.page-about {
  --about-rail: 176px;
  --about-gap: clamp(44px, 6vw, 92px);
  background: var(--jn-paper);
  color: var(--jn-ink);
  padding-bottom: clamp(56px, 8vw, 108px);
}

/* ---------- 外壳与左侧刻度尺 ---------- */
.page-about .about-shell {
  max-width: var(--jn-maxw);
  margin: 0 auto;
  padding: 0 var(--jn-gutter);
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
  min-width: 0;
}

.page-about .about-rail {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 12px 0;
  border-bottom: 1px solid var(--jn-hair);
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .about-rail__label {
  flex: none;
  margin: 0;
  font-family: var(--jn-font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--jn-gray);
}

.page-about .about-rail__list {
  display: flex;
  gap: 2px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-rail__link {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  min-height: 44px;
  padding: 0 12px;
  font-size: 13px;
  color: var(--jn-gray);
  text-decoration: none;
  white-space: nowrap;
  transition: color .2s var(--jn-ease), transform .2s var(--jn-ease);
}

.page-about .about-rail__link .jn-mono {
  font-size: 11px;
  letter-spacing: .1em;
}

.page-about .about-rail__link::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 2px;
  height: 14px;
  margin-top: -7px;
  background: transparent;
  transition: background .2s var(--jn-ease);
}

.page-about .about-rail__link[aria-current] {
  color: var(--jn-teal-500);
}

.page-about .about-rail__link[aria-current]::before {
  background: var(--jn-red);
}

.page-about .about-rail__link:hover {
  color: var(--jn-ink);
}

/* ---------- 主列 ---------- */
.page-about .about-body {
  display: flex;
  flex-direction: column;
  gap: var(--about-gap);
  min-width: 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  border-bottom: 1px solid var(--jn-hair);
  padding-bottom: clamp(28px, 4vw, 52px);
}

.page-about .about-hero__kicker {
  margin: 24px 0 0;
  font-family: var(--jn-font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--jn-red);
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-family: var(--jn-font-head);
  font-weight: 900;
  font-size: clamp(1.95rem, 6.2vw, 3.4rem);
  line-height: 1.12;
  letter-spacing: -.02em;
  max-width: 20ch;
}

.page-about .about-hero__lede {
  margin: 20px 0 0;
  max-width: 60ch;
  font-size: clamp(1rem, 1.5vw, 1.1rem);
  line-height: 1.82;
}

.page-about .about-hero__lede + .about-hero__lede {
  margin-top: 14px;
  font-size: .98rem;
  color: var(--jn-gray);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(26px, 4vw, 42px) 0 0;
  padding: 0;
  background: var(--jn-hair);
  border: 1px solid var(--jn-hair);
}

.page-about .about-hero__fact {
  background: var(--jn-paper);
  padding: 15px 16px;
  min-width: 0;
}

.page-about .about-hero__fact dt {
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--jn-gray);
}

.page-about .about-hero__fact dd {
  margin: 9px 0 0;
  font-family: var(--jn-font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.25rem, 3vw, 1.75rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.01em;
  color: var(--jn-neon);
}

/* ---------- 章节通用 ---------- */
.page-about .about-section {
  scroll-margin-top: calc(var(--jn-header-h-compact) + 24px);
  min-width: 0;
}

.page-about .about-section__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--jn-hair-strong);
  margin-bottom: clamp(22px, 3.4vw, 36px);
}

.page-about .about-section__num {
  flex: none;
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--jn-red);
}

.page-about .about-section__title {
  margin: 0;
  font-family: var(--jn-font-head);
  font-weight: 900;
  font-size: clamp(1.35rem, 3.4vw, 2.05rem);
  line-height: 1.25;
  letter-spacing: -.015em;
}

.page-about .about-section__lede {
  margin: 0 0 clamp(22px, 3vw, 34px);
  max-width: 62ch;
  line-height: 1.82;
  font-size: .98rem;
  color: var(--jn-gray);
}

/* ---------- 图 ---------- */
.page-about .jn-figure {
  margin: 0;
  position: relative;
  border: 1px solid var(--jn-hair);
  background: var(--jn-teal-wash);
  min-width: 0;
}

.page-about .jn-figure__img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .jn-figure__cap {
  display: block;
  padding: 10px 14px;
  border-top: 1px solid var(--jn-hair);
  background: var(--jn-paper);
  font-family: var(--jn-font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--jn-gray);
}

/* ---------- 01 品牌自述 ---------- */
.page-about .about-brand {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 46px);
}

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

.page-about .about-brand__text p {
  margin: 0 0 18px;
  max-width: 60ch;
  line-height: 1.82;
}

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

.page-about .about-quote {
  border-left: 3px solid var(--jn-red);
  padding: 3px 0 3px 18px;
  font-size: clamp(1.02rem, 1.7vw, 1.2rem);
  line-height: 1.72;
  font-weight: 500;
  color: var(--jn-teal-700);
  max-width: 52ch;
}

