.page-about {
  --about-spine: 78px;
  display: block;
}

.page-about .breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .25rem;
  padding-block: 1.25rem .75rem;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--gray);
}
.page-about .breadcrumbs__item {
  color: var(--mist);
  text-decoration: none;
}
.page-about .breadcrumbs__item + .breadcrumbs__item::before {
  content: "/";
  margin-inline: .5rem;
  color: var(--gray);
}
.page-about a.breadcrumbs__item:hover,
.page-about a.breadcrumbs__item:focus-visible {
  color: var(--teal);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  display: grid;
  gap: 1.75rem;
  padding: clamp(1.4rem, 4vw, 2.9rem);
  background:
    radial-gradient(120% 90% at 0% 0%, rgba(15, 91, 63, .82) 0%, rgba(12, 31, 26, 0) 62%),
    var(--grad-panel);
  border: 2px solid var(--line-strong);
  border-radius: var(--radius);
  box-shadow: var(--shadow-panel);
  overflow: hidden;
}
.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 6px;
  background: var(--grad-signal);
}
.page-about h1 {
  margin: .55rem 0 1rem;
  max-width: 17ch;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.95rem, 6.2vw, 3.45rem);
  line-height: 1.08;
  letter-spacing: -.02em;
  color: var(--paper);
}
.page-about .lede {
  max-width: 60ch;
  color: var(--mist);
  font-size: 1rem;
  line-height: 1.8;
}
.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: .75rem;
  margin-top: 1.5rem;
}
.page-about .about-hero__side {
  align-self: start;
  padding: 1.2rem 1.25rem 1.15rem;
  background: rgba(12, 31, 26, .74);
  border: 2px solid var(--line);
  border-left: 4px solid var(--teal);
  border-radius: var(--radius);
}
.page-about .about-hero__label {
  font-size: .7rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--orange);
}
.page-about .about-hero__facts {
  list-style: none;
  margin: .85rem 0 0;
  padding: 0;
  display: grid;
  gap: .8rem;
}
.page-about .about-hero__facts li {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: .7rem;
  align-items: baseline;
  padding-top: .8rem;
  border-top: 1px dashed var(--line);
  font-size: .88rem;
  line-height: 1.65;
  color: var(--mist);
}
.page-about .about-hero__facts li:first-child {
  padding-top: 0;
  border-top: 0;
}
.page-about .about-hero__facts .mono {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--teal);
}

/* ---------- 堆叠画板 ---------- */
.page-about .board {
  position: relative;
  display: grid;
  margin-top: 1.75rem;
  background: var(--grad-panel);
  border: 2px solid var(--line-strong);
  border-radius: var(--radius);
  box-shadow: var(--shadow-panel);
}
.page-about .board__spine {
  display: flex;
  align-items: center;
  gap: .85rem;
  padding: 1rem clamp(1.1rem, 3vw, 1.6rem);
  background:
    repeating-linear-gradient(90deg, rgba(191, 233, 221, .16) 0 1px, transparent 1px 26px),
    rgba(15, 91, 63, .24);
  border-bottom: 2px solid var(--line-strong);
}
.page-about .board__num {
  font-size: .78rem;
  letter-spacing: .12em;
  color: var(--orange);
}
.page-about .board__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.12rem;
  letter-spacing: -.01em;
  color: var(--paper);
}
.page-about .board__body {
  padding: clamp(1.2rem, 3.4vw, 2.2rem);
}
.page-about .board__body p {
  color: var(--mist);
  line-height: 1.78;
}
.page-about .board__body p + p {
  margin-top: .95rem;
}
.page-about .board__intro {
  max-width: 62ch;
  font-size: .95rem;
}
.page-about .board__cols {
  display: grid;
  gap: 1.6rem;
}
.page-about .board__copy {
  min-width: 0;
}
.page-about .rail__label {
  margin-top: 1rem;
  font-size: .7rem;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--gray);
}
.page-about .rail__label:first-child {
  margin-top: 0;
}
.page-about .rail__value {
  margin-top: .3rem;
  font-size: .88rem;
  line-height: 1.7;
  color: var(--paper);
}

