.page-about {
  --about-flow-gap: clamp(72px, 9vw, 118px);
  --about-rail-w: 104px;
}

.page-about .about-shell {
  padding-block: clamp(22px, 3.6vw, 44px) clamp(56px, 8vw, 112px);
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-bottom: clamp(26px, 4vw, 48px);
}

.page-about .about-crumb .breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  margin-right: 10px;
  color: var(--mist);
  opacity: 0.5;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding-block: clamp(34px, 5.4vw, 74px) clamp(46px, 7vw, 88px);
  border-bottom: var(--line);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -32%;
  right: -20%;
  width: min(840px, 92vw);
  height: min(620px, 74vw);
  z-index: -2;
  pointer-events: none;
  background: linear-gradient(
    140deg,
    rgba(63, 224, 208, 0.17),
    rgba(154, 107, 255, 0.1) 46%,
    rgba(10, 18, 32, 0) 76%
  );
  clip-path: polygon(22% 0, 100% 0, 100% 76%, 0 100%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  opacity: 0.06;
  background-image: radial-gradient(circle, rgba(243, 239, 228, 0.9) 0.5px, transparent 0.5px);
  background-size: 3px 3px;
}

.page-about .about-hero__kicker {
  margin: 0 0 18px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.24em;
  color: var(--cyan);
}

.page-about .about-hero__title {
  margin: 0 0 clamp(20px, 3vw, 30px);
  max-width: 16em;
  font-family: var(--font-display);
  font-size: clamp(30px, 5.2vw, 62px);
  font-weight: 300;
  line-height: 1.18;
  letter-spacing: 0.06em;
  color: var(--paper);
}

.page-about .about-hero__lede {
  margin: 0 0 clamp(30px, 4.6vw, 50px);
  max-width: 34em;
  font-size: clamp(15px, 1.4vw, 18px);
  line-height: 1.9;
  color: var(--mist);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--edge);
  border: var(--line);
  box-shadow: var(--shadow-hard);
}

.page-about .about-hero__stats > li {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px 18px;
  background: var(--ink);
}

.page-about .about-hero__stat-num {
  font-family: var(--font-mono);
  font-size: clamp(22px, 3vw, 34px);
  font-weight: 600;
  line-height: 1.1;
  color: var(--amber);
}

.page-about .about-hero__stat-label {
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--mist);
  opacity: 0.8;
}

@media (min-width: 760px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 滚动主体：左刻度 + 右正文 ---------- */
.page-about .about-scroll {
  display: block;
}

.page-about .about-flow {
  display: flex;
  flex-direction: column;
  gap: var(--about-flow-gap);
  min-width: 0;
  padding-top: clamp(48px, 6vw, 84px);
}

@media (min-width: 1024px) {
  .page-about .about-scroll {
    display: grid;
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: clamp(24px, 3.4vw, 56px);
    align-items: start;
  }
}

/* ---------- 左侧年份刻度 ---------- */
.page-about .about-rail {
  display: none;
}

@media (min-width: 1024px) {
  .page-about .about-rail {
    display: block;
  }

  .page-about .about-rail__sticky {
    position: sticky;
    top: 96px;
    display: flex;
    flex-direction: column;
    gap: 18px;
  }
}

.page-about .about-rail__readout {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.22em;
  color: var(--amber);
}

.page-about .about-rail__scale {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 24px;
  margin: 0;
  padding: 0 0 0 16px;
  list-style: none;
}

.page-about .about-rail__scale::before {
  content: "";
  position: absolute;
  left: 3px;
  top: 6px;
  bottom: 6px;
  width: 2px;
  background: linear-gradient(180deg, var(--clay), rgba(43, 55, 70, 0.4));
}

.page-about .about-rail__item {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.page-about .about-rail__item::before {
  content: "";
  position: absolute;
  left: -17px;
  top: 6px;
  width: 8px;
  height: 8px;
  background: var(--clay);
  border-radius: 50%;
}

.page-about .about-rail__year {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--paper);
}

.page-about .about-rail__stage {
  font-size: 11px;
  line-height: 1.5;
  letter-spacing: 0.1em;
  color: var(--mist);
  opacity: 0.65;
}

/* ---------- 章节块 ---------- */
.page-about .about-block {
  position: relative;
  padding-block: clamp(6px, 1.6vw, 18px);
}

@media (min-width: 1024px) {
  .page-about .about-flow > .about-block:nth-of-type(even) {
    padding: clamp(28px, 3.6vw, 54px);
    background: linear-gradient(180deg, rgba(22, 32, 46, 0.92), rgba(22, 32, 46, 0.55));
    border: var(--line);
    box-shadow: var(--shadow-hard);
  }
}

.page-about .about-block__title {
  margin: 14px 0 18px;
  max-width: 20em;
  font-family: var(--font-display);
  font-size: clamp(24px, 3.2vw, 40px);
  font-weight: 400;
  line-height: 1.32;
  letter-spacing: 0.04em;
  color: var(--paper);
}

.page-about .about-block__lede {
  margin: 0 0 clamp(28px, 4vw, 48px);
  max-width: 34em;
  font-size: 16px;
  line-height: 1.9;
  color: var(--mist);
}

.page-about .about-block__more {
  margin: clamp(26px, 3.4vw, 40px) 0 0;
  max-width: 36em;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
  opacity: 0.85;
}

.page-about .about-block__more a {
  color: var(--cyan);
  border-bottom: 1px solid rgba(63, 224, 208, 0.4);
}

.page-about .about-block__more a:hover {
  border-bottom-color: var(--cyan);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
}

.page-about .about-timeline__list {
  position: relative;
  margin: 0;
  padding: 0 0 0 24px;
  list-style: none;
}

