.page-about {
  --ab-ink: rgba(233, 237, 246, 0.82);
  --ab-ink-dim: rgba(233, 237, 246, 0.58);
  --ab-hair: rgba(154, 166, 190, 0.26);
  --ab-hair-strong: rgba(154, 166, 190, 0.46);
}

.page-about .ab-wrap {
  display: grid;
  gap: 44px;
  padding-block: 18px 72px;
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  display: grid;
  gap: 26px;
}

.page-about .ab-hero__lede {
  display: grid;
  gap: 14px;
}

.page-about .ab-kicker {
  margin: 0;
  font-family: var(--bm-font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--bm-lime);
}

.page-about .ab-hero h1 {
  margin: 0;
  font-family: var(--bm-font-title);
  font-weight: 900;
  font-size: clamp(34px, 9.4vw, 70px);
  line-height: 0.98;
  letter-spacing: -0.012em;
  color: var(--bm-paper);
  max-width: 14em;
}

.page-about .ab-hero__text {
  margin: 0;
  max-width: 36em;
  font-size: 16px;
  line-height: 1.9;
  color: var(--ab-ink);
}

.page-about .ab-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 4px;
}

.page-about .ab-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--ab-hair);
  border: 1px solid var(--ab-hair);
}

.page-about .ab-stat {
  background: var(--bm-panel);
  padding: 14px 14px 16px;
  display: grid;
  gap: 4px;
  align-content: start;
}

.page-about .ab-stat .bm-metric__value {
  font-size: clamp(26px, 7vw, 40px);
  color: var(--bm-lime);
  line-height: 1;
}

.page-about .ab-stat .bm-metric__label {
  font-size: 13px;
  color: var(--bm-paper);
}

.page-about .ab-stat .bm-metric__note {
  font-size: 12px;
  line-height: 1.6;
  color: var(--ab-ink-dim);
}

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

.page-about .ab-hero__fig img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  display: block;
  border: 1px solid var(--ab-hair);
}

/* ---------- 章节通用 ---------- */
.page-about .bm-section__note {
  max-width: 42em;
  color: var(--ab-ink);
  line-height: 1.9;
}

/* ---------- 时间轴 ---------- */
.page-about .ab-timeline {
  display: grid;
  gap: 26px;
  margin-top: 26px;
}

.page-about .ab-timeline__list {
  list-style: none;
  margin: 0;
  padding: 0 0 0 24px;
  position: relative;
  display: grid;
  gap: 16px;
}

.page-about .ab-timeline__list::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(
    180deg,
    var(--bm-lime) 0%,
    rgba(200, 255, 77, 0.55) 22%,
    var(--ab-hair-strong) 62%,
    rgba(154, 166, 190, 0.14) 100%
  );
}

.page-about .ab-node {
  position: relative;
}

.page-about .ab-node::before {
  content: "";
  position: absolute;
  left: -23px;
  top: 15px;
  width: 11px;
  height: 11px;
  background: var(--bm-lime);
  box-shadow: 0 0 0 3px rgba(200, 255, 77, 0.14);
}

.page-about .ab-node__btn {
  width: 100%;
  display: grid;
  grid-template-columns: auto 1fr;
  grid-template-areas:
    "idx year"
    "label label";
  gap: 6px 12px;
  align-items: baseline;
  text-align: left;
  padding: 13px 15px;
  background: var(--bm-panel);
  border: 1px solid var(--ab-hair);
  color: var(--bm-paper);
  font: inherit;
  cursor: pointer;
  transition: border-color 0.16s ease, background-color 0.16s ease;
}

.page-about .ab-node__btn:hover,
.page-about .ab-node__btn:focus-visible {
  border-color: var(--bm-lime);
  background: var(--bm-raised);
}

.page-about .ab-node__btn:focus-visible {
  outline: 1px solid var(--bm-blue);
  outline-offset: 2px;
}

.page-about .ab-node__idx {
  grid-area: idx;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--bm-orange);
}

.page-about .ab-node__year {
  grid-area: year;
  font-size: 13px;
  color: var(--ab-ink-dim);
}

.page-about .ab-node__label {
  grid-area: label;
  font-family: var(--bm-font-title);
  font-weight: 800;
  font-size: clamp(19px, 5vw, 26px);
  line-height: 1.2;
  letter-spacing: 0.01em;
}

.page-about .ab-node__panel {
  border: 1px solid var(--ab-hair);
  border-top: 0;
  background: rgba(19, 28, 58, 0.62);
  padding: 14px 15px 16px;
  color: var(--ab-ink);
  font-size: 14px;
  line-height: 1.9;
  overflow: hidden;
  transition: max-height 0.24s ease, opacity 0.2s ease, padding 0.24s ease;
}

.page-about .ab-node__panel p {
  margin: 0 0 8px;
  max-width: 38em;
}

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

.page-about .ab-node__btn[aria-expanded="true"] + .ab-node__panel {
  max-height: 26rem;
  opacity: 1;
}

