.page-about {
  --ab-pad: clamp(16px, 4vw, 40px);
  --ab-gap: clamp(28px, 4vw, 52px);
}

/* ---------- 面包屑 ---------- */

.page-about .ab-crumbrow {
  padding-top: calc(var(--header-h) + 18px);
  padding-bottom: 6px;
  position: relative;
  z-index: 2;
}

/* ---------- 首屏 ---------- */

.page-about .ab-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(26px, 5vw, 52px) 0 clamp(52px, 8vw, 96px);
  background:
    radial-gradient(115% 72% at 82% 0%, rgba(59, 232, 198, 0.11), transparent 58%),
    radial-gradient(85% 62% at 2% 100%, rgba(30, 156, 134, 0.14), transparent 62%),
    var(--ink);
}

.page-about .ab-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, var(--line-soft) 1px, transparent 1px),
    linear-gradient(to bottom, var(--line-soft) 1px, transparent 1px);
  background-size: 92px 92px;
  opacity: 0.32;
  -webkit-mask-image: linear-gradient(to bottom, #000 0%, transparent 76%);
  mask-image: linear-gradient(to bottom, #000 0%, transparent 76%);
  pointer-events: none;
}

.page-about .ab-hero__grid {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 5vw, 48px);
}

.page-about .ab-hero__title {
  margin: 14px 0 0;
  font-size: clamp(2rem, 7.2vw, var(--fs-72));
  line-height: 1.04;
  letter-spacing: -0.012em;
  font-weight: 900;
  max-width: 18ch;
}

.page-about .ab-hero__lead {
  margin-top: clamp(18px, 3vw, 28px);
  max-width: 36em;
  color: var(--muted);
  line-height: 1.85;
}

.page-about .ab-hero__plaque {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: clamp(20px, 3vw, 28px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--glass-2);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
}

.page-about .ab-hero__plaque::before,
.page-about .ab-hero__plaque::after {
  content: "";
  position: absolute;
  width: 20px;
  height: 20px;
  pointer-events: none;
}

.page-about .ab-hero__plaque::before {
  top: -1px;
  left: -1px;
  border-top: 2px solid var(--cyan);
  border-left: 2px solid var(--cyan);
}

.page-about .ab-hero__plaque::after {
  right: -1px;
  bottom: -1px;
  border-right: 2px solid var(--cyan);
  border-bottom: 2px solid var(--cyan);
}

.page-about .ab-plaque__key {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.2em;
  color: var(--muted);
}

.page-about .ab-plaque__val {
  font-family: var(--font-mono);
  font-size: clamp(2.6rem, 9vw, var(--fs-72));
  line-height: 1;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--cyan);
}

.page-about .ab-plaque__rule {
  display: block;
  height: 1px;
  background: var(--line);
}

.page-about .ab-plaque__row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 12px;
  align-items: baseline;
  font-size: var(--fs-14);
}

.page-about .ab-plaque__row em {
  font-style: normal;
  color: var(--muted);
}

.page-about .ab-plaque__row strong {
  font-family: var(--font-mono);
  font-size: var(--fs-16);
  font-weight: 700;
  color: var(--text);
}

/* ---------- 通用小标题 ---------- */

.page-about .ab-sect__head {
  max-width: 64ch;
}

.page-about .ab-sect__sub {
  margin-top: 14px;
  max-width: 50ch;
  color: var(--muted);
}

/* ---------- 01 运营起点 ---------- */

.page-about .ab-split {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(20px, 4vw, 40px);
}

.page-about .ab-split__body .bs-p + .bs-p {
  margin-top: 18px;
}

.page-about .ab-split__body .bs-p {
  max-width: 40em;
}

.page-about .ab-factrow {
  list-style: none;
  margin: clamp(26px, 4vw, 38px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
}

.page-about .ab-factrow li {
  background: var(--ink-2);
  padding: 16px 18px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.page-about .ab-factrow__k {
  font-size: var(--fs-12);
  letter-spacing: 0.08em;
  color: var(--muted);
}

.page-about .ab-factrow__v {
  font-family: var(--font-mono);
  font-size: var(--fs-20);
  font-weight: 700;
  color: var(--cyan);
}

/* ---------- 02 覆盖范围 ---------- */

.page-about .ab-cover {
  background: linear-gradient(180deg, var(--ink) 0%, var(--ink-2) 48%, var(--ink) 100%);
  border-top: 1px solid var(--line-soft);
  border-bottom: 1px solid var(--line-soft);
}

.page-about .ab-cover__grid {
  margin-top: var(--ab-gap);
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 4vw, 44px);
}

.page-about .ab-cover__map {
  margin: 0;
  padding: 14px;
  border: 1px solid var(--line);
  background: var(--ink-2);
}

.page-about .ab-cover__map img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  filter: saturate(0.82) contrast(1.06);
}

.page-about .ab-cover__cap {
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.04em;
  color: var(--muted);
}

