.page-about {
  --about-hair: rgba(106, 83, 39, .46);
  --about-hair-soft: rgba(106, 83, 39, .26);
  --about-gold-soft: rgba(212, 163, 74, .16);
  --about-silver-90: rgba(232, 230, 225, .9);
  position: relative;
  display: block;
  overflow-x: hidden;
  padding-bottom: clamp(48px, 8vw, 96px);
  color: var(--about-silver-90);
  font-family: var(--font-body);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  border-bottom: 1px solid var(--about-hair-soft);
  background:
    radial-gradient(120% 80% at 82% 0%, rgba(212, 163, 74, .1), transparent 62%),
    radial-gradient(90% 70% at 6% 100%, rgba(200, 56, 46, .08), transparent 60%),
    var(--ink);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 8px;
  pointer-events: none;
  opacity: .45;
  background-image:
    radial-gradient(circle at 50% 100%, rgba(212, 163, 74, .42) 0 55%, transparent 56%),
    radial-gradient(circle at 50% 100%, rgba(212, 163, 74, .24) 0 55%, transparent 56%);
  background-size: 16px 8px, 16px 8px;
  background-position: 0 0, 8px 0;
}

.page-about .about-hero__inner {
  position: relative;
  padding: clamp(22px, 5vw, 42px) 0 clamp(26px, 5vw, 46px);
}

.page-about .about-hero__kicker {
  margin: 18px 0 0;
}

.page-about .about-hero__title {
  margin: 16px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(30px, 8vw, 62px);
  line-height: 1.16;
  letter-spacing: .01em;
  color: var(--gold-hi);
  text-shadow: 0 0 26px rgba(212, 163, 74, .18);
}

.page-about .about-hero__lede {
  margin: 18px 0 0;
  max-width: 60ch;
  font-size: 16px;
  line-height: 1.85;
  letter-spacing: .04em;
  color: var(--about-silver-90);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-hero__fact {
  display: flex;
  align-items: baseline;
  gap: 8px;
  min-height: 48px;
  padding: 11px 12px;
  border: 1px solid var(--about-hair-soft);
  background: var(--ink-2);
}

.page-about .about-hero__fact-num {
  font-family: var(--font-num);
  font-size: 20px;
  letter-spacing: -.02em;
  color: var(--gold);
}

.page-about .about-hero__fact-txt {
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--silver-2);
}

.page-about .about-hero__figure {
  position: relative;
  margin: 0;
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  opacity: .84;
}

.page-about .about-hero__figure::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(180deg, rgba(11, 11, 15, .58), rgba(11, 11, 15, .12) 42%, rgba(11, 11, 15, .92));
}

/* ---------- 主体分屏 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(22px, 5vw, 40px);
  padding-top: clamp(26px, 5vw, 56px);
}

/* 左侧刻度导航 */
.page-about .about-rail {
  min-width: 0;
}

.page-about .about-rail__label {
  margin: 0 0 10px;
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--silver-2);
}

.page-about .about-rail__list {
  display: flex;
  gap: 10px;
  margin: 0;
  padding: 0 0 8px;
  list-style: none;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .about-rail__item {
  flex: 0 0 auto;
}

.page-about .about-rail__link {
  display: flex;
  align-items: center;
  gap: 8px;
  min-height: 48px;
  padding: 8px 12px;
  border: 1px solid transparent;
  color: var(--silver-2);
  text-decoration: none;
  font-size: 13px;
  letter-spacing: .08em;
  white-space: nowrap;
  transition: color 240ms var(--ease), border-color 240ms var(--ease), background-color 240ms var(--ease);
}

.page-about .about-rail__link::before {
  content: "";
  flex: none;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--about-hair);
  transition: background-color 240ms var(--ease), box-shadow 240ms var(--ease);
}

.page-about .about-rail__num {
  font-family: var(--font-num);
  font-size: 12px;
  color: inherit;
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--gold-hi);
  border-color: var(--about-hair);
}

.page-about .about-rail__link[data-active] {
  color: var(--gold-hi);
  border-color: var(--line);
  background: var(--ink-2);
}

.page-about .about-rail__link[data-active]::before {
  background: var(--cinnabar);
  box-shadow: 0 0 0 3px rgba(200, 56, 46, .22);
}

/* 右侧卷轴 */
.page-about .about-scroll {
  min-width: 0;
}

.page-about .about-chapter {
  position: relative;
  padding: clamp(26px, 5vw, 52px) 0;
  border-top: 1px solid var(--about-hair-soft);
}

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

.page-about .chapter__index {
  display: block;
  font-family: var(--font-num);
  font-size: clamp(32px, 8vw, 58px);
  line-height: 1;
  letter-spacing: .02em;
  color: var(--about-gold-soft);
}

