.page-about {
  --ab-rule: rgba(122, 74, 43, .3);
  --ab-line-soft: rgba(122, 74, 43, .16);
}

/* 面包屑 */
.page-about .gh-breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .35rem;
  list-style: none;
  margin: 0 0 clamp(1.1rem, 3vw, 1.9rem);
  padding: 0;
  font-family: var(--gh-font-mono);
  font-size: .72rem;
  letter-spacing: .08em;
  color: var(--gh-stone);
}

.page-about .gh-breadcrumb li + li::before {
  content: "/";
  margin-right: .35rem;
  color: var(--gh-copper);
}

.page-about .gh-breadcrumb a {
  color: var(--gh-forest);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--gh-ease);
}

.page-about .gh-breadcrumb a:hover,
.page-about .gh-breadcrumb a:focus-visible {
  border-bottom-color: var(--gh-gold);
}

/* 首屏 */
.page-about .ab-hero {
  position: relative;
  padding-top: clamp(1rem, 2.4vw, 1.7rem);
  padding-bottom: clamp(1.8rem, 4.5vw, 3.2rem);
}

.page-about .ab-hero__grid {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.5rem, 4vw, 2.8rem);
  align-items: start;
  overflow: hidden;
}

.page-about .ab-hero__grid::before {
  content: "";
  position: absolute;
  inset: -3rem -10% auto auto;
  width: 62%;
  height: 116%;
  background: linear-gradient(148deg, rgba(201, 137, 44, .22), rgba(78, 107, 74, .13) 52%, rgba(201, 137, 44, 0) 80%);
  clip-path: polygon(40% 0, 100% 0, 100% 100%, 0 100%);
  pointer-events: none;
  z-index: 0;
}

.page-about .ab-hero__copy {
  position: relative;
  z-index: 1;
}

.page-about .ab-hero h1 {
  margin: 0 0 clamp(.9rem, 2.2vw, 1.3rem);
  font-family: var(--gh-font-display);
  font-weight: 700;
  font-size: clamp(1.95rem, 5.2vw, 3.4rem);
  line-height: 1.18;
  letter-spacing: -.015em;
  color: var(--gh-forest);
}

.page-about .ab-hero__lede {
  max-width: 46ch;
  margin: 0 0 clamp(1.2rem, 3vw, 1.7rem);
  font-size: clamp(.98rem, 1.6vw, 1.08rem);
  line-height: 1.8;
  color: rgba(20, 19, 16, .84);
}

.page-about .ab-hero__stats {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(7.2rem, 1fr));
  gap: .9rem 1rem;
  margin: 0 0 clamp(1.4rem, 3vw, 2rem);
  padding: 1rem 0 0;
  border-top: 1px solid var(--ab-rule);
}

.page-about .ab-stat__line {
  display: flex;
  align-items: baseline;
  gap: .12rem;
}

.page-about .ab-stat__num {
  font-family: var(--gh-font-mono);
  font-weight: 600;
  font-size: clamp(1.3rem, 2.6vw, 1.7rem);
  line-height: 1.1;
  color: var(--gh-copper);
}

.page-about .ab-stat__unit {
  font-family: var(--gh-font-mono);
  font-size: .76rem;
  color: var(--gh-stone);
}

.page-about .ab-stat__k {
  display: block;
  margin-top: .35rem;
  font-size: .8rem;
  line-height: 1.6;
  color: var(--gh-stone);
}

.page-about .ab-hero__media {
  position: relative;
  z-index: 1;
  margin: 0;
  aspect-ratio: 3 / 2;
  background: var(--gh-forest);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 2.1rem), 0 100%);
  box-shadow: 0 20px 38px -30px rgba(15, 36, 28, .85);
}

.page-about .ab-hero__media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.92) contrast(1.04);
}

.page-about .gh-converge {
  height: 3px;
  margin-top: clamp(1.5rem, 4vw, 2.5rem);
  background: linear-gradient(90deg, var(--gh-copper) 0%, var(--gh-gold) 26%, rgba(232, 180, 90, 0) 82%);
  clip-path: polygon(0 0, 100% 0, 93% 100%, 0 100%);
}

/* 档案索引 + 画板 */
.page-about .ab-ledger {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.6rem, 4vw, 2.4rem);
  align-items: start;
  padding-bottom: clamp(2.6rem, 6vw, 4.5rem);
}

.page-about .ab-index {
  align-self: start;
}

.page-about .ab-index__list {
  list-style: none;
  display: grid;
  gap: .1rem;
  margin: .9rem 0 0;
  padding: 0 0 .3rem;
}

.page-about .ab-index a {
  display: grid;
  grid-template-columns: 1.9rem minmax(0, 1fr);
  gap: .55rem;
  align-items: baseline;
  padding: .55rem .5rem .55rem .65rem;
  border-left: 2px solid rgba(122, 74, 43, .18);
  color: var(--gh-forest);
  text-decoration: none;
  transition: background var(--gh-ease), border-color var(--gh-ease), transform var(--gh-ease);
}

.page-about .ab-index a:hover,
.page-about .ab-index a:focus-visible {
  background: rgba(232, 180, 90, .16);
  border-left-color: var(--gh-gold);
  transform: translateX(2px);
}

