.page-about {
  background: var(--ink);
  color: var(--paper);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-about .about-masthead {
  position: relative;
  padding: clamp(2.25rem, 6vw, 4.25rem) 0 clamp(2.5rem, 7vw, 4.5rem);
  border-bottom: 1px solid var(--line);
  background:
    repeating-linear-gradient(90deg, rgba(200, 164, 92, 0.055) 0 1px, transparent 1px 64px),
    radial-gradient(115% 95% at 8% -10%, rgba(200, 164, 92, 0.12), transparent 58%),
    var(--ink);
}

.page-about .about-masthead::after {
  content: "";
  position: absolute;
  inset: 0 0 0 auto;
  width: min(48vw, 430px);
  background: linear-gradient(205deg, rgba(94, 122, 138, 0.22), transparent 62%);
  pointer-events: none;
}

.page-about .about-masthead__inner {
  position: relative;
  z-index: 1;
}

.page-about .about-masthead__eyebrow {
  color: var(--gold);
  letter-spacing: 0.16em;
}

.page-about .about-masthead__title {
  margin: 0.7rem 0 0;
  max-width: 20ch;
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: clamp(2.15rem, 7vw, 4.4rem);
  line-height: 1.1;
  letter-spacing: -0.015em;
  color: var(--paper);
}

.page-about .about-masthead__title em {
  font-style: normal;
  color: var(--gold-bright);
}

.page-about .about-masthead__lead {
  margin: clamp(1.1rem, 3vw, 1.6rem) 0 0;
  max-width: 60ch;
  font-size: clamp(0.95rem, 1.7vw, 1.0625rem);
  line-height: 1.85;
  color: rgba(244, 239, 228, 0.78);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.35rem 1.5rem;
  margin: clamp(1.75rem, 4vw, 2.75rem) 0 0;
  padding: 0;
  list-style: none;
}

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

.page-about .about-fact__num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: clamp(1.5rem, 3.6vw, 2.1rem);
  line-height: 1.1;
  letter-spacing: 0.01em;
  color: var(--gold-bright);
}

.page-about .about-fact__label {
  display: block;
  margin-top: 0.4rem;
  font-size: 0.8125rem;
  line-height: 1.5;
  color: var(--archive);
}

/* ---------- 主体骨架 ---------- */
.page-about .about-body {
  padding: clamp(2rem, 5vw, 3.5rem) 0 clamp(3rem, 7vw, 5rem);
}

.page-about .about-body__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 2rem;
}

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

/* ---------- 左侧编号栏 ---------- */
.page-about .about-index {
  display: none;
}

.page-about .about-index__title {
  margin: 0 0 0.9rem;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.18em;
  color: var(--archive);
}

.page-about .about-index__list {
  margin: 0;
  padding: 0;
  list-style: none;
  border-left: 1px solid var(--line-soft);
}

.page-about .about-index__link {
  display: grid;
  grid-template-columns: 2rem minmax(0, 1fr);
  align-items: baseline;
  gap: 0.4rem;
  margin-left: -1px;
  padding: 0.62rem 0.5rem 0.62rem 0.9rem;
  border-left: 2px solid transparent;
  color: rgba(244, 239, 228, 0.72);
  text-decoration: none;
  font-size: 0.875rem;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease),
    background-color var(--dur) var(--ease);
}

.page-about .about-index__num {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  border-left-color: var(--gold);
  background-color: rgba(200, 164, 92, 0.08);
  color: var(--paper);
}

.page-about .about-index__link:focus-visible {
  outline: 2px solid var(--gold-bright);
  outline-offset: 2px;
}

/* ---------- 章节 ---------- */
.page-about .about-chapter {
  padding: clamp(1.75rem, 4.5vw, 2.75rem) 0;
  border-top: 1px solid var(--line-soft);
  scroll-margin-top: 1.5rem;
}

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

.page-about .about-chapter__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: start;
  gap: 0.65rem 0.85rem;
  margin-bottom: 1.15rem;
}

