.page-about {
  --ab-gap: clamp(56px, 8vw, 112px);
  --ab-pad-top: clamp(28px, 5vw, 56px);
  color: var(--lk-paper);
  padding-bottom: clamp(32px, 5vw, 64px);
}

.page-about p {
  margin: 0 0 1em;
  color: rgba(242, 247, 244, 0.78);
  font-size: 16px;
  line-height: 1.85;
}

.page-about h2 {
  margin: 0 0 14px;
  font-family: var(--lk-font-display);
  font-weight: 800;
  font-size: clamp(25px, 4.4vw, 40px);
  line-height: 1.16;
  letter-spacing: -0.02em;
  color: var(--lk-paper);
}

.page-about h3 {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--lk-paper);
}

/* ---------- 面包屑 ---------- */
.page-about .lk-breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 18px;
  font-family: var(--lk-font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--lk-mist);
}

.page-about .lk-breadcrumb a {
  color: var(--lk-mist);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.25s var(--lk-ease), border-color 0.25s var(--lk-ease);
}

.page-about .lk-breadcrumb a:hover,
.page-about .lk-breadcrumb a:focus-visible {
  color: var(--lk-lime);
  border-bottom-color: var(--lk-lime);
  outline: none;
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  display: grid;
  gap: 30px;
  padding-top: var(--ab-pad-top);
  padding-bottom: var(--ab-gap);
}

.page-about .ab-hero__eyebrow {
  margin: 0 0 10px;
  font-family: var(--lk-font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--lk-lime);
}

.page-about .ab-hero__title {
  margin: 0 0 18px;
  font-family: var(--lk-font-display);
  font-weight: 900;
  font-size: clamp(33px, 7vw, 62px);
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--lk-paper);
}

.page-about .ab-hero__lead {
  margin: 0;
  max-width: 46ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.8;
  color: rgba(242, 247, 244, 0.8);
}

.page-about .ab-hero__meta {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px 18px;
  margin: 26px 0 0;
  padding: 20px 0 0;
  border-top: 1px solid var(--lk-line-soft);
}

.page-about .ab-hero__meta li {
  display: flex;
  flex-direction: column;
  gap: 4px;
  font-size: 12.5px;
  color: var(--lk-mist);
}

.page-about .ab-hero__meta .lk-mono {
  font-size: 20px;
  font-weight: 500;
  color: var(--lk-lime);
}

.page-about .ab-night {
  position: relative;
  min-height: 240px;
  aspect-ratio: 4 / 3;
  overflow: hidden;
  border: 1px solid var(--lk-line);
  clip-path: polygon(0 0, calc(100% - var(--lk-cut)) 0, 100% var(--lk-cut), 100% 100%, 0 100%);
  background:
    radial-gradient(120% 90% at 82% 0%, rgba(198, 255, 61, 0.18), transparent 55%),
    radial-gradient(90% 80% at 6% 100%, rgba(27, 77, 90, 0.8), transparent 62%),
    linear-gradient(158deg, var(--lk-deep), var(--lk-night) 62%);
}

.page-about .ab-night__svg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.page-about .ab-night__coord {
  position: absolute;
  font-family: var(--lk-font-mono);
  font-size: 10.5px;
  letter-spacing: 0.12em;
  color: rgba(228, 255, 158, 0.72);
}

.page-about .ab-night__coord--a { left: 16px; top: 16px; }
.page-about .ab-night__coord--b { right: 20px; bottom: 18px; color: rgba(242, 247, 244, 0.55); }
.page-about .ab-night__coord--c { left: 16px; bottom: 18px; color: rgba(255, 138, 61, 0.75); }

/* ---------- 章节轨道 + 长卷 ---------- */
.page-about .ab-rail {
  margin-bottom: 10px;
}

.page-about .ab-rail__list {
  list-style: none;
  margin: 0;
  padding: 10px 0;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.page-about .ab-rail__list::-webkit-scrollbar { display: none; }

.page-about .ab-rail__link {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 8px 13px;
  border: 1px solid var(--lk-line-soft);
  font-size: 12.5px;
  white-space: nowrap;
  text-decoration: none;
  color: var(--lk-mist);
  transition: color 0.25s var(--lk-ease), border-color 0.25s var(--lk-ease), background 0.25s var(--lk-ease);
}

.page-about .ab-rail__n {
  font-family: var(--lk-font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: rgba(198, 255, 61, 0.75);
}

.page-about .ab-rail__link:hover,
.page-about .ab-rail__link:focus-visible {
  color: var(--lk-paper);
  border-color: var(--lk-lime);
  outline: none;
}

.page-about .ab-chapters {
  min-width: 0;
}

.page-about .ab-ch {
  position: relative;
  padding: clamp(30px, 4.5vw, 52px) 0 var(--ab-gap);
  border-top: 1px solid var(--lk-line-soft);
  scroll-margin-top: calc(var(--lk-topbar-h) + 24px);
}

