.page-about {
  --about-rail: 252px;
  --about-gap: clamp(30px, 4.6vw, 68px);
  --about-edge: clamp(20px, 6vw, 80px);
  color: var(--fog);
  counter-reset: chapter;
  min-width: 0;
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumbs {
  margin: 26px 0 16px;
}
.page-about .about-crumbs .crumbs {
  font-size: 13px;
  letter-spacing: .04em;
}

/* ---------- 框景首屏 ---------- */
.page-about .about-frame {
  position: relative;
  border-top: 1px solid var(--line-strong);
  border-bottom: 1px solid var(--line-strong);
  background:
    radial-gradient(120% 110% at 86% 0%, rgba(56, 224, 208, .13), transparent 58%),
    var(--ink-800);
  overflow: hidden;
}
.page-about .about-frame::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 26px;
  background-image: repeating-linear-gradient(90deg, var(--line-strong) 0 1px, transparent 1px 40px);
  opacity: .5;
  pointer-events: none;
}

.page-about .about-frame__bar {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 18px;
  justify-content: space-between;
  padding: 10px var(--about-edge);
  border-bottom: 1px solid var(--line);
  background: rgba(12, 20, 48, .62);
  font-size: 11.5px;
  letter-spacing: .14em;
  color: var(--muted);
}
.page-about .about-frame__stamp {
  color: var(--amber);
}

.page-about .about-frame__grid {
  display: grid;
  gap: 30px;
  padding: clamp(32px, 5vw, 62px) var(--about-edge) clamp(44px, 6vw, 78px);
}

.page-about .about-frame__title {
  margin: 14px 0 0;
  font-size: clamp(40px, 7.4vw, 76px);
  font-weight: 900;
  line-height: 1.04;
  letter-spacing: -.02em;
  color: var(--white);
}
.page-about .about-frame__sub {
  display: block;
  margin-top: 12px;
  font-size: clamp(17px, 2.3vw, 25px);
  font-weight: 600;
  letter-spacing: 0;
  color: var(--cyan);
}
.page-about .about-frame__lead {
  margin: 22px 0 0;
  max-width: 34em;
  font-size: clamp(16px, 1.6vw, 19px);
  line-height: 1.8;
  color: var(--fog);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 34px 0 0;
  border: 1px solid var(--line);
  background: var(--line);
}
.page-about .about-facts__item {
  background: var(--ink-800);
  padding: 14px 16px;
}
.page-about .about-facts dt {
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--muted);
}
.page-about .about-facts dd {
  margin: 8px 0 0;
  font-size: clamp(18px, 2.2vw, 21px);
  font-weight: 700;
  color: var(--white);
  letter-spacing: -.01em;
}

.page-about .about-frame__aside {
  margin-top: 32px;
  padding-top: 22px;
  border-top: 1px solid var(--line-strong);
  font-size: 15px;
  line-height: 1.85;
}
.page-about .about-frame__aside p {
  margin: 0 0 14px;
}
.page-about .about-frame__link {
  font-size: 14px;
}

.page-about .about-aside__title {
  margin: 0;
  padding-bottom: 9px;
  border-bottom: 1px solid var(--line);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--muted);
}

/* ---------- 主体：左索引 + 右章节 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  margin-top: clamp(36px, 5vw, 72px);
  margin-bottom: clamp(48px, 7vw, 96px);
}

.page-about .about-rail {
  border: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(24, 36, 76, .92), rgba(16, 26, 58, .5));
  padding: 18px 14px;
}
.page-about .about-rail__caption {
  margin: 0 0 14px;
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--muted);
}
.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
}
.page-about .about-rail__link {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 10px;
  align-items: baseline;
  padding: 9px 10px;
  border-left: 2px solid transparent;
  color: var(--fog);
  font-size: 14px;
  line-height: 1.5;
  text-decoration: none;
  transition: border-color .18s var(--ease), color .18s var(--ease), background-color .18s var(--ease);
}
.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  border-left-color: var(--amber);
  color: var(--white);
  background: rgba(56, 224, 208, .07);
}
.page-about .about-rail__num {
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--amber);
}

