.page-about {
  --ab-line-x: 16px;
}

.page-about .ab-crumb__sep {
  margin: 0 8px;
  opacity: 0.45;
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  position: relative;
  padding: clamp(26px, 5vw, 60px) 0 clamp(36px, 6vw, 76px);
  border-bottom: 1px solid var(--lk-line);
  overflow: hidden;
}

.page-about .ab-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(118deg, rgba(53, 240, 198, 0.1), transparent 46%),
    linear-gradient(300deg, rgba(233, 180, 76, 0.07), transparent 40%);
  pointer-events: none;
}

.page-about .ab-hero__grid {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(26px, 5vw, 52px);
}

.page-about .ab-hero__lead .lk-h1 {
  color: var(--lk-paper);
  letter-spacing: -0.01em;
}

.page-about .ab-hero__lede {
  margin: 20px 0 0;
  max-width: 60ch;
  color: var(--lk-fg);
  font-size: 14.5px;
  line-height: 1.85;
}

.page-about .ab-hero__acts {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .ab-hero__board {
  position: relative;
  padding: 20px 22px 10px;
  border: 1px solid var(--lk-line-strong);
  background: linear-gradient(158deg, var(--lk-ink-2), var(--lk-ink));
  box-shadow: 0 1px 0 rgba(53, 240, 198, 0.3), 0 16px 34px -26px #000;
  transform: rotate(-1.2deg);
}

.page-about .ab-hero__boardtitle {
  margin: 0 0 6px;
  font-family: var(--lk-mono);
  font-size: 11px;
  letter-spacing: 0.32em;
  color: var(--lk-gold);
}

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

.page-about .ab-board > div {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding: 10px 0;
  border-bottom: 1px dashed var(--lk-line);
}

.page-about .ab-board > div:last-child {
  border-bottom: 0;
}

.page-about .ab-board dt {
  color: var(--lk-haze);
  font-size: 12.5px;
  line-height: 1.5;
}

.page-about .ab-board dd {
  margin: 0;
  font-family: var(--lk-mono);
  font-size: 19px;
  letter-spacing: 0.04em;
  color: var(--lk-cyan);
  white-space: nowrap;
}

/* ---------- 正文骨架 ---------- */
.page-about .ab-body {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(26px, 4vw, 48px);
  padding: clamp(36px, 6vw, 80px) 0 clamp(48px, 7vw, 96px);
}

.page-about .ab-index {
  border-left: 1px solid var(--lk-line);
}

.page-about .lk-index__title {
  margin: 0 0 12px;
  font-family: var(--lk-mono);
  font-size: 11px;
  letter-spacing: 0.3em;
  color: var(--lk-gold);
}

.page-about .lk-index__list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .lk-index__list a {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 7px 0;
  color: var(--lk-fg);
  font-size: 13.5px;
  line-height: 1.5;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.18s ease, border-color 0.18s ease;
}

.page-about .lk-index__list a:hover,
.page-about .lk-index__list a[aria-current="true"] {
  color: var(--lk-cyan);
  border-bottom-color: var(--lk-cyan-line);
}

.page-about .ab-index__n {
  font-family: var(--lk-mono);
  font-size: 11px;
  color: var(--lk-haze);
  letter-spacing: 0.08em;
}

.page-about .lk-index__list a[aria-current="true"] .ab-index__n {
  color: var(--lk-gold);
}

.page-about .ab-flow {
  position: relative;
  min-width: 0;
}

/* ---------- 章节 ---------- */
.page-about .ab-chapter {
  position: relative;
  padding-bottom: clamp(34px, 5vw, 66px);
  margin-bottom: clamp(34px, 5vw, 66px);
  border-bottom: 1px solid var(--lk-line);
  scroll-margin-top: calc(var(--lk-anchor) + 20px);
}

.page-about .ab-chapter:last-child {
  padding-bottom: 0;
  margin-bottom: 0;
  border-bottom: 0;
}

