.page-about {
  --ab-text-soft: rgba(244, 239, 227, 0.8);
  --ab-text-dim: rgba(244, 239, 227, 0.62);
  background: var(--ink);
  color: var(--cream);
  overflow-x: clip;
}

.page-about h1,
.page-about h2,
.page-about h3 {
  font-weight: 400;
  letter-spacing: 0.01em;
}

/* 面包屑 */
.page-about .ab-crumb {
  padding-top: 1.1rem;
}

.page-about .ab-crumb ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  margin: 0;
  padding: 0;
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--moss);
}

.page-about .ab-crumb li {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.page-about .ab-crumb li + li::before {
  content: "/";
  color: var(--gold-line);
}

.page-about .ab-crumb a {
  color: var(--moss);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .ab-crumb a:hover,
.page-about .ab-crumb a:focus-visible {
  color: var(--gold-lt);
  border-bottom-color: var(--gold-line);
}

/* 首屏 */
.page-about .ab-hero {
  padding-block: clamp(1.5rem, 4.5vw, 3rem) clamp(2.25rem, 6vw, 4rem);
}

.page-about .ab-hero__grid {
  display: grid;
  gap: clamp(1.75rem, 5vw, 3rem);
  align-items: start;
}

.page-about .ab-hero__title {
  margin: 0.7rem 0 0;
  font-size: clamp(2.3rem, 8.6vw, 5.6rem);
  font-weight: 300;
  line-height: 1.04;
  letter-spacing: 0.01em;
  color: var(--cream);
}

.page-about .ab-hero__title span {
  display: block;
  color: var(--gold);
}

.page-about .ab-hero__sub {
  margin: 1.35rem 0 0;
  max-width: 42ch;
  font-size: 1.0625rem;
  line-height: 1.85;
  color: var(--ab-text-soft);
}

.page-about .ab-hero__stats {
  margin: clamp(1.6rem, 4vw, 2.25rem) 0 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--rule-soft);
  border: 1px solid var(--rule-soft);
}

.page-about .ab-hero__stat {
  background: var(--ink);
  padding: 0.9rem 0.85rem 1rem;
}

.page-about .ab-hero__stat dt {
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
  color: var(--moss);
}

.page-about .ab-hero__stat dd {
  margin: 0.4rem 0 0;
  font-size: 0.9rem;
  line-height: 1.2;
}

.page-about .ab-hero__stat dd .num {
  font-family: var(--ff-num);
  font-size: 1.45rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  color: var(--gold);
}

.page-about .ab-hero__unit {
  margin-left: 0.3rem;
  font-size: 0.78rem;
  color: var(--moss);
  letter-spacing: 0.04em;
}

.page-about .ab-hero__media {
  position: relative;
  margin: 0;
  border: 1px solid var(--rule-soft);
  background: var(--ink-2);
}

.page-about .ab-hero__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 5;
  object-fit: cover;
}

.page-about .ab-hero__media::after {
  content: "";
  position: absolute;
  right: 0;
  bottom: 0;
  width: clamp(3rem, 9vw, 5.5rem);
  aspect-ratio: 1;
  border-right: 2px solid var(--gold);
  border-bottom: 2px solid var(--gold);
  pointer-events: none;
}

/* 起点 */
.page-about .ab-origin {
  padding-block: clamp(2.25rem, 6.5vw, 4.5rem);
  border-top: 1px solid var(--rule-soft);
}

.page-about .ab-origin__grid {
  display: grid;
  gap: clamp(1.5rem, 4vw, 2.5rem);
}

.page-about .ab-origin h2 {
  margin: 0.65rem 0 0;
  font-size: clamp(1.45rem, 4vw, 2.35rem);
  line-height: 1.3;
}

.page-about .ab-origin__body p {
  margin: 0 0 1.05rem;
  max-width: 44ch;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--ab-text-soft);
}

.page-about .ab-origin__list {
  list-style: none;
  margin: 1.6rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.9rem;
}

.page-about .ab-origin__list li {
  position: relative;
  padding-left: 1.5rem;
  font-size: 0.95rem;
  line-height: 1.75;
  color: var(--ab-text-dim);
}

.page-about .ab-origin__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 0.5rem;
  height: 0.5rem;
  transform: rotate(45deg);
  background: var(--gold);
}

.page-about .ab-origin__list strong {
  color: var(--cream);
  font-weight: 600;
  margin-right: 0.4rem;
}