.page-about .chapter__title {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(21px, 5vw, 30px);
  line-height: 1.35;
  letter-spacing: .02em;
  color: var(--silver);
}

.page-about .chapter__body {
  margin-top: 16px;
}

.page-about .chapter__body p {
  margin: 0 0 1.15em;
  max-width: 64ch;
  font-size: 16px;
  line-height: 1.85;
  letter-spacing: .04em;
  color: var(--about-silver-90);
}

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

.page-about .chapter__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(20px, 4vw, 36px);
  margin-top: 16px;
}

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

.page-about .chapter__main > p {
  margin: 20px 0 0;
  max-width: 64ch;
  font-size: 16px;
  line-height: 1.85;
  letter-spacing: .04em;
  color: var(--about-silver-90);
}

.page-about .chapter__aside {
  min-width: 0;
  padding-left: 14px;
  border-left: 1px solid var(--about-hair);
}

.page-about .about-aside__note {
  margin: 12px 0 0;
  font-size: 13.5px;
  line-height: 1.8;
  letter-spacing: .04em;
  color: var(--silver-2);
}

/* ---------- 时间轴 ---------- */
.page-about .timeline {
  position: relative;
  margin: 22px 0 0;
  padding: 0 0 0 24px;
  list-style: none;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, transparent, var(--line) 12%, var(--line) 88%, transparent);
}

.page-about .timeline__item {
  position: relative;
  padding-bottom: 22px;
}

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

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -24px;
  top: 6px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--ink);
  border: 1px solid var(--gold);
}

.page-about .timeline__item:last-child::before {
  background: var(--cinnabar);
  border-color: var(--gold-hi);
  box-shadow: 0 0 0 3px rgba(200, 56, 46, .2);
}

.page-about .timeline__year {
  margin: 0;
  font-family: var(--font-num);
  font-size: 14px;
  letter-spacing: .12em;
  color: var(--gold);
}

.page-about .timeline__title {
  margin: 6px 0 0;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 800;
  letter-spacing: .03em;
  color: var(--silver);
}

.page-about .timeline__text {
  margin: 8px 0 0;
  max-width: 60ch;
  font-size: 15.5px;
  line-height: 1.85;
  letter-spacing: .04em;
  color: var(--about-silver-90);
}

/* ---------- 团队分工 ---------- */
.page-about .team-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .team-list__item {
  padding: 0 0 14px 14px;
  border-left: 1px solid var(--about-hair);
}

.page-about .team-list__item + .team-list__item {
  padding-top: 14px;
  border-top: 1px solid var(--about-hair-soft);
}

.page-about .team-list__name {
  margin: 0;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 800;
  letter-spacing: .03em;
  color: var(--gold-hi);
}

.page-about .team-list__desc {
  margin: 8px 0 0;
  font-size: 15.5px;
  line-height: 1.85;
  letter-spacing: .04em;
  color: var(--about-silver-90);
}

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

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--about-hair-soft);
}

.page-about .about-figure--wide {
  margin-top: 24px;
}

.page-about .about-figure--wide img {
  aspect-ratio: 4 / 3;
}

.page-about .about-figure__cap {
  margin: 10px 0 0;
  font-size: 13px;
  line-height: 1.75;
  letter-spacing: .04em;
  color: var(--silver-2);
}

/* ---------- 清单链路 ---------- */
.page-about .pipeline {
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .pipeline__step {
  position: relative;
  padding: 0 0 22px 52px;
}

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

.page-about .pipeline__step::before {
  content: "";
  position: absolute;
  left: 17px;
  top: 36px;
  bottom: 2px;
  width: 1px;
  background: var(--about-hair);
}

.page-about .pipeline__step:last-child::before {
  display: none;
}

.page-about .pipeline__num {
  position: absolute;
  left: 0;
  top: 0;
  width: 35px;
  height: 35px;
  display: grid;
  place-items: center;
  font-family: var(--font-num);
  font-size: 13px;
  color: var(--gold);
  background: var(--ink-2);
  border: 1px solid var(--line);
}

.page-about .pipeline__title {
  margin: 4px 0 0;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 800;
  letter-spacing: .03em;
  color: var(--silver);
}

.page-about .pipeline__text {
  margin: 8px 0 0;
  max-width: 60ch;
  font-size: 15.5px;
  line-height: 1.85;
  letter-spacing: .04em;
  color: var(--about-silver-90);
}

/* ---------- 首访评估 ---------- */
.page-about .checks {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .checks__item {
  padding: 16px 16px 16px 18px;
  border: 1px solid var(--about-hair-soft);
  border-left: 3px solid var(--gold);
  background: var(--ink-2);
}

.page-about .checks__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 800;
  letter-spacing: .04em;
  color: var(--gold-hi);
}

.page-about .checks__text {
  margin: 8px 0 0;
  font-size: 15px;
  line-height: 1.8;
  letter-spacing: .04em;
  color: var(--about-silver-90);
}