.page-about .ab-chapter .lk-h2 {
  color: var(--lk-paper);
}

.page-about .ab-chapter__no {
  display: block;
  margin-bottom: 8px;
  font-family: var(--lk-mono);
  font-size: 11px;
  letter-spacing: 0.34em;
  color: var(--lk-gold);
}

.page-about .ab-chapter__year {
  display: block;
  margin-bottom: -0.1em;
  font-family: var(--lk-mono);
  font-size: clamp(56px, 15vw, 132px);
  line-height: 0.88;
  letter-spacing: -0.04em;
  color: rgba(53, 240, 198, 0.1);
  -webkit-text-stroke: 1px rgba(53, 240, 198, 0.45);
  user-select: none;
}

.page-about .ab-prose {
  margin-top: 14px;
  max-width: 68ch;
}

.page-about .ab-prose p {
  margin: 0 0 14px;
  color: var(--lk-fg);
  font-size: 14.5px;
  line-height: 1.85;
}

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

/* ---------- 团队拓扑 SVG ---------- */
.page-about .ab-map {
  display: block;
  width: 100%;
  max-width: 640px;
  height: auto;
  margin: 26px 0 4px;
}

.page-about .ab-map__link path {
  fill: none;
  stroke: var(--lk-cyan);
  stroke-width: 1;
  stroke-dasharray: 4 4;
  opacity: 0.65;
}

.page-about .ab-map__node rect {
  fill: var(--lk-ink-2);
  stroke: var(--lk-line-strong);
  stroke-width: 1;
}

.page-about .ab-map__txt text {
  fill: var(--lk-paper);
  font-family: var(--lk-head);
  font-size: 13px;
  font-weight: 700;
}

.page-about .ab-map__txt .ab-map__sub {
  fill: var(--lk-haze);
  font-size: 10.5px;
  font-weight: 400;
}

.page-about .ab-map__txt .ab-map__big {
  fill: var(--lk-cyan);
  font-family: var(--lk-mono);
  font-size: 19px;
  letter-spacing: 0.06em;
}

/* ---------- 图文错位分栏 ---------- */
.page-about .ab-chapter--split {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(20px, 4vw, 40px);
}

.page-about .ab-figure {
  margin: 0;
  border: 1px solid var(--lk-line-strong);
  background: var(--lk-ink-2);
  padding: 10px;
}

.page-about .ab-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.92) contrast(1.05);
}

.page-about .ab-figure figcaption {
  margin-top: 10px;
  padding-top: 8px;
  border-top: 1px solid var(--lk-line);
  font-size: 12px;
  line-height: 1.6;
  color: var(--lk-haze);
}

.page-about .ab-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-linkline {
  margin: 18px 0 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--lk-fg);
}

.page-about .ab-linkline a {
  color: var(--lk-cyan);
  text-decoration: none;
  border-bottom: 1px solid var(--lk-cyan-line);
}

.page-about .ab-linkline a:hover {
  color: var(--lk-cyan-soft);
}

/* ---------- 节奏表（暖纸色分区） ---------- */
.page-about .ab-chapter--paper {
  padding: clamp(26px, 5vw, 52px);
  border: 1px solid var(--lk-paper-dim);
  border-bottom: 1px solid var(--lk-paper-dim);
  background: var(--lk-paper);
  color: var(--lk-text-ink);
}

.page-about .ab-chapter--paper .lk-h2 {
  color: var(--lk-text-ink);
}

.page-about .ab-chapter--paper .ab-chapter__no {
  color: #8a6a1f;
}

.page-about .ab-cadence__lede {
  margin: 12px 0 0;
  max-width: 62ch;
  font-size: 14.5px;
  line-height: 1.8;
  color: #3d4a44;
}

.page-about .ab-banner {
  margin: 26px 0 0;
  border: 1px solid var(--lk-paper-dim);
  overflow: hidden;
}

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

.page-about .ab-timeline {
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--lk-paper-dim);
}

.page-about .ab-timeline__item {
  padding: 18px 0;
  border-bottom: 1px solid var(--lk-paper-dim);
}

