.page-about {
  --about-rail: 220px;
  --about-prose: 680px;
  --about-gap: 64px;
  --about-pad: 22px;
  background: var(--night);
  color: var(--paper);
  font-family: var(--font-body);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: 26px 0 48px;
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(120% 90% at 88% 8%, rgba(14, 42, 58, .85) 0%, rgba(11, 31, 26, 0) 62%),
    var(--night);
}

.page-about .breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--moss);
}

.page-about .breadcrumb a {
  color: var(--moss);
  text-decoration: none;
}

.page-about .breadcrumb a:hover {
  color: var(--volt);
}

.page-about .breadcrumb__sep {
  color: rgba(159, 178, 166, .55);
}

.page-about .about-hero__grid {
  display: grid;
  gap: 36px;
  margin-top: 30px;
}

.page-about .about-hero__lead .eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .22em;
  color: var(--volt);
}

.page-about .about-hero__lead .display-1 {
  margin: 14px 0 20px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(46px, 11vw, 96px);
  line-height: .95;
  letter-spacing: -.015em;
  color: var(--paper);
}

.page-about .about-hero__lead .lede {
  max-width: 46ch;
  margin: 0;
  font-size: 16px;
  line-height: 1.75;
  color: var(--moss);
}

/* 版本刻度条 */
.page-about .about-strip {
  position: relative;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  margin: 0 0 26px;
  padding: 0;
  list-style: none;
}

.page-about .about-strip::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 5px;
  height: 1px;
  background: var(--line-strong);
}

.page-about .about-strip__item {
  position: relative;
  padding-top: 20px;
}

.page-about .about-strip__item::before {
  content: "";
  position: absolute;
  top: 1px;
  left: 0;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--night);
  border: 1px solid var(--moss);
}

.page-about .about-strip__item.is-current::before {
  background: var(--volt);
  border-color: var(--volt);
}

.page-about .about-strip__year {
  display: block;
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .about-strip__item.is-current .about-strip__year {
  color: var(--volt);
}

.page-about .about-strip__note {
  display: block;
  margin-top: 4px;
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--moss);
}

/* 首屏指标 */
.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-hero__stat {
  padding: 16px 12px;
  background: var(--turf);
}

.page-about .about-hero__stat dt {
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--moss);
}

.page-about .about-hero__stat dd {
  margin: 8px 0 0;
  font-family: var(--font-mono);
  font-size: clamp(22px, 5vw, 32px);
  font-weight: 700;
  letter-spacing: -.02em;
  color: var(--volt);
}

.page-about .about-hero__stat dd em {
  font-style: normal;
  font-size: .6em;
  color: rgba(214, 255, 63, .7);
}

/* ---------- 文档骨架 ---------- */
.page-about .about-doc {
  padding: 40px 0 56px;
}

.page-about .about-doc__grid {
  display: grid;
  gap: 28px;
}

/* 章节目录 */
.page-about .about-toc__title {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .22em;
  color: var(--moss);
}

.page-about .about-toc__list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-toc__link {
  display: block;
  padding: 6px 10px;
  border: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--moss);
  text-decoration: none;
  white-space: nowrap;
}

.page-about .about-toc__link:hover {
  color: var(--night);
  background: var(--volt);
  border-color: var(--volt);
}

/* ---------- 章节卡 ---------- */
.page-about .about-chapter {
  position: relative;
  margin-bottom: 22px;
  padding: 28px var(--about-pad) 32px;
  border: 1px solid var(--line-ink);
}

.page-about .about-chapter--paper {
  background: var(--paper);
  color: var(--ink);
  box-shadow: 5px 5px 0 rgba(14, 42, 58, .55);
}

.page-about .about-chapter--deep {
  background: var(--turf);
  color: var(--paper);
  border-color: var(--line);
}

.page-about .about-chapter--blue {
  background: var(--blue);
  color: var(--paper);
  border-color: var(--line);
}

.page-about .about-chapter__head {
  padding-bottom: 16px;
  margin-bottom: 20px;
  border-bottom: 1px solid var(--line-ink);
}

.page-about .about-chapter--deep .about-chapter__head,
.page-about .about-chapter--blue .about-chapter__head {
  border-bottom-color: var(--line);
}

.page-about .tally {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .26em;
  color: var(--orange);
}

