.page-about {
  --about-rail: 6rem;
  display: block;
  background: var(--night);
  color: var(--paper);
}

.page-about .breadcrumb {
  padding-block: clamp(1rem, 2vw, 1.5rem) 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: clamp(1.5rem, 4vw, 2.75rem);
  padding-block: clamp(1.5rem, 4vw, 2.5rem) clamp(2.5rem, 6vw, 4.5rem);
}

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

.page-about .about-hero__eyebrow {
  display: inline-block;
  margin-bottom: 1rem;
}

.page-about .about-hero h1 {
  margin: 0 0 1.25rem;
  font-family: var(--font-display);
  font-size: var(--fs-display);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -0.02em;
  max-width: 15ch;
}

.page-about .about-hero__lede {
  margin: 0;
  max-width: 38em;
  font-size: 1.0625rem;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .scoreboard {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.625rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .scoreboard > li {
  display: grid;
  gap: 0.25rem;
  padding: 0.9375rem 1rem 1.0625rem;
  background: var(--stand);
  border: var(--rule) solid var(--stroke);
  box-shadow: var(--hard-sm);
}

.page-about .scoreboard__num {
  font-family: var(--font-mono);
  font-size: clamp(1.375rem, 1.05rem + 1.5vw, 1.875rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--lime);
}

.page-about .scoreboard__num--amber {
  color: var(--amber);
}

.page-about .scoreboard__key {
  font-size: 0.8125rem;
  line-height: 1.5;
  color: var(--mist);
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  padding-block: clamp(1.5rem, 4vw, 3rem);
}

.page-about .about-timeline__head {
  max-width: 44rem;
  margin-bottom: clamp(1.75rem, 4vw, 3rem);
}

.page-about .about-timeline__head h2 {
  margin: 0.625rem 0 0.75rem;
  font-family: var(--font-display);
  font-size: var(--fs-h2);
  font-weight: 800;
  letter-spacing: -0.02em;
}

.page-about .about-timeline__intro {
  margin: 0;
  max-width: 36em;
  color: var(--mist);
  line-height: 1.8;
  font-size: 0.9375rem;
}

.page-about .about-timeline__list {
  display: grid;
  gap: clamp(1.5rem, 3vw, 2.25rem);
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-node {
  display: grid;
  gap: 0.875rem;
}

.page-about .about-node__scale {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 0.625rem;
  padding-left: 0.875rem;
  border-left: var(--rule) solid var(--stroke);
}

.page-about .about-node__scale::before {
  content: "";
  position: absolute;
  left: -4px;
  top: 0.35em;
  width: 10px;
  height: 10px;
  background: var(--lime);
  box-shadow: 0 0 0 4px var(--night);
}

.page-about .about-node__idx {
  font-family: var(--font-mono);
  font-size: 1.375rem;
  font-weight: 700;
  line-height: 1;
  color: var(--lime);
}

.page-about .about-node__era {
  font-size: 0.8125rem;
  letter-spacing: 0.06em;
  color: var(--mist);
}

.page-about .about-node__panel {
  min-width: 0;
  transition: transform 160ms ease, border-color 160ms ease;
}

.page-about .about-node__panel:hover,
.page-about .about-node__panel:focus-within {
  transform: translateY(-2px);
  border-color: var(--lime);
}

.page-about .about-node__title {
  margin: 0 0 0.625rem;
  font-family: var(--font-display);
  font-size: var(--fs-h3);
  font-weight: 700;
  letter-spacing: -0.01em;
}

.page-about .about-node__text {
  margin: 0 0 0.75rem;
  max-width: 40em;
  color: var(--mist);
  line-height: 1.8;
  font-size: 0.9375rem;
}

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

.page-about .about-node__figure {
  position: relative;
  margin: 1.25rem 0 0;
  overflow: hidden;
  border: var(--rule) solid var(--stroke);
  box-shadow: var(--hard-sm);
}

.page-about .about-node__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  filter: saturate(0.72) brightness(0.85);
}

.page-about .about-node__chip {
  position: absolute;
  left: 0.75rem;
  bottom: 0.75rem;
  padding: 0.2rem 0.55rem;
  background: var(--lime);
  color: var(--edge);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
}

/* ---------- 生产线 ---------- */
.page-about .about-flow {
  padding-block: clamp(2.5rem, 6vw, 5rem);
  margin-block: clamp(1.5rem, 4vw, 3rem);
  background: var(--edge);
  border-top: var(--rule) solid var(--stroke);
  border-bottom: var(--rule) solid var(--stroke);
}

.page-about .about-flow__figure {
  position: relative;
  margin: 0 0 clamp(1.75rem, 4vw, 2.75rem);
  overflow: hidden;
  border: var(--rule) solid var(--stroke);
  box-shadow: var(--hard);
}

.page-about .about-flow__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 45 / 16;
  object-fit: cover;
  filter: saturate(0.68) brightness(0.8);
}

