.page-about {
  --about-toc-w: 208px;
  color: var(--ivory);
  background: var(--obsidian);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: 28px 0 52px;
  border-bottom: 1px solid var(--line-soft);
  background:
    radial-gradient(112% 92% at 84% -12%, rgba(212, 175, 55, .17), transparent 62%),
    radial-gradient(72% 62% at 4% 110%, rgba(47, 211, 196, .07), transparent 72%),
    var(--obsidian);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: 20px;
  right: -132px;
  width: 340px;
  height: 340px;
  border: 1px solid rgba(212, 175, 55, .18);
  border-radius: 50%;
  box-shadow: 0 0 0 46px rgba(212, 175, 55, .04);
  pointer-events: none;
}

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

.page-about .about-hero .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: 26px;
  font-size: 13px;
  color: var(--graphite);
}

.page-about .about-hero .breadcrumb a {
  color: var(--graphite);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

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

.page-about .about-hero .breadcrumb__sep {
  color: var(--mist);
}

.page-about .about-hero .eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--gold);
}

.page-about .about-hero .eyebrow::before {
  content: "";
  width: 26px;
  height: 1px;
  background: var(--gold);
}

.page-about .about-hero h1 {
  max-width: 16em;
  margin: 18px 0 0;
  font-size: clamp(31px, 7vw, 56px);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -0.025em;
  color: var(--ivory);
}

.page-about .about-hero .lede {
  max-width: 62ch;
  margin: 22px 0 0;
  font-size: 17px;
  line-height: 1.85;
  color: rgba(244, 239, 228, .78);
}

.page-about .about-figs {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 34px 0 0;
  padding: 0;
  list-style: none;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-figs li {
  padding: 17px 16px 19px;
  background: rgba(11, 12, 14, .74);
}

.page-about .about-figs__num {
  display: block;
  font-size: 24px;
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: .02em;
  color: var(--gold-light);
}

.page-about .about-figs__lab {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--graphite);
}

/* ---------- 主体骨架 ---------- */
.page-about .about-shell {
  padding-top: 34px;
  padding-bottom: 64px;
}

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

/* ---------- 纵向目录 ---------- */
.page-about .about-toc {
  margin-bottom: 26px;
}

.page-about .about-toc__label {
  display: block;
  margin: 0 0 10px;
  font-size: 11px;
  letter-spacing: .2em;
  color: var(--gold);
}

.page-about .about-toc__list {
  display: flex;
  gap: 6px;
  margin: 0;
  padding: 0 0 12px;
  list-style: none;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.page-about .about-toc__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-toc__link {
  display: flex;
  align-items: center;
  gap: 9px;
  min-height: 44px;
  padding: 6px 12px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  font-size: 13px;
  white-space: nowrap;
  text-decoration: none;
  color: var(--graphite);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .about-toc__link:hover,
.page-about .about-toc__link:focus-visible {
  color: var(--ivory);
  border-color: var(--line);
  background: var(--deep);
}

.page-about .about-toc__num {
  font-size: 11px;
  letter-spacing: .06em;
  color: var(--gold);
}

/* ---------- 章节通用 ---------- */
.page-about .about-sec {
  padding: 38px 0;
  border-top: 1px solid var(--line-soft);
  scroll-margin-top: 96px;
}

.page-about .about-sec__head {
  margin-bottom: 24px;
}

.page-about .about-sec__num {
  display: block;
  margin-bottom: 12px;
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--gold);
}

.page-about .about-sec__title {
  margin: 0;
  font-size: clamp(21px, 3.4vw, 30px);
  font-weight: 800;
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--ivory);
}

.page-about .about-sec__desc {
  max-width: 66ch;
  margin: 14px 0 0;
  font-size: 16px;
  line-height: 1.8;
  color: rgba(244, 239, 228, .74);
}

.page-about .about-p {
  max-width: 68ch;
  margin: 20px 0 0;
  font-size: 16px;
  line-height: 1.82;
  color: rgba(244, 239, 228, .76);
}

