.page-about {
  --about-grid: 104px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(40px, 7vw, 88px) 0 clamp(30px, 4.5vw, 52px);
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(180deg, rgba(56, 214, 224, 0.08), rgba(11, 27, 43, 0) 76%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: 0.35;
  background-image: linear-gradient(to right, rgba(41, 66, 87, 0.6) 1px, transparent 1px);
  background-size: var(--about-grid) 100%;
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.9), transparent 92%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.9), transparent 92%);
}

.page-about .about-hero > .container {
  position: relative;
  z-index: 1;
}

.page-about .about-hero .crumbs {
  margin-bottom: clamp(20px, 3vw, 32px);
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  max-width: 900px;
  font-size: clamp(31px, 6.2vw, 74px);
  font-weight: 800;
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--text);
}

.page-about .about-hero__lede {
  margin: clamp(18px, 2.6vw, 26px) 0 0;
  max-width: 62ch;
  font-size: clamp(15px, 1.6vw, 17.5px);
  line-height: 1.8;
  color: var(--muted);
}

.page-about .hero-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px 20px;
  margin: clamp(28px, 4vw, 42px) 0 0;
  padding: clamp(20px, 3vw, 26px) 0 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.page-about .hero-fact {
  min-width: 0;
  padding-left: 16px;
  border-left: 2px solid var(--line);
}

.page-about .hero-fact__k {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--muted);
}

.page-about .hero-fact__v {
  display: block;
  margin-top: 8px;
  font-size: clamp(18px, 2.4vw, 25px);
  font-weight: 700;
  line-height: 1.2;
  color: var(--paper);
}

.page-about .about-jump {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: clamp(24px, 3.4vw, 34px);
}

.page-about .about-jump a {
  padding: 7px 11px;
  border: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: var(--muted);
  text-decoration: none;
  transition: color 160ms var(--ease), border-color 160ms var(--ease);
}

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

/* ---------- 章节骨架 ---------- */
.page-about .chapters {
  padding-bottom: clamp(10px, 2vw, 20px);
}

.page-about .chapter {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  padding: clamp(34px, 5.4vw, 66px) 0;
  border-top: 1px solid var(--line);
}

.page-about .chapter:first-child {
  border-top: 0;
}

.page-about .chapter__code {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-family: var(--font-mono);
}

.page-about .chapter__no {
  font-size: 12px;
  letter-spacing: 0.22em;
  color: var(--cyan);
}

.page-about .chapter__name {
  font-size: 11.5px;
  letter-spacing: 0.22em;
  color: var(--muted);
}

.page-about .chapter__body {
  min-width: 0;
}

.page-about .chapter__title {
  margin: 0 0 clamp(14px, 2vw, 20px);
  font-size: clamp(23px, 3.3vw, 38px);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -0.01em;
  color: var(--text);
}

.page-about .chapter__lede {
  margin: 0 0 14px;
  max-width: 66ch;
  font-size: clamp(15px, 1.5vw, 16.5px);
  line-height: 1.8;
  color: var(--muted);
}

.page-about .chapter__lede:last-child {
  margin-bottom: 0;
}

.page-about .inline-link {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(56, 214, 224, 0.45);
  transition: border-color 160ms var(--ease);
}

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

/* ---------- 起点清单 ---------- */
.page-about .starters {
  list-style: none;
  margin: clamp(22px, 3vw, 30px) 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .starter {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 4px;
  padding: 15px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .starter__k {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--orange);
}

.page-about .starter__v {
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--text);
}

/* ---------- 图片区 ---------- */
.page-about .plate {
  margin: clamp(28px, 4vw, 46px) 0 0;
}

.page-about .plate--tight {
  margin-top: clamp(24px, 3.4vw, 36px);
}

.page-about .plate figcaption,
.page-about .history__fig figcaption {
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  line-height: 1.7;
  color: var(--muted);
}

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

/* ---------- 方法列表 ---------- */
.page-about .method {
  list-style: none;
  margin: clamp(22px, 3vw, 30px) 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .method__item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 6px;
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .method__no {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .method__title {
  font-size: 17px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--text);
}

.page-about .method__desc {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--muted);
}

.page-about .tagrow {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: clamp(18px, 2.4vw, 24px) 0 0;
  padding: 0;
  list-style: none;
}

/* ---------- 发展历程 ---------- */
.page-about .history {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 44px);
  margin-top: clamp(22px, 3vw, 30px);
}

.page-about .timeline {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 26px;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan), var(--line) 55%, var(--line));
}

.page-about .stage {
  position: relative;
  padding-bottom: clamp(22px, 3vw, 30px);
}

