.page-about {
  background: var(--ink);
  color: var(--paper);
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  position: relative;
  padding: 30px 0 42px;
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(118% 88% at 92% -10%, rgba(255, 106, 26, 0.16), transparent 58%),
    linear-gradient(178deg, var(--turf) 0%, var(--ink) 74%);
}

.page-about .eyebrow {
  color: var(--orange);
  letter-spacing: 0.16em;
  margin: 20px 0 0;
}

.page-about .ab-hero h1 {
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: clamp(29px, 7.2vw, 58px);
  line-height: 1.14;
  letter-spacing: -0.015em;
  margin: 14px 0 0;
  max-width: 12em;
}

.page-about .ab-lede {
  margin: 22px 0 0;
  max-width: 60ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .ab-stats {
  list-style: none;
  margin: 32px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .ab-stat {
  position: relative;
  background: var(--glass);
  padding: 18px 14px 20px;
}

.page-about .ab-stat::before {
  content: "";
  position: absolute;
  left: 14px;
  top: 18px;
  width: 18px;
  height: 2px;
  background: var(--orange);
}

.page-about .ab-stat:nth-child(2)::before { background: var(--blue); }
.page-about .ab-stat:nth-child(3)::before { background: var(--yellow); }
.page-about .ab-stat:nth-child(4)::before { background: var(--mint); }

.page-about .ab-stat__num {
  display: block;
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: clamp(21px, 5vw, 30px);
  font-weight: 700;
  letter-spacing: -0.02em;
  font-variant-numeric: tabular-nums;
  color: var(--paper);
}

.page-about .ab-stat__k {
  display: block;
  margin-top: 6px;
  font-family: var(--font-cond);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--muted);
}

/* ---------- 区块骨架 ---------- */
.page-about .section {
  padding: 48px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .section:last-child {
  border-bottom: 0;
}

.page-about .section__head {
  margin-bottom: 28px;
}

.page-about .section__head .eyebrow {
  margin-top: 0;
}

.page-about .section h2 {
  font-family: var(--font-serif);
  font-weight: 800;
  font-size: clamp(22px, 4.8vw, 36px);
  line-height: 1.26;
  letter-spacing: -0.01em;
  margin: 10px 0 0;
}

.page-about .ab-head-gap {
  margin-top: 40px;
}

.page-about .ab-copy p {
  margin: 0 0 16px;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--muted);
  max-width: 58ch;
}

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

.page-about .ab-copy a {
  color: var(--blue);
  text-decoration: none;
  border-bottom: 1px solid rgba(31, 182, 255, 0.45);
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

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

/* ---------- 图文分栏 ---------- */
.page-about .ab-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
}

.page-about .ab-shot {
  margin: 0;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  background: var(--glass);
  overflow: hidden;
  box-shadow: 0 20px 40px -32px rgba(0, 0, 0, 0.95);
}

.page-about .ab-shot img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .ab-shot figcaption {
  padding: 10px 13px 12px;
  border-top: 1px solid var(--line);
  font-family: var(--font-cond);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  line-height: 1.65;
  color: var(--muted);
}

.page-about .ab-shot--band {
  border-color: var(--line);
}

/* ---------- 流程 ---------- */
.page-about .ab-flow {
  list-style: none;
  counter-reset: ab-step;
  margin: 0;
  padding: 0;
}

.page-about .ab-flow__step {
  counter-increment: ab-step;
  position: relative;
  padding: 16px 0 18px 46px;
  border-top: 1px solid var(--line);
}

.page-about .ab-flow__step:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .ab-flow__step::before {
  content: counter(ab-step, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 18px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--orange);
}

.page-about .ab-flow__t {
  margin: 0;
  font-family: var(--font-cond);
  font-size: 15.5px;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: var(--paper);
}

.page-about .ab-flow__d {
  margin: 7px 0 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--muted);
  max-width: 46ch;
}

/* ---------- 时间线 ---------- */
.page-about .ab-tl-section {
  background: linear-gradient(180deg, var(--ink) 0%, var(--turf) 52%, var(--ink) 100%);
}

.page-about .ab-spark {
  display: block;
  width: 200px;
  max-width: 100%;
  height: auto;
  margin: 16px 0 0;
  color: var(--orange);
  opacity: 0.75;
}

.page-about .ab-tl {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .ab-tl__item {
  position: relative;
  display: grid;
  grid-template-columns: 62px minmax(0, 1fr);
  column-gap: 24px;
  padding-bottom: 30px;
}

.page-about .ab-tl__item:last-child {
  padding-bottom: 0;
}

.page-about .ab-tl__item::before {
  content: "";
  position: absolute;
  top: 6px;
  bottom: 0;
  left: calc(62px + 12px);
  width: 1px;
  background: linear-gradient(180deg, var(--line-strong), rgba(159, 176, 166, 0.06));
}

.page-about .ab-tl__item:last-child::before {
  bottom: auto;
  height: 30px;
}

.page-about .ab-tl__year {
  position: relative;
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: clamp(19px, 4.4vw, 30px);
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--paper);
  transition: color 0.2s var(--ease);
}

.page-about .ab-tl__year::after {
  content: "";
  position: absolute;
  top: 7px;
  left: 100%;
  margin-left: 8px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--ink);
  border: 2px solid var(--muted);
  transition: border-color 0.2s var(--ease), background 0.2s var(--ease), transform 0.2s var(--ease);
}

.page-about .ab-tl__item:hover .ab-tl__year,
.page-about .ab-tl__item:focus-within .ab-tl__year {
  color: var(--orange);
}

