.page-about {
  --about-gap: clamp(24px, 4vw, 56px);
  --about-rule: 1px solid var(--line-soft);
  background: var(--c-void);
  color: var(--c-white);
}

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

/* ---------- Hero ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(112px, 15vw, 176px) 0 clamp(32px, 5vw, 56px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -22%;
  right: -18%;
  width: min(680px, 92vw);
  height: min(680px, 92vw);
  background: radial-gradient(circle, rgba(53, 227, 176, 0.15), rgba(6, 17, 13, 0) 68%);
  pointer-events: none;
}

.page-about .breadcrumb__list {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 clamp(24px, 4vw, 40px);
  padding: 0;
  list-style: none;
  font-family: var(--f-mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  color: var(--ink-dim);
}

.page-about .breadcrumb__link {
  color: var(--ink-dim);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .breadcrumb__link:hover,
.page-about .breadcrumb__link:focus-visible {
  color: var(--c-neon);
  border-bottom-color: var(--c-neon);
}

.page-about .breadcrumb__current {
  color: var(--c-white);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 4vw, 48px);
}

.page-about .about-hero__title {
  margin: 12px 0 0;
  font-family: var(--f-display);
  font-size: clamp(2.3rem, 6.2vw, 4.9rem);
  font-weight: 900;
  line-height: 0.96;
  letter-spacing: 0.01em;
  color: var(--c-white);
  text-wrap: balance;
}

.page-about .about-hero__lede {
  max-width: 60ch;
  margin: 24px 0 0;
  font-size: clamp(1rem, 1.6vw, 1.125rem);
  line-height: 1.85;
  color: var(--ink-body);
}

.page-about .about-hero__side {
  border-top: 1px solid var(--line-mid);
  padding-top: 8px;
}

.page-about .about-facts {
  margin: 0;
}

.page-about .about-fact {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding: 11px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-fact__key {
  margin: 0;
  font-size: 0.8125rem;
  letter-spacing: 0.04em;
  color: var(--ink-dim);
}

.page-about .about-fact__val {
  margin: 0;
  font-family: var(--f-mono);
  font-size: 1rem;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: var(--c-mint);
}

.page-about .about-hero__figure {
  margin: clamp(28px, 4vw, 52px) 0 0;
}

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

/* ---------- 章节索引 ---------- */
.page-about .about-index {
  position: sticky;
  top: 72px;
  z-index: 6;
  background: rgba(6, 17, 13, 0.94);
  border-top: var(--about-rule);
  border-bottom: var(--about-rule);
}

.page-about .about-index__list {
  display: flex;
  gap: 6px;
  margin: 0;
  padding: 10px 0;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
}

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

.page-about .about-index__link {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding: 6px 12px;
  white-space: nowrap;
  font-size: 0.8125rem;
  color: var(--ink-dim);
  text-decoration: none;
  border: 1px solid transparent;
  border-radius: var(--radius);
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease), background 0.2s var(--ease);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--c-white);
  border-color: var(--line-mid);
}

.page-about .about-index__link[aria-current="true"] {
  color: var(--c-neon);
  border-color: var(--c-neon);
  background: rgba(53, 227, 176, 0.08);
}

.page-about .about-index__num {
  font-family: var(--f-mono);
  font-size: 0.6875rem;
  color: var(--c-amber);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-main {
  padding-bottom: clamp(40px, 6vw, 80px);
}

.page-about .chapter {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(18px, 3vw, 32px);
  padding: clamp(40px, 6vw, 82px) 0;
  border-top: var(--about-rule);
}

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

.page-about .chapter__rail {
  display: flex;
  align-items: baseline;
  gap: 14px;
}

.page-about .chapter__mark {
  font-family: var(--f-display);
  font-size: clamp(2.4rem, 5vw, 4rem);
  font-weight: 900;
  line-height: 0.82;
  letter-spacing: 0.02em;
  color: var(--c-neon);
  opacity: 0.3;
}

.page-about .chapter__years {
  font-family: var(--f-mono);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  color: var(--c-amber);
  white-space: nowrap;
}

