.page-about {
  --about-index-w: 204px;
  --about-rule: rgba(243, 233, 215, 0.14);
  --about-soft: rgba(243, 233, 215, 0.08);
  --about-body: rgba(251, 248, 242, 0.76);
  --about-body-dim: rgba(251, 248, 242, 0.68);
  background-color: var(--ink);
  background-image: repeating-linear-gradient(
    115deg,
    rgba(18, 54, 60, 0.5) 0 1px,
    transparent 1px 96px
  );
  color: var(--white);
}

/* 面包屑 */
.page-about .breadcrumb {
  padding-top: 26px;
}
.page-about .breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 0.78rem;
  letter-spacing: 0.06em;
}
.page-about .breadcrumb-list li::after {
  content: "/";
  margin-left: 8px;
  color: var(--mute);
}
.page-about .breadcrumb-list li:last-child::after {
  content: none;
}
.page-about .breadcrumb-link {
  color: var(--mute);
  text-decoration: none;
  transition: color 0.22s var(--ease);
}
.page-about .breadcrumb-link:hover,
.page-about .breadcrumb-link:focus-visible {
  color: var(--cyan);
}
.page-about .breadcrumb-current {
  color: var(--paper);
}

/* 首屏 */
.page-about .about-hero {
  padding: 58px 0 0;
}
.page-about .about-hero .eyebrow {
  margin: 0;
  color: var(--gold);
  font-size: 0.7rem;
  letter-spacing: 0.2em;
}
.page-about .about-hero__title {
  margin: 22px 0 0;
  font-size: clamp(2.35rem, 11.5vw, 8.6rem);
  font-weight: 200;
  line-height: 0.94;
  letter-spacing: -0.03em;
  color: var(--paper);
}
.page-about .about-hero__lede {
  margin: 34px 0 0;
  max-width: 660px;
  font-size: 1rem;
  line-height: 1.95;
  color: var(--about-body);
}

/* 索引 + 长卷 */
.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 46px;
  padding-top: 86px;
}
.page-about .about-index {
  min-width: 0;
}
.page-about .about-index .index-label {
  margin: 0;
  color: var(--gold);
  font-size: 0.68rem;
  letter-spacing: 0.22em;
}
.page-about .about-index__list {
  display: flex;
  gap: 8px;
  margin: 14px 0 0;
  padding: 0 0 8px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
}
.page-about .about-index__list::-webkit-scrollbar {
  display: none;
}
.page-about .about-index__link {
  display: block;
  white-space: nowrap;
  padding: 7px 14px;
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  color: var(--mute);
  text-decoration: none;
  border: 1px solid var(--about-soft);
  clip-path: polygon(0 0, calc(100% - 10px) 0, 100% 10px, 100% 100%, 0 100%);
  transition: color 0.22s var(--ease), border-color 0.22s var(--ease);
}
.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--cyan);
  border-color: rgba(59, 224, 196, 0.55);
}
.page-about .about-flow {
  min-width: 0;
}

/* 章节通用 */
.page-about .about-sec {
  padding-bottom: 84px;
  scroll-margin-top: calc(var(--header-h) + 24px);
}
.page-about .about-sec + .about-sec {
  padding-top: 72px;
  border-top: 1px solid var(--about-soft);
}
.page-about .section-head {
  margin: 0 0 32px;
}
.page-about .section-head .eyebrow {
  margin: 0;
  color: var(--gold);
  font-size: 0.68rem;
  letter-spacing: 0.2em;
}
.page-about .section-title {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(1.65rem, 5.4vw, 3rem);
  line-height: 1.14;
  letter-spacing: -0.015em;
  color: var(--paper);
}
.page-about .section-lede {
  margin: 18px 0 0;
  max-width: 640px;
  font-size: 0.97rem;
  line-height: 1.9;
  color: var(--about-body);
}

