.page-about {
  --about-line: rgba(26, 26, 26, 0.14);
  --about-line-soft: rgba(26, 26, 26, 0.08);
  --about-line-light: rgba(244, 241, 234, 0.18);
  background: var(--sand);
  color: var(--ink);
  overflow-x: clip;
}

.page-about .about-crumb {
  padding: calc(var(--topbar) + 18px) 0 18px;
  border-bottom: 1px solid var(--about-line-soft);
}

.page-about .about-crumb .breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--muted);
}

.page-about .about-crumb .breadcrumb li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--gold-deep);
}

.page-about .about-crumb .breadcrumb a {
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--about-line);
}

.page-about .about-crumb .breadcrumb a:hover {
  color: var(--gold-deep);
  border-bottom-color: var(--gold-deep);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  background: var(--ink);
  color: var(--sand);
  padding: clamp(36px, 7vw, 84px) 0 0;
  border-bottom: 3px solid var(--gold);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(244, 241, 234, 0.055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(244, 241, 234, 0.055) 1px, transparent 1px);
  background-size: 72px 72px;
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: -14%;
  top: -34%;
  width: min(560px, 78vw);
  aspect-ratio: 1;
  background: radial-gradient(circle, rgba(245, 166, 35, 0.3), rgba(245, 166, 35, 0) 62%);
  pointer-events: none;
}

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

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(26px, 5vw, 52px);
}

.page-about .about-hero .eyebrow {
  color: var(--gold);
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  font-size: clamp(30px, 7.4vw, 62px);
  line-height: 1.12;
  font-weight: 900;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-about .about-hero__lead {
  margin: 20px 0 0;
  max-width: 54ch;
  font-size: clamp(15px, 2.4vw, 17px);
  line-height: 1.8;
  color: rgba(244, 241, 234, 0.82);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.page-about .about-hero__fig {
  margin: 0;
  border-color: var(--about-line-light);
}

.page-about .about-hero__fig img {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .about-toc {
  position: relative;
  z-index: 1;
  margin-top: clamp(32px, 6vw, 60px);
  padding: 22px 0 26px;
  border-top: 1px solid var(--about-line-light);
}

.page-about .about-toc__title {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--gold);
}

.page-about .about-toc ol {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px 20px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-toc a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--about-line-light);
  color: rgba(244, 241, 234, 0.86);
  font-size: 14px;
  text-decoration: none;
  transition: color 180ms var(--ease), border-color 180ms var(--ease);
}

.page-about .about-toc a:hover,
.page-about .about-toc a:focus-visible {
  color: var(--gold);
  border-bottom-color: var(--gold);
}

.page-about .about-toc .mono {
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--gold-deep);
}

/* ---------- 章节骨架 ---------- */
.page-about .chapter {
  padding: clamp(46px, 8vw, 96px) 0;
  border-top: 1px solid var(--about-line);
}

.page-about .chapter--last {
  padding-bottom: clamp(50px, 8vw, 104px);
}

.page-about .chapter__grid {
  display: grid;
  gap: clamp(22px, 4vw, 36px);
}

.page-about .chapter__rail {
  display: flex;
  align-items: baseline;
  gap: 14px;
}

.page-about .chapter__num {
  font-size: clamp(30px, 7vw, 40px);
  font-weight: 700;
  line-height: 1;
  color: var(--gold);
}

.page-about .chapter__tag {
  font-family: var(--font-serif);
  font-size: 13px;
  letter-spacing: 0.28em;
  color: var(--muted);
}

.page-about .chapter__body h2 {
  margin: 12px 0 18px;
  font-size: clamp(23px, 4.6vw, 36px);
  line-height: 1.28;
  font-weight: 900;
  letter-spacing: -0.01em;
}

.page-about .chapter__body p {
  margin: 0 0 16px;
  max-width: 66ch;
  font-size: 16px;
  line-height: 1.85;
}

.page-about .chapter__body a {
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--gold);
  transition: color 160ms var(--ease), border-color 160ms var(--ease);
}

.page-about .chapter__body a:hover {
  color: var(--gold-deep);
  border-bottom-color: var(--gold-deep);
}

.page-about .chapter__aside {
  padding-left: 18px;
  border-left: 2px solid var(--gold);
}

.page-about .chapter__aside-label {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--gold-deep);
}

