.page-about {
  background: var(--paper);
  color: var(--ink);
  --about-num-size: clamp(52px, 8.4vw, 92px);
  --about-rail-w: 236px;
  --about-sticky-top: 116px;
}

/* ---------- 首屏 ---------- */
.page-about .about-masthead {
  position: relative;
  overflow: hidden;
  background: var(--ink);
  color: var(--paper);
  padding: clamp(24px, 4vw, 44px) 0 clamp(40px, 7vw, 84px);
  border-bottom: 1px solid var(--gold-line-soft);
}
.page-about .about-masthead::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, var(--paper-08) 1px, transparent 1px),
    linear-gradient(to bottom, var(--paper-08) 1px, transparent 1px);
  background-size: 64px 64px;
  opacity: 0.5;
  pointer-events: none;
}
.page-about .about-masthead::after {
  content: "";
  position: absolute;
  right: -12%;
  top: -26%;
  width: 58%;
  height: 150%;
  background: linear-gradient(158deg, rgba(201, 162, 39, 0.16), rgba(201, 162, 39, 0) 62%);
  transform: rotate(-9deg);
  pointer-events: none;
}
.page-about .about-masthead .wrap {
  position: relative;
  z-index: 1;
}
.page-about .about-masthead .breadcrumb__link,
.page-about .about-masthead .breadcrumb__sep {
  color: var(--paper-52);
}
.page-about .about-masthead .breadcrumb__link:hover,
.page-about .about-masthead .breadcrumb__link:focus-visible {
  color: var(--gold);
}
.page-about .about-masthead .breadcrumb__current {
  color: var(--paper-warm);
}
.page-about .about-masthead .eyebrow {
  display: block;
  margin-top: clamp(28px, 4vw, 44px);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--gold);
}
.page-about .about-masthead__title {
  font-family: var(--serif);
  font-weight: 300;
  font-size: clamp(30px, 5.2vw, 62px);
  line-height: 1.2;
  letter-spacing: 0.004em;
  color: var(--paper-warm);
  margin: 18px 0 20px;
  max-width: 17ch;
}
.page-about .about-masthead__lede {
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.85;
  color: var(--paper-72);
  max-width: 62ch;
  margin: 0;
}
.page-about .about-masthead__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 16px;
  margin-top: clamp(24px, 3.4vw, 36px);
  padding-top: 18px;
  border-top: 1px solid var(--paper-16);
}
.page-about .about-masthead__ver {
  font-size: 12px;
  color: var(--paper-52);
  letter-spacing: 0.04em;
}

/* ---------- 主体网格 ---------- */
.page-about .about-body {
  padding: clamp(36px, 5.5vw, 76px) 0 clamp(56px, 8vw, 108px);
}
.page-about .about-body__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 4vw, 48px);
}
.page-about .about-body__main {
  counter-reset: chapter;
  min-width: 0;
}

