.page-about {
  --about-index: 56px;
  --about-rule-accent: var(--blue);
  background: var(--ink);
  color: var(--paper);
  overflow-x: hidden;
}

@media (min-width: 900px) {
  .page-about {
    --about-index: 108px;
  }
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  padding: clamp(28px, 6vw, 76px) 0 clamp(32px, 5vw, 64px);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(53, 224, 208, .055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(53, 224, 208, .055) 1px, transparent 1px);
  background-size: 56px 56px;
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, .85), transparent 76%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, .85), transparent 76%);
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: -180px;
  right: -140px;
  width: 460px;
  height: 460px;
  background: radial-gradient(circle, rgba(228, 179, 60, .16), transparent 68%);
  pointer-events: none;
}

.page-about .about-hero .breadcrumbs {
  position: relative;
  z-index: 1;
  margin-bottom: clamp(24px, 4vw, 44px);
  font-size: 13px;
  color: var(--muted);
}

.page-about .about-hero .breadcrumbs a {
  color: var(--muted);
  text-decoration: none;
}

.page-about .about-hero .breadcrumbs a:hover {
  color: var(--gold);
}

.page-about .about-hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: clamp(22px, 4vw, 44px);
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, .88fr);
    align-items: end;
  }
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(30px, 5.4vw, 58px);
  line-height: 1.08;
  letter-spacing: .03em;
  color: var(--paper);
}

.page-about .about-hero__accent {
  display: block;
  margin-top: 10px;
  font-size: .56em;
  font-weight: 700;
  letter-spacing: .06em;
  color: var(--gold-soft);
}

.page-about .about-hero__side .lead {
  margin: 0 0 24px;
  max-width: 36em;
  font-size: clamp(16px, 1.6vw, 18px);
  line-height: 1.8;
  color: rgba(242, 245, 241, .82);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}

/* ---------- 长卷主体 ---------- */

.page-about .about-flow {
  padding: clamp(36px, 6vw, 84px) 0 clamp(48px, 8vw, 104px);
}

.page-about .about-sec {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  padding: clamp(30px, 5vw, 60px) 0;
  border-top: 1px solid var(--line);
}

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

@media (min-width: 900px) {
  .page-about .about-sec {
    grid-template-columns: var(--about-index) minmax(0, 1fr);
    gap: clamp(20px, 3vw, 48px);
  }
}

.page-about .about-sec__num {
  margin: 0;
  align-self: start;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: clamp(20px, 2.2vw, 26px);
  letter-spacing: .1em;
  color: var(--gold);
}

@media (min-width: 900px) {
  .page-about .about-sec__num {
    position: sticky;
    top: 132px;
  }
}

.page-about .about-sec__num::after {
  content: "";
  display: block;
  width: 1px;
  height: 42px;
  margin-top: 12px;
  background: linear-gradient(180deg, var(--gold), transparent);
}

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

.page-about .about-sec h2 {
  margin: 0 0 18px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(22px, 3vw, 34px);
  line-height: 1.28;
  letter-spacing: .03em;
  color: var(--gold-soft);
}

.page-about .about-sec__main p {
  margin: 0 0 16px;
  max-width: 42em;
  font-size: 16px;
  line-height: 1.8;
  color: rgba(242, 245, 241, .88);
}

.page-about .about-sec__tail {
  margin-top: 20px;
  font-size: 15px;
  color: var(--muted);
}

.page-about .about-sec__tail a {
  color: var(--gold);
  text-decoration: none;
  border-bottom: 1px solid rgba(228, 179, 60, .45);
}

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

/* ---------- 图片 ---------- */

.page-about .about-figure {
  margin: 26px 0 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--coal);
  max-width: 100%;
}

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

.page-about .about-figure figcaption {
  padding: 10px 14px;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .02em;
  color: var(--muted);
}

/* ---------- 版本长卷 ---------- */

.page-about .about-timeline {
  margin: 26px 0 8px;
}

.page-about .about-timeline .rail__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
}

.page-about .about-timeline .rail__title {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-timeline .rail__nav {
  display: flex;
  gap: 8px;
}

.page-about .about-timeline .rail__btn {
  width: 34px;
  height: 34px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--gold);
  font-family: var(--font-mono);
  font-size: 14px;
  cursor: pointer;
  transition: background-color .24s var(--ease), border-color .24s var(--ease);
}

.page-about .about-timeline .rail__btn:hover {
  background: rgba(228, 179, 60, .12);
  border-color: var(--gold);
}

.page-about .about-timeline__track {
  display: flex;
  gap: 14px;
  overflow-x: auto;
  padding: 6px 2px 16px;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
  scrollbar-color: var(--line) transparent;
}

.page-about .about-timeline__track::-webkit-scrollbar {
  height: 6px;
}

.page-about .about-timeline__track::-webkit-scrollbar-thumb {
  background: var(--line);
  border-radius: 3px;
}

.page-about .tl-node {
  position: relative;
  flex: 0 0 min(286px, 80vw);
  scroll-snap-align: start;
  padding: 22px 20px 24px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: transform .32s var(--ease), border-color .32s var(--ease);
}

.page-about .tl-node::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--gold), var(--cyan));
  opacity: .5;
}

.page-about .tl-node:hover,
.page-about .tl-node:focus-within {
  transform: translateY(-4px);
  border-color: rgba(228, 179, 60, .55);
}