.page-about .about-p a {
  color: var(--gold-light);
  text-decoration: none;
  border-bottom: 1px solid var(--line);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

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

/* ---------- /01 四类服务 ---------- */
.page-about .about-offer {
  display: grid;
  gap: 12px;
}

.page-about .offer-card {
  position: relative;
  padding: 24px 22px 26px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(165deg, var(--deep) 0%, rgba(23, 26, 31, .55) 100%);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .offer-card::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 22px;
  width: 40px;
  height: 2px;
  background: var(--gold);
  transition: width var(--dur) var(--ease);
}

.page-about .offer-card:hover {
  border-color: var(--gold);
  transform: translateY(-2px);
}

.page-about .offer-card:hover::before {
  width: 96px;
}

.page-about .offer-card__num {
  display: block;
  font-size: 12px;
  letter-spacing: .16em;
  color: rgba(212, 175, 55, .7);
}

.page-about .offer-card__title {
  margin: 12px 0 8px;
  font-size: 19px;
  font-weight: 700;
  color: var(--ivory);
}

.page-about .offer-card__desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: rgba(244, 239, 228, .7);
}

/* ---------- /02 图文错位 ---------- */
.page-about .about-split {
  display: grid;
  gap: 26px;
  align-items: start;
}

.page-about .about-bullets {
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-bullets li {
  position: relative;
  padding-left: 22px;
  font-size: 16px;
  line-height: 1.78;
  color: rgba(244, 239, 228, .76);
}

.page-about .about-bullets li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: .66em;
  width: 7px;
  height: 7px;
  border: 1px solid var(--gold);
  transform: rotate(45deg);
}

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

.page-about .about-figure__frame {
  aspect-ratio: 3 / 2;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: linear-gradient(150deg, var(--deep-2) 0%, var(--obsidian) 100%);
}

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

.page-about .about-figure__cap {
  display: block;
  margin: 10px 0 0;
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--graphite);
}

/* ---------- /03 三组分工 ---------- */
.page-about .about-teams {
  display: grid;
  gap: 12px;
}

.page-about .team-panel {
  padding: 24px 22px 26px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    linear-gradient(180deg, rgba(212, 175, 55, .13) 0%, rgba(212, 175, 55, 0) 46%),
    var(--deep);
  transition: border-color var(--dur) var(--ease);
}

.page-about .team-panel:hover {
  border-color: var(--gold);
}

.page-about .team-panel__role {
  display: block;
  font-size: 12px;
  letter-spacing: .16em;
  color: rgba(212, 175, 55, .75);
}

.page-about .team-panel__title {
  margin: 12px 0 10px;
  font-size: 18px;
  font-weight: 700;
  color: var(--ivory);
}

.page-about .team-panel__desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: rgba(244, 239, 228, .7);
}

.page-about .about-teams-figure {
  max-width: 760px;
  margin-top: 16px;
}

.page-about .about-teams-figure .about-figure__frame {
  aspect-ratio: 10 / 7;
}

/* ---------- /04 版本时间线 ---------- */
.page-about .about-timeline {
  display: grid;
  gap: 24px;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .tl-node {
  position: relative;
  padding-top: 22px;
  border-top: 1px solid var(--line);
}

.page-about .tl-node::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, var(--gold) 0%, rgba(212, 175, 55, 0) 88%);
  transform: scaleX(.38);
  transform-origin: left center;
  transition: transform 320ms var(--ease);
}

.page-about .tl-node:hover::before,
.page-about .tl-node:focus-within::before {
  transform: scaleX(1);
}

.page-about .tl-node__era {
  display: block;
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--gold);
}

.page-about .tl-node__title {
  margin: 10px 0 8px;
  font-size: 18px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ivory);
  transition: color var(--dur) var(--ease);
}

.page-about .tl-node:hover .tl-node__title {
  color: var(--gold-light);
}

.page-about .tl-node__desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: rgba(244, 239, 228, .7);
}