.page-about .about-timeline__list::before {
  content: "";
  position: absolute;
  left: 3px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: linear-gradient(180deg, var(--clay), rgba(43, 55, 70, 0.35));
}

.page-about .about-timeline__item {
  position: relative;
  padding-bottom: clamp(26px, 3.4vw, 40px);
}

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

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -25px;
  top: 8px;
  width: 8px;
  height: 8px;
  background: var(--clay);
}

.page-about .about-timeline__year {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--amber);
}

.page-about .about-timeline__item h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--paper);
}

.page-about .about-timeline__item p {
  margin: 0;
  max-width: 32em;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
}

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

@media (min-width: 860px) {
  .page-about .about-timeline {
    grid-template-columns: minmax(0, 1fr) 300px;
    align-items: start;
  }

  .page-about .about-timeline__figure {
    position: sticky;
    top: 100px;
  }
}

/* ---------- 三条主线：错层卡片 ---------- */
.page-about .about-lines {
  display: grid;
  gap: 20px;
}

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

.page-about .about-line__idx {
  position: absolute;
  top: 16px;
  right: 18px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.18em;
  color: var(--mist);
  opacity: 0.45;
}

@media (min-width: 900px) {
  .page-about .about-lines {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    gap: 24px;
  }

  .page-about .about-lines > :nth-child(1) {
    grid-column: 1 / 7;
  }

  .page-about .about-lines > :nth-child(2) {
    grid-column: 8 / 13;
    margin-top: 64px;
  }

  .page-about .about-lines > :nth-child(3) {
    grid-column: 3 / 9;
    margin-top: 12px;
  }
}

/* ---------- 团队分工带 ---------- */
.page-about .about-team__figure {
  margin: 0 0 clamp(26px, 3.4vw, 42px);
}

.page-about .about-team {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--edge);
  border: var(--line);
  box-shadow: var(--shadow-hard);
}

.page-about .about-team__cell {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: clamp(20px, 2.4vw, 30px);
  background: var(--ink);
  transition: background-color 240ms ease;
}

.page-about .about-team__cell:hover {
  background: var(--panel);
}

.page-about .about-team__num {
  font-family: var(--font-mono);
  font-size: clamp(30px, 4vw, 46px);
  font-weight: 600;
  line-height: 1;
  color: var(--amber);
}

.page-about .about-team__role {
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--paper);
}

.page-about .about-team__desc {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist);
  opacity: 0.85;
}

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

@media (min-width: 1080px) {
  .page-about .about-team {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 支撑节点 ---------- */
.page-about .about-nodes__figure {
  margin: 0 0 clamp(26px, 3.4vw, 42px);
}

.page-about .about-nodes {
  border-top: var(--line);
}

.page-about .about-nodes .ledger__row {
  display: grid;
  gap: 8px;
  padding: 20px 0;
  border-bottom: var(--line);
}

.page-about .about-nodes .ledger__key {
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--paper);
}

.page-about .about-nodes .ledger__key::before {
  content: "";
  display: inline-block;
  width: 18px;
  height: 2px;
  margin-right: 10px;
  vertical-align: middle;
  background: var(--clay);
}

.page-about .about-nodes .ledger__value {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
}

@media (min-width: 720px) {
  .page-about .about-nodes .ledger__row {
    grid-template-columns: 150px minmax(0, 1fr);
    gap: 28px;
    align-items: baseline;
  }
}

/* ---------- 档案编目 ---------- */
.page-about .about-catalog {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--edge);
  border: var(--line);
}

.page-about .about-catalog__step {
  padding: clamp(22px, 2.6vw, 36px);
  background: var(--ink);
}

.page-about .about-catalog__idx {
  display: block;
  margin-bottom: 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.24em;
  color: var(--amber);
}

.page-about .about-catalog__step h3 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--paper);
}

.page-about .about-catalog__step p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--mist);
}

@media (min-width: 860px) {
  .page-about .about-catalog {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 合作生态 ---------- */
.page-about .about-partners {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-partners__item {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: clamp(18px, 2.2vw, 26px);
  border: var(--line);
  background: rgba(22, 32, 46, 0.5);
  transition: border-color 240ms ease, background-color 240ms ease;
}

.page-about .about-partners__item:hover {
  border-color: var(--cyan);
  background: rgba(22, 32, 46, 0.85);
}

.page-about .about-partners__item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
}

@media (min-width: 760px) {
  .page-about .about-partners {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 响应节奏 ---------- */
.page-about .about-response {
  display: grid;
  gap: 1px;
  background: var(--edge);
  border-top: var(--line);
  border-bottom: var(--line);
}

.page-about .about-response__row {
  display: grid;
  gap: 8px;
  padding: 20px 0;
  background: var(--ink);
}

.page-about .about-response__key {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .about-response__val {
  margin: 0;
  max-width: 40em;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
}

@media (min-width: 760px) {
  .page-about .about-response__row {
    grid-template-columns: 130px minmax(0, 1fr);
    gap: 28px;
    align-items: baseline;
    padding: 22px 0;
  }
}

/* ---------- 结尾去向 ---------- */
.page-about .about-next {
  padding-top: clamp(16px, 3vw, 32px);
  border-top: var(--line);
}

.page-about .about-next__title {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-size: clamp(22px, 2.8vw, 32px);
  font-weight: 400;
  letter-spacing: 0.05em;
  color: var(--paper);
}

.page-about .about-next__text {
  margin: 0 0 clamp(22px, 3vw, 34px);
  max-width: 34em;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .about-next__actions {
  flex-wrap: wrap;
}

/* ---------- 图片容器统一 ---------- */
.page-about .media-frame img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}