.page-about {
  --about-gap: clamp(20px, 3vw, 36px);
  --tl-pad: clamp(20px, 3vw, 36px);
  background-color: var(--c-night);
  color: var(--c-cream);
}

/* ============ 面包屑 ============ */
.page-about .breadcrumb {
  margin: 0 0 clamp(22px, 3.4vw, 36px);
}

/* ============ 首屏 ============ */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(26px, 4.6vw, 58px) 0 clamp(38px, 6vw, 84px);
  border-bottom: 1px solid var(--c-line);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -34%;
  right: -20%;
  width: min(660px, 80vw);
  height: min(660px, 80vw);
  background: radial-gradient(circle, rgba(62, 107, 79, .40) 0%, rgba(14, 27, 42, .20) 46%, transparent 72%);
  pointer-events: none;
  z-index: 0;
}

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

.page-about .hero-grid {
  display: grid;
  gap: clamp(28px, 5vw, 56px);
}

.page-about .about-hero__title {
  margin: 12px 0 0;
  font-family: var(--font-sans);
  font-size: clamp(30px, 5.2vw, 62px);
  line-height: 1.1;
  font-weight: 800;
  letter-spacing: -.012em;
  color: var(--c-flood);
}

.page-about .about-hero__lede {
  margin: 20px 0 0;
  max-width: 64ch;
  color: var(--c-sage);
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.9;
}

.page-about .about-hero__actions {
  margin-top: clamp(24px, 3.4vw, 34px);
}

.page-about .hero-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--r);
  overflow: hidden;
}

.page-about .hero-stats__cell {
  background: var(--c-ink);
  padding: clamp(16px, 2.4vw, 24px);
}

.page-about .hero-stats__value {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(24px, 3.2vw, 38px);
  line-height: 1;
  font-weight: 700;
  letter-spacing: -.03em;
  color: var(--c-lime);
}

.page-about .hero-stats__cell:nth-child(2) .hero-stats__value { color: var(--c-cream); }
.page-about .hero-stats__cell:nth-child(3) .hero-stats__value { color: var(--c-gold); }
.page-about .hero-stats__cell:nth-child(4) .hero-stats__value { color: var(--c-flood); }

.page-about .hero-stats__label {
  display: block;
  margin-top: 9px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--c-sage);
  letter-spacing: .02em;
}

@media (min-width: 980px) {
  .page-about .hero-grid {
    grid-template-columns: minmax(0, 1.32fr) minmax(290px, .88fr);
    align-items: end;
  }
}

/* ============ 章节头部 ============ */
.page-about .section__head {
  display: grid;
  gap: 14px;
  align-items: end;
  margin-bottom: clamp(26px, 3.6vw, 44px);
}

.page-about .section__lead {
  margin: 0;
  color: var(--c-sage);
  font-size: 15px;
  line-height: 1.85;
}

.page-about .section--ink {
  background-color: var(--c-ink);
}

@media (min-width: 880px) {
  .page-about .section__head {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr);
    gap: clamp(24px, 4vw, 56px);
  }
}

/* ============ 时间线 ============ */
.page-about .tl {
  list-style: none;
  margin: clamp(28px, 4vw, 48px) 0 0;
  padding: 0 0 0 var(--tl-pad);
  position: relative;
}

.page-about .tl::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, var(--c-lime) 0%, var(--c-moss) 24%, var(--c-line-strong) 100%);
}

.page-about .tl__item {
  position: relative;
  display: grid;
  gap: 14px;
  padding-bottom: clamp(32px, 4.8vw, 58px);
}

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

.page-about .tl__item::before {
  content: "";
  position: absolute;
  left: calc(-1 * var(--tl-pad) - 4px);
  top: 10px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--c-rock);
  border: 1px solid var(--c-sage);
  transition: background .45s var(--ease), border-color .45s var(--ease), box-shadow .45s var(--ease);
}

.page-about .tl__item.is-visible::before {
  background: var(--c-lime);
  border-color: var(--c-lime);
  box-shadow: 0 0 0 5px rgba(200, 255, 77, .14);
}

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

.page-about .tl__year {
  font-family: var(--font-mono);
  font-size: clamp(30px, 4.6vw, 46px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.04em;
  color: var(--c-sage);
  transition: color .45s var(--ease);
}

.page-about .tl__item.is-visible .tl__year {
  color: var(--c-lime);
}

.page-about .tl__stage {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--c-gold);
  border: 1px solid rgba(214, 163, 74, .40);
  border-radius: 999px;
  padding: 3px 10px;
}