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

.page-about .stage::before {
  content: "";
  position: absolute;
  left: -25px;
  top: 11px;
  width: 12px;
  height: 2px;
  background: var(--cyan);
}

.page-about .stage__meta {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--orange);
}

.page-about .stage__title {
  margin: 6px 0 8px;
  font-size: clamp(18px, 2.2vw, 22px);
  font-weight: 800;
  line-height: 1.35;
  color: var(--text);
}

.page-about .stage__lede {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--muted);
}

.page-about .stage .expand {
  margin-top: 10px;
}

.page-about .stage .expand__trigger {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--cyan);
}

.page-about .stage .expand__panel {
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--muted);
}

.page-about .history__fig {
  margin: 0;
  align-self: start;
}

/* ---------- 团队数字 ---------- */
.page-about .team-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(22px, 3vw, 30px) 0 0;
  padding: 1px;
  list-style: none;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .team-stat {
  min-width: 0;
  padding: 16px 15px 18px;
  background: var(--ink-deep);
  transition: background-color 180ms var(--ease);
}

.page-about .team-stat:hover {
  background: rgba(56, 214, 224, 0.08);
}

.page-about .team-stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(24px, 3.4vw, 32px);
  font-weight: 700;
  line-height: 1.05;
  color: var(--paper);
}

.page-about .team-stat__num em {
  margin-left: 2px;
  font-style: normal;
  font-size: 0.56em;
  color: var(--orange);
}

.page-about .team-stat__k {
  display: block;
  margin-top: 8px;
  font-size: 12.5px;
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: var(--muted);
}

/* ---------- 两条路径 ---------- */
.page-about .paths {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin: clamp(22px, 3vw, 30px) 0 clamp(20px, 2.6vw, 26px);
}

.page-about .path-card {
  border: 1px solid var(--line);
  border-top: 2px solid var(--cyan);
  padding: 20px 20px 22px;
  background: rgba(56, 214, 224, 0.05);
}

.page-about .path-card--alt {
  border-top-color: var(--orange);
  background: rgba(255, 138, 61, 0.05);
}

.page-about .path-card__k {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--muted);
}

.page-about .path-card__t {
  margin: 10px 0 10px;
  font-size: 19px;
  font-weight: 800;
  line-height: 1.35;
  color: var(--text);
}

.page-about .path-card__d {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--muted);
}

/* ---------- 延伸入口 ---------- */
.page-about .next {
  border-top: 1px solid var(--line);
  padding: clamp(36px, 5vw, 68px) 0 clamp(48px, 6vw, 84px);
  background: linear-gradient(180deg, rgba(7, 19, 31, 0.7), rgba(11, 27, 43, 0));
}

.page-about .next__title {
  margin: 0;
  font-size: clamp(24px, 3vw, 34px);
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--text);
}

.page-about .next__lede {
  margin: 12px 0 0;
  max-width: 52ch;
  font-size: 15px;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .next-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: clamp(24px, 3vw, 34px);
}

.page-about .next-link {
  display: block;
  min-width: 0;
  padding: 20px 20px 22px;
  border: 1px solid var(--line);
  text-decoration: none;
  color: var(--text);
  transition: border-color 180ms var(--ease), background-color 180ms var(--ease);
}

.page-about .next-link:hover,
.page-about .next-link:focus-visible {
  border-color: var(--cyan);
  background: rgba(56, 214, 224, 0.07);
}

.page-about .next-link__code {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .next-link__title {
  display: block;
  margin-top: 10px;
  font-size: 18px;
  font-weight: 700;
}

.page-about .next-link__desc {
  display: block;
  margin-top: 8px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .hero-facts {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .starter {
    grid-template-columns: 128px minmax(0, 1fr);
    gap: 16px;
    align-items: baseline;
  }
}

@media (min-width: 820px) {
  .page-about .method__item {
    grid-template-columns: 52px minmax(0, 168px) minmax(0, 1fr);
    gap: 22px;
    align-items: start;
  }

  .page-about .paths {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }

  .page-about .next-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
  }
}

@media (min-width: 900px) {
  .page-about .chapter {
    grid-template-columns: 128px minmax(0, 1fr);
    column-gap: clamp(26px, 4vw, 58px);
    gap: 0;
  }

  .page-about .chapter__code {
    flex-direction: column;
    align-items: flex-start;
    gap: 7px;
    padding-top: 11px;
    padding-right: 18px;
    border-right: 1px solid var(--line);
  }

  .page-about .history {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    align-items: start;
  }

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

@media (min-width: 1080px) {
  .page-about .chapter {
    grid-template-columns: 156px minmax(0, 1fr);
  }

  .page-about .next-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}
<<<PAGE_CSS_END>>>