.page-about {
  --about-note: 188px;
  --about-anchor-offset: 132px;
  background: var(--ink-900);
  color: var(--text);
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb {
  padding: 12px 0;
  background: var(--ink-850);
  border-bottom: 1px solid var(--line);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(28px, 5vw, 60px) 0 clamp(32px, 5vw, 64px);
  background:
    radial-gradient(92% 118% at 88% -12%, rgba(109, 59, 245, .28), transparent 62%),
    radial-gradient(58% 78% at 0% 102%, rgba(55, 230, 217, .10), transparent 62%),
    var(--ink-900);
}

.page-about .about-hero__frame {
  position: relative;
  padding: clamp(22px, 4vw, 54px) clamp(18px, 4vw, 52px);
  border: 1px solid var(--line);
  background: linear-gradient(160deg, rgba(28, 18, 54, .72), rgba(8, 6, 15, .22) 72%);
}

.page-about .about-hero__frame::before {
  content: "";
  position: absolute;
  inset: 8px;
  pointer-events: none;
  background-image:
    linear-gradient(var(--cyan), var(--cyan)),
    linear-gradient(var(--cyan), var(--cyan)),
    linear-gradient(var(--cyan), var(--cyan)),
    linear-gradient(var(--cyan), var(--cyan)),
    linear-gradient(var(--cyan), var(--cyan)),
    linear-gradient(var(--cyan), var(--cyan)),
    linear-gradient(var(--cyan), var(--cyan)),
    linear-gradient(var(--cyan), var(--cyan));
  background-size:
    16px 1px, 1px 16px,
    16px 1px, 1px 16px,
    16px 1px, 1px 16px,
    16px 1px, 1px 16px;
  background-position:
    left top, left top,
    right top, right top,
    left bottom, left bottom,
    right bottom, right bottom;
  background-repeat: no-repeat;
  opacity: .75;
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  max-width: 20ch;
  font-size: var(--fs-display);
  font-weight: 900;
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-about .about-hero__lede {
  margin: 22px 0 0;
  max-width: 64ch;
  font-size: var(--fs-body);
  line-height: 1.85;
  color: var(--text);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px 20px;
  margin: 32px 0 0;
  padding: 22px 0 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

@media (min-width: 640px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .about-hero__media {
  margin: clamp(24px, 4vw, 40px) 0 0;
}

/* ---------- 章节骨架 ---------- */
.page-about .about-chapter {
  padding: clamp(38px, 6vw, 84px) 0;
  border-bottom: 1px solid var(--line);
  scroll-margin-top: var(--about-anchor-offset);
}

.page-about .about-chapter--alt {
  background: var(--ink-800);
}

.page-about .about-chapter:target {
  background-image: linear-gradient(96deg, rgba(109, 59, 245, .14), transparent 62%);
}

.page-about .about-chapter__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
}

@media (min-width: 880px) {
  .page-about .about-chapter__grid {
    grid-template-columns: var(--about-note) minmax(0, 1fr);
    gap: 0 clamp(30px, 4vw, 68px);
  }
}

/* ---------- 左侧窄栏注释 ---------- */
.page-about .about-note {
  padding-left: 14px;
  border-left: 2px solid var(--line);
}

@media (min-width: 880px) {
  .page-about .about-note {
    position: sticky;
    top: var(--about-anchor-offset);
    align-self: start;
  }
}

.page-about .about-note__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.75rem;
  font-weight: 700;
  line-height: 1;
  color: var(--neon);
}

.page-about .about-note__label {
  display: block;
  margin-top: 9px;
  font-family: var(--font-mono);
  font-size: var(--fs-label);
  letter-spacing: .12em;
  color: var(--neon-soft);
  text-shadow: 0 0 10px rgba(169, 123, 255, .38);
}

.page-about .about-note__text {
  margin: 12px 0 0;
  font-size: .85rem;
  line-height: 1.7;
  color: var(--text-dim);
}

/* ---------- 正文 ---------- */
.page-about .about-body {
  min-width: 0;
}

.page-about .about-body__title {
  margin: 0 0 20px;
  font-size: var(--fs-h2);
  font-weight: 900;
  line-height: 1.14;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-about .about-body__anchor {
  margin-left: 10px;
  font-family: var(--font-mono);
  font-size: .62em;
  font-weight: 400;
  color: var(--line);
  text-decoration: none;
  transition: color .2s var(--ease);
}

.page-about .about-body__anchor:hover,
.page-about .about-body__anchor:focus-visible {
  color: var(--cyan);
}

.page-about .about-body > p {
  max-width: 68ch;
  margin: 0 0 18px;
  font-size: var(--fs-body);
  line-height: 1.85;
  color: var(--text);
}

.page-about .about-body > p:last-child {
  margin-bottom: 0;
}

.page-about .about-inline-link {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(55, 230, 217, .45);
  transition: border-color .2s var(--ease), color .2s var(--ease);
}

.page-about .about-inline-link:hover,
.page-about .about-inline-link:focus-visible {
  color: var(--white);
  border-bottom-color: var(--cyan);
}

