.page-about {
  padding-bottom: clamp(56px, 9vw, 120px);
}

/* ---------- 首屏声明 ---------- */
.page-about .about-lede {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
  align-items: end;
  padding: clamp(14px, 3vw, 26px) 0 clamp(38px, 6vw, 68px);
}

.page-about .about-lede__kicker {
  margin: 0 0 16px;
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--muted);
}

.page-about .about-lede__title {
  margin: 0 0 20px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(29px, 6.4vw, 52px);
  line-height: 1.1;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .about-hl {
  background: linear-gradient(transparent 60%, rgba(242, 98, 27, .55) 60%);
  padding: 0 2px;
}

.page-about .about-lede__lead {
  margin: 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.8;
  color: rgba(242, 231, 212, .84);
}

.page-about .about-lede__facts {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 24px;
  margin: 26px 0 14px;
  padding: 0;
  font-size: 13px;
  color: var(--muted);
}

.page-about .about-lede__facts li {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding-left: 11px;
  border-left: 2px solid var(--wood);
}

.page-about .about-lede__facts .stat-num {
  font-size: 21px;
  line-height: 1;
}

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

.page-about .about-lede__figure .media-frame__inner img,
.page-about .about-flow-figure .media-frame__inner img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: 16px 4px 16px 4px;
  border: 1px solid var(--line);
}

.page-about .media-frame__caption {
  margin-top: 10px;
  font-size: 12px;
  line-height: 1.7;
  color: var(--muted);
}

@media (min-width: 900px) {
  .page-about .about-lede {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, .88fr);
    gap: 56px;
  }
}

/* ---------- 双栏骨架 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
  align-items: start;
}

@media (min-width: 960px) {
  .page-about .about-body {
    grid-template-columns: var(--rail) minmax(0, 1fr);
    gap: 56px;
  }
}

/* ---------- 左栏章节刻度 ---------- */
.page-about .about-rail__title {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: .2em;
  color: var(--muted);
}

.page-about .about-rail__list {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 2px 10px;
  margin: 0;
  padding: 0 0 6px;
  border-bottom: 1px solid var(--line);
}

.page-about .about-rail__link {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 7px 6px;
  color: var(--muted);
  text-decoration: none;
  font-size: 13px;
  line-height: 1.4;
  border-left: 2px solid transparent;
  transition: color var(--step), border-color var(--step), background var(--step);
}

.page-about .about-rail__num {
  font-family: var(--font-display);
  font-size: 11px;
  letter-spacing: .04em;
  font-variant-numeric: tabular-nums;
  color: var(--ink-500);
}

.page-about .about-rail__link:hover {
  color: var(--paper);
}

.page-about .about-rail__link.is-active,
.page-about .about-rail__link[aria-current="true"] {
  color: var(--paper);
  border-left-color: var(--orange);
  background: linear-gradient(90deg, rgba(242, 98, 27, .16), transparent 74%);
}

.page-about .about-rail__link.is-active .about-rail__num,
.page-about .about-rail__link[aria-current="true"] .about-rail__num {
  color: var(--orange-lt);
}

@media (min-width: 960px) {
  .page-about .about-rail {
    position: sticky;
    top: 104px;
    align-self: start;
  }

  .page-about .about-rail__list {
    grid-template-columns: minmax(0, 1fr);
    gap: 0;
    padding-left: 18px;
    border-bottom: 0;
    position: relative;
  }

  .page-about .about-rail__list::before {
    content: "";
    position: absolute;
    left: 5px;
    top: 12px;
    bottom: 12px;
    border-left: 2px dashed var(--line);
  }

  .page-about .about-rail__link {
    display: block;
    padding: 10px 10px 10px 12px;
    border-left: 2px solid var(--line);
  }

  .page-about .about-rail__num {
    display: block;
    margin-bottom: 3px;
  }
}

/* ---------- 章节 ---------- */
.page-about .about-chapter {
  border-top: 8px solid var(--wood);
  padding-top: clamp(22px, 3.4vw, 34px);
  margin-top: clamp(44px, 6.5vw, 84px);
}

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

.page-about .about-chapter--airy {
  margin-top: clamp(68px, 11vw, 140px);
  padding-top: clamp(30px, 4.4vw, 48px);
}

.page-about .about-chapter__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 14px;
  align-items: baseline;
  margin-bottom: 20px;
}

.page-about .about-chapter__num {
  font-family: var(--font-display);
  font-size: clamp(27px, 4.6vw, 40px);
  line-height: 1;
  font-variant-numeric: tabular-nums;
  color: var(--orange);
}

.page-about .about-chapter__title {
  margin: 0;
  font-size: clamp(20px, 3.3vw, 29px);
  font-weight: 700;
  line-height: 1.28;
  color: var(--paper);
}

.page-about .about-p {
  margin: 0 0 15px;
  max-width: 68ch;
  font-size: 16px;
  line-height: 1.8;
  color: rgba(242, 231, 212, .84);
}

.page-about .about-chapter--airy .about-p {
  line-height: 1.9;
}

.page-about .about-inline-link {
  color: var(--orange-lt);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 164, 92, .5);
}

.page-about .about-inline-link:hover {
  border-bottom-color: var(--orange-lt);
}

/* ---------- 时间轴 ---------- */
.page-about .about-tl {
  list-style: none;
  margin: 26px 0 0;
  padding: 0 0 0 24px;
  position: relative;
}

.page-about .about-tl::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 8px;
  bottom: 20px;
  border-left: 2px dashed var(--line-strong);
}

