.page-about {
  --ab-line: var(--wl-hairline);
  background: var(--wl-ink);
  color: var(--wl-on-dark);
}

.page-about img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ---------- 首屏 ---------- */

.page-about .ab-hero {
  position: relative;
  overflow: hidden;
  padding: 92px 0 60px;
  background:
    radial-gradient(120% 90% at 84% 0%, rgba(201, 162, 39, 0.16), transparent 62%),
    linear-gradient(180deg, var(--wl-ink) 0%, var(--wl-ink) 70%, #0E2337 100%);
}

.page-about .ab-hero__frame {
  position: relative;
  margin: 0 16px;
  padding: 26px 18px 34px;
  border: 1px solid var(--ab-line);
  border-radius: var(--wl-radius);
  background: linear-gradient(180deg, rgba(18, 40, 63, 0.72), rgba(11, 26, 43, 0.34));
  box-shadow: var(--wl-shadow-2);
}

.page-about .ab-hero__frame::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 8px;
  background-image: repeating-linear-gradient(90deg, var(--wl-gold) 0 1px, transparent 1px 26px);
  opacity: 0.4;
  pointer-events: none;
}

.page-about .ab-hero__crumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 6px 0 22px;
  font-size: 13px;
  color: var(--wl-on-dark-dim);
}

.page-about .ab-hero__crumb a {
  color: var(--wl-gold-hi);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.24s var(--wl-ease);
}

.page-about .ab-hero__crumb a:hover {
  border-bottom-color: var(--wl-gold-hi);
}

.page-about .ab-hero__eyebrow {
  margin: 0 0 16px;
  font-family: var(--wl-font-mono);
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--wl-gold-hi);
}

.page-about .ab-hero__title {
  margin: 0 0 20px;
  font-family: var(--wl-font-display);
  font-size: clamp(28px, 6.6vw, 54px);
  line-height: 1.16;
  letter-spacing: -0.02em;
  color: var(--wl-on-dark-strong);
  max-width: 18em;
}

.page-about .ab-hero__lead {
  margin: 0;
  max-width: 46em;
  font-size: 16.5px;
  line-height: 1.8;
  color: var(--wl-on-dark);
}

.page-about .ab-stats {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  border: 1px solid var(--ab-line);
  border-radius: var(--wl-radius);
  overflow: hidden;
  background: var(--ab-line);
}

.page-about .ab-stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px 14px;
  background: rgba(11, 26, 43, 0.78);
}

.page-about .ab-stat__num {
  font-family: var(--wl-font-mono);
  font-size: 22px;
  letter-spacing: 0.04em;
  color: var(--wl-gold-hi);
}

.page-about .ab-stat__label {
  font-size: 13px;
  color: var(--wl-on-dark-dim);
}

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

/* ---------- 通用章头 ---------- */

.page-about .ab-head {
  max-width: 44em;
  margin: 0 0 34px;
}

.page-about .ab-head__title {
  margin: 10px 0 14px;
  color: inherit;
}

.page-about .ab-head__lead {
  margin: 0;
  font-size: 16px;
  line-height: 1.8;
  color: inherit;
  opacity: 0.84;
}

/* ---------- 三类入口 ---------- */

.page-about .ab-work {
  background: linear-gradient(180deg, var(--wl-ink) 0%, var(--wl-ink-2) 58%, var(--wl-ink) 100%);
  color: var(--wl-on-dark);
}

.page-about .ab-work .ab-head__lead {
  color: var(--wl-on-dark);
  opacity: 0.82;
}

.page-about .ab-work__list {
  display: grid;
  gap: 1px;
  border: 1px solid var(--ab-line);
  border-radius: var(--wl-radius);
  overflow: hidden;
  background: var(--ab-line);
}

.page-about .ab-work__item {
  display: flex;
  flex-direction: column;
  padding: 24px 18px 26px;
  background: rgba(11, 26, 43, 0.66);
  transition: background 0.24s var(--wl-ease);
}

.page-about .ab-work__item:hover {
  background: rgba(18, 40, 63, 0.88);
}

.page-about .ab-work__top {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 14px;
}

.page-about .ab-work__num {
  font-family: var(--wl-font-mono);
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--wl-gold-hi);
}

.page-about .ab-work__item h3 {
  margin: 0 0 12px;
  color: var(--wl-on-dark-strong);
}

.page-about .ab-work__item > p {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--wl-on-dark);
}

.page-about .ab-work__note {
  margin: 16px 0 0;
  padding-left: 12px;
  border-left: 1px solid var(--ab-line);
  font-size: 14px;
  line-height: 1.7;
  color: var(--wl-on-dark-dim);
}

