.page-about {
  --about-rail: 168px;
  --about-gap: clamp(20px, 3.4vw, 40px);
  position: relative;
  padding-top: clamp(16px, 3vw, 32px);
  background-color: var(--ink);
  background-image:
    linear-gradient(rgba(242, 247, 245, .022) 1px, transparent 1px),
    linear-gradient(90deg, rgba(242, 247, 245, .022) 1px, transparent 1px);
  background-size: 76px 76px, 76px 76px;
  color: var(--paper);
  font-family: var(--font-body);
  overflow-x: hidden;
}

.page-about .display {
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -.015em;
  line-height: 1.06;
  color: var(--paper);
}

/* ── 面包屑 ───────────────────────────── */
.page-about .about-crumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--paper-soft);
}

.page-about .about-crumb a {
  color: var(--paper-soft);
  text-decoration: none;
  transition: color .22s var(--ease);
}

.page-about .about-crumb a:hover {
  color: var(--cyan);
}

.page-about .about-crumb li + li::before {
  content: "/";
  margin-right: 6px;
  color: var(--line-strong);
}

/* ── 首屏 ─────────────────────────────── */
.page-about .about-hero {
  padding: clamp(20px, 3vw, 36px) 0 clamp(34px, 6vw, 76px);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(24px, 4vw, 46px);
  align-items: center;
}

.page-about .about-hero__copy {
  position: relative;
  padding-left: 18px;
}

.page-about .about-hero__copy::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 2px;
  background: linear-gradient(180deg, var(--cyan), var(--orange) 58%, transparent);
}

.page-about .about-hero__copy .exhibit-tag {
  display: inline-block;
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: .68rem;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-hero__title {
  margin: 0 0 18px;
  font-size: clamp(2.05rem, 7.6vw, 4.1rem);
}

.page-about .about-hero__lede {
  margin: 0 0 26px;
  max-width: 46ch;
  font-size: clamp(.97rem, 1.6vw, 1.08rem);
  line-height: 1.8;
  color: var(--paper-dim);
}

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

.page-about .about-hero__media {
  position: relative;
  display: flex;
  flex-direction: column;
  margin: 0;
  min-height: 250px;
  clip-path: var(--cut-lg);
  background: linear-gradient(160deg, var(--blue-a), var(--ink-deep));
  border: 1px solid var(--line-strong);
}

.page-about .about-hero__media img {
  display: block;
  width: 100%;
  height: 100%;
  min-height: 250px;
  object-fit: cover;
  filter: saturate(.82) contrast(1.06);
}

.page-about .about-hero__media .media__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  margin: 0;
  padding: 40px 18px 16px;
  background: linear-gradient(180deg, rgba(6, 43, 38, 0), rgba(6, 34, 31, .94));
  font-family: var(--font-mono);
  font-size: .7rem;
  line-height: 1.6;
  letter-spacing: .04em;
  color: var(--paper-dim);
}

/* ── 数据板 ───────────────────────────── */
.page-about .about-board {
  position: relative;
  background: rgba(11, 15, 16, .62);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .about-board::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: min(240px, 46%);
  height: 2px;
  background: linear-gradient(90deg, var(--orange), rgba(255, 107, 26, 0));
}

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

.page-about .about-board__cell {
  padding: 24px 18px;
  border-left: 1px solid var(--line);
}

.page-about .about-board__cell:nth-child(odd) {
  border-left: 0;
  padding-left: 0;
}

.page-about .about-board__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.65rem, 4.6vw, 2.5rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--lime);
}

.page-about .about-board__num em {
  font-style: normal;
  font-size: .5em;
  margin-left: 2px;
  color: var(--orange);
}

.page-about .about-board__label {
  display: block;
  margin-top: 10px;
  font-size: .8rem;
  line-height: 1.55;
  color: var(--paper-soft);
}

/* ── 主体两栏 ─────────────────────────── */
.page-about .about-body {
  display: grid;
  gap: var(--about-gap);
  padding: clamp(44px, 6vw, 76px) 0 clamp(48px, 8vw, 96px);
}

.page-about .about-rail {
  display: none;
}

.page-about .about-rail__mark {
  margin: 0 0 20px;
  font-family: var(--font-mono);
  font-size: .66rem;
  letter-spacing: .24em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 15px;
}

.page-about .about-rail__list a {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: .88rem;
  color: var(--paper-dim);
  text-decoration: none;
  transition: color .22s var(--ease);
}

.page-about .about-rail__list a::before {
  content: "";
  width: 16px;
  height: 1px;
  flex: none;
  background: var(--line-strong);
  transition: width .26s var(--ease), background .26s var(--ease);
}

.page-about .about-rail__list a:hover {
  color: var(--paper);
}

.page-about .about-rail__list a:hover::before {
  width: 28px;
  background: var(--orange);
}

.page-about .about-rail__coord {
  margin: 24px 0 0;
  font-family: var(--font-mono);
  font-size: .66rem;
  letter-spacing: .1em;
  color: var(--paper-soft);
}