.page-about .tl__body {
  border-top: 1px solid var(--c-line);
  padding-top: 16px;
}

.page-about .tl__title {
  margin: 0 0 10px;
  font-size: clamp(17px, 2vw, 21px);
  font-weight: 700;
  line-height: 1.5;
  color: var(--c-flood);
}

.page-about .tl__text {
  margin: 0;
  max-width: 64ch;
  font-size: 15px;
  line-height: 1.9;
  color: var(--c-sage);
}

@media (min-width: 860px) {
  .page-about .tl__item {
    grid-template-columns: 186px minmax(0, 1fr);
    gap: clamp(24px, 4vw, 56px);
  }

  .page-about .tl__axis {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
  }

  .page-about .tl__body {
    padding-top: 0;
    border-top: 0;
  }
}

/* ============ 图片容器 ============ */
.page-about .media {
  margin: 18px 0 0;
}

.page-about .media__frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--c-line);
  border-radius: var(--r);
  background: var(--c-night);
}

.page-about .media__frame::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(143, 163, 154, .07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(143, 163, 154, .07) 1px, transparent 1px);
  background-size: 34px 34px;
  pointer-events: none;
}

.page-about .media__frame--heat::after {
  background-image:
    radial-gradient(circle at 30% 68%, rgba(181, 101, 74, .34) 0%, transparent 42%),
    radial-gradient(circle at 68% 34%, rgba(200, 255, 77, .18) 0%, transparent 40%);
  background-size: auto;
}

.page-about .media__frame--map::after {
  background-image:
    linear-gradient(rgba(143, 163, 154, .10) 1px, transparent 1px),
    linear-gradient(90deg, rgba(143, 163, 154, .10) 1px, transparent 1px);
  background-size: 48px 48px;
}

.page-about .media__img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(.92) contrast(1.06) brightness(.94);
}

.page-about .media__caption {
  margin-top: 12px;
  padding-left: 12px;
  border-left: 2px solid var(--c-clay);
  font-size: 13px;
  line-height: 1.75;
  color: var(--c-sage);
}

.page-about .tl__media {
  margin-top: 20px;
  max-width: 720px;
}

/* ============ 团队与更新机制 ============ */
.page-about .team-split {
  display: grid;
  gap: clamp(28px, 4.5vw, 56px);
}

.page-about .team-split__media .media {
  margin-top: 0;
}

.page-about .team-split__body .headline {
  margin: 10px 0 18px;
}

.page-about .team-split__body .prose {
  color: var(--c-sage);
  line-height: 1.9;
}

@media (min-width: 960px) {
  .page-about .team-split {
    grid-template-columns: minmax(0, .92fr) minmax(0, 1.08fr);
    align-items: start;
    gap: clamp(36px, 5vw, 72px);
  }

  .page-about .team-split__media {
    position: sticky;
    top: 92px;
  }
}

.page-about .steps {
  list-style: none;
  margin: clamp(24px, 3vw, 34px) 0 0;
  padding: 0;
  border-top: 1px solid var(--c-line);
}

.page-about .steps__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 14px;
  padding: 18px 0;
  border-bottom: 1px solid var(--c-line);
}

.page-about .steps__num {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .08em;
  color: var(--c-lime);
  padding-top: 4px;
}

.page-about .steps__title {
  margin: 0 0 6px;
  font-size: 16px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--c-flood);
}

.page-about .steps__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--c-sage);
}

/* ============ 标签页 ============ */
.page-about .tabs__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding-bottom: 18px;
  margin-bottom: clamp(20px, 3vw, 30px);
  border-bottom: 1px solid var(--c-line);
}

.page-about .tabs__tab {
  appearance: none;
  font: inherit;
  font-size: 14px;
  letter-spacing: .02em;
  padding: 10px 16px;
  cursor: pointer;
  background: transparent;
  color: var(--c-sage);
  border: 1px solid var(--c-line-strong);
  border-radius: var(--r);
  transition: color .2s var(--ease), border-color .2s var(--ease), background-color .2s var(--ease);
}

.page-about .tabs__tab:hover {
  color: var(--c-cream);
  border-color: var(--c-lime);
}

.page-about .tabs__tab[aria-selected="true"] {
  background-color: var(--c-lime);
  border-color: var(--c-lime);
  color: var(--c-night);
  font-weight: 700;
}

.page-about .tabs__tab:focus-visible {
  outline: 2px solid var(--c-lime);
  outline-offset: 2px;
}

.page-about .tabs__panel[hidden] {
  display: none;
}

.page-about .tabs__panel:focus-visible {
  outline: 1px solid var(--c-lime);
  outline-offset: 6px;
}