.page-about .about-chapter--deep .tally,
.page-about .about-chapter--blue .tally {
  color: var(--volt);
}

.page-about .about-chapter__head .h-section {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(26px, 6.4vw, 38px);
  line-height: 1.15;
  letter-spacing: -.01em;
}

.page-about .about-chapter__lede {
  margin: 12px 0 0;
  max-width: var(--about-prose);
  font-size: 15px;
  line-height: 1.7;
  opacity: .78;
}

.page-about .about-chapter__text {
  max-width: var(--about-prose);
}

.page-about .about-chapter__text p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.75;
}

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

.page-about .about-sub {
  margin: 24px 0 10px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 20px;
  line-height: 1.3;
}

.page-about .about-linkline {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 24px 0 0;
}

/* ---------- 版本节点 ---------- */
.page-about .about-era-jump {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
}

.page-about .about-era-jump a {
  padding: 6px 10px;
  border: 1px solid var(--line-ink);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--ink);
  text-decoration: none;
}

.page-about .about-era-jump a:hover {
  background: var(--ink);
  color: var(--paper);
}

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

.page-about .about-era__item {
  position: relative;
  padding: 0 0 24px 24px;
  border-left: 1px solid var(--line-ink);
}

.page-about .about-era__item:last-child {
  padding-bottom: 0;
  border-left-color: transparent;
}

.page-about .about-era__item::before {
  content: "";
  position: absolute;
  left: -4px;
  top: 5px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--paper);
  border: 2px solid var(--orange);
}

.page-about .about-era__item.is-current::before {
  background: var(--ink);
  border-color: var(--ink);
}

.page-about .about-era__version {
  display: inline-block;
  margin-bottom: 8px;
  padding: 3px 8px;
  border: 1px solid var(--line-ink);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--ink);
}

.page-about .about-era__item.is-current .about-era__version {
  background: var(--ink);
  color: var(--paper);
  border-color: var(--ink);
}

.page-about .about-era__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 20px;
  line-height: 1.3;
}

.page-about .about-era__item p {
  margin: 0;
  max-width: var(--about-prose);
  font-size: 15.5px;
  line-height: 1.75;
  opacity: .88;
}

/* ---------- 配图 ---------- */
.page-about .about-figure {
  margin: 22px 0 26px;
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--night);
}

.page-about .about-chapter--paper .about-figure {
  border-color: var(--line-ink);
}

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

/* ---------- 出品流程 ---------- */
.page-about .about-flow {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: step;
}

.page-about .about-flow__item {
  position: relative;
  margin-left: 12px;
  padding: 0 0 22px 26px;
  border-left: 1px solid var(--line-strong);
}

.page-about .about-flow__item:last-child {
  padding-bottom: 0;
  border-left-color: transparent;
}

.page-about .about-flow__item::before {
  counter-increment: step;
  content: "0" counter(step);
  position: absolute;
  left: -13px;
  top: -2px;
  width: 25px;
  height: 25px;
  display: grid;
  place-items: center;
  background: var(--night);
  border: 1px solid var(--line-strong);
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 700;
  color: var(--volt);
}

.page-about .about-flow__title {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 19px;
  line-height: 1.3;
  color: var(--paper);
}

.page-about .about-flow__desc {
  margin: 0 0 8px;
  max-width: var(--about-prose);
  font-size: 15px;
  line-height: 1.7;
  color: var(--moss);
}

.page-about .about-flow__time {
  display: inline-block;
  padding: 3px 8px;
  border: 1px solid rgba(255, 90, 43, .5);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .04em;
  color: var(--orange);
}

.page-about .about-chapter--deep .about-chapter__text {
  margin-top: 24px;
  color: var(--moss);
}

/* ---------- 团队分工 ---------- */
.page-about .about-team {
  display: grid;
  gap: 1px;
  background: var(--line-ink);
  border: 1px solid var(--line-ink);
}

.page-about .about-team__cell {
  padding: 18px 16px;
  background: var(--paper);
}

.page-about .about-team__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--ink);
}

.page-about .about-team__role {
  margin: 8px 0 8px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 18px;
  color: var(--ink);
}

.page-about .about-team__cell p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.7;
  color: rgba(26, 20, 16, .78);
}