.page-about .ab-node__btn[aria-expanded="false"] + .ab-node__panel {
  max-height: 0;
  opacity: 0;
  padding-top: 0;
  padding-bottom: 0;
  border-color: transparent;
}

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

.page-about .ab-timeline__media img {
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  display: block;
  border: 1px solid var(--ab-hair);
}

/* ---------- 流程 ---------- */
.page-about .ab-flow {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--ab-hair);
  border: 1px solid var(--ab-hair);
}

.page-about .ab-flow__step {
  background: var(--bm-base);
  padding: 18px 16px 20px;
  display: grid;
  gap: 8px;
  position: relative;
}

.page-about .ab-flow__step::after {
  content: "";
  position: absolute;
  left: 16px;
  right: 16px;
  top: 0;
  height: 1px;
  background: transparent;
}

.page-about .ab-flow__no {
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--bm-orange);
}

.page-about .ab-flow__title {
  margin: 0;
  font-family: var(--bm-font-title);
  font-weight: 800;
  font-size: 20px;
  line-height: 1.25;
  color: var(--bm-paper);
}

.page-about .ab-flow__step p {
  margin: 0;
  font-size: 14px;
  line-height: 1.88;
  color: var(--ab-ink);
  max-width: 36em;
}

/* ---------- 团队堆叠条 ---------- */
.page-about .ab-stack {
  margin-top: 26px;
  display: grid;
  gap: 12px;
}

.page-about .ab-stack__row {
  border: 1px solid var(--ab-hair);
  background: var(--bm-panel);
  padding: 14px 16px 16px;
  display: grid;
  gap: 10px;
  transition: border-color 0.16s ease, background-color 0.16s ease;
}

.page-about .ab-stack__row:hover {
  border-color: var(--ab-hair-strong);
  background: var(--bm-raised);
}

.page-about .ab-stack__row:hover .ab-stack__duty {
  color: var(--bm-paper);
}

.page-about .ab-stack__top {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
}

.page-about .ab-stack__name {
  font-family: var(--bm-font-title);
  font-weight: 800;
  font-size: 19px;
  color: var(--bm-paper);
}

.page-about .ab-stack__num {
  font-size: 14px;
  color: var(--bm-lime);
}

.page-about .ab-stack__bar {
  height: 6px;
  background: rgba(154, 166, 190, 0.16);
  overflow: hidden;
}

.page-about .ab-stack__fill {
  display: block;
  height: 100%;
}

.page-about .ab-fill--a {
  width: 29%;
  background: linear-gradient(90deg, var(--bm-lime), rgba(200, 255, 77, 0.3));
}

.page-about .ab-fill--b {
  width: 32%;
  background: linear-gradient(90deg, var(--bm-orange), rgba(255, 106, 43, 0.28));
}

.page-about .ab-fill--c {
  width: 21%;
  background: linear-gradient(90deg, #9AA6BE, rgba(154, 166, 190, 0.28));
}

.page-about .ab-fill--d {
  width: 18%;
  background: linear-gradient(90deg, #3F7DFF, rgba(63, 125, 255, 0.28));
}

.page-about .ab-stack__duty {
  margin: 0;
  font-size: 13px;
  line-height: 1.85;
  color: var(--ab-ink-dim);
  transition: color 0.16s ease;
}

/* ---------- 合作方 ---------- */
.page-about .ab-partners {
  margin-top: 26px;
  display: grid;
  gap: 20px;
}

.page-about .ab-partners__grid {
  display: grid;
  gap: 1px;
  background: var(--ab-hair);
  border: 1px solid var(--ab-hair);
}

.page-about .ab-partner {
  background: var(--bm-base);
  padding: 18px 16px 20px;
  display: grid;
  gap: 10px;
  align-content: start;
}

.page-about .ab-partner__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border: 1px solid var(--ab-hair-strong);
  color: var(--bm-lime);
}

.page-about .ab-partner__name {
  margin: 0;
  font-family: var(--bm-font-title);
  font-weight: 800;
  font-size: 19px;
  line-height: 1.3;
  color: var(--bm-paper);
}

.page-about .ab-partner p {
  margin: 0;
  font-size: 14px;
  line-height: 1.88;
  color: var(--ab-ink);
  max-width: 34em;
}

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

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

/* ---------- 专栏 ---------- */
.page-about .ab-columns {
  margin-top: 26px;
  display: grid;
  gap: 12px;
}

.page-about .ab-column {
  background: var(--bm-panel);
  border: 1px solid var(--ab-hair);
  padding: 18px 16px 20px;
  display: grid;
  gap: 10px;
  align-content: start;
  border-left: 2px solid var(--bm-lime);
}

.page-about .ab-column:nth-child(2) {
  border-left-color: var(--bm-silver);
}

.page-about .ab-column:nth-child(3) {
  border-left-color: var(--bm-orange);
}

.page-about .ab-column h3 {
  margin: 0;
  font-family: var(--bm-font-title);
  font-weight: 800;
  font-size: 20px;
  line-height: 1.25;
  color: var(--bm-paper);
}