.page-about .about-tl__item {
  position: relative;
  padding: 0 0 26px;
}

.page-about .about-tl__item::before {
  content: "";
  position: absolute;
  left: -20px;
  top: 5px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--ink-900);
  border: 2px solid var(--orange);
}

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

.page-about .about-tl__era {
  margin: 0 0 4px;
  font-family: var(--font-display);
  font-size: 13px;
  letter-spacing: .06em;
  font-variant-numeric: tabular-nums;
  color: var(--orange-lt);
}

.page-about .about-tl__title {
  margin: 0 0 7px;
  font-size: 17px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .about-tl__text {
  margin: 0;
  max-width: 66ch;
  font-size: 14px;
  line-height: 1.78;
  color: rgba(242, 231, 212, .74);
}

/* ---------- 校订流程 ---------- */
.page-about .about-steps {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
}

.page-about .about-steps__item {
  position: relative;
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 14px;
  padding-bottom: 24px;
}

.page-about .about-steps__item:not(:last-child)::before {
  content: "";
  position: absolute;
  left: 16px;
  top: 36px;
  bottom: 2px;
  border-left: 2px dashed var(--line);
}

.page-about .about-steps__num {
  z-index: 1;
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  border: 2px solid var(--orange);
  background: var(--ink-700);
  color: var(--paper);
  font-family: var(--font-display);
  font-size: 13px;
  font-variant-numeric: tabular-nums;
}

.page-about .about-steps__title {
  margin: 3px 0 6px;
  font-size: 16px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .about-steps__text {
  margin: 0 0 8px;
  max-width: 68ch;
  font-size: 14px;
  line-height: 1.75;
  color: rgba(242, 231, 212, .76);
}

.page-about .about-steps__meta {
  margin: 0;
  padding-left: 11px;
  border-left: 2px solid var(--line);
  font-size: 12px;
  line-height: 1.7;
  color: var(--muted);
  transition: color var(--step), border-color var(--step);
}

.page-about .about-steps__item:hover .about-steps__meta,
.page-about .about-steps__item:focus-within .about-steps__meta {
  color: var(--orange-lt);
  border-left-color: var(--orange);
}

.page-about .about-flow-figure {
  margin: 30px 0 26px;
}

/* ---------- 团队表 ---------- */
.page-about .about-crew {
  list-style: none;
  margin: 26px 0 24px;
  padding: 0;
  border-top: 1px solid var(--line-strong);
}

.page-about .about-crew__row {
  display: grid;
  grid-template-columns: 60px minmax(0, 1fr);
  gap: 4px 14px;
  padding: 16px 2px;
  border-bottom: 1px solid var(--line);
}

.page-about .about-crew__num {
  grid-row: 1;
  grid-column: 1;
  font-family: var(--font-display);
  font-size: 25px;
  line-height: 1;
  font-variant-numeric: tabular-nums;
  color: var(--orange);
}

.page-about .about-crew__name {
  grid-row: 1;
  grid-column: 2;
  font-size: 15px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-crew__note {
  grid-row: 2;
  grid-column: 2;
  font-size: 13px;
  line-height: 1.72;
  color: var(--muted);
}

@media (min-width: 720px) {
  .page-about .about-crew__row {
    grid-template-columns: 72px 160px minmax(0, 1fr);
    align-items: baseline;
  }

  .page-about .about-crew__name {
    grid-row: 1;
    grid-column: 2;
  }

  .page-about .about-crew__note {
    grid-row: 1;
    grid-column: 3;
  }
}

/* ---------- 口径说明书折叠卡 ---------- */
.page-about .about-spec {
  display: grid;
  gap: 10px;
  margin: 26px 0 28px;
}

.page-about .about-spec__item {
  background: var(--paper);
  color: var(--paper-ink);
  border: 1px solid rgba(30, 21, 18, .16);
  border-radius: 16px 4px 16px 4px;
  overflow: hidden;
  transition: box-shadow var(--step);
}

.page-about .about-spec__item[open] {
  box-shadow: inset 4px 0 0 var(--orange);
}

.page-about .about-spec__summary {
  position: relative;
  padding: 15px 48px 15px 18px;
  cursor: pointer;
  list-style: none;
  font-size: 15px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--paper-ink);
}

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

.page-about .about-spec__summary::after {
  content: "+";
  position: absolute;
  right: 16px;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-display);
  font-size: 18px;
  line-height: 1;
  color: var(--orange);
}

.page-about .about-spec__item[open] .about-spec__summary::after {
  content: "\2013";
}

.page-about .about-spec__body {
  padding: 2px 18px 16px;
  border-top: 1px dashed rgba(30, 21, 18, .22);
}

.page-about .about-spec__body p {
  margin: 12px 0 0;
  max-width: 64ch;
  font-size: 14px;
  line-height: 1.78;
  color: var(--paper-soft);
}

/* ---------- 城市横幅 ---------- */
.page-about .about-banner {
  position: relative;
  margin: 30px 0 26px;
  border-radius: 16px 4px 16px 4px;
  overflow: hidden;
  border: 1px solid var(--line);
}

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

.page-about .about-banner__cap {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 34px 18px 14px;
  background: linear-gradient(transparent, rgba(21, 10, 38, .94));
  font-size: 12px;
  line-height: 1.7;
  color: rgba(242, 231, 212, .8);
}

/* ---------- 动作区 ---------- */
.page-about .about-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 26px 0 14px;
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .about-steps__meta,
  .page-about .about-spec__item {
    transition: none;
  }
}
<<<END>>>