/* ---------- 版本时间线 ---------- */

.page-about .ab-timeline {
  background: var(--wl-paper);
  color: var(--wl-text);
}

.page-about .ab-timeline .ab-head__lead {
  color: var(--wl-text-soft);
  opacity: 1;
}

.page-about .ab-timeline__figure {
  margin: 0 0 44px;
}

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

.page-about .ab-tl::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 12px;
  bottom: 12px;
  width: 1px;
  background: linear-gradient(180deg, var(--wl-gold), rgba(201, 162, 39, 0.14));
}

.page-about .ab-tl__item {
  position: relative;
  padding: 0 0 34px 38px;
}

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

.page-about .ab-tl__tick {
  position: absolute;
  left: 0;
  top: 6px;
  width: 17px;
  height: 17px;
  border-radius: 50%;
  border: 1px solid var(--wl-gold);
  background: var(--wl-paper);
}

.page-about .ab-tl__item--current .ab-tl__tick {
  background: var(--wl-gold);
  box-shadow: 0 0 0 5px rgba(201, 162, 39, 0.18);
}

.page-about .ab-tl__meta {
  margin: 0 0 8px;
  font-family: var(--wl-font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--wl-text-soft);
}

.page-about .ab-tl__item h3 {
  margin: 0 0 10px;
  color: var(--wl-text);
}

.page-about .ab-tl__item > p {
  margin: 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--wl-text-soft);
  max-width: 44em;
}

.page-about .ab-tl__more {
  margin-top: 12px;
  max-width: 44em;
}

.page-about .ab-tl__more summary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding-bottom: 2px;
  cursor: pointer;
  list-style: none;
  font-family: var(--wl-font-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--wl-text);
  border-bottom: 1px solid var(--wl-gold);
}

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

.page-about .ab-tl__more summary::before {
  content: "+";
  color: var(--wl-gold);
  font-size: 14px;
}

.page-about .ab-tl__more[open] summary::before {
  content: "–";
}

.page-about .ab-tl__more p {
  margin: 12px 0 0;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--wl-text-soft);
}

/* ---------- 团队 ---------- */

.page-about .ab-team {
  background: linear-gradient(180deg, var(--wl-paper) 0%, #EFE9DD 100%);
  color: var(--wl-text);
}

.page-about .ab-team__grid {
  display: grid;
  gap: 34px;
}

.page-about .ab-team__text .ab-head__title {
  margin: 10px 0 18px;
}

.page-about .ab-team__text > p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--wl-text-soft);
  max-width: 44em;
}

.page-about .ab-bar {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  display: grid;
  gap: 16px;
  max-width: 44em;
}

.page-about .ab-bar__item {
  display: block;
}

.page-about .ab-bar__item--a {
  --w: 39%;
}

.page-about .ab-bar__item--b {
  --w: 61%;
}

.page-about .ab-bar__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  font-size: 14px;
  color: var(--wl-text-soft);
}

.page-about .ab-bar__count {
  font-family: var(--wl-font-mono);
  font-size: 13px;
  color: var(--wl-text);
}

.page-about .ab-bar__track {
  display: block;
  margin-top: 8px;
  height: 8px;
  border-radius: 999px;
  background: rgba(28, 37, 48, 0.12);
  overflow: hidden;
}

.page-about .ab-bar__fill {
  display: block;
  width: var(--w, 0%);
  height: 100%;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--wl-gold), var(--wl-gold-hi));
  transition: filter 0.24s var(--wl-ease);
}

.page-about .ab-bar__item:hover .ab-bar__fill {
  filter: brightness(1.1);
}

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

/* ---------- 覆盖范围 ---------- */

.page-about .ab-coverage {
  background: #EFE9DD;
  color: var(--wl-text);
}

.page-about .ab-coverage .ab-head__lead {
  color: var(--wl-text-soft);
  opacity: 1;
}

.page-about .ab-coverage__body {
  display: grid;
  gap: 26px;
  margin-bottom: 40px;
}

.page-about .ab-map {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 8px;
  padding: 16px;
  border: 1px solid var(--ab-line);
  border-radius: var(--wl-radius);
  background: rgba(255, 255, 255, 0.52);
}

.page-about .ab-map__dot {
  aspect-ratio: 1 / 1;
  border-radius: 2px;
  background: rgba(28, 37, 48, 0.1);
}

.page-about .ab-map__dot--hi {
  background: var(--wl-gold);
  box-shadow: 0 0 0 3px rgba(201, 162, 39, 0.16);
}

.page-about .ab-coverage__text p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--wl-text-soft);
}