.page-about .divide-list {
  margin: 0;
  border-top: 1px solid var(--c-line);
}

.page-about .divide-item {
  display: grid;
  gap: 4px;
  padding: 16px 0;
  border-bottom: 1px solid var(--c-line);
}

.page-about .divide-item__key {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--c-gold);
}

.page-about .divide-item__val {
  font-size: 15px;
  line-height: 1.8;
  color: var(--c-cream);
}

@media (min-width: 780px) {
  .page-about .divide-item {
    grid-template-columns: 168px minmax(0, 1fr);
    gap: 20px;
    align-items: baseline;
  }

  .page-about .divide-item__key {
    padding-top: 3px;
  }
}

/* ============ 专家专栏 ============ */
.page-about .columnists {
  display: grid;
  gap: clamp(26px, 4vw, 48px);
}

.page-about .columnists__lead .prose {
  margin-top: 16px;
  color: var(--c-sage);
  line-height: 1.9;
}

.page-about .topic-list {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  align-content: start;
}

.page-about .topic-list__item {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .02em;
  padding: 8px 14px;
  color: var(--c-cream);
  border: 1px solid var(--c-line-strong);
  border-radius: 999px;
  background: rgba(62, 107, 79, .14);
}

@media (min-width: 940px) {
  .page-about .columnists {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
    gap: clamp(36px, 5vw, 72px);
  }
}

/* ============ 合作生态 ============ */
.page-about .eco-split {
  display: grid;
  gap: clamp(28px, 4.5vw, 56px);
}

.page-about .eco-split__body .headline {
  margin: 10px 0 18px;
}

.page-about .eco-split__body .prose {
  color: var(--c-sage);
  line-height: 1.9;
}

.page-about .eco-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 1px;
  margin: clamp(24px, 3vw, 34px) 0 0;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--r);
  overflow: hidden;
}

.page-about .eco-stats .stat {
  background: var(--c-night);
  padding: clamp(16px, 2.2vw, 22px);
}

.page-about .eco-stats .stat__value {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(22px, 2.8vw, 32px);
  line-height: 1;
  font-weight: 700;
  letter-spacing: -.03em;
}

.page-about .eco-stats .stat__label {
  display: block;
  margin-top: 9px;
  font-size: 13px;
  line-height: 1.65;
  color: var(--c-sage);
}

.page-about .eco-note {
  margin: 22px 0 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--c-sage);
}

.page-about .eco-split__media .media {
  margin-top: 0;
}

@media (min-width: 960px) {
  .page-about .eco-split {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, .92fr);
    align-items: start;
    gap: clamp(36px, 5vw, 72px);
  }
}

/* ============ 纠错流程 ============ */
.page-about .fix-grid {
  display: grid;
  gap: 1px;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--r);
  overflow: hidden;
}

.page-about .fix-cell {
  background: var(--c-night);
  padding: clamp(20px, 2.6vw, 28px);
  border-left: 2px solid transparent;
  transition: border-color .3s var(--ease), background-color .3s var(--ease);
}

.page-about .fix-cell.is-visible {
  border-left-color: var(--c-lime);
}

.page-about .fix-cell__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--c-clay);
}

.page-about .fix-cell__title {
  margin: 12px 0 8px;
  font-size: 16px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--c-flood);
}

.page-about .fix-cell__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--c-sage);
}

@media (min-width: 760px) {
  .page-about .fix-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

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

.page-about .fix-cta {
  margin-top: clamp(24px, 3.4vw, 36px);
  padding: clamp(20px, 2.8vw, 30px);
  border: 1px solid var(--c-line-strong);
  border-radius: var(--r);
  background: linear-gradient(120deg, rgba(62, 107, 79, .22) 0%, rgba(14, 27, 42, .5) 100%);
}

.page-about .fix-cta__text {
  margin: 0 0 18px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--c-cream);
}

/* ============ 滚动显现 ============ */
.page-about [data-reveal][data-reveal-ready] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity .7s var(--ease), transform .7s var(--ease);
}

.page-about [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  .page-about [data-reveal][data-reveal-ready] {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .page-about .tl__item::before,
  .page-about .tl__year,
  .page-about .fix-cell {
    transition: none;
  }
}

/* ============ 窄屏兜底 ============ */
@media (max-width: 620px) {
  .page-about .tl {
    padding-left: 20px;
  }

  .page-about .hero-stats {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .divide-item {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .fix-cta .cluster {
    align-items: stretch;
  }

  .page-about .fix-cta .btn {
    width: 100%;
    text-align: center;
  }
}