.page-about {
  --about-line: #CBDAD0;
  --about-rail-w: 232px;
  background: var(--paper-050);
  color: var(--ink-950);
}

.page-about .breadcrumbs {
  padding-block: 18px 6px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-block: clamp(20px, 4vw, 44px) clamp(36px, 6vw, 72px);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(24px, 4vw, 48px);
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2.1rem, 5.2vw, 3.8rem);
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--ink-950);
  text-wrap: balance;
}

.page-about .about-hero__intro {
  margin: 20px 0 0;
  max-width: 32em;
  font-size: 1.0625rem;
  line-height: 1.8;
  color: var(--ink-900);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .about-hero__media {
  margin: 0;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 22px), calc(100% - 22px) 100%, 0 100%);
}

.page-about .about-hero__media .media-frame__img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .about-facts {
  list-style: none;
  margin: clamp(30px, 5vw, 52px) 0 0;
  padding: clamp(16px, 2.5vw, 22px) 0 0;
  display: grid;
  gap: 18px;
  border-top: 2px solid var(--ink-950);
}

.page-about .about-facts__item {
  display: grid;
  gap: 6px;
  align-content: start;
}

.page-about .about-facts__num {
  font-family: var(--font-mono);
  font-size: clamp(1.9rem, 3.4vw, 2.7rem);
  line-height: 1;
  color: var(--ink-950);
  letter-spacing: -0.01em;
}

.page-about .about-facts__label {
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--ink-700);
}

/* ---------- 双栏档案区 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 5vw, 60px);
  padding-block: clamp(28px, 5vw, 56px) clamp(48px, 8vw, 96px);
}

.page-about .about-rail {
  display: none;
}

.page-about .about-rail__label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-700);
}

.page-about .about-rail__list {
  list-style: none;
  margin: 16px 0 0;
  padding: 0;
  border-left: 1px solid var(--about-line);
}

.page-about .about-rail__link {
  display: flex;
  gap: 10px;
  align-items: baseline;
  padding: 9px 0 9px 16px;
  margin-left: -1px;
  border-left: 2px solid transparent;
  font-size: 0.9375rem;
  line-height: 1.5;
  color: var(--ink-700);
  text-decoration: none;
  transition: color 180ms var(--ease), border-color 180ms var(--ease);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--ink-950);
  border-left-color: var(--ink-950);
}

.page-about .about-rail__num {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  color: #7E958B;
}

.page-about .about-rail__meta {
  margin: 26px 0 0;
  padding: 14px 16px;
  background: var(--paper-200);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 14px), calc(100% - 14px) 100%, 0 100%);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  line-height: 1.9;
  color: var(--ink-700);
}

/* ---------- 章节通用 ---------- */
.page-about .about-chapter {
  padding-top: clamp(24px, 3vw, 34px);
  margin-bottom: clamp(48px, 7vw, 88px);
  border-top: 1px solid var(--about-line);
}

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

.page-about .about-body > .about-chapter:last-child {
  margin-bottom: 0;
}

.page-about .about-chapter__label {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  color: var(--ink-950);
}

.page-about .about-chapter__label .exhibit-label__num {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--ink-700);
}

.page-about .about-chapter__label .exhibit-label__rule {
  display: block;
  width: 24px;
  height: 3px;
  background: var(--ink-950);
}

.page-about .about-chapter__title {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.5rem, 2.6vw, 2.05rem);
  line-height: 1.25;
  letter-spacing: -0.01em;
  color: var(--ink-950);
  text-wrap: balance;
}

.page-about .about-chapter__lead {
  margin: 18px 0 0;
  max-width: 34em;
  font-size: 1rem;
  line-height: 1.8;
  color: var(--ink-900);
}

.page-about .about-note {
  margin: 20px 0 0;
  max-width: 38em;
  padding-left: 14px;
  border-left: 3px solid var(--ink-950);
  font-size: 0.9375rem;
  line-height: 1.75;
  color: var(--ink-700);
}

/* ---------- 人员清单 ---------- */
.page-about .about-ledger {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
}

.page-about .about-ledger__row {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 4px 16px;
  align-items: baseline;
  padding: 14px 0;
  border-bottom: 1px solid var(--about-line);
}

.page-about .about-ledger__row:first-child {
  border-top: 1px solid var(--ink-950);
}

.page-about .about-ledger__num {
  font-family: var(--font-mono);
  font-size: clamp(1.4rem, 2.4vw, 1.85rem);
  line-height: 1;
  color: var(--ink-950);
  min-width: 2.6ch;
}