/* ---------- 侧栏目录 ---------- */
.page-about .about-body__rail {
  order: -1;
  min-width: 0;
}
.page-about .about-toc {
  border: 1px solid var(--gold-line);
  background: var(--paper-warm);
  padding: 18px 16px 16px;
}
.page-about .about-toc__title {
  margin: 0 0 12px;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--fog);
}
.page-about .about-toc__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
}
.page-about .about-toc__link {
  display: grid;
  grid-template-columns: 22px minmax(0, 1fr);
  gap: 8px;
  align-items: baseline;
  padding: 7px 8px;
  font-size: 13px;
  line-height: 1.55;
  color: var(--ink-60);
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: color 0.22s var(--ease), border-color 0.22s var(--ease), background-color 0.22s var(--ease);
}
.page-about .about-toc__num {
  font-size: 10px;
  color: var(--gold-deep);
  letter-spacing: 0.08em;
}
.page-about .about-toc__link:hover,
.page-about .about-toc__link:focus-visible {
  color: var(--ink);
  border-left-color: var(--gold);
  background: rgba(201, 162, 39, 0.08);
}
.page-about .about-toc__link[aria-current="true"] {
  color: var(--gold-deep);
  border-left-color: var(--gold-deep);
  background: rgba(201, 162, 39, 0.1);
}
.page-about .about-toc__foot {
  margin-top: 14px;
  padding-top: 14px;
  border-top: 1px solid var(--ink-14);
  display: grid;
  gap: 8px;
}
.page-about .about-toc__note {
  margin: 0;
  font-size: 11px;
  line-height: 1.6;
  color: var(--fog);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-chapter {
  counter-increment: chapter;
  scroll-margin-top: calc(var(--about-sticky-top) + 12px);
}
.page-about .about-chapter + .about-chapter {
  margin-top: clamp(44px, 6.5vw, 84px);
  padding-top: clamp(36px, 5vw, 60px);
  border-top: 1px solid var(--ink-14);
}
.page-about .about-chapter__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: end;
  column-gap: clamp(12px, 2.4vw, 22px);
  padding-bottom: 12px;
  border-bottom: 1px solid var(--gold-line);
  margin-bottom: clamp(20px, 3vw, 32px);
}
.page-about .about-chapter__num {
  font-family: var(--serif);
  font-weight: 200;
  font-size: var(--about-num-size);
  line-height: 0.76;
  color: var(--gold);
  opacity: 0.42;
  letter-spacing: -0.03em;
  user-select: none;
}
.page-about .about-chapter__num::before {
  content: counter(chapter, decimal-leading-zero);
}
.page-about .about-chapter__title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(21px, 2.6vw, 31px);
  line-height: 1.32;
  margin: 0;
  color: var(--ink);
}
.page-about .about-chapter__lede {
  font-size: clamp(15px, 1.5vw, 16.5px);
  line-height: 1.85;
  color: var(--ink-60);
  margin: 0 0 clamp(24px, 3.4vw, 36px);
  max-width: 68ch;
}

/* ---------- 两列分栏 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 3.4vw, 40px);
}
.page-about .about-split--tight {
  gap: clamp(20px, 2.8vw, 32px);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
}
.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(to bottom, var(--gold-line), var(--gold-line-soft) 85%, transparent);
}
.page-about .about-timeline__item {
  position: relative;
  padding: 0 0 26px 32px;
}
.page-about .about-timeline__item:last-child {
  padding-bottom: 0;
}
.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  border: 1px solid var(--gold);
  background: var(--paper);
  transition: background-color 0.24s var(--ease), box-shadow 0.24s var(--ease), transform 0.24s var(--ease);
}
.page-about .about-timeline__item:hover::before {
  background: var(--gold);
  box-shadow: 0 0 0 4px rgba(201, 162, 39, 0.16);
  transform: scale(1.08);
}
.page-about .about-timeline__date {
  display: block;
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--gold-deep);
  text-transform: uppercase;
  margin-bottom: 6px;
}
.page-about .about-timeline__title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(16px, 1.7vw, 18px);
  line-height: 1.5;
  margin: 0 0 6px;
  color: var(--ink);
}
.page-about .about-timeline__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--ink-60);
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 0;
  min-width: 0;
}
.page-about .about-figure .media {
  display: block;
  width: 100%;
  border: 1px solid var(--gold-line-soft);
  background: var(--charcoal);
  overflow: hidden;
}
.page-about .about-figure img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.page-about .about-figure .figure-caption {
  margin: 10px 0 0;
  font-size: 12px;
  line-height: 1.65;
  color: var(--fog);
}
.page-about .about-figure--wide {
  margin: clamp(26px, 3.4vw, 36px) 0 0;
}

/* ---------- 四类内容 ---------- */
.page-about .about-kinds {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
  border-top: 1px solid var(--ink-14);
}
.page-about .about-kinds__item {
  padding: 20px 0 22px;
  border-bottom: 1px solid var(--ink-14);
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 8px;
}
.page-about .about-kinds__tag {
  justify-self: start;
}
.page-about .about-kinds__title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(16px, 1.8vw, 19px);
  line-height: 1.5;
  margin: 0;
  color: var(--ink);
}
.page-about .about-kinds__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.82;
  color: var(--ink-60);
  max-width: 66ch;
}