.page-about .chapter__title {
  max-width: 24ch;
  margin: 0 0 18px;
  font-family: var(--f-head);
  font-size: clamp(1.4rem, 2.6vw, 2.15rem);
  font-weight: 800;
  line-height: 1.28;
  color: var(--c-white);
}

.page-about .chapter__body > p {
  max-width: 68ch;
  margin: 0 0 16px;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--ink-body);
}

.page-about .chapter__note {
  margin-top: 22px;
  padding-left: 16px;
  border-left: 2px solid var(--c-amber);
  max-width: 62ch;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--c-mint);
}

/* ---------- 浅雾章节 ---------- */
.page-about .chapter--fog {
  background: var(--c-fog);
  border-top: 0;
  padding-inline: clamp(16px, 3vw, 34px);
  color: var(--c-deep);
}

.page-about .chapter--fog .chapter__mark {
  color: var(--c-deep);
  opacity: 0.22;
}

.page-about .chapter--fog .chapter__years {
  color: #8a5c00;
}

.page-about .chapter--fog .chapter__title {
  color: var(--c-deep);
}

/* ---------- 服务对象卡片 ---------- */
.page-about .scenes {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: 8px;
}

.page-about .scene {
  padding: 20px;
  background: rgba(255, 255, 255, 0.52);
  border: 1px solid rgba(12, 36, 29, 0.16);
  border-radius: var(--radius);
  transition: transform 0.25s var(--ease), border-color 0.25s var(--ease);
}

.page-about .scene:hover {
  transform: translateY(-2px);
  border-color: rgba(12, 36, 29, 0.4);
}

.page-about .scene .chip {
  margin: 0 0 12px;
  color: var(--c-deep);
  background: rgba(12, 36, 29, 0.08);
  border-color: rgba(12, 36, 29, 0.2);
}

.page-about .scene__title {
  margin: 0 0 10px;
  font-family: var(--f-head);
  font-size: 1.125rem;
  font-weight: 800;
  line-height: 1.4;
  color: var(--c-deep);
}

.page-about .scene__text {
  margin: 0 0 12px;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: rgba(12, 36, 29, 0.78);
}

.page-about .scene__list {
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 0.8125rem;
  line-height: 1.9;
  color: rgba(12, 36, 29, 0.66);
}

.page-about .scene__list li {
  position: relative;
  padding-left: 14px;
}

.page-about .scene__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 5px;
  height: 1px;
  background: #1f8f6d;
}

/* ---------- 时间轴 ---------- */
.page-about .timeline {
  display: flex;
  gap: 14px;
  margin: 24px 0 0;
  padding: 0 0 16px;
  list-style: none;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
}

.page-about .timeline__item {
  position: relative;
  flex: 0 0 min(272px, 78vw);
  scroll-snap-align: start;
  padding: 22px 18px 20px;
  background: var(--c-deep);
  border: var(--about-rule);
  border-radius: var(--radius);
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 2px;
  background: var(--c-venue);
}

.page-about .timeline__item:first-child::before {
  background: var(--c-neon);
}

.page-about .timeline__year {
  display: block;
  font-family: var(--f-mono);
  font-size: 1.0625rem;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: var(--c-amber);
}

.page-about .timeline__phase {
  display: inline-block;
  margin: 8px 0 10px;
  padding: 2px 8px;
  font-size: 0.6875rem;
  letter-spacing: 0.08em;
  color: var(--c-mint);
  border: 1px solid var(--line-mid);
  border-radius: var(--radius);
}

.page-about .timeline__desc {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.8;
  color: var(--ink-body);
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 32px);
  margin-top: 6px;
}

.page-about .roles {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin-top: 20px;
}

.page-about .role {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 14px;
  border: var(--about-rule);
  border-left: 2px solid var(--c-venue);
  background: var(--c-deep);
}

.page-about .role__num {
  font-family: var(--f-mono);
  font-size: 1.25rem;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: var(--c-neon);
}

.page-about .role__name {
  font-size: 0.875rem;
  font-weight: 700;
  color: var(--c-white);
}

.page-about .role__desc {
  font-size: 0.75rem;
  line-height: 1.7;
  color: var(--ink-dim);
}

.page-about .flow {
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
  counter-reset: flowstep;
}