.page-about .ab-tl__item:hover .ab-tl__year::after,
.page-about .ab-tl__item:focus-within .ab-tl__year::after {
  background: var(--orange);
  border-color: var(--orange);
  transform: scale(1.3);
}

.page-about .ab-tl__title {
  margin: 0;
  font-family: var(--font-serif);
  font-size: clamp(17px, 3.6vw, 22px);
  font-weight: 700;
  line-height: 1.36;
}

.page-about .ab-tl__text {
  margin: 9px 0 0;
  font-size: 14.8px;
  line-height: 1.82;
  color: var(--muted);
  max-width: 54ch;
}

.page-about .ab-tl__tags {
  margin: 12px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.page-about .ab-chip {
  display: inline-block;
  padding: 3px 8px;
  border: 1px solid var(--line-strong);
  border-radius: 2px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.08em;
  color: var(--muted);
  white-space: nowrap;
}

/* ---------- 团队 ---------- */
.page-about .ab-roles {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .ab-role {
  position: relative;
  background: var(--glass);
  padding: 22px 18px 26px;
  transition: background 0.2s var(--ease);
}

.page-about .ab-role::after {
  content: "";
  position: absolute;
  inset: 0;
  border-left: 2px solid transparent;
  pointer-events: none;
  transition: border-color 0.2s var(--ease);
}

.page-about .ab-role:hover {
  background: var(--turf);
}

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

.page-about .ab-role__count {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.1em;
  color: var(--orange);
  font-variant-numeric: tabular-nums;
}

.page-about .ab-role h3 {
  margin: 0;
  font-family: var(--font-serif);
  font-size: 18px;
  font-weight: 700;
  line-height: 1.32;
}

.page-about .ab-role__desc {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 合作 ---------- */
.page-about .ab-partners {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
}

.page-about .ab-partner {
  position: relative;
  padding: 20px 18px 22px;
  background: var(--glass);
  border: 1px solid var(--line);
  border-left-width: 3px;
  border-left-color: var(--blue);
  border-radius: var(--radius);
  transition: background 0.2s var(--ease);
}

.page-about .ab-partner:nth-child(2) { border-left-color: var(--mint); }
.page-about .ab-partner:nth-child(3) { border-left-color: var(--yellow); }
.page-about .ab-partner:nth-child(4) { border-left-color: var(--orange); }

.page-about .ab-partner:hover {
  background: var(--turf);
}

.page-about .ab-partner h3 {
  margin: 0;
  font-family: var(--font-serif);
  font-size: 18px;
  font-weight: 700;
  line-height: 1.32;
}

.page-about .ab-partner p {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 更正说明 ---------- */
.page-about .ab-note {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
  padding: 24px 20px 26px;
  border: 1px solid var(--line);
  border-top: 3px solid var(--orange);
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(255, 106, 26, 0.08), rgba(22, 33, 28, 0.92) 58%);
}

.page-about .ab-note .eyebrow {
  margin-top: 0;
}

/* ---------- 页尾导航 ---------- */
.page-about .ab-next {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .ab-next li {
  display: flex;
}

.page-about .ab-next__link {
  display: block;
  width: 100%;
  padding: 20px 18px 22px;
  background: var(--glass);
  color: var(--paper);
  text-decoration: none;
  transition: background 0.2s var(--ease), color 0.2s var(--ease);
}

.page-about .ab-next__link:hover,
.page-about .ab-next__link:focus-visible {
  background: var(--turf);
  color: var(--orange);
}

.page-about .ab-next__k {
  display: block;
  margin: 0 0 10px;
  font-family: var(--font-cond);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--muted);
}

.page-about .ab-next__t {
  display: block;
  font-family: var(--font-serif);
  font-size: 17px;
  font-weight: 700;
  line-height: 1.45;
}

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .ab-hero {
    padding: 44px 0 52px;
  }
  .page-about .ab-lede {
    font-size: 16.5px;
  }
}

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

@media (min-width: 760px) {
  .page-about .ab-partners {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
  }
  .page-about .ab-next {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 860px) {
  .page-about .section {
    padding: 68px 0;
  }
  .page-about .section__head {
    margin-bottom: 40px;
  }
  .page-about .ab-split {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
    gap: 48px;
    align-items: start;
  }
  .page-about .ab-split--wide-right {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.28fr);
  }
  .page-about .ab-tl__item {
    grid-template-columns: 132px minmax(0, 1fr);
    column-gap: 46px;
    padding-bottom: 44px;
  }
  .page-about .ab-tl__item::before {
    left: calc(132px + 23px);
  }
  .page-about .ab-tl__year::after {
    margin-left: 18px;
  }
  .page-about .ab-note {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
    gap: 36px;
    align-items: start;
    padding: 32px 30px 34px;
  }
  .page-about .ab-head-gap {
    margin-top: 56px;
  }
}

@media (min-width: 900px) {
  .page-about .ab-roles {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1060px) {
  .page-about .ab-roles {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .ab-next {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .ab-hero {
    padding: 56px 0 64px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-tl__year,
  .page-about .ab-tl__year::after,
  .page-about .ab-role,
  .page-about .ab-role::after,
  .page-about .ab-partner,
  .page-about .ab-next__link,
  .page-about .ab-copy a {
    transition: none;
  }
  .page-about .ab-tl__item:hover .ab-tl__year::after,
  .page-about .ab-tl__item:focus-within .ab-tl__year::after {
    transform: none;
  }
}