.page-about .ab-index__no {
  font-family: var(--gh-font-mono);
  font-size: .72rem;
  letter-spacing: .12em;
  color: var(--gh-copper);
}

.page-about .ab-index__label {
  display: block;
  font-size: .88rem;
  font-weight: 600;
  line-height: 1.4;
}

.page-about .ab-index__meta {
  display: block;
  margin-top: .18rem;
  font-family: var(--gh-font-mono);
  font-size: .66rem;
  letter-spacing: .05em;
  color: var(--gh-stone);
}

.page-about .ab-boards {
  display: grid;
  gap: clamp(1.1rem, 3vw, 1.9rem);
}

.page-about .ab-board {
  position: relative;
  padding: clamp(1.15rem, 3vw, 2.1rem);
  background: var(--gh-paper);
  border-top: 1px solid rgba(122, 74, 43, .38);
  box-shadow: 0 1px 2px rgba(20, 19, 16, .05);
  scroll-margin-top: 5.5rem;
  transition: transform var(--gh-ease), box-shadow var(--gh-ease);
}

.page-about .ab-board::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: repeating-linear-gradient(0deg, rgba(122, 74, 43, .04) 0, rgba(122, 74, 43, .04) 1px, transparent 1px, transparent 4px);
  opacity: .65;
}

.page-about .ab-board:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 26px -20px rgba(15, 36, 28, .7);
}

.page-about .ab-board__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: .5rem .9rem;
  margin-bottom: clamp(.9rem, 2vw, 1.25rem);
  padding-bottom: .7rem;
  border-bottom: 1px solid var(--ab-line-soft);
}

.page-about .ab-board__no {
  font-family: var(--gh-font-mono);
  font-size: .72rem;
  letter-spacing: .18em;
  color: var(--gh-copper);
}

.page-about .ab-board__title {
  margin: 0;
  font-family: var(--gh-font-display);
  font-weight: 700;
  font-size: clamp(1.22rem, 2.8vw, 1.72rem);
  line-height: 1.3;
  letter-spacing: -.01em;
  color: var(--gh-forest);
}

.page-about .ab-board h3 {
  margin: 0 0 .3rem;
  font-size: .96rem;
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--gh-forest);
}

.page-about .ab-board > p {
  margin: 0 0 .9rem;
  max-width: 70ch;
  font-size: .94rem;
  line-height: 1.8;
  color: rgba(20, 19, 16, .82);
}

.page-about .ab-board > p:last-of-type {
  margin-bottom: 1rem;
}

.page-about .ab-board__body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1rem, 3vw, 1.8rem);
  align-items: start;
}

.page-about .ab-board__copy p {
  margin: 0 0 .9rem;
  max-width: 68ch;
  font-size: .94rem;
  line-height: 1.8;
  color: rgba(20, 19, 16, .82);
}

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

.page-about .ab-board__fig {
  margin: 0;
  aspect-ratio: 1 / 1;
  background: var(--gh-forest);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 1.6rem 100%);
}

.page-about .ab-board__fig--wide {
  aspect-ratio: 3 / 2;
  clip-path: polygon(0 0, 100% 0, 100% 86%, 0 100%);
}

.page-about .ab-board__fig img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.94);
}

/* 时间轴 */
.page-about .ab-timeline {
  position: relative;
  list-style: none;
  display: grid;
  gap: clamp(1rem, 2.4vw, 1.5rem);
  margin: 0;
  padding: 0;
}

.page-about .ab-timeline::before {
  content: "";
  position: absolute;
  left: 3.15rem;
  top: .45rem;
  bottom: .45rem;
  width: 1px;
  background: linear-gradient(180deg, rgba(122, 74, 43, .5), rgba(122, 74, 43, .05));
}

.page-about .ab-timeline li {
  position: relative;
  display: grid;
  grid-template-columns: 3.15rem minmax(0, 1fr);
  gap: clamp(.7rem, 2vw, 1.2rem);
  align-items: start;
}

.page-about .ab-timeline li::before {
  content: "";
  position: absolute;
  left: calc(3.15rem - .27rem);
  top: .44rem;
  width: .54rem;
  height: .54rem;
  border-radius: 50%;
  background: var(--gh-mist);
  border: 1.5px solid var(--gh-gold);
}

.page-about .ab-timeline__year {
  font-family: var(--gh-font-mono);
  font-size: .78rem;
  letter-spacing: .05em;
  color: var(--gh-copper);
  padding-top: .1rem;
}

.page-about .ab-timeline li p {
  margin: 0;
  font-size: .9rem;
  line-height: 1.75;
  color: rgba(20, 19, 16, .8);
}

/* 团队 */
.page-about .ab-crew {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(11rem, 1fr));
  gap: 1px;
  margin: 0 0 clamp(1.1rem, 2.6vw, 1.6rem);
  padding: 0;
  background: var(--ab-line-soft);
  border: 1px solid var(--ab-line-soft);
}

.page-about .ab-crew li {
  background: var(--gh-paper);
  padding: .9rem 1rem 1rem;
}