.page-about .about-tl-figure {
  max-width: 420px;
  margin-top: 32px;
}

.page-about .about-tl-figure .about-figure__frame {
  aspect-ratio: 1 / 1;
}

/* ---------- /05 更新节奏 ---------- */
.page-about .about-cadence {
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line-soft);
}

.page-about .about-cadence li {
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr);
  gap: 14px;
  align-items: baseline;
  padding: 16px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-cadence__when {
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--gold);
}

.page-about .about-cadence__what {
  font-size: 15.5px;
  line-height: 1.78;
  color: rgba(244, 239, 228, .78);
}

.page-about .about-cadence__what b {
  font-weight: 600;
  color: var(--ivory);
}

.page-about .about-cadence__what a {
  color: var(--gold-light);
  text-decoration: none;
  border-bottom: 1px solid var(--line);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

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

/* ---------- /06 共建伙伴 ---------- */
.page-about .about-partners {
  display: grid;
  gap: 12px;
}

.page-about .partner-card {
  padding: 24px 22px 26px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(23, 26, 31, .72);
  transition: border-color var(--dur) var(--ease);
}

.page-about .partner-card:hover {
  border-color: var(--gold);
}

.page-about .partner-card .tag {
  display: inline-block;
  margin-bottom: 14px;
}

.page-about .partner-card__title {
  margin: 0 0 10px;
  font-size: 18px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ivory);
}

.page-about .partner-card__desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: rgba(244, 239, 228, .7);
}

/* ---------- /07 站点信息 ---------- */
.page-about .about-meta {
  display: grid;
  gap: 10px;
  margin-top: 20px;
  padding: 20px 22px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: rgba(23, 26, 31, .5);
}

.page-about .about-meta__row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 14px;
  font-size: 14px;
  line-height: 1.7;
  color: rgba(244, 239, 228, .76);
}

.page-about .about-meta__key {
  min-width: 76px;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--gold);
}

/* ---------- 收束 ---------- */
.page-about .about-end {
  margin-top: 10px;
  padding-top: 38px;
}

.page-about .about-end__rule {
  display: block;
  height: 1px;
  background: linear-gradient(90deg, var(--gold) 0%, rgba(212, 175, 55, .06) 62%, rgba(212, 175, 55, 0) 100%);
}

.page-about .about-end__lead {
  margin: 26px 0 18px;
  font-size: clamp(19px, 2.8vw, 25px);
  font-weight: 800;
  line-height: 1.34;
  letter-spacing: -0.01em;
  color: var(--ivory);
}

.page-about .about-end__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 700px) {
  .page-about .about-hero {
    padding: 44px 0 68px;
  }

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

  .page-about .about-teams {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
  }

  .page-about .about-partners {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }

  .page-about .about-cadence li {
    grid-template-columns: 104px minmax(0, 1fr);
    gap: 24px;
  }

  .page-about .about-figs {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 860px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
    gap: 44px;
    align-items: center;
  }
}

@media (min-width: 940px) {
  .page-about .about-timeline {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 30px;
  }
}

@media (min-width: 1000px) {
  .page-about .about-shell {
    display: grid;
    grid-template-columns: var(--about-toc-w) minmax(0, 1fr);
    gap: 64px;
    padding-top: 56px;
    padding-bottom: 88px;
  }

  .page-about .about-toc {
    position: sticky;
    top: 88px;
    align-self: start;
    margin-bottom: 0;
  }

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

  .page-about .about-toc__list li + li {
    margin-top: 2px;
  }

  .page-about .about-toc__link {
    border: 0;
    border-left: 2px solid var(--mist);
    border-radius: 0;
    padding: 10px 12px 10px 14px;
    background: transparent;
  }

  .page-about .about-toc__link:hover,
  .page-about .about-toc__link:focus-visible {
    border-left-color: var(--gold);
    background: linear-gradient(90deg, rgba(212, 175, 55, .13), rgba(212, 175, 55, 0) 78%);
    color: var(--ivory);
  }

  .page-about .about-sec {
    padding: 56px 0;
  }

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