/* ---------- 02 团队 ---------- */
.page-about .about-team {
  border-top: 1px solid var(--jn-hair);
}

.page-about .about-team__item {
  border-bottom: 1px solid var(--jn-hair);
}

.page-about .about-team__item > summary {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 14px;
  min-height: 56px;
  padding: 16px 34px 16px 2px;
  cursor: pointer;
  list-style: none;
  touch-action: manipulation;
}

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

.page-about .about-team__item > summary::after {
  content: "+";
  position: absolute;
  right: 2px;
  top: 15px;
  font-family: var(--jn-font-mono);
  font-size: 17px;
  line-height: 1;
  color: var(--jn-teal-500);
  transition: color .2s var(--jn-ease);
}

.page-about .about-team__item[open] > summary::after {
  content: "–";
  color: var(--jn-red);
}

.page-about .about-team__no {
  flex: none;
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--jn-red);
}

.page-about .about-team__name {
  font-family: var(--jn-font-head);
  font-weight: 900;
  font-size: clamp(1.02rem, 1.8vw, 1.18rem);
  letter-spacing: -.01em;
}

.page-about .about-team__role {
  font-size: 13px;
  color: var(--jn-gray);
}

.page-about .about-team__body {
  padding: 0 2px 20px;
  max-width: 62ch;
}

.page-about .about-team__body p {
  margin: 0;
  line-height: 1.8;
  font-size: .96rem;
}

/* ---------- 03 工序 ---------- */
.page-about .about-craft {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 4vw, 48px);
}

.page-about .about-flow {
  margin: 0;
  padding: 0;
  list-style: none;
  min-width: 0;
}

.page-about .about-flow__step {
  position: relative;
  display: flex;
  gap: 16px;
  padding-bottom: 26px;
}

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

.page-about .about-flow__step::before {
  content: "";
  position: absolute;
  left: 23px;
  top: 32px;
  bottom: 4px;
  width: 1px;
  background: var(--jn-hair-strong);
}

.page-about .about-flow__step:last-child::before {
  display: none;
}

.page-about .about-flow__no {
  flex: none;
  width: 47px;
  height: 30px;
  display: grid;
  place-items: center;
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--jn-teal-500);
  background: var(--jn-paper);
  border: 1px solid var(--jn-hair-strong);
  position: relative;
  z-index: 1;
}

.page-about .about-flow__body {
  min-width: 0;
  padding-top: 2px;
}

.page-about .about-flow__title {
  margin: 0 0 6px;
  font-family: var(--jn-font-head);
  font-weight: 900;
  font-size: clamp(1rem, 1.7vw, 1.12rem);
}

.page-about .about-flow__text {
  margin: 0;
  max-width: 56ch;
  line-height: 1.78;
  font-size: .95rem;
  color: var(--jn-gray);
}

/* ---------- 04 时间轴 ---------- */
.page-about .about-era {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 4vw, 48px);
}

.page-about .about-timeline {
  margin: 0;
  padding: 0;
  list-style: none;
  min-width: 0;
}

.page-about .about-timeline__node {
  position: relative;
  padding: 0 0 30px 26px;
  border-left: 1px solid var(--jn-hair-strong);
}

.page-about .about-timeline__node::before {
  content: "";
  position: absolute;
  left: -4px;
  top: 6px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--jn-teal-500);
}

.page-about .about-timeline__node--start::before {
  background: var(--jn-red);
}

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

.page-about .about-timeline__year {
  display: inline-block;
  margin-bottom: 7px;
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--jn-teal-500);
}

.page-about .about-timeline__node--start .about-timeline__year {
  color: var(--jn-red);
}

.page-about .about-timeline__title {
  margin: 0 0 7px;
  font-family: var(--jn-font-head);
  font-weight: 900;
  font-size: clamp(1rem, 1.7vw, 1.14rem);
}

.page-about .about-timeline__text {
  margin: 0 0 7px;
  max-width: 56ch;
  line-height: 1.78;
  font-size: .95rem;
}

.page-about .about-timeline__note {
  margin: 0;
  max-width: 56ch;
  font-size: 13px;
  line-height: 1.7;
  color: var(--jn-gray);
  opacity: .68;
  transform: translateY(-2px);
  transition: opacity .24s var(--jn-ease), transform .24s var(--jn-ease);
}

.page-about .about-timeline__node:hover .about-timeline__note,
.page-about .about-timeline__node:focus-within .about-timeline__note {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- 05 合作 ---------- */
.page-about .about-partners {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3.6vw, 40px);
}

.page-about .about-partners__item {
  border-top: 1px solid var(--jn-hair-strong);
  padding-top: 18px;
  min-width: 0;
}

.page-about .about-partners__no {
  display: block;
  margin-bottom: 10px;
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--jn-red);
}