/* ── 章节通用 ─────────────────────────── */
.page-about .about-section {
  scroll-margin-top: calc(var(--header-h) + 24px);
}

.page-about .about-section + .about-section {
  margin-top: clamp(44px, 7vw, 86px);
  padding-top: clamp(34px, 5vw, 58px);
  border-top: 1px solid var(--line);
}

.page-about .about-section .section__index {
  margin: 0;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--orange);
}

.page-about .about-section__title {
  margin: 12px 0 18px;
  max-width: 22ch;
  font-size: clamp(1.65rem, 4.6vw, 2.85rem);
}

.page-about .about-section__lede {
  margin: 0 0 28px;
  max-width: 62ch;
  font-size: 1rem;
  line-height: 1.82;
  color: var(--paper-dim);
}

/* ── 01 品牌故事 ──────────────────────── */
.page-about .about-story {
  display: grid;
  gap: 24px;
}

.page-about .about-story__text p {
  margin: 0 0 16px;
  font-size: .98rem;
  line-height: 1.88;
  color: var(--paper-dim);
}

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

.page-about .about-story__card {
  padding: 26px 24px;
  background: linear-gradient(152deg, rgba(110, 31, 58, .95), rgba(46, 26, 94, .6));
  border: 1px solid var(--line-strong);
}

.page-about .about-story__card-label {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: .66rem;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--lime);
}

.page-about .about-story__card-title {
  margin: 0 0 18px;
  font-family: var(--font-display);
  font-size: 1.34rem;
  line-height: 1.32;
  font-weight: 800;
  color: var(--paper);
}

.page-about .about-story__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 11px;
}

.page-about .about-story__list li {
  position: relative;
  padding-left: 20px;
  font-size: .9rem;
  line-height: 1.6;
  color: var(--paper-dim);
}

.page-about .about-story__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .58em;
  width: 8px;
  height: 8px;
  background: var(--cyan);
  clip-path: polygon(0 0, 100% 0, 0 100%);
}

/* ── 02 覆盖网络 ──────────────────────── */
.page-about .about-network__media {
  margin: 0 0 22px;
  clip-path: var(--cut-lg);
  background: linear-gradient(135deg, var(--blue-a), var(--indigo));
  border: 1px solid var(--line);
}

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

.page-about .about-network__media .media__caption {
  margin: 0;
  padding: 13px 18px 16px;
  font-family: var(--font-mono);
  font-size: .7rem;
  line-height: 1.6;
  color: var(--paper-soft);
}

.page-about .about-network__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 26px;
  padding: 0;
  list-style: none;
}

.page-about .about-network__tags .tag {
  padding: 6px 13px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .02em;
  color: var(--paper-dim);
  transition: border-color .22s var(--ease), color .22s var(--ease);
}

.page-about .about-network__tags .tag:hover {
  border-color: var(--cyan);
  color: var(--paper);
}

.page-about .about-network__notes {
  display: grid;
  gap: 16px;
}

.page-about .about-network__note {
  padding: 22px 22px;
  background: rgba(11, 15, 16, .72);
  border-left: 2px solid var(--cyan);
}

.page-about .about-network__note:last-child {
  border-left-color: var(--orange);
}

.page-about .about-network__note-title {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 1.08rem;
  font-weight: 800;
  color: var(--paper);
}

.page-about .about-network__note-text {
  margin: 0;
  font-size: .92rem;
  line-height: 1.78;
  color: var(--paper-dim);
}

/* ── 03 版本演进 ──────────────────────── */
.page-about .about-eras {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-eras::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 14px;
  bottom: 16px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan), var(--orange) 55%, var(--indigo));
}

.page-about .about-era {
  position: relative;
  padding: 0 0 22px 36px;
}

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

.page-about .about-era::before {
  content: "";
  position: absolute;
  left: 3px;
  top: 9px;
  width: 11px;
  height: 11px;
  background: var(--ink);
  border: 2px solid var(--cyan);
  transform: rotate(45deg);
}

.page-about .about-era summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 14px;
  padding: 4px 0;
  list-style: none;
  cursor: pointer;
}

.page-about .about-era summary::-webkit-details-marker {
  display: none;
}

.page-about .about-era summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--paper-soft);
  transition: color .22s var(--ease);
}

.page-about .about-era details[open] summary::after {
  content: "–";
  color: var(--orange);
}

.page-about .about-era summary:hover .about-era__name {
  color: var(--cyan);
}

.page-about .about-era__year {
  font-family: var(--font-mono);
  font-size: .92rem;
  font-weight: 700;
  letter-spacing: .04em;
  color: var(--lime);
}

.page-about .about-era__name {
  font-family: var(--font-display);
  font-size: 1.12rem;
  font-weight: 800;
  color: var(--paper);
  transition: color .22s var(--ease);
}

.page-about .about-era__body {
  padding: 12px 0 0;
}

.page-about .about-era__body p {
  margin: 0;
  max-width: 62ch;
  font-size: .94rem;
  line-height: 1.82;
  color: var(--paper-dim);
}