.page-about .ab-ch:first-child {
  border-top: 0;
  padding-top: 4px;
}

.page-about .ab-ch__head {
  margin-bottom: clamp(20px, 3vw, 34px);
}

.page-about .ab-ch__kicker {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0 0 12px;
  font-family: var(--lk-font-mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: var(--lk-mist);
}

.page-about .ab-ch__num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 32px;
  padding: 3px 0;
  background: linear-gradient(90deg, var(--lk-lime), rgba(198, 255, 61, 0.35));
  color: var(--lk-night);
  font-weight: 600;
  letter-spacing: 0.06em;
}

.page-about .ab-ch__kicker::after {
  content: "";
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--lk-line), transparent);
}

.page-about .ab-ch__intro {
  max-width: 56ch;
  margin: 0;
  font-size: 15px;
  color: rgba(242, 247, 244, 0.7);
}

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

/* 左右错位分栏 */
.page-about .ab-split {
  display: grid;
  gap: 24px;
  min-width: 0;
}

.page-about .ab-ch__media {
  margin: 0;
  min-width: 0;
}

.page-about .ab-ch__frame {
  overflow: hidden;
  border: 1px solid var(--lk-line);
  clip-path: polygon(0 0, calc(100% - var(--lk-cut)) 0, 100% var(--lk-cut), 100% 100%, 0 100%);
  background: var(--lk-deep);
}

.page-about .ab-ch__media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.72) contrast(1.05);
  transition: filter 0.45s var(--lk-ease);
}

.page-about .ab-ch__media:hover img { filter: saturate(0.88) brightness(1.07); }

.page-about .ab-ch__media figcaption {
  margin-top: 10px;
  font-family: var(--lk-font-mono);
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: var(--lk-mist);
}

.page-about .ab-quote {
  margin: 22px 0 0;
  padding: 16px 18px;
  border-left: 2px solid var(--lk-lime);
  background: linear-gradient(90deg, rgba(198, 255, 61, 0.1), transparent 72%);
  font-size: 16.5px;
  line-height: 1.7;
  color: var(--lk-paper);
}

/* ---------- 原则卡片 ---------- */
.page-about .ab-principles {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .ab-principle {
  position: relative;
  padding: 22px 20px 20px;
  border: 1px solid var(--lk-line);
  background: linear-gradient(180deg, var(--lk-lift), rgba(18, 59, 50, 0.5));
  clip-path: polygon(0 0, calc(100% - var(--lk-cut)) 0, 100% var(--lk-cut), 100% 100%, 0 100%);
  transition: transform 0.3s var(--lk-ease), border-color 0.3s var(--lk-ease), background 0.3s var(--lk-ease);
}

.page-about .ab-principle p { margin-bottom: 0.8em; font-size: 15px; }
.page-about .ab-principle p:last-child { margin-bottom: 0; }

.page-about .ab-principle:hover,
.page-about .ab-principle:focus-visible {
  transform: translateY(-2px);
  border-color: var(--lk-lime);
  outline: 2px solid rgba(198, 255, 61, 0.55);
  outline-offset: 2px;
}

.page-about .ab-principle__n {
  display: block;
  margin-bottom: 10px;
  font-family: var(--lk-font-mono);
  font-size: 13px;
  letter-spacing: 0.16em;
  color: var(--lk-lime);
}

.page-about .ab-principle__note {
  margin-top: 14px;
  padding-top: 10px;
  border-top: 1px dashed var(--lk-line-soft);
  font-family: var(--lk-font-mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--lk-mist);
}

/* ---------- 生产链路 ---------- */
.page-about .ab-chain {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
  min-width: 0;
}

.page-about .ab-chain__step {
  position: relative;
  padding: 16px 20px 16px 22px;
  border-left: 2px solid var(--lk-lime);
  background: linear-gradient(90deg, rgba(18, 59, 50, 0.92), rgba(18, 59, 50, 0.32));
  clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 14px, 100% 100%, 0 100%);
}

.page-about .ab-chain__step p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
}

.page-about .ab-chain__n {
  display: block;
  margin-bottom: 6px;
  font-family: var(--lk-font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: rgba(198, 255, 61, 0.8);
}

.page-about .ab-chain__step h3 { margin-bottom: 6px; font-size: 16px; }

/* ---------- 时间轴 ---------- */
.page-about .ab-tl {
  list-style: none;
  margin: 0;
  padding: 4px 0 0 22px;
  position: relative;
  min-width: 0;
}

.page-about .ab-tl::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, var(--lk-lime), rgba(198, 255, 61, 0.06));
}