.page-about .ab-timeline__key {
  display: inline-block;
  margin-bottom: 6px;
  padding: 3px 9px;
  border: 1px solid #d8c9a8;
  font-family: var(--lk-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: #7a5f18;
  background: rgba(233, 180, 76, 0.14);
}

.page-about .ab-timeline__item .lk-h3 {
  margin: 0 0 8px;
  color: var(--lk-text-ink);
  font-size: 16px;
  line-height: 1.5;
}

.page-about .ab-timeline__item p {
  margin: 0;
  max-width: 66ch;
  font-size: 13.5px;
  line-height: 1.8;
  color: #3d4a44;
}

.page-about .ab-cadence__foot {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.page-about .ab-chapter--paper .lk-btn--ghost {
  border-color: rgba(22, 36, 31, 0.4);
  color: var(--lk-text-ink);
}

/* ---------- 桌面布局 ---------- */
@media (min-width: 860px) {
  .page-about .ab-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: start;
  }

  .page-about .ab-hero__board {
    margin-top: 6px;
  }

  .page-about .ab-chapter--split {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: start;
  }

  .page-about .ab-chapter--rev {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  }

  .page-about .ab-figure {
    transform: rotate(1.1deg);
  }

  .page-about .ab-chapter--rev .ab-figure {
    transform: rotate(-1.3deg);
  }

  .page-about .ab-timeline__item {
    display: grid;
    grid-template-columns: 160px minmax(0, 1fr);
    grid-template-areas:
      "key title"
      "key body";
    column-gap: 22px;
    row-gap: 6px;
    align-items: start;
  }

  .page-about .ab-timeline__key {
    grid-area: key;
    justify-self: start;
    margin-bottom: 0;
    margin-top: 2px;
  }

  .page-about .ab-timeline__item .lk-h3 {
    grid-area: title;
  }

  .page-about .ab-timeline__item p {
    grid-area: body;
  }
}

@media (min-width: 1000px) {
  .page-about .ab-body {
    grid-template-columns: 220px minmax(0, 1fr);
    gap: clamp(32px, 5vw, 64px);
    align-items: start;
  }

  .page-about .ab-index {
    position: sticky;
    top: calc(var(--lk-anchor) + 24px);
  }

  .page-about .ab-flow {
    padding-left: 44px;
  }

  .page-about .ab-flow::before {
    content: "";
    position: absolute;
    top: 10px;
    bottom: 48px;
    left: var(--ab-line-x);
    width: 1px;
    background: linear-gradient(180deg, var(--lk-cyan), rgba(53, 240, 198, 0.06));
    opacity: 0.55;
  }

  .page-about .ab-chapter__no {
    position: absolute;
    top: 4px;
    left: -24px;
    margin-bottom: 0;
    writing-mode: vertical-rl;
    letter-spacing: 0.34em;
  }

  .page-about .ab-chapter__year {
    font-size: clamp(72px, 9vw, 132px);
  }
}

/* ---------- 窄屏收口 ---------- */
@media (max-width: 999px) {
  .page-about .ab-index {
    border-left: 0;
    border-bottom: 1px solid var(--lk-line);
    padding-bottom: 12px;
  }

  .page-about .lk-index__list {
    display: flex;
    gap: 10px;
    overflow-x: auto;
    padding-bottom: 6px;
    -webkit-overflow-scrolling: touch;
  }

  .page-about .lk-index__list li {
    flex: 0 0 auto;
  }

  .page-about .lk-index__list a {
    padding: 6px 12px;
    border: 1px solid var(--lk-line);
    white-space: nowrap;
    font-size: 12.5px;
  }

  .page-about .lk-index__list a[aria-current="true"] {
    border-color: var(--lk-cyan-line);
    background: var(--lk-ink-2);
  }
}

@media (max-width: 560px) {
  .page-about .ab-hero__board {
    transform: none;
  }

  .page-about .ab-chapter__year {
    font-size: clamp(48px, 20vw, 76px);
  }

  .page-about .ab-chapter--paper {
    padding: 22px 18px;
  }

  .page-about .ab-map {
    margin-top: 20px;
  }
}