/* 时间轴 */
.page-about .ab-tl {
  padding-block: clamp(2.25rem, 6.5vw, 4.5rem);
  background: var(--ink-3);
  border-block: 1px solid var(--rule-soft);
}

.page-about .ab-tl__head {
  max-width: 54ch;
}

.page-about .ab-tl h2 {
  margin: 0.65rem 0 0;
  font-size: clamp(1.45rem, 4vw, 2.35rem);
  line-height: 1.3;
}

.page-about .ab-tl__lede {
  margin: 0.9rem 0 0;
  max-width: 44ch;
  font-size: 1rem;
  line-height: 1.8;
  color: var(--ab-text-soft);
}

.page-about .ab-tl__list {
  list-style: none;
  margin: clamp(1.5rem, 4vw, 2.5rem) 0 0;
  padding: 0;
}

.page-about .ab-tl__item {
  position: relative;
  padding: 1.35rem 0 1.35rem 2.2rem;
}

.page-about .ab-tl__item::before {
  content: "";
  position: absolute;
  left: 0.42rem;
  top: 0;
  bottom: 0;
  width: 1px;
  background: linear-gradient(180deg, var(--rule), var(--rule-soft) 72%, transparent);
}

.page-about .ab-tl__item::after {
  content: "";
  position: absolute;
  left: 0.05rem;
  top: 1.7rem;
  width: 0.8rem;
  height: 0.8rem;
  transform: rotate(45deg);
  background: var(--ink-3);
  border: 1px solid var(--gold-line);
  transition: background 0.22s var(--ease), border-color 0.22s var(--ease);
}

.page-about .ab-tl__item:hover::after,
.page-about .ab-tl__item:focus-within::after {
  background: var(--gold);
  border-color: var(--gold-lt);
}

.page-about .ab-tl__year {
  display: block;
  font-family: var(--ff-num);
  font-size: clamp(1.7rem, 6vw, 2.9rem);
  font-weight: 300;
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--gold);
}

.page-about .ab-tl__title {
  margin: 0.6rem 0 0.4rem;
  font-size: 1.0625rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--cream);
  transition: color 0.2s var(--ease);
}

.page-about .ab-tl__item:hover .ab-tl__title {
  color: var(--gold-lt);
}

.page-about .ab-tl__text {
  margin: 0;
  max-width: 46ch;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--ab-text-dim);
}

.page-about .ab-tl__media {
  list-style: none;
  margin: 1.75rem 0 1.5rem;
  padding: 0;
}

.page-about .ab-tl__media figure {
  margin: 0;
}

.page-about .ab-tl__media img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--rule-soft);
}

.page-about .ab-tl__media figcaption {
  margin-top: 0.7rem;
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  line-height: 1.65;
  color: var(--moss);
}

/* 团队 */
.page-about .ab-team {
  padding-block: clamp(2.25rem, 6.5vw, 4.5rem);
}

.page-about .ab-team__head {
  max-width: 56ch;
}

.page-about .ab-team h2 {
  margin: 0.65rem 0 0;
  font-size: clamp(1.45rem, 4vw, 2.35rem);
  line-height: 1.3;
}

.page-about .ab-team__lede {
  margin: 0.9rem 0 0;
  font-size: 1rem;
  line-height: 1.8;
  color: var(--ab-text-soft);
}

.page-about .ab-team__grid {
  display: grid;
  gap: clamp(1.6rem, 4vw, 2.5rem);
  margin-top: clamp(1.6rem, 4vw, 2.5rem);
}

.page-about .ab-team__bar {
  display: flex;
  height: 58px;
  border: 1px solid var(--rule);
  background: var(--ink-2);
  overflow: hidden;
}

.page-about .ab-team__seg {
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--ff-num);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  border-right: 1px solid rgba(6, 26, 20, 0.5);
  transition: filter 0.2s var(--ease);
}

.page-about .ab-team__seg:last-child {
  border-right: 0;
}

.page-about .ab-team__seg--data {
  flex: 22;
  background: var(--gold);
  color: var(--ink);
}

.page-about .ab-team__seg--dev {
  flex: 14;
  background: var(--gold-line);
  color: var(--cream);
}

.page-about .ab-team__seg--support {
  flex: 10;
  background: var(--cyan);
  color: var(--ink);
}

.page-about .ab-team__seg--content {
  flex: 12;
  background: var(--orange);
  color: var(--ink);
}

.page-about .ab-team__seg--ops {
  flex: 10;
  background: var(--moss);
  color: var(--ink);
}