.page-about .about-flow {
  display: grid;
  gap: clamp(44px, 6vw, 82px);
  min-width: 0;
}

/* ---------- 章节通用 ---------- */
.page-about .about-chapter {
  counter-increment: chapter;
  scroll-margin-top: 132px;
  min-width: 0;
}
.page-about .about-chapter__head {
  display: grid;
  grid-template-columns: 24px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding-top: 22px;
  border-top: 1px solid var(--line-strong);
}
.page-about .about-chapter__mark {
  display: flex;
  align-items: flex-end;
  justify-content: center;
  min-height: 56px;
  height: 100%;
  border-left: 1px solid var(--amber);
}
.page-about .about-chapter__mark::before {
  content: counter(chapter, decimal-leading-zero);
  writing-mode: vertical-rl;
  transform: rotate(180deg);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .22em;
  color: var(--amber);
  opacity: .92;
}
.page-about .about-chapter:target .about-chapter__mark {
  border-left-color: var(--cyan);
}
.page-about .about-chapter:target .about-chapter__mark::before {
  color: var(--cyan);
}
.page-about .about-chapter__intro h2 {
  margin: 0;
  font-size: clamp(24px, 3.3vw, 34px);
  font-weight: 900;
  line-height: 1.25;
  letter-spacing: -.01em;
  color: var(--white);
}
.page-about .about-chapter__lead {
  margin: 14px 0 0;
  max-width: 36em;
  font-size: 17px;
  line-height: 1.78;
  color: var(--fog);
}

.page-about .about-chapter__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 20px;
  margin: 18px 0 0;
  font-size: 12px;
  letter-spacing: .05em;
  color: var(--muted);
}
.page-about .about-rev {
  position: relative;
  color: var(--amber);
}
.page-about .about-rev__more {
  position: absolute;
  left: 0;
  top: calc(100% + 8px);
  z-index: 6;
  display: block;
  width: min(330px, 78vw);
  padding: 12px 14px;
  border: 1px solid var(--line-strong);
  background: var(--ink-700);
  color: var(--fog);
  font-size: 12.5px;
  line-height: 1.75;
  letter-spacing: 0;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-4px);
  transition: opacity .18s var(--ease), transform .18s var(--ease), visibility .18s linear;
}
.page-about .about-rev:hover .about-rev__more {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.page-about .about-chapter__body {
  margin-top: 28px;
}

/* ---------- 双栏：主文 + 旁注 ---------- */
.page-about .about-cols {
  display: grid;
  gap: 26px;
}
.page-about .about-cols__main p {
  margin: 0 0 18px;
  max-width: 40em;
  font-size: 16px;
  line-height: 1.9;
  color: var(--fog);
}
.page-about .about-cols__main p:last-child {
  margin-bottom: 0;
}
.page-about .about-cols__aside {
  padding-top: 18px;
  border-top: 1px solid var(--line);
}

.page-about .about-plain {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
  display: grid;
  gap: 9px;
}
.page-about .about-plain li {
  position: relative;
  padding-left: 18px;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--fog);
}
.page-about .about-plain li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .72em;
  width: 8px;
  height: 1px;
  background: var(--orange);
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 0;
}
.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--line-strong);
  background: var(--ink-700);
  object-fit: cover;
}
.page-about .about-figure--wide img {
  aspect-ratio: 1400 / 600;
}
.page-about .about-figure figcaption {
  margin-top: 10px;
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--muted);
}
.page-about .about-figure--wide {
  margin-bottom: 30px;
}

/* ---------- 沿革时间轴 ---------- */
.page-about .about-track {
  list-style: none;
  margin: 0 0 0 5px;
  padding: 0 0 0 22px;
  border-left: 1px solid var(--line-strong);
  display: grid;
  gap: 28px;
}
.page-about .about-track__item {
  position: relative;
}
.page-about .about-track__item::before {
  content: "";
  position: absolute;
  left: -27px;
  top: 5px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--ink-900);
  border: 2px solid var(--amber);
}
.page-about .about-track__item:first-child::before {
  background: var(--amber);
}
.page-about .about-track__rev {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--amber);
}
.page-about .about-track__title {
  margin: 8px 0 0;
  font-size: 18px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--white);
}
.page-about .about-track__desc {
  margin: 8px 0 0;
  max-width: 38em;
  font-size: 15px;
  line-height: 1.85;
  color: var(--fog);
}