.page-about .ab-cover__group + .ab-cover__group {
  margin-top: 26px;
}

.page-about .ab-cover__label {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  font-size: var(--fs-14);
  font-weight: 700;
  color: var(--text);
}

.page-about .ab-dot {
  flex: none;
  display: inline-block;
  width: 8px;
  height: 8px;
}

.page-about .ab-dot--cyan {
  background: var(--cyan);
}

.page-about .ab-dot--orange {
  background: var(--orange);
}

.page-about .ab-chips {
  list-style: none;
  margin: 12px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .ab-chips li {
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  letter-spacing: 0.04em;
  padding: 7px 14px;
  border: 1px solid var(--line);
  background: var(--panel);
  color: var(--text);
  transition: border-color 0.24s var(--ease), color 0.24s var(--ease);
}

.page-about .ab-chips--major li {
  border-color: rgba(59, 232, 198, 0.42);
}

.page-about .ab-chips--minor li {
  border-color: rgba(255, 122, 47, 0.34);
}

.page-about .ab-chips li:hover {
  border-color: var(--cyan);
  color: var(--cyan);
}

.page-about .ab-metabar {
  margin: clamp(26px, 4vw, 36px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1px;
  background: var(--line-soft);
  border-top: 1px solid var(--line-soft);
  border-bottom: 1px solid var(--line-soft);
}

.page-about .ab-metabar > div {
  background: var(--ink-2);
  padding: 14px 16px;
}

.page-about .ab-metabar dt {
  font-size: var(--fs-12);
  letter-spacing: 0.06em;
  color: var(--muted);
}

.page-about .ab-metabar dd {
  margin: 6px 0 0;
  font-family: var(--font-mono);
  font-size: var(--fs-20);
  font-weight: 700;
  color: var(--text);
}

/* ---------- 03 团队 ---------- */

.page-about .ab-team__figure {
  margin: var(--ab-gap) 0 0;
  border: 1px solid var(--line);
  background: var(--ink-2);
  overflow: hidden;
}

.page-about .ab-team__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  aspect-ratio: 2 / 1;
  object-fit: cover;
}

.page-about .ab-team__figure figcaption {
  padding: 12px 16px;
  border-top: 1px solid var(--line-soft);
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.04em;
  color: var(--muted);
}

.page-about .ab-roles {
  margin-top: clamp(18px, 3vw, 26px);
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.page-about .ab-role {
  border: 1px solid var(--line);
  background: var(--panel);
  transition: border-color 0.24s var(--ease);
}

.page-about .ab-role:hover {
  border-color: var(--cyan);
}

.page-about .ab-role[open] {
  border-color: var(--line);
  box-shadow: inset 3px 0 0 var(--orange);
}

.page-about .ab-role__sum {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 14px;
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
}

.page-about .ab-role__sum::-webkit-details-marker {
  display: none;
}

.page-about .ab-role__num {
  font-family: var(--font-mono);
  font-size: var(--fs-28);
  font-weight: 700;
  line-height: 1;
  color: var(--cyan);
}

.page-about .ab-role__name {
  font-size: var(--fs-16);
  font-weight: 700;
  color: var(--text);
}

.page-about .ab-role__chev {
  width: 10px;
  height: 10px;
  margin-top: -4px;
  border-right: 2px solid var(--muted);
  border-bottom: 2px solid var(--muted);
  transform: rotate(45deg);
  transition: transform 0.24s var(--ease), border-color 0.24s var(--ease);
}

.page-about .ab-role[open] .ab-role__chev {
  margin-top: 4px;
  transform: rotate(225deg);
  border-color: var(--orange);
}

.page-about .ab-role__body {
  padding: 0 18px 18px;
}

.page-about .ab-role__body p {
  margin: 0;
  max-width: 42em;
  font-size: var(--fs-14);
  line-height: 1.85;
  color: var(--muted);
}

.page-about .ab-cadence {
  list-style: none;
  margin: clamp(26px, 4vw, 38px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 1px;
  background: var(--line-soft);
}

.page-about .ab-cadence li {
  background: var(--ink-2);
  padding: 16px 18px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.page-about .ab-cadence__when {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.18em;
  color: var(--orange);
}

.page-about .ab-cadence__what {
  font-size: var(--fs-14);
  color: var(--text);
}

/* ---------- 04 版本演进 ---------- */

.page-about .ab-tl__media {
  margin: var(--ab-gap) 0 0;
}

.page-about .ab-tl__media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  aspect-ratio: 12 / 5;
  object-fit: cover;
  border: 1px solid var(--line);
}

.page-about .ab-tl__scale {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-top: 14px;
}

.page-about .ab-tl__scale-tag {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.12em;
  color: var(--muted);
  white-space: nowrap;
}

.page-about .ab-tl__scale-bar {
  flex: 1 1 auto;
  height: 1px;
  background: linear-gradient(to right, var(--teal), var(--cyan));
  opacity: 0.7;
}

