.page-about {
  --about-gap: 22px;
  --about-pad: 18px;
  display: block;
  color: var(--text);
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumbs {
  padding: 20px 0 4px;
  font-size: 13px;
  color: var(--muted);
}
.page-about .breadcrumbs ol {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  letter-spacing: .02em;
}
.page-about .breadcrumbs li {
  display: flex;
  align-items: center;
  gap: 8px;
}
.page-about .breadcrumbs li + li::before {
  content: "/";
  color: var(--line);
}
.page-about .breadcrumbs a {
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .2s ease, border-color .2s ease;
}
.page-about .breadcrumbs a:hover,
.page-about .breadcrumbs a:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan-dim);
}
.page-about .breadcrumbs [aria-current="page"] {
  color: var(--text);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: 28px;
  padding: 26px 0 8px;
}
.page-about .about-kicker {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--cyan-dim);
}
.page-about .about-hero h1 {
  margin: 0 0 18px;
  font-size: clamp(34px, 8vw, 56px);
  font-weight: 900;
  line-height: 1.06;
  letter-spacing: -.02em;
}
.page-about .about-hero h1::after {
  content: "";
  display: block;
  width: 74px;
  height: 3px;
  margin-top: 18px;
  background: linear-gradient(90deg, var(--cyan) 0%, var(--violet) 100%);
}
.page-about .about-hero__lede {
  margin: 0 0 24px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--text);
  max-width: 46em;
}
.page-about .about-hero__facts {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.page-about .about-hero__facts li {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 8px 14px;
  border: 1px solid var(--line);
  background: var(--ink-card);
  font-size: 12px;
  color: var(--muted);
}
.page-about .about-hero__facts b {
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 700;
  color: var(--gold);
  line-height: 1;
}
.page-about .about-hero__media {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--ink-card);
  overflow: hidden;
  position: relative;
}
.page-about .about-hero__media img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
  aspect-ratio: 3 / 2;
  filter: saturate(.85) contrast(1.05);
}
.page-about .about-hero__media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(155deg, rgba(56, 225, 200, .14) 0%, rgba(5, 16, 13, .55) 62%, rgba(5, 16, 13, .82) 100%);
  pointer-events: none;
}

/* ---------- 章节速览 ---------- */
.page-about .chapter-preview {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 34px 0 8px;
  padding: 16px 0 20px;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.page-about .chapter-chip {
  flex: 1 1 140px;
  display: flex;
  align-items: baseline;
  gap: 9px;
  padding: 10px 12px;
  border: 1px solid var(--line);
  background: transparent;
  text-decoration: none;
  color: var(--muted);
  transition: border-color .22s ease, background-color .22s ease, color .22s ease, transform .22s ease;
}
.page-about .chapter-chip:hover,
.page-about .chapter-chip:focus-visible {
  border-color: var(--cyan);
  background: var(--ink-card);
  color: var(--text);
  transform: translateY(-3px);
}
.page-about .chapter-chip__num {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--cyan);
}
.page-about .chapter-chip__label {
  font-size: 13px;
}

/* ---------- 章节骨架 ---------- */
.page-about .about-chapter {
  padding: 52px 0 8px;
  position: relative;
}
.page-about .about-chapter + .about-chapter {
  margin-top: 12px;
  border-top: 1px solid var(--line);
}
.page-about .about-chapter .section-head {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 16px;
}
.page-about .about-chapter .section-index {
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  color: var(--cyan);
  line-height: 1;
  letter-spacing: -.02em;
}
.page-about .about-chapter .section-title {
  margin: 0;
  font-size: clamp(22px, 5vw, 28px);
  font-weight: 800;
  letter-spacing: -.01em;
}
.page-about .about-chapter .section-note {
  writing-mode: vertical-rl;
  font-size: 12px;
  letter-spacing: .3em;
  color: var(--muted);
  align-self: start;
}
.page-about .about-lede {
  margin: 0 0 26px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--text);
  max-width: 54em;
  padding-left: 14px;
  border-left: 2px solid var(--cyan-dim);
}

/* ---------- 01 三条业务线 ---------- */
.page-about .line-grid {
  display: grid;
  gap: var(--about-gap);
}
.page-about .line-card {
  position: relative;
  padding: 22px 20px 20px;
  background: var(--ink-card);
  border: 1px solid var(--line);
  transition: transform .28s ease, border-color .28s ease, background-color .28s ease;
}
.page-about .line-card:hover {
  transform: translateY(-4px);
  border-color: var(--cyan);
  background: var(--ink-lift);
}
.page-about .line-card__badge {
  position: absolute;
  top: -11px;
  left: 18px;
  padding: 3px 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--deep);
  background: var(--cyan);
}
.page-about .line-card:nth-child(2) .line-card__badge {
  background: var(--gold);
}
.page-about .line-card:nth-child(3) .line-card__badge {
  color: var(--text);
  background: var(--ink-lift);
  border: 1px solid var(--violet);
}
.page-about .line-card__title {
  margin: 8px 0 12px;
  font-size: 19px;
  font-weight: 800;
}
.page-about .line-card__text {
  margin: 0 0 16px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--text);
}
.page-about .line-card__text a,
.page-about .practice-tail a,
.page-about .team-fold__body a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid var(--cyan-dim);
  transition: color .2s ease, border-color .2s ease;
}
.page-about .line-card__text a:hover,
.page-about .practice-tail a:hover,
.page-about .team-fold__body a:hover {
  color: var(--gold-soft);
  border-bottom-color: var(--gold);
}
.page-about .line-card__meta {
  margin: 0;
  padding: 12px 0 0;
  list-style: none;
  border-top: 1px dashed var(--line);
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--muted);
}
.page-about .line-card__meta li::before {
  content: "▸ ";
  color: var(--cyan-dim);
}