.page-about .about-flow__head {
  max-width: 46rem;
  margin-bottom: clamp(1.5rem, 3.5vw, 2.25rem);
}

.page-about .about-flow__head h2 {
  margin: 0.625rem 0 0.75rem;
  font-family: var(--font-display);
  font-size: var(--fs-h2);
  font-weight: 800;
  letter-spacing: -0.02em;
}

.page-about .about-flow__intro {
  margin: 0;
  max-width: 34em;
  color: var(--mist);
  font-size: 0.9375rem;
  line-height: 1.8;
}

.page-about .about-flow__steps {
  display: grid;
  gap: 0.75rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-flow__step {
  display: grid;
  gap: 0.4rem;
  padding: 1.125rem 1rem 1.25rem;
  background: var(--night);
  border: var(--rule) solid var(--stroke);
  border-top-color: var(--lime);
  transition: background-color 140ms ease, border-color 140ms ease;
}

.page-about .about-flow__step:hover {
  background: var(--stand);
  border-color: var(--lime);
}

.page-about .about-flow__idx {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--lime);
}

.page-about .about-flow__name {
  margin: 0;
  font-family: var(--font-display);
  font-size: 1.0625rem;
  font-weight: 700;
}

.page-about .about-flow__desc {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--mist);
}

/* ---------- 服务范围 ---------- */
.page-about .about-reach {
  display: grid;
  gap: clamp(1.75rem, 4vw, 3rem);
  padding-block: clamp(2rem, 5vw, 4rem);
}

.page-about .about-reach__figure {
  position: relative;
  margin: 0;
  overflow: hidden;
  border: var(--rule) solid var(--stroke);
  box-shadow: var(--hard);
}

.page-about .about-reach__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  filter: saturate(0.7) brightness(0.85);
}

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

.page-about .about-reach__body h2 {
  margin: 0.625rem 0 0.875rem;
  font-family: var(--font-display);
  font-size: var(--fs-h2);
  font-weight: 800;
  letter-spacing: -0.02em;
}

.page-about .about-reach__text {
  margin: 0;
  max-width: 38em;
  color: var(--mist);
  font-size: 0.9375rem;
  line-height: 1.85;
}

.page-about .about-reach__list {
  display: grid;
  gap: 0.875rem;
  margin: clamp(1.25rem, 3vw, 1.75rem) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-reach__item {
  display: grid;
  grid-template-columns: 2.25rem minmax(0, 1fr);
  gap: 0.875rem;
  align-items: start;
  padding-top: 0.875rem;
  border-top: 1px solid var(--stroke);
}

.page-about .about-reach__mark {
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--lime);
}

.page-about .about-reach__item b {
  display: block;
  font-size: 0.9375rem;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-reach__item span {
  display: block;
  margin-top: 0.2rem;
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--mist);
}

/* ---------- 收尾入口 ---------- */
.page-about .about-next {
  padding-block: clamp(2rem, 5vw, 4rem) clamp(3rem, 6vw, 5rem);
}

.page-about .about-next__panel h2 {
  margin: 0.625rem 0 0.75rem;
  font-family: var(--font-display);
  font-size: var(--fs-h2);
  font-weight: 800;
  letter-spacing: -0.02em;
}

.page-about .about-next__text {
  margin: 0 0 1.5rem;
  max-width: 34em;
  color: var(--mist);
  font-size: 0.9375rem;
  line-height: 1.8;
}

.page-about .about-next__links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.625rem;
}

.page-about .about-next__links .btn {
  flex: 1 1 auto;
  justify-content: center;
  min-width: 9rem;
  text-align: center;
}

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

@media (min-width: 760px) {
  .page-about .about-node {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(1rem, 2vw, 1.75rem);
  }

  .page-about .about-node__scale {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.375rem;
  }

  .page-about .about-node--offset .about-node__panel {
    transform: translateY(14px);
  }
}

@media (min-width: 800px) {
  .page-about .about-flow__steps {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr);
    align-items: end;
  }

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

  .page-about .scoreboard > li:nth-child(2) {
    transform: translateY(-14px);
  }

  .page-about .scoreboard > li:nth-child(3) {
    transform: translateY(12px);
  }

  .page-about .about-reach {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: center;
    gap: clamp(1.75rem, 4vw, 4rem);
  }

  .page-about .about-node--offset {
    margin-left: -1rem;
  }
}

@media (max-width: 639px) {
  .page-about .about-flow__figure img {
    aspect-ratio: 16 / 9;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-node__panel,
  .page-about .about-flow__step {
    transition: none;
  }

  .page-about .about-node__panel:hover,
  .page-about .about-node__panel:focus-within {
    transform: none;
  }

  .page-about .scoreboard > li,
  .page-about .about-node--offset .about-node__panel {
    transform: none;
  }
}