.page-about .about-chapter__num {
  margin-top: 0.35rem;
  padding: 0.12rem 0.4rem;
  border: 1px solid var(--line-strong);
  color: var(--gold);
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
}

.page-about .about-chapter .section__title {
  margin: 0;
  font-size: clamp(1.35rem, 3.2vw, 1.85rem);
  line-height: 1.28;
  color: var(--paper);
}

.page-about .about-chapter .section__lead {
  margin: 0 0 1.5rem;
  max-width: 62ch;
  font-size: 1rem;
  line-height: 1.85;
  color: rgba(244, 239, 228, 0.74);
}

.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.5rem;
}

.page-about .about-split__text p {
  margin: 0 0 1rem;
  max-width: 66ch;
  font-size: 1rem;
  line-height: 1.85;
  color: rgba(244, 239, 228, 0.86);
}

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

.page-about .about-figure {
  margin: 0;
}

.page-about .about-figure--inline,
.page-about .about-figure--band {
  margin-top: 1.75rem;
}

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

.page-about .about-figure .media-figure__caption {
  display: block;
  margin-top: 0.7rem;
  padding-left: 0.8rem;
  border-left: 2px solid var(--slate);
  font-size: 0.8125rem;
  line-height: 1.65;
  color: var(--archive);
}

.page-about .about-note {
  margin: 1.35rem 0 0;
  padding: 0.85rem 1rem;
  border-left: 2px solid var(--gold);
  background: rgba(200, 164, 92, 0.06);
  font-size: 0.9375rem;
  line-height: 1.75;
  color: rgba(244, 239, 228, 0.82);
}

/* ---------- 职责折叠卡 ---------- */
.page-about .role-list {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  border: 1px solid var(--line-soft);
  background: var(--line-soft);
}

.page-about .role {
  background: var(--ink-2);
}

.page-about .role__summary {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto auto;
  align-items: center;
  gap: 0.7rem;
  padding: 1rem 1.1rem;
  cursor: pointer;
  list-style: none;
  transition: background-color var(--dur) var(--ease);
}

.page-about .role__summary::-webkit-details-marker {
  display: none;
}

.page-about .role__summary:hover {
  background: rgba(200, 164, 92, 0.07);
}

.page-about .role__summary:focus-visible {
  outline: 2px solid var(--gold-bright);
  outline-offset: -2px;
}

.page-about .role__name {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--paper);
}

.page-about .role__meta {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.1em;
  color: var(--slate);
}

.page-about .role__mark {
  position: relative;
  justify-self: end;
  width: 1rem;
  height: 1rem;
  flex: none;
}

.page-about .role__mark::before,
.page-about .role__mark::after {
  content: "";
  position: absolute;
  inset: 50% 0 auto 0;
  height: 1px;
  background: var(--gold);
  transition: transform var(--dur) var(--ease);
}

.page-about .role__mark::after {
  transform: rotate(90deg);
}

.page-about .role[open] .role__mark::after,
.page-about .timeline__node[open] .role__mark::after {
  transform: rotate(0deg);
}

.page-about .role__body {
  padding: 0 1.1rem 1.15rem;
  border-top: 1px solid var(--line-soft);
}

.page-about .role__body p {
  margin: 0.9rem 0 0.75rem;
  max-width: 64ch;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: rgba(244, 239, 228, 0.82);
}

.page-about .role__body ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .role__body li {
  position: relative;
  padding-left: 1.05rem;
  margin-bottom: 0.45rem;
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--archive);
}

.page-about .role__body li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.68em;
  width: 0.4rem;
  height: 1px;
  background: var(--gold);
}

/* ---------- 审校步骤 ---------- */
.page-about .review-steps {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
}

.page-about .review-step {
  position: relative;
  padding: 1.15rem 1.1rem 1.25rem;
  background: var(--ink-2);
  border-left: 2px solid var(--deep-teal);
}

.page-about .review-step__tag {
  display: inline-block;
  margin-bottom: 0.55rem;
  padding: 0.1rem 0.42rem;
  border: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.14em;
  color: var(--gold);
}

.page-about .review-step__title {
  margin: 0 0 0.5rem;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--paper);
}

