  margin: 0;
  max-width: 66ch;
  font-size: 15px;
  line-height: 1.74;
  color: var(--paper-soft);
}

.page-about .about-rule {
  margin: 0 0 30px;
}

.page-about .about-rules {
  align-items: start;
}

.page-about .about-rulecard {
  padding: 22px 20px;
}

.page-about .about-rulecard h3 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 17.5px;
  line-height: 1.35;
  color: var(--paper);
}

.page-about .about-rulecard p {
  margin: 0;
  font-size: 15px;
  line-height: 1.74;
  color: var(--paper-soft);
}

/* ---------- 数字 ---------- */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0 0 26px;
  padding: 0;
  list-style: none;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-stat {
  display: grid;
  gap: 8px;
  padding: 20px 18px;
  background: var(--surface);
}

.page-about .about-stat__num {
  font-size: clamp(26px, 4.6vw, 40px);
  font-weight: 700;
  line-height: 1;
  color: var(--orange);
  letter-spacing: -.01em;
}

.page-about .about-stat__label {
  font-size: 13.5px;
  line-height: 1.55;
  color: var(--muted);
}

.page-about .about-stats__note {
  max-width: 68ch;
  margin: 0;
  font-size: 15px;
  line-height: 1.76;
  color: var(--paper-soft);
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  position: relative;
  padding: clamp(30px, 5vw, 52px) clamp(22px, 4vw, 44px);
  border: 1px solid var(--line);
  border-left: 2px solid var(--orange);
  background:
    linear-gradient(120deg, rgba(255, 106, 26, .09) 0%, transparent 52%),
    linear-gradient(300deg, rgba(46, 211, 255, .08) 0%, transparent 48%),
    var(--surface);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--cut)), calc(100% - var(--cut)) 100%, 0 100%);
}

.page-about .about-cta__coord {
  margin: 0 0 14px;
  font-size: 12.5px;
  letter-spacing: .08em;
  color: var(--muted);
}

.page-about .about-cta__title {
  max-width: 22ch;
  margin: 0 0 16px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(24px, 4vw, 36px);
  line-height: 1.2;
  color: var(--paper);
}

.page-about .about-cta__text {
  max-width: 64ch;
  margin: 0 0 28px;
  font-size: 15.5px;
  line-height: 1.76;
  color: var(--paper-soft);
}

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

.page-about .about-cta__btn {
  transition: transform .12s var(--ease), border-color .18s var(--ease), background-color .18s var(--ease);
}

.page-about .about-cta__btn:hover,
.page-about .about-cta__btn:focus-visible {
  transform: translateY(-2px);
}

/* ---------- 平板 ---------- */
@media (min-width: 720px) {
  .page-about .about-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-vergrid {
    grid-template-columns: minmax(0, 1.45fr) minmax(0, 1fr);
    gap: 32px;
    align-items: start;
  }

  .page-about .about-verfig {
    position: sticky;
    top: 108px;
  }

  .page-about .about-team__card--b {
    margin-top: 24px;
  }

  .page-about .about-team__card--c {
    margin-top: -12px;
  }

  .page-about .about-team__card--d {
    margin-top: 12px;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 960px) {
  .page-about .about-flow {
    grid-template-columns: var(--ab-rail) minmax(0, 1fr);
    gap: clamp(36px, 5vw, 72px);
  }

  .page-about .about-rail {
    position: sticky;
    top: 108px;
    align-self: start;
    margin-inline: 0;
    padding: 4px 0 0 18px;
    border-left: 1px solid var(--line);
  }

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

  .page-about .about-rail li {
    flex: 1 1 auto;
  }

  .page-about .about-rail a {
    display: grid;
    grid-template-columns: 48px minmax(0, 1fr);
    align-items: baseline;
    gap: 10px;
    padding: 10px 0;
    border: 0;
    border-bottom: 1px solid var(--line-soft);
    border-radius: 0;
    background: none;
    white-space: normal;
    font-size: 13.5px;
    line-height: 1.5;
    transform: none;
  }

  .page-about .about-rail a:hover,
  .page-about .about-rail a:focus-visible {
    transform: none;
    color: var(--paper);
  }

  .page-about .about-rail a:hover .about-rail__name,
  .page-about .about-rail a:focus-visible .about-rail__name {
    color: var(--orange-soft);
  }

  .page-about .about-rail__name {
    transition: color .18s var(--ease);
  }

  .page-about .about-track {
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 0;
    margin-bottom: 44px;
  }

  .page-about .about-track li {
    padding: 26px 18px 0 0;
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .page-about .about-track li:first-child {
    border-top-color: var(--orange);
  }

  .page-about .about-track li:last-child {
    border-top-color: var(--blue);
    padding-bottom: 0;
  }

  .page-about .about-track__dot {
    left: 0;
    top: -4px;
  }

  .page-about .about-track__name {
    font-size: 15px;
  }

  .page-about .about-note {
    padding: 20px 22px;
  }
}

@media (min-width: 1100px) {
  .page-about .about-rail {
    padding-left: 22px;
  }

  .page-about .about-note:nth-child(even) {
    margin-left: 26px;
  }
}

/* ---------- hover 展开职责 ---------- */
@media (hover: hover) and (pointer: fine) {
  .page-about .about-team__duty {
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transition: max-height .32s var(--ease), opacity .22s var(--ease);
  }

  .page-about .about-team__card:hover .about-team__duty,
  .page-about .about-team__card:focus-within .about-team__duty {
    max-height: 260px;
    opacity: 1;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail a,
  .page-about .about-line,
  .page-about .about-team__card,
  .page-about .about-cta__btn {
    transition: color .18s linear, border-color .18s linear, background-color .18s linear;
  }

  .page-about .about-rail a:hover,
  .page-about .about-line:hover,
  .page-about .about-team__card:hover,
  .page-about .about-cta__btn:hover {
    transform: none;
  }
}
<<<END>>>