.page-about .ab-team__seg:hover {
  filter: brightness(1.16);
}

.page-about .ab-team__legend {
  list-style: none;
  margin: 1.15rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.65rem;
}

.page-about .ab-team__legend li {
  display: grid;
  grid-template-columns: 0.7rem auto 1fr;
  align-items: baseline;
  column-gap: 0.6rem;
  row-gap: 0.1rem;
  font-size: 0.9rem;
  line-height: 1.6;
  padding-bottom: 0.55rem;
  border-bottom: 1px solid var(--rule-soft);
}

.page-about .ab-team__legend li:last-child {
  border-bottom: 0;
}

.page-about .ab-team__dot {
  width: 0.55rem;
  height: 0.55rem;
  transform: rotate(45deg);
  align-self: center;
}

.page-about .ab-team__legend li:nth-child(1) .ab-team__dot {
  background: var(--gold);
}

.page-about .ab-team__legend li:nth-child(2) .ab-team__dot {
  background: var(--gold-line);
}

.page-about .ab-team__legend li:nth-child(3) .ab-team__dot {
  background: var(--cyan);
}

.page-about .ab-team__legend li:nth-child(4) .ab-team__dot {
  background: var(--orange);
}

.page-about .ab-team__legend li:nth-child(5) .ab-team__dot {
  background: var(--moss);
}

.page-about .ab-team__name {
  color: var(--cream);
  font-weight: 600;
}

.page-about .ab-team__val {
  font-family: var(--ff-num);
  color: var(--gold-lt);
  justify-self: start;
}

.page-about .ab-team__desc {
  grid-column: 2 / -1;
  color: var(--ab-text-dim);
  font-size: 0.8125rem;
  line-height: 1.6;
}

.page-about .ab-team__media {
  margin: 0;
}

.page-about .ab-team__media img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--rule-soft);
}

.page-about .ab-team__media figcaption {
  margin-top: 0.75rem;
  font-size: 0.78rem;
  line-height: 1.7;
  color: var(--moss);
  letter-spacing: 0.03em;
}

/* 目录 */
.page-about .ab-cat {
  padding-block: clamp(2.25rem, 6.5vw, 4.5rem);
  background: var(--ink-2);
  border-block: 1px solid var(--rule-soft);
}

.page-about .ab-cat h2 {
  margin: 0.65rem 0 0;
  font-size: clamp(1.45rem, 4vw, 2.35rem);
  line-height: 1.3;
}

.page-about .ab-cat__lede {
  margin: 0.9rem 0 0;
  max-width: 48ch;
  font-size: 1rem;
  line-height: 1.8;
  color: var(--ab-text-soft);
}

.page-about .ab-cat__grid {
  display: grid;
  gap: 1px;
  margin-top: clamp(1.5rem, 4vw, 2.25rem);
  background: var(--rule-soft);
  border: 1px solid var(--rule-soft);
}

.page-about .ab-cat__card {
  background: var(--ink-2);
  padding: 1.25rem 1.1rem 1.4rem;
  transition: background 0.24s var(--ease);
}

.page-about .ab-cat__card:hover {
  background: var(--ink-3);
}

.page-about .ab-cat__card h3 {
  margin: 0.6rem 0 0.45rem;
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--cream);
}

.page-about .ab-cat__card p {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--ab-text-dim);
}

.page-about .ab-cat__note {
  margin: 1.25rem 0 0;
  font-size: 0.875rem;
  line-height: 1.8;
  color: var(--moss);
  max-width: 54ch;
}

/* 校验与支持 */
.page-about .ab-check {
  padding-block: clamp(2.25rem, 6.5vw, 4.5rem);
}

.page-about .ab-check__head {
  max-width: 54ch;
}

.page-about .ab-check h2 {
  margin: 0.65rem 0 0;
  font-size: clamp(1.45rem, 4vw, 2.35rem);
  line-height: 1.3;
}

.page-about .ab-check__lede {
  margin: 0.9rem 0 0;
  font-size: 1rem;
  line-height: 1.8;
  color: var(--ab-text-soft);
}

.page-about .ab-check__steps {
  display: grid;
  gap: 1rem;
  margin-top: clamp(1.5rem, 4vw, 2.25rem);
}

.page-about .ab-check__step {
  border-top: 2px solid var(--cyan);
  background: var(--ink-2);
  padding: 1.1rem 1.05rem 1.25rem;
}