/* ---------- 02 团队折叠 ---------- */
.page-about .team-fold {
  display: grid;
  gap: 12px;
}
.page-about .team-fold__item {
  background: var(--ink-card);
  border: 1px solid var(--line);
  transition: border-color .24s ease;
}
.page-about .team-fold__item[open] {
  border-color: var(--cyan-dim);
  background: var(--ink-lift);
}
.page-about .team-fold__sum {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
  font-size: 17px;
  font-weight: 700;
}
.page-about .team-fold__sum::-webkit-details-marker {
  display: none;
}
.page-about .team-fold__sum::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--cyan);
  margin-left: auto;
}
.page-about .team-fold__item[open] .team-fold__sum::after {
  content: "–";
  color: var(--gold);
}
.page-about .team-fold__role {
  flex: 0 0 auto;
}
.page-about .team-fold__count {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--gold);
  padding: 3px 9px;
  border: 1px solid var(--line);
  background: var(--ink-bg);
}
.page-about .team-fold__body {
  padding: 0 18px 18px;
}
.page-about .team-fold__body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--text);
}

/* ---------- 03 流程 ---------- */
.page-about .flow-wrap {
  display: grid;
  gap: 26px;
}
.page-about .flow-steps {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: flow;
  display: grid;
  gap: 0;
}
.page-about .flow-step {
  position: relative;
  padding: 0 0 22px 54px;
}
.page-about .flow-step:last-child {
  padding-bottom: 0;
}
.page-about .flow-step::before {
  content: "";
  position: absolute;
  left: 19px;
  top: 26px;
  bottom: -2px;
  width: 1px;
  background: var(--line);
}
.page-about .flow-step:last-child::before {
  display: none;
}
.page-about .flow-step__idx {
  position: absolute;
  left: 0;
  top: 0;
  width: 40px;
  height: 40px;
  display: grid;
  place-items: center;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--cyan);
  border: 1px solid var(--line);
  background: var(--ink-card);
  transition: color .24s ease, border-color .24s ease, background-color .24s ease;
}
.page-about .flow-step:hover .flow-step__idx {
  color: var(--deep);
  background: var(--cyan);
  border-color: var(--cyan);
}
.page-about .flow-step__name {
  margin: 8px 0 8px;
  font-size: 17px;
  font-weight: 800;
}
.page-about .flow-step__desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--muted);
}
.page-about .flow-step:hover .flow-step__desc {
  color: var(--text);
}
.page-about .flow-figure {
  margin: 0;
  border: 1px solid var(--line);
  background: linear-gradient(160deg, var(--ink-lift) 0%, var(--ink-bg) 100%);
  position: relative;
  overflow: hidden;
}
.page-about .flow-figure img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
  aspect-ratio: 1 / 1;
  opacity: .82;
}
.page-about .flow-figure::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 30% 25%, rgba(56, 225, 200, .16) 0%, transparent 58%);
  pointer-events: none;
}

/* ---------- 04 时间轴 ---------- */
.page-about .timeline {
  margin: 0;
  padding: 0 0 0 30px;
  list-style: none;
  position: relative;
}
.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan) 0%, var(--line) 55%, transparent 100%);
}
.page-about .timeline-item {
  position: relative;
  padding: 0 0 28px;
}
.page-about .timeline-item:last-child {
  padding-bottom: 0;
}
.page-about .timeline-item::before {
  content: "";
  position: absolute;
  left: -30px;
  top: 6px;
  width: 11px;
  height: 11px;
  background: var(--ink-bg);
  border: 1px solid var(--cyan-dim);
  transform: rotate(45deg);
  transition: border-color .24s ease, box-shadow .24s ease, background-color .24s ease;
}
.page-about .timeline-item:hover::before {
  border-color: var(--cyan);
  background: var(--cyan);
  box-shadow: 0 0 0 5px rgba(56, 225, 200, .12);
}
.page-about .timeline-item__stage {
  margin: 0 0 8px;
  font-size: 18px;
  font-weight: 800;
  letter-spacing: -.01em;
}
.page-about .timeline-item:hover .timeline-item__stage {
  color: var(--gold-soft);
}
.page-about .timeline-item__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--muted);
  max-width: 60em;
}