.page-about .chapter__aside-line {
  margin: 0 0 6px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.page-about .chapter__aside-line .mono {
  font-size: 18px;
  font-weight: 700;
  color: var(--ink);
  margin-right: 6px;
}

.page-about .chapter__aside-text {
  margin: 0 0 12px;
  font-family: var(--font-serif);
  font-size: 13.5px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .chapter__aside-text a {
  color: var(--blue);
  text-decoration: none;
  border-bottom: 1px solid rgba(42, 111, 151, 0.45);
}

.page-about .about-fig {
  margin: 0 0 14px;
}

.page-about .about-fig img {
  display: block;
  width: 100%;
  height: auto;
}

/* ---------- 要点列表 ---------- */
.page-about .about-points {
  list-style: none;
  margin: 24px 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .about-points li {
  position: relative;
  padding-left: 22px;
  font-size: 15.5px;
  line-height: 1.8;
  max-width: 62ch;
}

.page-about .about-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 12px;
  height: 2px;
  background: var(--gold);
}

.page-about .about-points strong {
  font-weight: 700;
  color: var(--ink);
}

/* ---------- 时间线 ---------- */
.page-about .timeline {
  list-style: none;
  margin: 26px 0 0;
  padding: 0 0 0 22px;
  border-left: 1px solid var(--rule);
  display: grid;
  gap: 20px;
}

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

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -28px;
  top: 9px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 0 3px var(--sand), 0 0 0 4px rgba(245, 166, 35, 0.45);
}

.page-about .timeline details > summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 12px;
  cursor: pointer;
  list-style: none;
  padding-right: 26px;
  position: relative;
}

.page-about .timeline details > summary::-webkit-details-marker {
  display: none;
}

.page-about .timeline details > summary::after {
  content: "+";
  position: absolute;
  right: 0;
  top: -2px;
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--gold-deep);
}

.page-about .timeline details[open] > summary::after {
  content: "−";
}

.page-about .timeline__year {
  font-size: 20px;
  font-weight: 700;
  color: var(--gold-deep);
  letter-spacing: 0.04em;
}

.page-about .timeline__title {
  font-size: 16.5px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--ink);
}

.page-about .timeline details[open] > summary {
  margin-bottom: 10px;
}

.page-about .timeline details > p {
  margin: 0;
  max-width: 62ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--ink-soft);
}

/* ---------- 会员三档 ---------- */
.page-about .tiers {
  list-style: none;
  margin: 26px 0 22px;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .tier {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 24px 20px 22px;
  background: var(--paper);
  border: 1px solid var(--about-line);
  border-radius: var(--radius);
}

.page-about .tier::before {
  content: "";
  position: absolute;
  top: 0;
  left: 20px;
  width: 44px;
  height: 3px;
  background: var(--gold);
}

.page-about .tier--deep {
  background: var(--ink);
  color: var(--sand);
  border-color: var(--ink);
}

.page-about .tier__name {
  margin: 8px 0 0;
  font-size: 19px;
  font-weight: 900;
  letter-spacing: 0.02em;
}

.page-about .tier--deep .tier__name {
  color: var(--gold);
}

.page-about .tier__for {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .tier--deep .tier__for {
  color: rgba(244, 241, 234, 0.66);
}

.page-about .tier__list {
  list-style: none;
  margin: 6px 0 0;
  padding: 0;
  display: grid;
  gap: 9px;
}

.page-about .tier__list li {
  position: relative;
  padding-left: 16px;
  font-size: 14.5px;
  line-height: 1.75;
}

.page-about .tier__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.68em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--gold-deep);
}

.page-about .tier--deep .tier__list li::before {
  background: var(--gold);
}

/* ---------- 团队分工 ---------- */
.page-about .crew {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 20px;
}

.page-about .crew__row {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: baseline;
  gap: 6px 14px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--about-line-soft);
}

.page-about .crew__role {
  font-size: 15.5px;
  font-weight: 700;
}

.page-about .crew__num {
  font-size: 22px;
  font-weight: 700;
  color: var(--gold-deep);
  line-height: 1;
}

.page-about .crew__track {
  grid-column: 1 / -1;
  display: block;
  height: 4px;
  background: rgba(26, 26, 26, 0.08);
  border-radius: 2px;
  overflow: hidden;
}