/* ---------- 内容边界 ---------- */
.page-about .scope {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin-top: 18px;
}

.page-about .scope__col {
  padding: 18px 16px;
}

.page-about .scope__col--do {
  background: var(--paper);
  border: 1px solid var(--paper);
  color: #23232B;
}

.page-about .scope__col--dont {
  background: linear-gradient(180deg, var(--blood), rgba(58, 20, 20, .3));
  border: 1px solid rgba(200, 56, 46, .5);
  color: var(--about-silver-90);
}

.page-about .scope__title {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 800;
  letter-spacing: .06em;
}

.page-about .scope__col--do .scope__title {
  color: #1B1B22;
}

.page-about .scope__col--dont .scope__title {
  color: var(--gold-hi);
}

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

.page-about .scope__list li {
  position: relative;
  padding: 0 0 12px 18px;
  font-size: 15px;
  line-height: 1.8;
  letter-spacing: .04em;
}

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

.page-about .scope__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 7px;
  height: 7px;
}

.page-about .scope__col--do .scope__list li::before {
  background: var(--cinnabar);
}

.page-about .scope__col--dont .scope__list li::before {
  border: 1px solid var(--cinnabar);
}

/* ---------- 生态与评审 ---------- */
.page-about .eco {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .eco__item {
  padding: 16px 16px 18px;
  border: 1px solid var(--about-hair-soft);
  border-top: 2px solid var(--line);
  background: var(--ink-2);
}

.page-about .eco__name {
  margin: 0;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 800;
  letter-spacing: .04em;
  color: var(--gold);
}

.page-about .eco__desc {
  margin: 8px 0 0;
  font-size: 15px;
  line-height: 1.8;
  letter-spacing: .04em;
  color: var(--about-silver-90);
}

/* ---------- 延伸入口 ---------- */
.page-about .about-next {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  margin-top: 18px;
}

.page-about .about-next__link {
  position: relative;
  display: block;
  min-height: 48px;
  padding: 15px 16px 28px;
  border: 1px solid var(--about-hair-soft);
  background: var(--ink-2);
  color: var(--silver);
  text-decoration: none;
  transition: border-color 240ms var(--ease), background-color 240ms var(--ease);
}

.page-about .about-next__link::after {
  content: "";
  position: absolute;
  left: 16px;
  right: 16px;
  bottom: 12px;
  height: 1px;
  background: var(--gold);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 240ms var(--ease);
}

.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  border-color: var(--gold);
  background: var(--ink-3);
}

.page-about .about-next__link:hover::after,
.page-about .about-next__link:focus-visible::after {
  transform: scaleX(1);
}

.page-about .about-next__label {
  display: block;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 800;
  letter-spacing: .04em;
  color: var(--gold-hi);
}

.page-about .about-next__note {
  display: block;
  margin-top: 6px;
  font-size: 13.5px;
  line-height: 1.7;
  letter-spacing: .04em;
  color: var(--silver-2);
}

.page-about .about-tail {
  margin: 22px 0 0;
  padding-top: 16px;
  border-top: 1px solid var(--about-hair-soft);
  max-width: 64ch;
  font-size: 14px;
  line-height: 1.85;
  letter-spacing: .04em;
  color: var(--silver-2);
}

/* ---------- 桌面端 ---------- */
@media (min-width: 760px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    max-width: 760px;
  }

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

  .page-about .scope {
    grid-template-columns: 1fr 1fr;
    gap: 18px;
  }

  .page-about .eco {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

@media (min-width: 900px) {
  .page-about .about-body {
    grid-template-columns: minmax(168px, 22%) minmax(0, 1fr);
    gap: clamp(30px, 4vw, 66px);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--bar-h) + 22px);
    align-self: start;
  }

  .page-about .about-rail__list {
    display: block;
    padding-bottom: 0;
    overflow: visible;
  }

  .page-about .about-rail__item + .about-rail__item {
    border-top: 1px solid var(--about-hair-soft);
  }

  .page-about .about-rail__link {
    width: 100%;
    white-space: normal;
  }

  .page-about .chapter__index {
    margin-left: -.1em;
  }

  .page-about .chapter__grid {
    grid-template-columns: minmax(0, 1fr) minmax(170px, 26%);
  }

  .page-about .about-figure--wide img {
    aspect-ratio: 16 / 9;
  }

  .page-about .checks__item {
    padding: 18px 18px 18px 20px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .about-next__link,
  .page-about .about-next__link::after,
  .page-about .about-rail__link::before {
    transition: opacity 200ms var(--ease);
  }

  .page-about .about-next__link::after {
    transform: none;
    opacity: 0;
  }

  .page-about .about-next__link:hover::after,
  .page-about .about-next__link:focus-visible::after {
    opacity: 1;
  }
}
<<<END>>>