/* ---------- 覆盖范围 ---------- */
.page-about .about-map {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(76px, 1fr));
  gap: 6px;
  margin-bottom: 26px;
}

.page-about .about-map__cell {
  padding: 11px 4px;
  border: 1px solid var(--line);
  background: rgba(242, 234, 216, .04);
  text-align: center;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--moss);
  transition: color .18s ease, border-color .18s ease, background .18s ease;
}

.page-about .about-map__cell:hover {
  color: var(--volt);
  border-color: var(--volt);
  background: rgba(214, 255, 63, .1);
}

.page-about .about-chapter--blue .about-chapter__text {
  color: rgba(242, 234, 216, .88);
}

/* ---------- 行业参与 ---------- */
.page-about .about-doing {
  display: grid;
  gap: 20px;
}

.page-about .about-doing__item {
  padding-left: 16px;
  border-left: 3px solid var(--orange);
}

.page-about .about-doing__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 20px;
  line-height: 1.3;
  color: var(--ink);
}

.page-about .about-doing__item p {
  margin: 0;
  max-width: var(--about-prose);
  font-size: 15.5px;
  line-height: 1.75;
  color: rgba(26, 20, 16, .82);
}

/* ---------- 来年重点 ---------- */
.page-about .about-next {
  display: grid;
  gap: 14px;
}

.page-about .about-next__item {
  position: relative;
  padding: 18px 16px 18px 18px;
  border: 1px solid var(--line);
  background: rgba(11, 31, 26, .5);
}

.page-about .about-next__idx {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .24em;
  color: var(--orange);
}

.page-about .about-next__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 20px;
  line-height: 1.3;
  color: var(--paper);
}

.page-about .about-next__item p {
  margin: 0;
  max-width: var(--about-prose);
  font-size: 15px;
  line-height: 1.72;
  color: var(--moss);
}

.page-about .about-chapter--deep .about-linkline .btn--ghost {
  color: var(--paper);
  border-color: var(--line-strong);
}

/* ---------- 结尾入口 ---------- */
.page-about .about-outro {
  padding: 26px var(--about-pad) 28px;
  border: 1px solid var(--line);
  background: linear-gradient(160deg, var(--blue) 0%, var(--night) 78%);
}

.page-about .about-outro__title {
  margin: 0 0 20px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(24px, 6vw, 34px);
  line-height: 1.2;
  color: var(--paper);
}

.page-about .about-outro__grid {
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-outro__link {
  display: block;
  padding: 16px 14px;
  background: var(--night);
  text-decoration: none;
  transition: background .18s ease;
}

.page-about .about-outro__link:hover {
  background: var(--turf);
}

.page-about .about-outro__label {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--volt);
}

.page-about .about-outro__desc {
  display: block;
  margin-top: 6px;
  font-size: 14px;
  line-height: 1.65;
  color: var(--moss);
}

.page-about .about-outro__foot {
  margin: 20px 0 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--moss);
}

.page-about .about-outro__foot a {
  color: var(--volt);
  text-decoration: none;
  border-bottom: 1px solid rgba(214, 255, 63, .45);
}

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

/* ---------- 平板 ---------- */
@media (min-width: 700px) {
  .page-about .about-hero {
    padding: 34px 0 58px;
  }

  .page-about .about-chapter {
    padding: 36px 30px 40px;
  }

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

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

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 40px 0 68px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: 5fr 7fr;
    gap: 56px;
    align-items: end;
  }

  .page-about .about-doc {
    padding: 56px 0 76px;
  }

  .page-about .about-doc__grid {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: var(--about-gap);
    justify-content: center;
  }

  .page-about .about-toc {
    position: sticky;
    top: 72px;
    align-self: start;
  }

  .page-about .about-toc__list {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 0;
  }

  .page-about .about-toc__link {
    padding: 8px 0 8px 12px;
    border: 0;
    border-left: 2px solid var(--line);
    letter-spacing: .06em;
  }

  .page-about .about-toc__link:hover {
    background: transparent;
    color: var(--volt);
    border-left-color: var(--volt);
  }

  .page-about .about-chapter {
    padding: 40px 40px 46px;
    margin-bottom: 26px;
  }

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

  .page-about .about-doing {
    gap: 26px;
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about .about-map__cell,
  .page-about .about-outro__link {
    transition: none;
  }
}