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

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

/* ---------- 合作互校 ---------- */

.page-about .ab-coop {
  background: var(--wl-ink);
  color: var(--wl-on-dark);
}

.page-about .ab-coop .ab-head__lead {
  color: var(--wl-on-dark);
  opacity: 0.82;
}

.page-about .ab-coop__steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  border: 1px solid var(--ab-line);
  border-radius: var(--wl-radius);
  overflow: hidden;
  background: var(--ab-line);
}

.page-about .ab-coop__step {
  padding: 22px 18px 24px;
  background: rgba(18, 40, 63, 0.7);
}

.page-about .ab-coop__num {
  display: block;
  margin-bottom: 12px;
  font-family: var(--wl-font-mono);
  font-size: 15px;
  letter-spacing: 0.08em;
  color: var(--wl-gold-hi);
}

.page-about .ab-coop__step h3 {
  margin: 0 0 10px;
  color: var(--wl-on-dark-strong);
}

.page-about .ab-coop__step p {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--wl-on-dark);
}

/* ---------- 当前版本 ---------- */

.page-about .ab-last {
  background: linear-gradient(180deg, var(--wl-ink) 0%, #091522 100%);
  color: var(--wl-on-dark);
  padding-bottom: 96px;
}

.page-about .ab-last__inner {
  display: grid;
  gap: 30px;
}

.page-about .ab-last__main .ab-head__title {
  margin: 10px 0 16px;
  color: var(--wl-on-dark-strong);
}

.page-about .ab-last__main p {
  margin: 0 0 18px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--wl-on-dark);
  max-width: 40em;
}

.page-about .ab-last__version {
  margin: 22px 0 0;
}

.page-about .ab-next {
  display: grid;
  gap: 1px;
  border: 1px solid var(--ab-line);
  border-radius: var(--wl-radius);
  overflow: hidden;
  background: var(--ab-line);
}

.page-about .ab-next__link {
  display: block;
  padding: 15px 16px;
  background: rgba(11, 26, 43, 0.8);
  color: var(--wl-on-dark-strong);
  font-size: 15px;
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: border-color 0.24s var(--wl-ease), background 0.24s var(--wl-ease);
}

.page-about .ab-next__link:hover {
  background: rgba(18, 40, 63, 0.92);
  border-left-color: var(--wl-gold);
}

/* ---------- 右侧版本锚点 ---------- */

.page-about .ab-jump {
  display: none;
}

/* ---------- 断点 ---------- */

@media (min-width: 600px) {
  .page-about .ab-hero__frame {
    margin: 0 24px;
    padding: 30px 28px 40px;
  }

  .page-about .ab-work__item,
  .page-about .ab-coop__step {
    padding: 26px 24px 30px;
  }

  .page-about .ab-map {
    grid-template-columns: repeat(8, minmax(0, 1fr));
  }
}

@media (min-width: 760px) {
  .page-about .ab-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

@media (min-width: 900px) {
  .page-about .ab-hero {
    padding: 128px 0 84px;
  }

  .page-about .ab-hero__frame {
    margin: 0 auto;
    max-width: calc(var(--wl-maxw) - 48px);
    padding: 38px 44px 50px;
  }

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

  .page-about .ab-team__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    gap: 54px;
    align-items: start;
  }

  .page-about .ab-coverage__body {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    gap: 42px;
    align-items: start;
    margin-bottom: 48px;
  }

  .page-about .ab-last__inner {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    gap: 52px;
    align-items: start;
  }
}

@media (min-width: 1100px) {
  .page-about .ab-coop__steps {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 1180px) {
  .page-about .ab-jump {
    position: fixed;
    right: 22px;
    top: 47%;
    z-index: 5;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    padding: 14px 10px;
    border: 1px solid var(--ab-line);
    border-radius: var(--wl-radius);
    background: rgba(11, 26, 43, 0.88);
    color: var(--wl-gold-hi);
    text-decoration: none;
    font-size: 12px;
    letter-spacing: 0.14em;
    transition: border-color 0.24s var(--wl-ease), background 0.24s var(--wl-ease);
  }

  .page-about .ab-jump:hover {
    border-color: var(--wl-gold);
    background: rgba(18, 40, 63, 0.95);
  }

  .page-about .ab-jump__dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--wl-teal);
    box-shadow: 0 0 8px var(--wl-teal);
  }

  .page-about .ab-jump__label {
    writing-mode: vertical-rl;
    letter-spacing: 0.2em;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-work__item,
  .page-about .ab-bar__fill,
  .page-about .ab-next__link,
  .page-about .ab-jump {
    transition: none;
  }
}