.page-about .about-ledger__name {
  font-size: 1rem;
  font-weight: 700;
  color: var(--ink-950);
}

.page-about .about-ledger__desc {
  grid-column: 1 / -1;
  font-size: 0.9375rem;
  line-height: 1.75;
  color: var(--ink-700);
}

/* ---------- 流程 ---------- */
.page-about .about-flow {
  display: grid;
  gap: clamp(24px, 4vw, 40px);
  margin-top: 26px;
}

.page-about .about-flow__media {
  margin: 0;
  clip-path: polygon(0 0, 100% 0, 100% 100%, 18px 100%, 0 calc(100% - 18px));
}

.page-about .about-flow__media .media-frame__img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 5;
  object-fit: cover;
}

.page-about .about-flow__body .about-chapter__lead {
  margin-top: 0;
}

.page-about .about-steps {
  margin: 22px 0 0;
}

.page-about .about-step {
  position: relative;
  margin-bottom: 14px;
  background: var(--paper-200);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 16px 100%, 0 calc(100% - 16px));
}

.page-about .about-step + .about-step::before {
  content: "";
  position: absolute;
  top: -9px;
  left: 26px;
  width: 14px;
  height: 1px;
  background: var(--ink-700);
  transform: rotate(45deg);
  transform-origin: left center;
}

.page-about .about-step .fold__toggle {
  display: flex;
  width: 100%;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 16px 18px;
  background: transparent;
  border: 0;
  cursor: pointer;
  font: inherit;
  color: var(--ink-950);
  text-align: left;
}

.page-about .about-step .fold__title {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: 1rem;
  font-weight: 700;
}

.page-about .about-step__num {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--ink-700);
}

.page-about .about-step .fold__icon {
  flex: none;
  width: 9px;
  height: 9px;
  border-right: 2px solid var(--ink-950);
  border-bottom: 2px solid var(--ink-950);
  transform: rotate(45deg);
  transition: transform 220ms var(--ease);
}

.page-about .about-step .fold__toggle[aria-expanded="true"] .fold__icon {
  transform: rotate(-135deg);
}

.page-about .about-step .fold__panel {
  padding: 0 18px 18px;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--ink-900);
}

/* ---------- 时间轴 ---------- */
.page-about .about-stage-media {
  margin: clamp(22px, 3vw, 32px) 0 0;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 22px), calc(100% - 22px) 100%, 0 100%);
}

.page-about .about-stage-media .media-frame__img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 2 / 1;
  object-fit: cover;
}

.page-about .about-timeline {
  list-style: none;
  position: relative;
  margin: clamp(26px, 4vw, 40px) 0 0;
  padding: 0 0 0 26px;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--about-line);
}

.page-about .about-timeline__item {
  position: relative;
  padding-bottom: clamp(26px, 4vw, 38px);
}

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

.page-about .about-timeline__dot {
  position: absolute;
  left: -26px;
  top: 6px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--ink-950);
  box-shadow: 0 0 0 4px var(--lime-400);
}

.page-about .about-timeline__tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--ink-700);
}

.page-about .about-timeline__title {
  margin: 8px 0 0;
  font-size: 1.0625rem;
  font-weight: 700;
  line-height: 1.45;
  color: var(--ink-950);
}

.page-about .about-timeline__text {
  margin: 8px 0 0;
  max-width: 40em;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--ink-900);
}

/* ---------- 数据来源（深色面板） ---------- */
.page-about .about-source {
  background: var(--ink-950);
  color: var(--paper-050);
  padding: clamp(24px, 4.5vw, 50px);
}

.page-about .about-source .about-chapter__label {
  color: var(--slate-400);
}

.page-about .about-source .about-chapter__label .exhibit-label__num {
  color: var(--slate-400);
}

.page-about .about-source .about-chapter__label .exhibit-label__rule {
  background: var(--lime-400);
}

.page-about .about-source__title {
  color: var(--paper-050);
}

.page-about .about-source__grid {
  display: grid;
  gap: clamp(24px, 4vw, 40px);
  margin-top: 20px;
}

.page-about .about-source__lead {
  margin: 0;
  max-width: 34em;
  font-size: 0.9375rem;
  line-height: 1.85;
  color: #D6E2DA;
}

.page-about .about-source__list {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
}