/* ---------- 更新记录 ---------- */
.page-about .about-ledger .ledger__week {
  border-bottom: 1px solid var(--ink-14);
}
.page-about .about-ledger .ledger__week:first-child {
  border-top: 1px solid var(--ink-14);
}
.page-about .about-ledger summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 14px;
  padding: 15px 30px 15px 12px;
  position: relative;
  border-left: 2px solid transparent;
  transition: background-color 0.22s var(--ease), border-color 0.22s var(--ease);
}
.page-about .about-ledger summary::-webkit-details-marker {
  display: none;
}
.page-about .about-ledger summary::marker {
  content: "";
}
.page-about .about-ledger summary::after {
  content: "+";
  position: absolute;
  right: 10px;
  top: 13px;
  font-family: var(--mono);
  font-size: 14px;
  color: var(--gold-deep);
  transition: transform 0.22s var(--ease);
}
.page-about .about-ledger details[open] > summary::after {
  content: "–";
}
.page-about .about-ledger summary:hover,
.page-about .about-ledger summary:focus-visible {
  background: rgba(201, 162, 39, 0.07);
  border-left-color: var(--gold);
}
.page-about .about-ledger details[open] > summary {
  border-left-color: var(--gold-deep);
}
.page-about .about-ledger .ledger__date {
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--gold-deep);
  text-transform: uppercase;
}
.page-about .about-ledger .ledger__topic {
  font-size: 14.5px;
  line-height: 1.6;
  color: var(--ink);
}
.page-about .about-ledger .ledger__list {
  list-style: none;
  margin: 0;
  padding: 0 12px 16px 12px;
  display: grid;
  gap: 6px;
}
.page-about .about-ledger .ledger__item {
  position: relative;
  padding-left: 16px;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--ink-60);
}
.page-about .about-ledger .ledger__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 1px;
  background: var(--gold);
}

/* ---------- 服务覆盖 ---------- */
.page-about .about-cover {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--gold-line-soft);
  border: 1px solid var(--gold-line-soft);
}
.page-about .about-cover__item {
  background: var(--paper-warm);
  padding: clamp(18px, 2.6vw, 26px);
}
.page-about .about-cover__key {
  display: inline-block;
  font-size: 10px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--celadon);
  margin-bottom: 10px;
}
.page-about .about-cover__title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(16px, 1.8vw, 18px);
  line-height: 1.45;
  margin: 0 0 8px;
  color: var(--ink);
}
.page-about .about-cover__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-60);
}

/* ---------- 团队玻璃板 ---------- */
.page-about .about-team {
  min-width: 0;
}
.page-about .about-team__grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
}
.page-about .about-team__card {
  position: relative;
  padding: 18px 16px 20px;
  background: rgba(255, 255, 255, 0.56);
  border: 1px solid var(--gold-line-soft);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  transition: border-color 0.24s var(--ease), box-shadow 0.24s var(--ease), transform 0.24s var(--ease);
}
.page-about .about-team__card:hover,
.page-about .about-team__card:focus-visible {
  outline: none;
  border-color: var(--gold);
  box-shadow: 0 12px 26px rgba(17, 17, 17, 0.09);
  transform: translateY(-2px);
}
.page-about .about-team__card:focus-visible {
  box-shadow: 0 0 0 2px var(--gold-deep), 0 12px 26px rgba(17, 17, 17, 0.09);
}
.page-about .about-team__no {
  display: block;
  font-size: 10px;
  letter-spacing: 0.16em;
  color: var(--gold-deep);
  margin-bottom: 8px;
}
.page-about .about-team__title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: 17px;
  line-height: 1.4;
  margin: 0 0 6px;
  color: var(--ink);
}
.page-about .about-team__text {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.78;
  color: var(--ink-60);
}
.page-about .about-team__flow {
  margin: 16px 0 0;
  padding: 14px 16px;
  background: var(--charcoal);
  color: var(--paper-72);
  font-size: 13.5px;
  line-height: 1.8;
  border-left: 2px solid var(--gold);
}