/* ── 04 合作生态 ──────────────────────── */
.page-about .about-partners {
  display: grid;
  gap: 24px;
  margin: 0 0 30px;
}

.page-about .about-partners__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 18px;
}

.page-about .about-partners__item {
  position: relative;
  padding: 20px 22px 20px 26px;
  background: rgba(6, 34, 31, .62);
  clip-path: var(--cut);
  border-left: 2px solid var(--lime);
}

.page-about .about-partners__item:nth-child(2) {
  border-left-color: var(--cyan);
}

.page-about .about-partners__item:nth-child(3) {
  border-left-color: var(--orange);
}

.page-about .about-partners__num {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 1.7rem;
  font-weight: 700;
  line-height: 1;
  color: var(--lime);
}

.page-about .about-partners__name {
  margin: 8px 0 8px;
  font-family: var(--font-display);
  font-size: 1.08rem;
  font-weight: 800;
  color: var(--paper);
}

.page-about .about-partners__desc {
  margin: 0;
  font-size: .9rem;
  line-height: 1.75;
  color: var(--paper-dim);
}

.page-about .about-partners__media {
  margin: 0;
  clip-path: var(--cut-lg);
  background: linear-gradient(140deg, var(--indigo), var(--ink-deep));
  border: 1px solid var(--line);
}

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

.page-about .about-partners__media .media__caption {
  margin: 0;
  padding: 13px 18px 16px;
  font-family: var(--font-mono);
  font-size: .7rem;
  line-height: 1.6;
  color: var(--paper-soft);
}

.page-about .about-team {
  padding-top: 26px;
  border-top: 1px dashed var(--line-strong);
}

.page-about .about-team__title {
  margin: 0 0 20px;
  font-family: var(--font-display);
  font-size: 1.24rem;
  font-weight: 800;
  color: var(--paper);
}

.page-about .about-team__grid {
  display: grid;
  gap: 16px;
}

.page-about .about-team__item {
  padding-left: 14px;
  border-left: 1px solid var(--line-strong);
}

.page-about .about-team__key {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: .76rem;
  letter-spacing: .12em;
  color: var(--cyan);
}

.page-about .about-team__val {
  margin: 0;
  font-size: .9rem;
  line-height: 1.75;
  color: var(--paper-dim);
}

/* ── 05 为什么选我们 ──────────────────── */
.page-about .about-why {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .about-why__item {
  position: relative;
  padding: 24px 22px;
  clip-path: var(--cut);
  background: linear-gradient(160deg, rgba(11, 15, 16, .92), rgba(6, 43, 38, .78));
  border: 1px solid var(--line);
  transition: transform .3s var(--ease), border-color .3s var(--ease);
}

.page-about .about-why__item:hover {
  transform: translateY(-4px);
  border-color: var(--line-strong);
}

.page-about .about-why__no {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 700;
  line-height: 1;
  color: var(--orange);
}

.page-about .about-why__title {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 1.16rem;
  font-weight: 800;
  color: var(--paper);
}

.page-about .about-why__text {
  margin: 0;
  font-size: .92rem;
  line-height: 1.8;
  color: var(--paper-dim);
}

/* ── 尾部邀约 ─────────────────────────── */
.page-about .about-cta {
  padding: 0 0 clamp(52px, 8vw, 96px);
}

.page-about .about-cta__inner {
  padding: clamp(28px, 5vw, 54px);
  background: linear-gradient(140deg, rgba(46, 26, 94, .95), rgba(6, 43, 38, .92) 72%);
  border: 1px solid var(--line-strong);
}

.page-about .about-cta__title {
  margin: 0 0 16px;
  font-size: clamp(1.55rem, 4vw, 2.45rem);
}

.page-about .about-cta__text {
  margin: 0 0 26px;
  max-width: 56ch;
  font-size: .98rem;
  line-height: 1.82;
  color: var(--paper-dim);
}

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

/* ── 桌面断点 ─────────────────────────── */
@media (min-width: 640px) {
  .page-about .about-network__notes {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-team__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 22px;
  }

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

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

  .page-about .about-board__cell:nth-child(odd) {
    border-left: 1px solid var(--line);
    padding-left: 18px;
  }

  .page-about .about-board__cell:first-child {
    border-left: 0;
    padding-left: 0;
  }
}

@media (min-width: 860px) {
  .page-about .about-story {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, .9fr);
    gap: 32px;
    align-items: start;
  }

  .page-about .about-partners {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
    gap: 30px;
    align-items: start;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.02fr) minmax(0, .98fr);
    align-items: stretch;
  }
}

@media (min-width: 1000px) {
  .page-about .about-body {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(30px, 4.5vw, 68px);
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: calc(var(--header-h) + 28px);
    align-self: start;
    padding-right: 22px;
    border-right: 1px solid var(--line);
  }
}

@media (min-width: 1200px) {
  .page-about {
    --about-rail: 188px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-why__item,
  .page-about .about-rail__list a::before {
    transition: none;
  }

  .page-about .about-why__item:hover {
    transform: none;
  }
}