.page-about .tl-node__dot {
  display: block;
  width: 10px;
  height: 10px;
  margin-bottom: 14px;
  border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 0 4px rgba(228, 179, 60, .16);
}

.page-about .tl-node__ver {
  display: block;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: .12em;
  color: var(--cyan);
}

.page-about .tl-node__title {
  margin: 8px 0 10px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--paper);
}

.page-about .tl-node__desc {
  margin: 0;
  max-width: none;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
  transition: color .3s var(--ease);
}

.page-about .tl-node:hover .tl-node__desc {
  color: rgba(242, 245, 241, .82);
}

/* ---------- 数据条 ---------- */

.page-about .about-facts {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  margin: 26px 0 6px;
}

@media (min-width: 620px) {
  .page-about .about-facts {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1100px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .about-fact {
  padding: 16px 16px 15px;
  background: rgba(76, 141, 255, .07);
  border-left: 2px solid var(--about-rule-accent);
}

.page-about .about-fact__val {
  display: block;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 21px;
  letter-spacing: .02em;
  color: var(--paper);
}

.page-about .about-fact__label {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .about-facts--cyan {
  margin-top: 20px;
}

.page-about .about-fact--cyan {
  background: rgba(53, 224, 208, .08);
  border-left-color: var(--cyan);
}

/* ---------- 团队档案卡 ---------- */

.page-about .team-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  margin: 24px 0 4px;
}

@media (min-width: 720px) {
  .page-about .team-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .team-card {
  position: relative;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: transform .3s var(--ease), border-color .3s var(--ease);
}

.page-about .team-card::after {
  content: "";
  position: absolute;
  inset: 5px;
  border: 1px dashed rgba(143, 163, 155, .16);
  border-radius: var(--radius);
  pointer-events: none;
}

.page-about .team-card:hover {
  transform: translateY(-4px);
  border-color: rgba(228, 179, 60, .5);
}

.page-about .team-card .fold__head {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  gap: 12px;
  width: 100%;
  padding: 18px 18px 16px;
  background: transparent;
  border: 0;
  text-align: left;
  cursor: pointer;
  font: inherit;
  color: inherit;
}

.page-about .team-card__name {
  flex: 1 1 auto;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  letter-spacing: .02em;
  color: var(--paper);
}

.page-about .team-card__count {
  flex: 0 0 auto;
  padding: 2px 8px;
  border: 1px solid rgba(76, 141, 255, .5);
  border-radius: var(--radius);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .04em;
  color: var(--blue);
}

.page-about .team-card .fold__icon {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 16px;
  line-height: 1;
  color: var(--gold);
}

.page-about .team-card .fold__body-inner {
  position: relative;
  z-index: 1;
  padding: 0 18px 18px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 分布点阵 ---------- */

.page-about .about-map-wrap {
  margin: 26px 0 8px;
  padding: 10px;
  background: linear-gradient(160deg, var(--card), var(--ink));
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

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

.page-about .map-dot {
  fill: var(--line);
}

.page-about .map-dot--hl {
  fill: var(--blue);
}

.page-about .map-label {
  fill: var(--muted);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .04em;
}

.page-about .map-label--end {
  fill: var(--cyan);
}

/* ---------- 更新节奏 ---------- */

.page-about .rhythm {
  margin: 24px 0 8px;
  border-top: 1px solid var(--line);
}

.page-about .rhythm__row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 4px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

@media (min-width: 720px) {
  .page-about .rhythm__row {
    grid-template-columns: 160px minmax(0, 1fr);
    gap: 24px;
    align-items: baseline;
  }
}

.page-about .rhythm__when {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: .1em;
  color: var(--gold);
}

.page-about .rhythm__what {
  font-size: 15px;
  line-height: 1.75;
  color: rgba(242, 245, 241, .86);
}

/* ---------- 合作方向 ---------- */

.page-about .coop-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  margin: 24px 0 6px;
}

@media (min-width: 780px) {
  .page-about .coop-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .coop-card {
  padding: 22px 20px 24px;
  background: var(--coal);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: border-color .3s var(--ease), transform .3s var(--ease);
}

.page-about .coop-card:hover {
  transform: translateY(-4px);
  border-color: rgba(53, 224, 208, .45);
}

.page-about .coop-card__idx {
  margin: 0 0 12px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .2em;
  color: var(--cyan);
}

.page-about .coop-card h3 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  letter-spacing: .03em;
  color: var(--gold-soft);
}

.page-about .coop-card p {
  margin: 0;
  max-width: none;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .about-cta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px 24px;
  margin-top: 32px;
  padding: 22px 22px;
  background: linear-gradient(120deg, rgba(228, 179, 60, .12), rgba(53, 224, 208, .07));
  border: 1px solid rgba(228, 179, 60, .3);
  border-radius: var(--radius);
}

.page-about .about-cta__text {
  margin: 0;
  flex: 1 1 220px;
  max-width: 34em;
  font-size: 15px;
  line-height: 1.7;
  color: rgba(242, 245, 241, .9);
}

/* ---------- 动效降级 ---------- */

@media (prefers-reduced-motion: reduce) {
  .page-about .tl-node,
  .page-about .team-card,
  .page-about .coop-card,
  .page-about .about-timeline .rail__btn {
    transition: none;
  }
  .page-about .tl-node:hover,
  .page-about .team-card:hover,
  .page-about .coop-card:hover {
    transform: none;
  }
}
</main>