.page-about .ab-check__idx {
  margin: 0;
  font-family: var(--ff-num);
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .ab-check__step h3 {
  margin: 0.55rem 0 0.45rem;
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--cream);
}

.page-about .ab-check__step p {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--ab-text-dim);
}

.page-about .ab-check__metrics {
  margin: clamp(1.5rem, 4vw, 2rem) 0 0;
  display: grid;
  gap: 0;
  border-top: 1px solid var(--rule-soft);
}

.page-about .ab-check__metrics div {
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--rule-soft);
}

.page-about .ab-check__metrics dt {
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
  color: var(--gold);
  margin-bottom: 0.3rem;
}

.page-about .ab-check__metrics dd {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--ab-text-soft);
}

.page-about .ab-check__metrics .num {
  font-family: var(--ff-num);
  font-weight: 600;
  color: var(--cyan);
}

/* 协作 */
.page-about .ab-coop {
  padding-block: clamp(2.25rem, 6.5vw, 4.5rem);
  background: linear-gradient(180deg, rgba(216, 168, 78, 0.07), transparent 62%), var(--ink-2);
  border-block: 1px solid var(--rule-soft);
}

.page-about .ab-coop__grid {
  display: grid;
  gap: clamp(1.75rem, 4vw, 3rem);
}

.page-about .ab-coop h2 {
  margin: 0.65rem 0 1rem;
  font-size: clamp(1.45rem, 4vw, 2.35rem);
  line-height: 1.3;
}

.page-about .ab-coop p {
  margin: 0 0 1rem;
  max-width: 46ch;
  font-size: 1rem;
  line-height: 1.8;
  color: var(--ab-text-soft);
}

.page-about .ab-coop__links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem 1.6rem;
  margin: 1.5rem 0 0;
}

.page-about .ab-coop__links a {
  font-size: 0.9375rem;
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(44, 224, 194, 0.35);
  padding-bottom: 0.15rem;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

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

.page-about .ab-coop__stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--rule-soft);
  border: 1px solid var(--rule-soft);
  align-content: start;
}

.page-about .ab-coop__stats li {
  background: var(--ink);
  padding: 1rem 1.05rem;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.15rem 0.6rem;
}

.page-about .ab-coop__stats .num {
  font-family: var(--ff-num);
  font-size: 1.55rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  color: var(--gold);
  line-height: 1.1;
}

.page-about .ab-coop__unit {
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--ab-text-dim);
}

/* 收束 */
.page-about .ab-cta {
  padding-block: clamp(2.5rem, 7vw, 5rem);
}

.page-about .ab-cta__inner {
  max-width: 62ch;
}

.page-about .ab-cta h2 {
  margin: 0;
  font-size: clamp(1.55rem, 4.6vw, 2.75rem);
  font-weight: 300;
  line-height: 1.28;
}

.page-about .ab-cta p {
  margin: 1rem 0 0;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--ab-text-soft);
}

.page-about .ab-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin-top: 1.75rem;
}

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

@media (min-width: 760px) {
  .page-about .ab-check__steps {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .ab-check__metrics {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    column-gap: 1.5rem;
  }
}

@media (min-width: 820px) {
  .page-about .ab-tl__item {
    display: grid;
    grid-template-columns: 9.5rem minmax(0, 1fr);
    column-gap: clamp(1.5rem, 4vw, 3rem);
    align-items: start;
    padding: 1.7rem 0 1.7rem 2.4rem;
  }

  .page-about .ab-tl__year {
    grid-column: 1;
    grid-row: 1;
  }

  .page-about .ab-tl__content {
    grid-column: 2;
    grid-row: 1;
  }

  .page-about .ab-tl__title {
    margin-top: 0.2rem;
  }

  .page-about .ab-tl__item::after {
    top: 2.15rem;
  }
}

@media (min-width: 900px) {
  .page-about .ab-hero__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    column-gap: clamp(2rem, 4vw, 4.5rem);
  }

  .page-about .ab-hero__media {
    margin-top: 1.75rem;
  }

  .page-about .ab-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .ab-origin__grid {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
    column-gap: clamp(2rem, 5vw, 4.5rem);
  }

  .page-about .ab-team__grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.82fr);
    column-gap: clamp(2rem, 4vw, 3.5rem);
    align-items: start;
  }

  .page-about .ab-coop__grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    column-gap: clamp(2rem, 5vw, 4rem);
  }
}

@media (min-width: 1024px) {
  .page-about .ab-cat__grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    transition: none !important;
  }
}