.page-about .ab-tl__scroller {
  margin-top: clamp(24px, 4vw, 38px);
  overflow-x: auto;
  overflow-y: hidden;
  padding-bottom: 22px;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
  scrollbar-color: var(--grid) transparent;
}

.page-about .ab-tl__scroller::-webkit-scrollbar {
  height: 6px;
}

.page-about .ab-tl__scroller::-webkit-scrollbar-thumb {
  background: var(--grid);
}

.page-about .ab-tl__track {
  position: relative;
  display: flex;
  align-items: flex-start;
  list-style: none;
  margin: 0;
  padding: 0 var(--ab-pad) 0;
  min-width: max-content;
}

.page-about .ab-tl__track::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 23px;
  height: 1px;
  background: linear-gradient(to right, transparent, var(--cyan) 6%, var(--cyan) 94%, transparent);
  opacity: 0.42;
  pointer-events: none;
}

.page-about .ab-tl__node {
  flex: 0 0 clamp(230px, 76vw, 288px);
  padding-right: 26px;
  scroll-snap-align: start;
}

.page-about .ab-tl__dot {
  display: block;
  width: 10px;
  height: 10px;
  margin: 18px 0 16px;
  border: 2px solid var(--cyan);
  border-radius: 50%;
  background: var(--ink);
  transition: background 0.24s var(--ease), box-shadow 0.24s var(--ease);
}

.page-about .ab-tl__node:hover .ab-tl__dot {
  background: var(--cyan);
  box-shadow: 0 0 0 6px rgba(59, 232, 198, 0.14);
}

.page-about .ab-tl__ver {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.22em;
  color: var(--orange);
}

.page-about .ab-tl__title {
  margin: 0 0 10px;
  font-size: var(--fs-16);
  font-weight: 700;
  line-height: 1.45;
  color: var(--text);
}

.page-about .ab-tl__desc {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 05 整理标准 ---------- */

.page-about .ab-std {
  margin-top: var(--ab-gap);
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(22px, 3vw, 32px);
}

.page-about .ab-std__item {
  padding-top: 18px;
  border-top: 2px solid var(--grid);
}

.page-about .ab-std__item--a {
  border-top-color: var(--teal);
}

.page-about .ab-std__item--b {
  border-top-color: var(--cyan);
}

.page-about .ab-std__item--c {
  border-top-color: var(--orange);
}

.page-about .ab-std__n {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.22em;
  color: var(--muted);
}

.page-about .ab-std__h {
  margin: 12px 0 12px;
  font-size: var(--fs-20);
  font-weight: 700;
  color: var(--text);
}

.page-about .ab-std__p {
  margin: 0;
  font-size: var(--fs-16);
  line-height: 1.85;
  color: var(--muted);
}

/* ---------- 收束 ---------- */

.page-about .ab-cta__inner {
  border: 1px solid var(--line);
  background:
    radial-gradient(120% 140% at 88% 10%, rgba(59, 232, 198, 0.09), transparent 58%),
    var(--panel);
  padding: clamp(26px, 4vw, 48px);
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(22px, 3vw, 36px);
}

.page-about .ab-cta__p {
  margin-top: 14px;
  max-width: 44em;
  color: var(--muted);
}

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

/* ---------- 媒体查询 ---------- */

@media (min-width: 720px) {
  .page-about .ab-factrow {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .ab-roles {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
  }

  .page-about .ab-role__sum {
    grid-template-columns: 1fr;
    grid-template-rows: auto auto;
    gap: 10px;
    align-items: start;
    position: relative;
  }

  .page-about .ab-role__chev {
    position: absolute;
    top: 22px;
    right: 18px;
  }

  .page-about .ab-role__body {
    padding: 0 18px 20px;
  }
}

@media (min-width: 880px) {
  .page-about .ab-split {
    grid-template-columns: minmax(0, 0.68fr) minmax(0, 1.32fr);
    gap: clamp(34px, 5vw, 84px);
  }

  .page-about .ab-split__head {
    position: sticky;
    top: calc(var(--header-h) + 28px);
    align-self: start;
  }

  .page-about .ab-cover__grid {
    grid-template-columns: minmax(0, 0.78fr) minmax(0, 1.22fr);
    gap: clamp(34px, 5vw, 76px);
    align-items: start;
  }

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

  .page-about .ab-cta__inner {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 0.9fr);
    align-items: center;
  }
}

@media (min-width: 900px) {
  .page-about .ab-hero__grid {
    grid-template-columns: minmax(0, 1.55fr) minmax(280px, 0.85fr);
    align-items: end;
    gap: clamp(34px, 5vw, 76px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-chips li,
  .page-about .ab-role,
  .page-about .ab-role__chev,
  .page-about .ab-tl__dot {
    transition: none;
  }

  .page-about .ab-tl__scroller {
    scroll-snap-type: none;
  }
}