/* ---------- 成果表 ---------- */
.page-about .about-credits__wrap {
  border-top: 1px solid var(--gold-line);
}
.page-about .about-credits {
  width: 100%;
  border-collapse: collapse;
  font-size: 14.5px;
}
.page-about .about-credits__caption {
  caption-side: top;
  text-align: left;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--fog);
  padding: 10px 0 12px;
}
.page-about .about-credits th,
.page-about .about-credits td {
  text-align: left;
  vertical-align: top;
  padding: 15px 14px 15px 0;
  border-bottom: 1px solid var(--ink-14);
}
.page-about .about-credits thead th {
  font-family: var(--mono);
  font-weight: 400;
  font-size: 10px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--fog);
  padding-bottom: 10px;
}
.page-about .about-credits tbody tr {
  transition: background-color 0.22s var(--ease);
}
.page-about .about-credits tbody tr:hover {
  background: rgba(201, 162, 39, 0.07);
}
.page-about .about-credits tbody tr:hover td {
  border-bottom-color: var(--gold-line);
}
.page-about .about-credits td:first-child {
  font-family: var(--serif);
  font-weight: 500;
  color: var(--ink);
  width: 26%;
}
.page-about .about-credits td:nth-child(2) {
  color: var(--ink-60);
  line-height: 1.78;
}
.page-about .about-credits td:last-child {
  width: 16%;
  white-space: nowrap;
  color: var(--gold-deep);
}
.page-about .about-credits td .mono {
  font-size: 12px;
  letter-spacing: 0.04em;
}

/* ---------- 收束 CTA ---------- */
.page-about .about-cta {
  margin-top: clamp(32px, 4.5vw, 48px);
  padding: clamp(22px, 3vw, 32px);
  background: var(--paper-warm);
  border: 1px solid var(--gold-line);
  border-left: 3px solid var(--cinnabar);
  display: grid;
  gap: 16px;
}
.page-about .about-cta__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-60);
  max-width: 60ch;
}
.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

/* ---------- 注释与链接 ---------- */
.page-about .about-note {
  margin: clamp(18px, 2.4vw, 24px) 0 0;
  font-size: 13px;
  line-height: 1.8;
  color: var(--fog);
}

/* ---------- 响应式 ---------- */
@media (min-width: 560px) {
  .page-about .about-kinds__item {
    grid-template-columns: 132px minmax(0, 1fr);
    column-gap: 20px;
    align-items: start;
  }
  .page-about .about-kinds__tag {
    grid-row: span 2;
    margin-top: 3px;
  }
  .page-about .about-team__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-cover {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-credits td:first-child {
    width: 24%;
  }
}

@media (min-width: 760px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 1fr);
    align-items: start;
  }
  .page-about .about-split--tight {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.78fr);
  }
  .page-about .about-cover {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 960px) {
  .page-about .about-body__grid {
    grid-template-columns: minmax(0, 1fr) var(--about-rail-w);
    gap: clamp(32px, 4vw, 64px);
    align-items: start;
  }
  .page-about .about-body__rail {
    order: 0;
    position: sticky;
    top: var(--about-sticky-top);
  }
  .page-about .about-team__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1180px) {
  .page-about .about-team__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .about-chapter__title {
    max-width: 22ch;
  }
}

@media (max-width: 639px) {
  .page-about .about-credits thead {
    display: none;
  }
  .page-about .about-credits,
  .page-about .about-credits tbody,
  .page-about .about-credits tr,
  .page-about .about-credits td {
    display: block;
    width: 100%;
  }
  .page-about .about-credits td {
    padding: 0;
    border-bottom: none;
  }
  .page-about .about-credits tbody tr {
    padding: 16px 0;
    border-bottom: 1px solid var(--ink-14);
  }
  .page-about .about-credits td::before {
    content: attr(data-label);
    display: block;
    font-family: var(--mono);
    font-size: 10px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--fog);
    margin-bottom: 4px;
  }
  .page-about .about-credits td + td {
    margin-top: 10px;
  }
  .page-about .about-credits td:first-child,
  .page-about .about-credits td:last-child {
    white-space: normal;
  }
  .page-about .about-cta__actions .button {
    flex: 1 1 auto;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-timeline__item::before,
  .page-about .about-team__card,
  .page-about .about-toc__link,
  .page-about .about-credits tbody tr {
    transition: none;
  }
  .page-about .about-team__card:hover,
  .page-about .about-team__card:focus-visible,
  .page-about .about-timeline__item:hover::before {
    transform: none;
  }
}