/* ---------- 机制：纸面 + 折叠 ---------- */
.page-about .about-rhythm {
  display: grid;
  gap: 26px;
}
.page-about .about-paper {
  padding: clamp(20px, 3vw, 34px);
  border: 1px solid rgba(28, 33, 54, .2);
  background: var(--paper);
  color: var(--paper-ink);
}
.page-about .about-paper h3 {
  margin: 0 0 12px;
  font-size: 17px;
  font-weight: 900;
  color: var(--paper-ink);
}
.page-about .about-paper h3 + p {
  margin-top: 0;
}
.page-about .about-paper p {
  margin: 0 0 14px;
  font-size: 15.5px;
  line-height: 1.88;
  color: var(--paper-ink);
}
.page-about .about-paper p:last-child {
  margin-bottom: 0;
}

.page-about .about-fold {
  margin-top: 12px;
  border: 1px solid var(--line);
  background: rgba(24, 36, 76, .55);
}
.page-about .about-fold summary {
  display: flex;
  gap: 12px;
  align-items: baseline;
  padding: 14px 18px;
  list-style: none;
  cursor: pointer;
  font-size: 15px;
  font-weight: 600;
  line-height: 1.6;
  color: var(--white);
  transition: background-color .18s var(--ease);
}
.page-about .about-fold summary::-webkit-details-marker {
  display: none;
}
.page-about .about-fold summary::before {
  content: "＋";
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--cyan);
}
.page-about .about-fold[open] summary::before {
  content: "－";
}
.page-about .about-fold summary:hover,
.page-about .about-fold summary:focus-visible {
  background: rgba(56, 224, 208, .08);
}
.page-about .about-fold__body {
  padding: 2px 18px 18px 46px;
  font-size: 15px;
  line-height: 1.88;
  color: var(--fog);
}
.page-about .about-fold__body p {
  margin: 0;
  max-width: 38em;
}

/* ---------- 团队分工 ---------- */
.page-about .about-team {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}
.page-about .about-team__item {
  padding: 20px clamp(16px, 2.6vw, 26px);
  border: 1px solid var(--line);
  border-left: 2px solid var(--amber);
  background: linear-gradient(120deg, rgba(24, 36, 76, .92), rgba(16, 26, 58, .6));
  transition: border-color .18s var(--ease), transform .18s var(--ease);
}
.page-about .about-team__item:hover {
  border-color: var(--cyan);
  transform: translateY(-2px);
}
.page-about .about-team__role {
  margin: 0;
  font-size: 11.5px;
  letter-spacing: .12em;
  color: var(--cyan);
}
.page-about .about-team__num {
  margin: 14px 0 0;
  font-size: 32px;
  font-weight: 900;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--white);
}
.page-about .about-team__num span {
  margin-left: 6px;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0;
  color: var(--muted);
}
.page-about .about-team__desc {
  margin: 12px 0 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--fog);
}

/* ---------- 区域 ---------- */
.page-about .about-region {
  display: grid;
  gap: 26px;
}
.page-about .about-region__copy p {
  margin: 0 0 18px;
  max-width: 38em;
  font-size: 16px;
  line-height: 1.9;
  color: var(--fog);
}
.page-about .about-region__stats {
  display: grid;
  gap: 1px;
  margin: 24px 0 0;
  border: 1px solid var(--line);
  background: var(--line);
}
.page-about .about-region__stat {
  padding: 14px 16px;
  background: var(--ink-800);
}
.page-about .about-region__stat dt {
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--muted);
}
.page-about .about-region__stat dd {
  margin: 8px 0 0;
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--white);
}