/* 正文 */
.page-about .about-prose p {
  margin: 0 0 20px;
  max-width: 680px;
  font-size: 0.99rem;
  line-height: 1.95;
  color: var(--about-body);
}
.page-about .about-prose p:first-child {
  padding-left: 18px;
  border-left: 2px solid var(--red);
}
.page-about .about-prose p:last-child {
  margin-bottom: 0;
}

/* 规模数据 */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 22px 18px;
  background-color: var(--panel);
  background-image: linear-gradient(150deg, rgba(18, 54, 60, 0.7), transparent 68%);
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 0 100%);
  transition: box-shadow 0.26s var(--ease);
}
.page-about .about-stat:hover {
  box-shadow: inset 0 0 0 1px rgba(59, 224, 196, 0.6);
}
.page-about .about-stat .index-label {
  color: var(--mute);
  font-size: 0.64rem;
  letter-spacing: 0.16em;
}
.page-about .about-stat__value {
  font-family: var(--font-mono);
  font-size: clamp(1.7rem, 7vw, 2.5rem);
  font-weight: 500;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--cyan);
}
.page-about .about-stat:nth-child(3n + 2) .about-stat__value {
  color: var(--gold);
}
.page-about .about-stat:nth-child(3n) .about-stat__value {
  color: var(--paper);
}
.page-about .about-stat__text {
  font-size: 0.82rem;
  line-height: 1.7;
  color: var(--mute);
}
.page-about .about-scale__note {
  margin-top: 30px;
  padding-left: 18px;
  border-left: 2px solid var(--red);
}
.page-about .about-scale__note p {
  margin: 0;
  max-width: 660px;
  font-size: 0.93rem;
  line-height: 1.9;
  color: var(--about-body-dim);
}

/* 配图 */
.page-about .about-figure {
  position: relative;
  margin: 0 0 34px;
  overflow: hidden;
  background-color: var(--panel);
  background-image: repeating-linear-gradient(
    115deg,
    rgba(18, 54, 60, 0.85) 0 1px,
    transparent 1px 54px
  );
  clip-path: polygon(0 0, calc(100% - 26px) 0, 100% 26px, 100% 100%, 0 100%);
}
.page-about .about-figure img {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
}
.page-about .about-figure--team {
  aspect-ratio: 14 / 9;
}
.page-about .about-figure--flow {
  aspect-ratio: 4 / 3;
}
.page-about .about-figure--line {
  aspect-ratio: 16 / 7;
  margin-bottom: 0;
}
.page-about .about-figure__cap {
  position: absolute;
  left: 16px;
  bottom: 14px;
  max-width: calc(100% - 32px);
  margin: 0;
  padding: 6px 12px;
  font-size: 0.74rem;
  letter-spacing: 0.03em;
  color: var(--paper);
  background-color: rgba(10, 18, 32, 0.78);
}

/* 团队 */
.page-about .about-teams {
  margin: 0;
  padding: 0;
  list-style: none;
}
.page-about .about-team {
  padding: 22px 0 18px;
  border-top: 1px solid var(--about-soft);
}
.page-about .about-team:last-child {
  border-bottom: 1px solid var(--about-soft);
}
.page-about .about-team__row {
  display: flex;
  align-items: baseline;
  gap: 14px;
}
.page-about .about-team__row .index-label {
  margin: 0;
  color: var(--red);
  font-size: 0.64rem;
  letter-spacing: 0.16em;
  filter: brightness(1.9);
}
.page-about .about-team__name {
  margin: 0;
  font-size: 1.06rem;
  font-weight: 500;
  color: var(--paper);
}
.page-about .about-team__count {
  margin: 0 0 0 auto;
  font-family: var(--font-mono);
  font-size: 1.28rem;
  font-weight: 500;
  color: var(--gold);
}
.page-about .about-team__count::after {
  content: " 人";
  font-size: 0.7rem;
  color: var(--mute);
}
.page-about .about-team__desc {
  margin: 10px 0 16px;
  max-width: 640px;
  font-size: 0.9rem;
  line-height: 1.85;
  color: var(--about-body-dim);
}
.page-about .about-team__track {
  display: block;
  width: 100%;
  max-width: 460px;
  height: 4px;
  background-color: rgba(243, 233, 215, 0.09);
}
.page-about .about-team__bar {
  display: block;
  height: 100%;
  width: var(--w, 20%);
  background-color: var(--cyan);
  transition: width 0.5s var(--ease);
}
.page-about .about-team:nth-child(2) .about-team__bar {
  background-color: var(--gold);
}