.page-about .ab-crew__num {
  display: block;
  font-family: var(--gh-font-mono);
  font-weight: 600;
  font-size: 1.45rem;
  line-height: 1.1;
  color: var(--gh-copper);
}

.page-about .ab-crew__k {
  display: block;
  margin: .2rem 0 .4rem;
  font-size: .92rem;
  font-weight: 700;
  color: var(--gh-forest);
}

.page-about .ab-crew li p {
  margin: 0;
  font-size: .85rem;
  line-height: 1.7;
  color: rgba(20, 19, 16, .78);
}

/* 场景 */
.page-about .ab-scenes {
  list-style: none;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 0;
  padding: 0;
  background: var(--ab-line-soft);
  border: 1px solid var(--ab-line-soft);
}

.page-about .ab-scenes li {
  position: relative;
  background: var(--gh-paper);
  padding: 1rem 1.05rem 1.1rem;
}

.page-about .ab-scenes li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 2.2rem;
  height: 2px;
  background: var(--gh-gold);
  opacity: .6;
}

.page-about .ab-scenes p {
  margin: 0;
  font-size: .86rem;
  line-height: 1.72;
  color: rgba(20, 19, 16, .8);
}

/* 合作 */
.page-about .ab-partners {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1rem, 3vw, 2rem);
  align-items: start;
}

.page-about .ab-figures {
  list-style: none;
  display: grid;
  gap: .8rem;
  margin: 0;
  padding: 0;
}

.page-about .ab-figures li {
  padding: .75rem 0 .75rem .9rem;
  border-left: 2px solid var(--gh-gold);
  background: linear-gradient(90deg, rgba(232, 180, 90, .14), rgba(232, 180, 90, 0) 76%);
}

.page-about .ab-figures__v {
  display: block;
  font-family: var(--gh-font-mono);
  font-weight: 600;
  font-size: 1.2rem;
  color: var(--gh-forest);
}

.page-about .ab-figures__k {
  display: block;
  margin-top: .2rem;
  font-size: .8rem;
  line-height: 1.6;
  color: var(--gh-stone);
}

/* 服务入口 */
.page-about .ab-links {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: .6rem;
  margin-top: .4rem;
}

.page-about .ab-links a {
  display: block;
  padding: .8rem 1rem .85rem;
  border: 1px solid rgba(122, 74, 43, .3);
  background: rgba(252, 247, 238, .6);
  color: var(--gh-forest);
  font-size: .9rem;
  font-weight: 600;
  text-decoration: none;
  transition: border-color var(--gh-ease), background var(--gh-ease), transform var(--gh-ease);
}

.page-about .ab-links a:hover,
.page-about .ab-links a:focus-visible {
  border-color: var(--gh-gold);
  background: rgba(232, 180, 90, .15);
  transform: translateY(-2px);
}

.page-about .ab-links a span {
  display: block;
  margin-bottom: .25rem;
  font-family: var(--gh-font-mono);
  font-size: .68rem;
  letter-spacing: .12em;
  color: var(--gh-copper);
}

/* 键盘焦点 */
.page-about a:focus-visible,
.page-about .gh-btn:focus-visible {
  outline: 2px solid var(--gh-bright);
  outline-offset: 2px;
}

/* 窄屏：索引横向排布 */
@media (max-width: 59.99rem) {
  .page-about .ab-index__list {
    grid-auto-flow: column;
    grid-auto-columns: minmax(9rem, max-content);
    overflow-x: auto;
    padding-bottom: .45rem;
  }

  .page-about .ab-index a {
    border-left: 0;
    border-bottom: 2px solid rgba(122, 74, 43, .18);
    padding: .5rem .6rem .6rem;
  }

  .page-about .ab-index a:hover,
  .page-about .ab-index a:focus-visible {
    border-left-color: transparent;
    border-bottom-color: var(--gh-gold);
    transform: translateY(-2px);
  }
}

@media (max-width: 26rem) {
  .page-about .ab-hero__stats {
    grid-template-columns: 1fr;
  }
}

/* 桌面栅格 */
@media (min-width: 46rem) {
  .page-about .ab-board--split .ab-board__body {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, .9fr);
  }

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

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

@media (min-width: 48rem) {
  .page-about .ab-partners {
    grid-template-columns: minmax(0, .85fr) minmax(0, 1.15fr);
  }
}

@media (min-width: 60rem) {
  .page-about .ab-ledger {
    grid-template-columns: 11.5rem minmax(0, 1fr);
    gap: clamp(2rem, 4.5vw, 4rem);
  }

  .page-about .ab-index {
    position: sticky;
    top: 6rem;
  }
}

@media (min-width: 62rem) {
  .page-about .ab-hero__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, .88fr);
    align-items: center;
  }

  .page-about .ab-board {
    padding: clamp(1.4rem, 2.4vw, 2.1rem);
  }
}

@media (min-width: 74rem) {
  .page-about .ab-scenes {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-board,
  .page-about .ab-index a,
  .page-about .ab-links a {
    transition: none;
  }

  .page-about .ab-board:hover,
  .page-about .ab-index a:hover,
  .page-about .ab-links a:hover {
    transform: none;
  }
}