.page-about .review-step p {
  margin: 0;
  max-width: 62ch;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: rgba(244, 239, 228, 0.78);
}

/* ---------- 覆盖网络 ---------- */
.page-about .reach-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
}

.page-about .reach {
  padding: 1.15rem 1.1rem 1.3rem;
  background: linear-gradient(160deg, rgba(33, 51, 59, 0.55), var(--ink-2) 62%);
}

.page-about .reach__num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: clamp(1.7rem, 4vw, 2.15rem);
  line-height: 1;
  color: var(--gold-bright);
}

.page-about .reach__label {
  display: block;
  margin-top: 0.4rem;
  font-size: 0.875rem;
  line-height: 1.5;
  color: var(--paper);
}

.page-about .reach p {
  margin: 0.65rem 0 0;
  font-size: 0.8125rem;
  line-height: 1.7;
  color: var(--archive);
}

/* ---------- 时间轴 ---------- */
.page-about .timeline {
  position: relative;
  margin: 1.5rem 0 0;
  padding: 0 0 0 1.75rem;
  list-style: none;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 0.9rem;
  bottom: 0.9rem;
  width: 1px;
  background: var(--line-strong);
}

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

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: calc(-1.75rem + 1px);
  top: 1.28rem;
  width: 9px;
  height: 9px;
  border: 1px solid var(--gold);
  background: var(--slate);
}

.page-about .timeline__node {
  border-bottom: 1px solid var(--line-soft);
}

.page-about .timeline__summary {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 0.7rem;
  padding: 0.8rem 0.25rem 0.8rem 0;
  cursor: pointer;
  list-style: none;
  transition: background-color var(--dur) var(--ease);
}

.page-about .timeline__summary::-webkit-details-marker {
  display: none;
}

.page-about .timeline__summary:hover {
  background: rgba(94, 122, 138, 0.1);
}

.page-about .timeline__summary:focus-visible {
  outline: 2px solid var(--gold-bright);
  outline-offset: 2px;
}

.page-about .timeline__year {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 0.9375rem;
  letter-spacing: 0.04em;
  color: var(--gold);
}

.page-about .timeline__label {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 1rem;
  line-height: 1.5;
  color: var(--paper);
}

.page-about .timeline__body {
  padding: 0.15rem 0.25rem 1rem 0;
}

.page-about .timeline__body p {
  margin: 0;
  max-width: 64ch;
  font-size: 0.9375rem;
  line-height: 1.82;
  color: rgba(244, 239, 228, 0.78);
}

/* ---------- 收束入口 ---------- */
.page-about .about-cta {
  margin-top: clamp(2.25rem, 5vw, 3.5rem);
  padding: clamp(1.5rem, 4vw, 2.5rem);
  border: 1px solid var(--line);
  border-top: 3px solid var(--gold);
  background: linear-gradient(150deg, rgba(33, 51, 59, 0.9), var(--ink-2) 70%);
}

.page-about .about-cta__title {
  margin: 0 0 0.75rem;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(1.2rem, 3vw, 1.5rem);
  line-height: 1.35;
  color: var(--paper);
}

.page-about .about-cta__text {
  margin: 0;
  max-width: 58ch;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: rgba(244, 239, 228, 0.76);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
  margin-top: 1.35rem;
}

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .review-steps {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .reach-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 860px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    gap: 2.25rem;
    align-items: start;
  }

  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 980px) {
  .page-about .about-body__inner {
    grid-template-columns: 168px minmax(0, 1fr);
    gap: clamp(2rem, 4vw, 3.75rem);
    align-items: start;
  }

  .page-about .about-index {
    display: block;
    position: sticky;
    top: 2rem;
  }

  .page-about .role__summary {
    padding: 1.1rem 1.35rem;
  }

  .page-about .role__body {
    padding: 0 1.35rem 1.35rem;
  }

  .page-about .reach-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__link,
  .page-about .role__summary,
  .page-about .role__mark::before,
  .page-about .role__mark::after,
  .page-about .timeline__summary {
    transition: none;
  }
}
<<<END>>>