.page-about .about-source__list li {
  display: grid;
  grid-template-columns: 3.6rem minmax(0, 1fr);
  gap: 4px 16px;
  padding: 13px 0;
  border-bottom: 1px solid var(--ink-700);
  font-size: 0.9375rem;
  line-height: 1.8;
  color: #D6E2DA;
}

.page-about .about-source__list li:first-child {
  border-top: 1px solid var(--ink-700);
}

.page-about .about-source__tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--lime-400);
  padding-top: 2px;
}

.page-about .about-source__stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(96px, 1fr));
  gap: 18px;
  align-content: start;
  padding-top: 22px;
  border-top: 1px solid var(--ink-700);
}

.page-about .about-source__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 3vw, 2.1rem);
  line-height: 1;
  color: var(--lime-400);
}

.page-about .about-source__cap {
  display: block;
  margin-top: 8px;
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--slate-400);
}

/* ---------- 说明牌 ---------- */
.page-about .about-plates {
  list-style: none;
  margin: clamp(24px, 4vw, 36px) 0 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .about-plate {
  background: var(--paper-200);
  padding: 18px 20px 20px;
  clip-path: polygon(0 0, calc(100% - 16px) 0, 100% 16px, 100% 100%, 0 100%);
}

.page-about .about-plate__num {
  display: inline-block;
  padding: 2px 7px;
  background: var(--ink-950);
  color: var(--lime-400);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
}

.page-about .about-plate h3 {
  margin: 12px 0 0;
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.5;
  color: var(--ink-950);
}

.page-about .about-plate p {
  margin: 8px 0 0;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--ink-900);
}

/* ---------- 天津 ---------- */
.page-about .about-hq {
  padding-block: clamp(48px, 8vw, 92px);
}

.page-about .about-hq__grid {
  display: grid;
  gap: clamp(28px, 5vw, 56px);
}

.page-about .about-hq__title {
  margin-top: 12px;
  color: var(--paper-050);
}

.page-about .about-hq__text {
  margin: 18px 0 0;
  max-width: 34em;
  font-size: 1rem;
  line-height: 1.85;
  color: #D6E2DA;
}

.page-about .about-hq__more {
  margin: 22px 0 0;
}

.page-about .about-hq__link {
  color: var(--lime-400);
  text-decoration: none;
  border-bottom: 1px solid var(--lime-400);
  padding-bottom: 2px;
  font-size: 0.9375rem;
}

.page-about .about-hq__link:hover {
  color: var(--lime-100);
  border-bottom-color: var(--lime-100);
}

.page-about .about-hq__list {
  list-style: none;
  margin: 0;
  padding: 0;
  align-self: start;
}

.page-about .about-hq__list li {
  padding: 16px 0;
  border-top: 1px solid var(--ink-700);
}

.page-about .about-hq__list li:last-child {
  border-bottom: 1px solid var(--ink-700);
}

.page-about .about-hq__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.4rem, 2.8vw, 1.9rem);
  line-height: 1.1;
  color: var(--lime-400);
}

.page-about .about-hq__cap {
  display: block;
  margin-top: 6px;
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--slate-400);
}

/* ---------- 结尾 ---------- */
.page-about .about-cta {
  padding-block: clamp(44px, 7vw, 84px);
  color: var(--paper-050);
}

.page-about .about-cta__inner {
  max-width: 46rem;
}

.page-about .about-cta__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.6rem, 3.2vw, 2.4rem);
  line-height: 1.2;
  color: var(--paper-050);
}

.page-about .about-cta__text {
  margin: 16px 0 0;
  max-width: 36em;
  font-size: 1rem;
  line-height: 1.8;
  color: #E4EFE7;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-facts {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
  }

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

@media (min-width: 720px) {
  .page-about .about-ledger__row {
    grid-template-columns: 4.5rem 10rem minmax(0, 1fr);
    gap: 4px 20px;
  }

  .page-about .about-ledger__desc {
    grid-column: 3;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    align-items: end;
  }

  .page-about .about-flow {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
    align-items: start;
  }

  .page-about .about-source__grid {
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 0.8fr);
  }

  .page-about .about-source__stats {
    grid-template-columns: minmax(0, 1fr);
    gap: 22px;
    padding-top: 0;
    border-top: 0;
    padding-left: 24px;
    border-left: 1px solid var(--ink-700);
  }

  .page-about .about-hq__grid {
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 0.8fr);
    align-items: start;
  }
}

@media (min-width: 960px) {
  .page-about .about-shell {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: calc(var(--header-h-compact) + 28px);
  }
}
<<<END>>>