.page-about .ab-tl__item {
  position: relative;
  padding-bottom: 22px;
}

.page-about .ab-tl__item:last-child { padding-bottom: 4px; }

.page-about .ab-tl__item::before {
  content: "";
  position: absolute;
  left: -21px;
  top: 7px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--lk-night);
  border: 1px solid var(--lk-lime);
  transition: background 0.25s var(--lk-ease);
}

.page-about .ab-tl__item:hover::before,
.page-about .ab-tl__item:focus::before,
.page-about .ab-tl__item:focus-within::before { background: var(--lk-lime); }

.page-about .ab-tl__year {
  display: block;
  font-family: var(--lk-font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--lk-lime);
}

.page-about .ab-tl__title {
  margin: 4px 0 0;
  font-size: 16px;
  font-weight: 600;
  color: var(--lk-paper);
}

.page-about .ab-tl__more {
  margin: 0;
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--lk-mist);
  transition: max-height 0.35s var(--lk-ease), opacity 0.3s var(--lk-ease), margin-top 0.3s var(--lk-ease);
}

.page-about .ab-tl__item:hover .ab-tl__more,
.page-about .ab-tl__item:focus .ab-tl__more,
.page-about .ab-tl__item:focus-within .ab-tl__more {
  max-height: 120px;
  opacity: 1;
  margin-top: 6px;
}

.page-about .ab-tl__item:focus { outline: none; }
.page-about .ab-tl__item:focus-visible { outline: 2px solid rgba(198, 255, 61, 0.5); outline-offset: 4px; }

/* ---------- 团队与协作 ---------- */
.page-about .ab-stats {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
}

.page-about .ab-stat {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 14px 12px;
  border: 1px solid var(--lk-line-soft);
  background: rgba(12, 43, 36, 0.66);
}

.page-about .ab-stat__num {
  font-family: var(--lk-font-mono);
  font-size: clamp(19px, 3.4vw, 27px);
  font-weight: 500;
  color: var(--lk-lime);
}

.page-about .ab-stat__label {
  font-size: 11.5px;
  line-height: 1.5;
  color: var(--lk-mist);
}

.page-about .ab-roles {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .ab-role {
  padding: 16px 18px;
  border-left: 1px solid var(--lk-line-soft);
  background: linear-gradient(90deg, rgba(18, 59, 50, 0.5), transparent 85%);
}

.page-about .ab-role h3 { font-size: 15.5px; margin-bottom: 6px; }
.page-about .ab-role p { margin: 0; font-size: 14px; line-height: 1.7; }

.page-about .ab-partner {
  padding: 22px 20px;
  border: 1px solid var(--lk-line);
  border-radius: 0;
  background:
    radial-gradient(110% 120% at 100% 0%, rgba(27, 77, 90, 0.55), transparent 60%),
    linear-gradient(180deg, rgba(18, 59, 50, 0.85), rgba(6, 26, 22, 0.9));
  clip-path: polygon(0 0, calc(100% - var(--lk-cut)) 0, 100% var(--lk-cut), 100% 100%, 0 100%);
}

.page-about .ab-partner__title {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin: 0 0 12px;
  font-size: 17px;
  font-weight: 600;
  color: var(--lk-paper);
}

.page-about .ab-partner__title .lk-mono {
  font-size: 24px;
  color: var(--lk-orange);
}

.page-about .ab-partner p { font-size: 14.5px; }
.page-about .ab-partner p:last-child { margin-bottom: 0; }

.page-about .ab-inline-link {
  color: var(--lk-lime);
  text-decoration: none;
  border-bottom: 1px solid rgba(198, 255, 61, 0.5);
  transition: border-color 0.25s var(--lk-ease);
}

.page-about .ab-inline-link:hover,
.page-about .ab-inline-link:focus-visible {
  border-bottom-color: var(--lk-lime);
  outline: 2px solid rgba(198, 255, 61, 0.45);
  outline-offset: 2px;
}

/* ---------- 视觉语言 ---------- */
.page-about .ab-swatches {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.page-about .ab-swatch {
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 0;
}

.page-about .ab-swatch__chip {
  display: block;
  height: 58px;
  border: 1px solid var(--lk-line-soft);
  clip-path: polygon(0 0, calc(100% - var(--lk-cut-s)) 0, 100% var(--lk-cut-s), 100% 100%, 0 100%);
}

.page-about .ab-swatch--night .ab-swatch__chip { background: var(--lk-night); }
.page-about .ab-swatch--deep .ab-swatch__chip { background: var(--lk-deep); }
.page-about .ab-swatch--lime .ab-swatch__chip { background: var(--lk-lime); }
.page-about .ab-swatch--orange .ab-swatch__chip { background: var(--lk-orange); }

.page-about .ab-swatch__name {
  margin-top: 6px;
  font-size: 14px;
  color: var(--lk-paper);
}