.page-about .about-partners__title {
  margin: 0 0 10px;
  font-family: var(--jn-font-head);
  font-weight: 900;
  font-size: clamp(1.05rem, 2vw, 1.24rem);
}

.page-about .about-partners__item p {
  margin: 0;
  max-width: 46ch;
  line-height: 1.78;
  font-size: .95rem;
  color: var(--jn-gray);
}

.page-about .about-partners__cta {
  margin: clamp(24px, 3.4vw, 36px) 0 0;
  font-size: .95rem;
  color: var(--jn-gray);
}

.page-about .about-partners__cta a,
.page-about .about-credit__col a {
  color: var(--jn-teal-500);
  text-decoration: none;
  border-bottom: 1px solid var(--jn-hair-strong);
  transition: color .2s var(--jn-ease), border-color .2s var(--jn-ease);
}

.page-about .about-partners__cta a:hover,
.page-about .about-credit__col a:hover {
  color: var(--jn-red);
  border-bottom-color: var(--jn-red);
}

/* ---------- 06 引用与反馈 ---------- */
.page-about .about-credit {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 44px);
}

.page-about .about-credit__col {
  border-left: 1px solid var(--jn-hair-strong);
  padding-left: clamp(18px, 2.6vw, 26px);
  min-width: 0;
}

.page-about .about-credit__title {
  margin: 0 0 12px;
  font-family: var(--jn-font-head);
  font-weight: 900;
  font-size: clamp(1.02rem, 1.8vw, 1.18rem);
}

.page-about .about-credit__col p {
  margin: 0 0 12px;
  max-width: 54ch;
  line-height: 1.8;
  font-size: .95rem;
}

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

.page-about .about-credit__mail {
  display: inline-block;
  padding: 2px 7px;
  font-family: var(--jn-font-mono);
  font-size: .88em;
  color: var(--jn-ink);
  background: var(--jn-red-100);
}

/* ---------- 尾部 ---------- */
.page-about .about-next {
  border-top: 1px solid var(--jn-hair-strong);
  padding-top: clamp(24px, 3.4vw, 38px);
  min-width: 0;
}

.page-about .about-next__label {
  margin: 0 0 14px;
  font-size: 11px;
  letter-spacing: .2em;
  color: var(--jn-gray);
}

.page-about .about-next__text {
  margin: 0 0 22px;
  max-width: 56ch;
  line-height: 1.8;
}

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

/* ---------- 断点：平板及以上 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 820px) {
  .page-about .about-partners {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    align-items: start;
  }

  .page-about .about-partners__item:nth-child(2) {
    margin-top: 34px;
  }

  .page-about .about-partners__item:nth-child(3) {
    margin-top: 68px;
  }
}

@media (min-width: 860px) {
  .page-about .about-brand {
    grid-template-columns: minmax(0, 1.06fr) minmax(0, .94fr);
    align-items: start;
    gap: clamp(32px, 5vw, 62px);
  }

  .page-about .about-brand__figure {
    margin-top: 58px;
  }

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

  .page-about .about-credit__col--offset {
    margin-top: 46px;
  }
}

@media (min-width: 900px) {
  .page-about .about-craft {
    grid-template-columns: minmax(0, 1fr) minmax(0, .82fr);
    align-items: start;
    gap: clamp(30px, 4vw, 54px);
  }

  .page-about .about-craft__figure {
    margin-top: 42px;
  }

  .page-about .about-era {
    grid-template-columns: minmax(0, 1.32fr) minmax(0, .68fr);
    align-items: start;
    gap: clamp(32px, 5vw, 64px);
  }

  .page-about .about-era__figure {
    margin-top: 18px;
  }
}

/* ---------- 断点：桌面，左侧刻度尺转为粘性竖列 ---------- */
@media (min-width: 1000px) {
  .page-about .about-shell {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(30px, 4vw, 68px);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--jn-header-h-compact) + 30px);
    flex-direction: column;
    align-items: stretch;
    gap: 18px;
    overflow: visible;
    padding: 2px 0 0;
    border-bottom: 0;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    gap: 0;
    position: relative;
    padding-left: 20px;
  }

  .page-about .about-rail__list::before {
    content: "";
    position: absolute;
    left: 0;
    top: 6px;
    bottom: 6px;
    width: 1px;
    background: var(--jn-hair-strong);
  }

  .page-about .about-rail__link {
    min-height: 0;
    padding: 9px 0 9px 4px;
    margin-left: -20px;
    padding-left: 20px;
  }

  .page-about .about-rail__link::before {
    left: 0;
    margin-top: -8px;
    height: 16px;
  }

  .page-about .about-rail__link[aria-current] {
    transform: translateX(4px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .about-timeline__note,
  .page-about .about-team__item > summary::after {
    transition: none;
  }

  .page-about .about-rail__link[aria-current] {
    transform: none;
  }
}