.page-about .ab-column p {
  margin: 0;
  font-size: 14px;
  line-height: 1.88;
  color: var(--ab-ink);
  max-width: 32em;
}

.page-about .ab-columns__more {
  margin: 18px 0 0;
  font-size: 14px;
  line-height: 1.9;
  color: var(--ab-ink-dim);
}

.page-about .ab-link {
  color: var(--bm-blue);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .ab-link:hover,
.page-about .ab-link:focus-visible {
  color: var(--bm-lime);
}

.page-about .ab-link:focus-visible {
  outline: 1px solid var(--bm-blue);
  outline-offset: 2px;
}

/* ---------- 使用人群 ---------- */
.page-about .ab-audience {
  margin-top: 26px;
  display: grid;
  gap: 22px;
}

.page-about .ab-audience__figures {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--ab-hair);
  border: 1px solid var(--ab-hair);
}

.page-about .ab-figure {
  background: var(--bm-panel);
  padding: 18px 16px;
  display: grid;
  gap: 6px;
  align-content: start;
}

.page-about .ab-figure .bm-metric__value {
  line-height: 1;
  color: var(--bm-lime);
}

.page-about .ab-figure .bm-metric__label {
  font-size: 13px;
  color: var(--ab-ink-dim);
}

.page-about .ab-scenes {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .ab-scene {
  padding-left: 16px;
  border-left: 1px solid var(--ab-hair-strong);
  display: grid;
  gap: 5px;
}

.page-about .ab-scene h3 {
  margin: 0;
  font-family: var(--bm-font-title);
  font-weight: 800;
  font-size: 18px;
  color: var(--bm-paper);
}

.page-about .ab-scene p {
  margin: 0;
  font-size: 14px;
  line-height: 1.88;
  color: var(--ab-ink);
  max-width: 34em;
}

/* ---------- 运营主体（浅色呼吸段） ---------- */
.page-about .ab-entity {
  margin-top: 26px;
  color: #131C3A;
  border: 1px solid rgba(19, 28, 58, 0.12);
  padding: 22px 18px 26px;
}

.page-about .ab-entity__grid {
  display: grid;
  gap: 22px;
}

.page-about .ab-entity__block {
  display: grid;
  gap: 8px;
  align-content: start;
}

.page-about .ab-entity__title {
  margin: 0;
  font-family: var(--bm-font-title);
  font-weight: 800;
  font-size: 18px;
  color: #0A1024;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(19, 28, 58, 0.16);
}

.page-about .ab-entity__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: rgba(19, 28, 58, 0.82);
}

.page-about .ab-entity__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 9px;
}

.page-about .ab-entity__list li {
  display: grid;
  grid-template-columns: 5.4em 1fr;
  gap: 10px;
  font-size: 14px;
  line-height: 1.8;
  color: rgba(19, 28, 58, 0.82);
}

.page-about .ab-entity__k {
  color: rgba(19, 28, 58, 0.55);
}

.page-about .ab-entity .ab-link {
  color: #1B4BC4;
}

.page-about .ab-entity .ab-link:hover,
.page-about .ab-entity .ab-link:focus-visible {
  color: #B3153C;
}

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

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

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

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

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

@media (min-width: 720px) {
  .page-about .ab-node__btn {
    grid-template-columns: 46px 64px minmax(0, 1fr);
    grid-template-areas: "idx year label";
    align-items: center;
    gap: 0 14px;
    padding: 16px 18px;
  }

  .page-about .ab-node__panel {
    padding: 16px 18px 18px;
  }
}

@media (min-width: 960px) {
  .page-about .ab-wrap {
    gap: 60px;
    padding-block: 22px 96px;
  }

  .page-about .ab-hero {
    grid-template-columns: minmax(0, 1.4fr) minmax(280px, 0.6fr);
    align-items: end;
    column-gap: 32px;
    row-gap: 28px;
  }

  .page-about .ab-hero__fig {
    grid-column: 1 / -1;
  }

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

  .page-about .ab-timeline {
    grid-template-columns: minmax(0, 1fr) 320px;
    column-gap: 32px;
    align-items: start;
  }

  .page-about .ab-timeline__media {
    position: sticky;
    top: 72px;
  }

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

  .page-about .ab-partners {
    grid-template-columns: minmax(0, 1fr) 300px;
    column-gap: 28px;
    align-items: start;
  }

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

  .page-about .ab-audience {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.3fr);
    column-gap: 32px;
    align-items: start;
  }

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

  .page-about .ab-entity__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 28px;
  }

  .page-about .ab-entity {
    padding: 28px 26px 32px;
  }
}

@media (min-width: 1280px) {
  .page-about .ab-hero h1 {
    max-width: 12em;
  }

  .page-about .ab-timeline {
    grid-template-columns: minmax(0, 1fr) 360px;
  }
}
<<<END>>>