.page-about .ab-swatch__hex {
  font-family: var(--lk-font-mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--lk-lime);
}

.page-about .ab-swatch__use {
  font-size: 12px;
  line-height: 1.6;
  color: var(--lk-mist);
}

.page-about .ab-visual-notes {
  padding: 18px 20px;
  border-left: 2px solid var(--lk-blue);
  background: linear-gradient(90deg, rgba(27, 77, 90, 0.4), transparent 80%);
}

.page-about .ab-visual-notes p { margin: 0; font-size: 14.5px; }

/* ---------- 下一步 ---------- */
.page-about .ab-next {
  margin-top: clamp(28px, 4vw, 48px);
  padding: clamp(22px, 4vw, 40px);
  border: 1px solid var(--lk-line);
  background:
    radial-gradient(100% 120% at 92% 0%, rgba(198, 255, 61, 0.18), transparent 58%),
    linear-gradient(150deg, rgba(27, 77, 90, 0.55), rgba(6, 26, 22, 0.95));
  clip-path: polygon(0 0, calc(100% - var(--lk-cut)) 0, 100% var(--lk-cut), 100% 100%, 0 100%);
}

.page-about .ab-next .lk-eyebrow {
  margin: 0 0 10px;
  font-family: var(--lk-font-mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: var(--lk-lime);
}

.page-about .ab-next h2 {
  margin-bottom: 20px;
  max-width: 24ch;
}

.page-about .ab-next__links {
  display: grid;
  gap: 10px;
}

.page-about .ab-next__link {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 14px 16px;
  border: 1px solid var(--lk-line-soft);
  text-decoration: none;
  transition: transform 0.28s var(--lk-ease), border-color 0.28s var(--lk-ease), background 0.28s var(--lk-ease);
}

.page-about .ab-next__link:hover,
.page-about .ab-next__link:focus-visible {
  transform: translateY(-2px);
  border-color: var(--lk-lime);
  background: rgba(198, 255, 61, 0.06);
  outline: 2px solid rgba(198, 255, 61, 0.5);
  outline-offset: 2px;
}

.page-about .ab-next__link-t {
  font-size: 15.5px;
  font-weight: 600;
  color: var(--lk-paper);
}

.page-about .ab-next__link-d {
  font-size: 13px;
  line-height: 1.6;
  color: var(--lk-mist);
}

.page-about .ab-next__link--accent {
  border-color: rgba(255, 138, 61, 0.5);
  background: rgba(255, 138, 61, 0.08);
}

.page-about .ab-next__link--accent .ab-next__link-t { color: var(--lk-orange); }

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .ab-hero__meta { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .page-about .ab-roles { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .page-about .ab-swatches { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .page-about .ab-next__links { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 860px) {
  .page-about .ab-hero {
    grid-template-columns: 5fr 6fr;
    align-items: center;
    gap: clamp(28px, 4vw, 56px);
  }

  .page-about .ab-split--img-right,
  .page-about .ab-split--img-left {
    grid-template-columns: 1.05fr 0.95fr;
    align-items: start;
    gap: clamp(24px, 3.4vw, 48px);
  }

  .page-about .ab-split--img-left { grid-template-columns: 0.95fr 1.05fr; }

  .page-about .ab-principles { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
}

@media (min-width: 1024px) {
  .page-about .ab-flow {
    display: grid;
    grid-template-columns: 180px minmax(0, 1fr);
    gap: clamp(28px, 3.6vw, 56px);
    align-items: start;
  }

  .page-about .ab-rail {
    position: sticky;
    top: calc(var(--lk-topbar-h) + 28px);
    margin: 0;
  }

  .page-about .ab-rail__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding: 4px 0;
    border-left: 1px solid var(--lk-line-soft);
  }

  .page-about .ab-rail__link {
    border: 0;
    border-left: 2px solid transparent;
    margin-left: -1px;
    padding: 10px 12px;
    font-size: 13px;
    white-space: normal;
  }

  .page-about .ab-rail__link:hover,
  .page-about .ab-rail__link:focus-visible {
    background: rgba(198, 255, 61, 0.06);
    border-left-color: var(--lk-lime);
  }

  .page-about .ab-ch { padding-top: clamp(36px, 3.4vw, 56px); }
  .page-about .ab-tl__more { max-height: 0; }
  .page-about .ab-tl__item { padding-bottom: 26px; }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-ch__media img,
  .page-about .ab-principle,
  .page-about .ab-tl__more,
  .page-about .ab-next__link,
  .page-about .ab-tl__item::before {
    transition: none;
  }

  .page-about .ab-principle:hover,
  .page-about .ab-principle:focus-visible,
  .page-about .ab-next__link:hover,
  .page-about .ab-next__link:focus-visible {
    transform: none;
  }
}