.page-about .crew__bar {
  display: block;
  height: 100%;
  width: var(--bar, 20%);
  background: linear-gradient(90deg, var(--gold-deep), var(--gold));
  border-radius: 2px;
}

.page-about .crew__desc {
  grid-column: 1 / -1;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 合作伙伴 ---------- */
.page-about .partners {
  list-style: none;
  margin: 26px 0 22px;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .partners li {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  column-gap: 12px;
  row-gap: 4px;
  padding: 16px 0;
  border-top: 1px solid var(--about-line);
}

.page-about .partners li:last-child {
  border-bottom: 1px solid var(--about-line);
}

.page-about .partners__idx {
  grid-row: span 2;
  font-size: 13px;
  font-weight: 700;
  color: var(--gold-deep);
  letter-spacing: 0.08em;
  align-self: start;
  padding-top: 3px;
}

.page-about .partners__name {
  font-size: 15.5px;
  font-weight: 700;
}

.page-about .partners__note {
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 节奏表 ---------- */
.page-about .cadence {
  margin: 26px 0 22px;
  border-top: 1px solid var(--about-line);
}

.page-about .cadence__row {
  display: grid;
  gap: 5px;
  padding: 15px 0;
  border-bottom: 1px solid var(--about-line);
}

.page-about .cadence__label {
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--gold-deep);
}

.page-about .cadence__text {
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--ink-soft);
}

.page-about .cadence__text a {
  color: var(--blue);
  text-decoration: none;
  border-bottom: 1px solid rgba(42, 111, 151, 0.45);
}

.page-about .about-region {
  margin-top: 20px;
  padding: 14px 16px;
  background: var(--gold-pale);
  border-left: 3px solid var(--gold);
  border-radius: 0 var(--radius) var(--radius) 0;
  font-size: 14px !important;
  line-height: 1.8;
  color: var(--ink);
  max-width: 72ch;
}

/* ---------- 结尾行动区 ---------- */
.page-about .about-cta {
  background: var(--ink);
  color: var(--sand);
  border-top: 3px solid var(--gold);
  padding: clamp(42px, 7vw, 84px) 0;
}

.page-about .about-cta__inner h2 {
  margin: 0 0 12px;
  font-size: clamp(22px, 5vw, 34px);
  line-height: 1.3;
  font-weight: 900;
  color: var(--white);
  max-width: 22ch;
}

.page-about .about-cta__inner p {
  margin: 0;
  max-width: 56ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: rgba(244, 241, 234, 0.8);
}

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

/* ---------- 响应式 ---------- */
@media (min-width: 560px) {
  .page-about .about-toc ol {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .page-about .tier--deep {
    grid-column: 1 / -1;
  }
}

@media (min-width: 760px) {
  .page-about .cadence__row {
    grid-template-columns: 168px minmax(0, 1fr);
    gap: 24px;
    align-items: baseline;
  }

  .page-about .partners li {
    grid-template-columns: 44px minmax(0, 1fr) minmax(0, 1.4fr);
    align-items: baseline;
    column-gap: 20px;
  }

  .page-about .partners__idx {
    grid-row: auto;
    padding-top: 0;
  }
}

@media (min-width: 900px) {
  .page-about .tiers {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .tier--deep {
    grid-column: auto;
  }

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

@media (min-width: 960px) {
  .page-about .about-crumb {
    padding-top: 26px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: end;
  }

  .page-about .about-toc ol {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }

  .page-about .chapter__grid {
    grid-template-columns: 86px minmax(0, 1fr) 250px;
    column-gap: clamp(26px, 4vw, 56px);
    align-items: start;
  }

  .page-about .chapter__rail {
    position: sticky;
    top: 96px;
    flex-direction: column;
    align-items: center;
    gap: 18px;
    align-self: start;
  }

  .page-about .chapter__tag {
    writing-mode: vertical-rl;
    letter-spacing: 0.34em;
    font-size: 12.5px;
  }

  .page-about .chapter__aside {
    position: sticky;
    top: 96px;
    align-self: start;
  }
}

@media (min-width: 1200px) {
  .page-about .chapter__grid {
    grid-template-columns: 96px minmax(0, 1fr) 280px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-toc a,
  .page-about .chapter__body a {
    transition: none;
  }
}
<<<END>>>

.page-about {
  --bar: 1rem;
}