/* 归档流程 */
.page-about .about-steps {
  display: grid;
  gap: 2px;
  margin: 0;
}
.page-about .about-step {
  border-left: 2px solid var(--about-soft);
  background-image: linear-gradient(
    95deg,
    rgba(18, 32, 54, 0.92),
    rgba(18, 32, 54, 0.28)
  );
  transition: border-color 0.24s var(--ease);
}
.page-about .about-step[open] {
  border-left-color: var(--cyan);
}
.page-about .about-step .disclosure__summary {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 17px 18px;
  cursor: pointer;
  list-style: none;
}
.page-about .about-step .disclosure__summary::-webkit-details-marker {
  display: none;
}
.page-about .about-step .disclosure__summary::after {
  content: "+";
  margin-left: auto;
  font-size: 1.15rem;
  line-height: 1;
  color: var(--mute);
}
.page-about .about-step[open] .disclosure__summary::after {
  content: "−";
  color: var(--cyan);
}
.page-about .about-step .disclosure__index {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--gold);
}
.page-about .about-step__name {
  font-size: 0.99rem;
  font-weight: 500;
  color: var(--paper);
}
.page-about .about-step .disclosure__body {
  padding: 0 18px 20px 56px;
  border-top: 1px solid var(--about-soft);
}
.page-about .about-step .disclosure__body p {
  margin: 16px 0 0;
  max-width: 640px;
  font-size: 0.92rem;
  line-height: 1.9;
  color: var(--about-body-dim);
}

/* 时间轴 */
.page-about .about-timeline {
  display: flex;
  gap: 0;
  margin: 0 0 34px;
  padding: 34px 0 10px;
  overflow-x: auto;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
}
.page-about .about-timeline::-webkit-scrollbar {
  height: 3px;
}
.page-about .about-timeline::-webkit-scrollbar-thumb {
  background-color: rgba(59, 224, 196, 0.5);
}
.page-about .about-node {
  flex: 0 0 236px;
  position: relative;
  padding: 26px 22px 18px 0;
  border-top: 1px solid var(--about-rule);
  scroll-snap-align: start;
  transition: border-color 0.24s var(--ease);
}
.page-about .about-node::before {
  content: "";
  position: absolute;
  top: -5px;
  left: 0;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background-color: var(--cyan);
  box-shadow: 0 0 0 4px rgba(59, 224, 196, 0.14);
}
.page-about .about-node:last-child {
  padding-right: 4px;
}
.page-about .about-node:hover {
  border-top-color: var(--cyan);
}
.page-about .about-node__year {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 1.34rem;
  font-weight: 500;
  color: var(--gold);
}
.page-about .about-node__title {
  margin: 0 0 8px;
  font-size: 0.96rem;
  font-weight: 500;
  color: var(--paper);
}
.page-about .about-node__desc {
  margin: 0;
  font-size: 0.82rem;
  line-height: 1.78;
  color: var(--mute);
}