/* ---------- 板块列表 ---------- */
.page-about .about-sectors {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 0;
  margin: 26px 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}

.page-about .about-sectors__item {
  padding: 15px 16px 18px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: rgba(28, 18, 54, .34);
  transition: background .2s var(--ease);
}

.page-about .about-sectors__item:hover {
  background: rgba(109, 59, 245, .14);
}

.page-about .about-sectors__name {
  display: block;
  margin-bottom: 7px;
  font-family: var(--font-mono);
  font-size: .88rem;
  letter-spacing: .08em;
  color: var(--white);
}

.page-about .about-sectors__desc {
  display: block;
  font-size: .85rem;
  line-height: 1.65;
  color: var(--text-dim);
}

/* ---------- 团队列表 ---------- */
.page-about .about-team {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .about-team__item {
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
}

@media (min-width: 620px) {
  .page-about .about-team__item {
    display: grid;
    grid-template-columns: 132px minmax(0, 1fr);
    gap: 0 22px;
    align-items: start;
  }
}

.page-about .about-team__key {
  display: block;
  margin-bottom: 7px;
  font-family: var(--font-mono);
  font-size: .82rem;
  letter-spacing: .06em;
  color: var(--neon-soft);
}

@media (min-width: 620px) {
  .page-about .about-team__key {
    margin-bottom: 0;
  }
}

.page-about .about-team__text {
  font-size: .95rem;
  line-height: 1.8;
  color: var(--text);
}

/* ---------- 四级结构图 ---------- */
.page-about .about-map {
  margin: 30px 0;
  padding: 22px 18px 16px;
  border: 1px solid var(--line);
  background: rgba(12, 9, 24, .62);
}

.page-about .about-map__svg {
  display: block;
  width: 100%;
  max-width: 440px;
  height: auto;
  margin: 0 auto;
}

.page-about .about-map__node rect {
  fill: rgba(109, 59, 245, .12);
  stroke: var(--line);
  stroke-width: 1;
  transition: fill .2s var(--ease), stroke .2s var(--ease);
}

.page-about .about-map__node:hover rect {
  fill: rgba(55, 230, 217, .16);
  stroke: var(--cyan);
}

.page-about .about-map__label {
  fill: var(--text);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .04em;
}

.page-about .about-map__node:hover .about-map__label {
  fill: var(--white);
}

.page-about .about-map__cap {
  margin: 14px 0 0;
  text-align: center;
  font-family: var(--font-mono);
  font-size: var(--fs-label);
  letter-spacing: .08em;
  color: var(--text-dim);
}

/* ---------- 版本刻度带 ---------- */
.page-about .about-band {
  padding: clamp(28px, 4vw, 46px) 0;
  background: var(--ink-850);
  border-bottom: 1px solid var(--line);
}

.page-about .about-band__list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px 16px;
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
}

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

.page-about .about-band__item {
  position: relative;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}

.page-about .about-band__item::before {
  content: "";
  position: absolute;
  top: -4px;
  left: 0;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--line);
  transition: background .45s var(--ease), box-shadow .45s var(--ease);
}

.page-about .about-band__item:nth-child(2)::before { transition-delay: .04s; }
.page-about .about-band__item:nth-child(3)::before { transition-delay: .08s; }
.page-about .about-band__item:nth-child(4)::before { transition-delay: .12s; }

.page-about .about-band__item.is-visible::before {
  background: var(--cyan);
  box-shadow: var(--glow-cyan);
}

.page-about .about-band__year {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.3rem;
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--white);
}

.page-about .about-band__label {
  display: block;
  margin-top: 7px;
  font-size: .86rem;
  line-height: 1.6;
  color: var(--text-dim);
}

/* ---------- 图 ---------- */
.page-about .about-figure {
  margin: 30px 0;
}

.page-about .about-figure--square {
  max-width: 440px;
}

/* ---------- 结尾行动区 ---------- */
.page-about .about-cta {
  padding: clamp(40px, 6vw, 84px) 0;
  background:
    radial-gradient(82% 118% at 18% 0%, rgba(109, 59, 245, .24), transparent 66%),
    var(--ink-900);
}

.page-about .about-cta__box {
  padding: clamp(24px, 4vw, 52px);
  border: 1px solid var(--line);
  background: linear-gradient(150deg, rgba(28, 18, 54, .82), rgba(8, 6, 15, .38));
}

.page-about .about-cta__title {
  margin: 12px 0 16px;
  font-size: var(--fs-h2);
  font-weight: 900;
  line-height: 1.14;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-about .about-cta__text {
  margin: 0;
  max-width: 62ch;
  font-size: var(--fs-body);
  line-height: 1.85;
  color: var(--text);
}

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

@media (max-width: 520px) {
  .page-about .about-cta__actions .btn {
    flex: 1 1 100%;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-band__item::before,
  .page-about .about-sectors__item,
  .page-about .about-map__node rect,
  .page-about .about-body__anchor,
  .page-about .about-inline-link {
    transition: none;
  }
}