.page-about .flow li {
  position: relative;
  counter-increment: flowstep;
  padding: 0 0 14px 38px;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--ink-body);
}

.page-about .flow li::before {
  content: "0" counter(flowstep);
  position: absolute;
  left: 0;
  top: 2px;
  font-family: var(--f-mono);
  font-size: 0.75rem;
  color: var(--c-neon);
  letter-spacing: 0.04em;
}

.page-about .team-grid__figure {
  margin: 0;
}

.page-about .team-grid__figure img,
.page-about .ecosystem__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 合作生态 ---------- */
.page-about .ecosystem {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 36px);
  margin-top: 6px;
}

.page-about .ecosystem__figure {
  margin: 0;
  max-width: 420px;
}

.page-about .ecosystem__body p {
  max-width: 62ch;
  margin: 0 0 16px;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--ink-body);
}

.page-about .metrics {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: 24px;
  background: var(--line-soft);
  border: var(--about-rule);
}

.page-about .metric {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 18px 16px;
  background: var(--c-deep);
}

.page-about .metric__num {
  font-family: var(--f-mono);
  font-size: clamp(1.35rem, 2.4vw, 1.85rem);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  line-height: 1.1;
  color: var(--c-neon);
}

.page-about .metric__label {
  font-size: 0.75rem;
  letter-spacing: 0.02em;
  color: var(--ink-dim);
}

/* ---------- 服务原则 ---------- */
.page-about .principles {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 20px;
  margin-top: 24px;
}

.page-about .principle {
  padding-left: 16px;
  border-left: 2px solid var(--c-amber);
}

.page-about .principle__title {
  margin: 0 0 8px;
  font-family: var(--f-head);
  font-size: 1.0625rem;
  font-weight: 800;
  color: var(--c-white);
}

.page-about .principle__text {
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--ink-body);
}

/* ---------- 收尾引导 ---------- */
.page-about .about-cta {
  margin-top: clamp(32px, 5vw, 56px);
  padding-top: clamp(24px, 4vw, 40px);
  border-top: 1px solid var(--line-mid);
}

.page-about .about-cta__title {
  margin: 0 0 10px;
  font-family: var(--f-head);
  font-size: clamp(1.15rem, 2vw, 1.5rem);
  font-weight: 800;
  line-height: 1.4;
  color: var(--c-mint);
}

.page-about .about-cta__text {
  max-width: 56ch;
  margin: 0 0 20px;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--ink-body);
}

.page-about .about-cta__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .principles {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }
}

@media (min-width: 860px) {
  .page-about .ecosystem {
    grid-template-columns: minmax(0, 0.78fr) minmax(0, 1.22fr);
    align-items: start;
  }

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

  .page-about .team-grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: start;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: end;
    gap: clamp(32px, 5vw, 72px);
  }

  .page-about .chapter {
    grid-template-columns: 150px minmax(0, 1fr);
    gap: var(--about-gap);
  }

  .page-about .chapter__rail {
    flex-direction: column;
    gap: 10px;
  }

  .page-about .chapter--fog {
    padding-inline: clamp(24px, 4vw, 48px);
  }
}

@media (min-width: 1000px) {
  .page-about .scenes {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    gap: 16px;
  }

  .page-about .scene:nth-child(1) {
    grid-column: span 7;
  }

  .page-about .scene:nth-child(2) {
    grid-column: span 5;
  }

  .page-about .scene:nth-child(3) {
    grid-column: span 12;
  }

  .page-about .scene--wide {
    display: grid;
    grid-template-columns: minmax(0, 0.42fr) minmax(0, 0.58fr);
    align-items: start;
    gap: 8px 24px;
  }

  .page-about .scene--wide .chip {
    grid-column: 1 / -1;
  }

  .page-about .scene--wide .scene__title {
    grid-column: 1;
    margin-bottom: 0;
  }

  .page-about .scene--wide .scene__text {
    grid-column: 2;
    grid-row: 2 / span 2;
    margin-bottom: 0;
  }

  .page-about .about-index {
    top: 76px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .scene,
  .page-about .about-index__link,
  .page-about .breadcrumb__link {
    transition: none;
  }

  .page-about .scene:hover {
    transform: none;
  }
}