/* ---------- 05 覆盖与协作 ---------- */
.page-about .cover-grid {
  display: grid;
  gap: 24px;
}
.page-about .cover-figure {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--ink-card);
  overflow: hidden;
  position: relative;
}
.page-about .cover-figure img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
  aspect-ratio: 10 / 7;
  opacity: .9;
}
.page-about .cover-figure::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(200deg, rgba(233, 185, 73, .10) 0%, rgba(5, 16, 13, .6) 70%);
  pointer-events: none;
}
.page-about .cover-copy p {
  margin: 0 0 16px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--text);
}
.page-about .cover-stats {
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}
.page-about .cover-stat {
  position: relative;
  padding: 14px 12px 12px;
  border: 1px solid var(--line);
  background: var(--ink-card);
  cursor: default;
  transition: border-color .24s ease, background-color .24s ease, transform .24s ease;
}
.page-about .cover-stat:hover,
.page-about .cover-stat:focus-within {
  border-color: var(--cyan);
  background: var(--ink-lift);
  transform: translateY(-3px);
}
.page-about .cover-stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  line-height: 1;
  color: var(--gold);
  letter-spacing: -.03em;
}
.page-about .cover-stat__label {
  display: block;
  margin-top: 8px;
  font-size: 12px;
  color: var(--muted);
  letter-spacing: .04em;
}
.page-about .cover-stat__pop {
  position: absolute;
  left: -1px;
  right: -1px;
  bottom: calc(100% + 6px);
  padding: 10px 12px;
  font-size: 12px;
  line-height: 1.7;
  color: var(--deep);
  background: var(--cyan);
  opacity: 0;
  visibility: hidden;
  transform: translateY(6px);
  transition: opacity .22s ease, transform .22s ease, visibility .22s ease;
  z-index: 3;
}
.page-about .cover-stat:hover .cover-stat__pop,
.page-about .cover-stat:focus-within .cover-stat__pop {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

/* ---------- 06 做法 ---------- */
.page-about .practice-list {
  display: grid;
  gap: 14px;
}
.page-about .practice-item {
  position: relative;
  padding: 20px 20px 20px 22px;
  background: var(--ink-card);
  border: 1px solid var(--line);
  border-left: 3px solid var(--cyan-dim);
  transition: border-left-color .24s ease, background-color .24s ease, transform .24s ease;
}
.page-about .practice-item:hover {
  border-left-color: var(--gold);
  background: var(--ink-lift);
  transform: translateX(3px);
}
.page-about .practice-item h3 {
  margin: 10px 0 10px;
  font-size: 18px;
  font-weight: 800;
}
.page-about .practice-item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--muted);
}
.page-about .practice-item:hover p {
  color: var(--text);
}
.page-about .practice-tail {
  margin: 26px 0 0;
  padding: 18px 20px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--text);
  background: linear-gradient(100deg, rgba(56, 225, 200, .12) 0%, rgba(139, 92, 246, .10) 100%);
  border: 1px solid var(--line);
}

/* ---------- 宽屏 ---------- */
@media (min-width: 760px) {
  .page-about {
    --about-gap: 26px;
  }
  .page-about .line-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    align-items: start;
    padding-top: 14px;
  }
  .page-about .line-card:nth-child(2) {
    margin-top: 30px;
  }
  .page-about .line-card:nth-child(3) {
    margin-top: 12px;
  }

  .page-about .team-fold {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
  }

  .page-about .flow-wrap {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
    align-items: start;
    gap: 34px;
  }
  .page-about .flow-figure {
    position: sticky;
    top: calc(var(--header-h) + 20px);
  }

  .page-about .cover-grid {
    grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr);
    align-items: start;
    gap: 30px;
  }
  .page-about .cover-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 12px;
  }
  .page-about .cover-stat__num {
    font-size: 34px;
  }

  .page-about .practice-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }
}

@media (min-width: 1020px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
    align-items: end;
    gap: 44px;
    padding-top: 34px;
  }
  .page-about .about-hero__lede {
    font-size: 17px;
  }
  .page-about .about-hero__media {
    margin-bottom: 6px;
  }
  .page-about .about-hero__media img {
    aspect-ratio: 4 / 3;
  }

  .page-about .about-chapter {
    padding-top: 68px;
    padding-left: 58px;
  }
  .page-about .about-chapter .section-index {
    font-size: 44px;
  }
  .page-about .about-chapter .section-head {
    gap: 18px;
    margin-bottom: 20px;
  }
  .page-about .about-chapter .section-note {
    font-size: 13px;
  }

  .page-about .chapter-preview {
    gap: 12px;
  }
  .page-about .chapter-chip {
    flex: 1 1 0;
  }

  .page-about .practice-item {
    padding: 24px 24px 24px 26px;
  }
}
<<<END>>>