/* 长期做法 */
.page-about .about-holds {
  margin: 0;
  padding: 0;
  list-style: none;
}
.page-about .about-hold {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  gap: 4px 16px;
  padding: 24px 0;
  border-top: 1px solid var(--about-soft);
}
.page-about .about-hold:last-child {
  border-bottom: 1px solid var(--about-soft);
}
.page-about .about-hold__num {
  grid-row: 1 / span 2;
  padding: 4px 0 0 10px;
  border-left: 3px solid var(--red);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--mute);
}
.page-about .about-hold__name {
  margin: 0;
  font-size: 1.04rem;
  font-weight: 500;
  color: var(--paper);
}
.page-about .about-hold__text {
  margin: 0;
  max-width: 640px;
  font-size: 0.9rem;
  line-height: 1.88;
  color: var(--about-body-dim);
}

/* 下一步入口 */
.page-about .about-next {
  margin-top: 30px;
  padding: 66px 0 92px;
  background-image: linear-gradient(
    102deg,
    rgba(124, 31, 44, 0.28),
    rgba(18, 32, 54, 0.7) 58%,
    transparent
  );
}
.page-about .about-next__title {
  margin: 0;
  max-width: 720px;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(1.5rem, 5vw, 2.5rem);
  line-height: 1.2;
  letter-spacing: -0.015em;
  color: var(--paper);
}
.page-about .about-next__list {
  margin: 34px 0 0;
  padding: 0;
  list-style: none;
}
.page-about .about-next__item {
  border-top: 1px solid var(--about-soft);
}
.page-about .about-next__item:last-child {
  border-bottom: 1px solid var(--about-soft);
}
.page-about .about-next__link {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  grid-template-areas:
    "name arrow"
    "desc arrow";
  align-items: center;
  gap: 6px 18px;
  padding: 22px 0;
  text-decoration: none;
  transition: padding-left 0.26s var(--ease);
}
.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  padding-left: 14px;
}
.page-about .about-next__name {
  grid-area: name;
  font-size: 1.04rem;
  font-weight: 500;
  color: var(--paper);
}
.page-about .about-next__desc {
  grid-area: desc;
  font-size: 0.86rem;
  line-height: 1.7;
  color: var(--mute);
}
.page-about .about-next__arrow {
  grid-area: arrow;
  font-size: 1.15rem;
  color: var(--cyan);
}

/* 平板及以上 */
@media (min-width: 700px) {
  .page-about .about-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
  }
  .page-about .about-stat {
    padding: 26px 22px;
  }
  .page-about .about-prose p {
    font-size: 1.02rem;
  }
}

/* 桌面端：左侧固定索引 */
@media (min-width: 1000px) {
  .page-about .about-shell {
    grid-template-columns: var(--about-index-w) minmax(0, 1fr);
    column-gap: 72px;
    padding-top: 128px;
  }
  .page-about .about-index {
    position: sticky;
    top: calc(var(--header-h) + 32px);
    align-self: start;
  }
  .page-about .about-index__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding: 0;
  }
  .page-about .about-index__link {
    white-space: normal;
    padding: 9px 0 9px 16px;
    border: 0;
    border-left: 2px solid var(--about-soft);
    clip-path: none;
    font-size: 0.82rem;
  }
  .page-about .about-index__link:hover,
  .page-about .about-index__link:focus-visible {
    border-left-color: var(--red);
    color: var(--paper);
  }
  .page-about .about-hero {
    padding-top: 78px;
  }
  .page-about .about-hero__lede {
    font-size: 1.06rem;
    margin-top: 42px;
  }
  .page-about .about-sec {
    padding-bottom: 104px;
  }
  .page-about .about-sec + .about-sec {
    padding-top: 88px;
  }
  .page-about .about-node {
    flex-basis: 268px;
    padding-right: 30px;
  }
  .page-about .about-hold {
    grid-template-columns: 64px minmax(0, 1fr);
    padding: 28px 0;
  }
  .page-about .about-next {
    padding: 84px 0 118px;
  }
  .page-about .about-next__link {
    grid-template-columns: 260px minmax(0, 1fr) auto;
    grid-template-areas: "name desc arrow";
    padding: 24px 0;
  }
}

.page-about {
  --w: 1rem;
}