/* ---------- 合规台账 ---------- */
.page-about .about-ledger {
  border: 1px solid var(--line-strong);
  background: linear-gradient(180deg, rgba(24, 36, 76, .9), rgba(16, 26, 58, .6));
  padding: clamp(20px, 3vw, 30px);
}
.page-about .about-ledger__list {
  margin: 0;
  display: grid;
  gap: 0;
}
.page-about .about-ledger__row {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 4px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}
.page-about .about-ledger__row:first-child {
  padding-top: 0;
}
.page-about .about-ledger__row dt {
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--amber);
}
.page-about .about-ledger__row dd {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.7;
  color: var(--white);
  word-break: break-word;
}
.page-about .about-ledger__note {
  margin: 22px 0 0;
  max-width: 42em;
  font-size: 14.5px;
  line-height: 1.88;
  color: var(--fog);
}

/* ---------- 收尾入口 ---------- */
.page-about .about-next {
  padding-top: 26px;
  border-top: 1px solid var(--line-strong);
}
.page-about .about-next__title {
  margin: 0 0 20px;
  font-size: 18px;
  font-weight: 900;
  letter-spacing: .02em;
  color: var(--white);
}
.page-about .about-next__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}
.page-about .about-next__link {
  display: grid;
  gap: 6px;
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-left: 2px solid var(--amber);
  text-decoration: none;
  transition: border-color .18s var(--ease), background-color .18s var(--ease), transform .18s var(--ease);
}
.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  border-left-color: var(--cyan);
  background: rgba(56, 224, 208, .07);
  transform: translateY(-2px);
}
.page-about .about-next__label {
  font-size: 16px;
  font-weight: 700;
  color: var(--white);
}
.page-about .about-next__desc {
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 中等屏 ---------- */
@media (min-width: 720px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .about-cols {
    grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
    gap: clamp(24px, 3vw, 44px);
    align-items: start;
  }
  .page-about .about-cols__aside {
    padding-top: 0;
    padding-left: 20px;
    border-top: 0;
    border-left: 1px solid var(--line);
  }
  .page-about .about-region__stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .about-ledger__row {
    grid-template-columns: 150px minmax(0, 1fr);
    gap: 16px;
    align-items: baseline;
  }
  .page-about .about-next__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-team {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: 20px;
  }
  .page-about .about-team__item:nth-child(even) {
    margin-top: 28px;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 960px) {
  .page-about .about-frame__grid {
    grid-template-columns: minmax(0, 1.65fr) minmax(0, .95fr);
    gap: clamp(32px, 4vw, 72px);
  }
  .page-about .about-frame__aside {
    margin-top: 0;
    padding-top: 6px;
    padding-left: clamp(24px, 3vw, 42px);
    border-top: 0;
    border-left: 1px solid var(--line-strong);
  }
  .page-about .about-rhythm {
    grid-template-columns: minmax(0, 1.45fr) minmax(0, 1fr);
    gap: clamp(24px, 3vw, 44px);
    align-items: start;
  }
  .page-about .about-region {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr);
    gap: clamp(24px, 3vw, 46px);
    align-items: start;
  }
}

@media (min-width: 1024px) {
  .page-about .about-body {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    align-items: start;
  }
  .page-about .about-rail {
    position: sticky;
    top: 124px;
    padding: 22px 18px;
  }
}

/* ---------- 窄屏微调 ---------- */
@media (max-width: 767px) {
  .page-about .about-chapter__meta {
    margin-left: 0;
  }
  .page-about .about-rev__more {
    position: static;
    width: auto;
    margin-top: 8px;
    opacity: 1;
    visibility: visible;
    transform: none;
  }
  .page-about .about-chapter__mark {
    min-height: 44px;
  }
  .page-about .about-frame__bar {
    letter-spacing: .1em;
  }
  .page-about .about-frame__stamp {
    color: var(--muted);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .about-team__item,
  .page-about .about-next__link,
  .page-about .about-rev__more {
    transition: none;
  }
  .page-about .about-team__item:hover,
  .page-about .about-next__link:hover {
    transform: none;
  }
}
<<<END>>>