/* ---------- 时间轨道 ---------- */
.page-about .track {
  list-style: none;
  margin: 1.6rem 0 0;
  padding: 0;
  display: grid;
  gap: .85rem;
}
.page-about .track__node {
  position: relative;
  padding: 1.1rem 1rem 1rem;
  background: rgba(12, 31, 26, .66);
  border: 2px solid var(--line);
  border-radius: var(--radius);
  transition: transform .28s cubic-bezier(.2, .7, .2, 1), border-color .28s;
}
.page-about .track__node::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 4px;
  border-radius: var(--radius) var(--radius) 0 0;
  background: var(--grad-signal);
  opacity: .5;
  transition: opacity .28s;
}
.page-about .track__node:hover,
.page-about .track__node:focus-within {
  transform: translateY(-4px);
  border-color: var(--line-strong);
}
.page-about .track__node:hover::before,
.page-about .track__node:focus-within::before {
  opacity: 1;
}
.page-about .track__when {
  font-size: .72rem;
  letter-spacing: .1em;
  color: var(--orange);
}
.page-about .track__name {
  margin: .4rem 0 .4rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1rem;
  color: var(--paper);
}
.page-about .track__text {
  font-size: .85rem;
  line-height: 1.7;
  color: var(--gray);
}

/* ---------- 三级分层 ---------- */
.page-about .layer-grid {
  display: grid;
  gap: 1rem;
  margin-top: 1.5rem;
}
.page-about .layer {
  padding: 1.2rem 1.15rem 1.35rem;
  background: rgba(12, 31, 26, .68);
  border: 2px solid var(--line);
  border-top: 4px solid var(--teal);
  border-radius: var(--radius);
  box-shadow: var(--shadow-soft);
}
.page-about .layer--version {
  border-top-color: var(--orange);
}
.page-about .layer__tag {
  font-size: .7rem;
  letter-spacing: .1em;
  color: var(--gray);
}
.page-about .layer__name {
  margin: .55rem 0 .6rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.05rem;
  color: var(--paper);
}
.page-about .layer__text {
  font-size: .88rem;
  line-height: 1.75;
  color: var(--mist);
}
.page-about .layer__for {
  margin-top: .9rem;
  padding-top: .8rem;
  border-top: 1px dashed var(--line);
  font-size: .78rem;
  color: var(--gray);
}

/* ---------- 图位 ---------- */
.page-about .figure {
  margin: 1.5rem 0 0;
}
.page-about .figure__frame {
  border: 2px solid var(--line-strong);
  border-radius: var(--radius);
  box-shadow: var(--shadow-soft);
  overflow: hidden;
  background: var(--ink-800);
}
.page-about .figure__img,
.page-about .figure__frame img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .figure__caption {
  margin-top: .7rem;
  font-family: var(--font-mono);
  font-size: .74rem;
  line-height: 1.7;
  letter-spacing: .02em;
  color: var(--gray);
}
.page-about .board__cols--media .figure {
  margin-top: 0;
}

/* ---------- 规模看板 ---------- */
.page-about .scale-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 2px;
  margin-top: 1.5rem;
  background: var(--line);
  border: 2px solid var(--line-strong);
  border-radius: var(--radius);
  overflow: hidden;
}
.page-about .stat {
  padding: 1.15rem 1rem 1.2rem;
  background: var(--ink-900);
}
.page-about .stat__value {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.5rem, 4.4vw, 2.2rem);
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--teal);
}
.page-about .stat__value span {
  margin-left: .25rem;
  font-size: .78rem;
  font-weight: 400;
  color: var(--mist);
}
.page-about .stat__label {
  margin-top: .6rem;
  font-size: .8rem;
  line-height: 1.65;
  color: var(--gray);
}

/* ---------- 承诺 ---------- */
.page-about .pledges {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
  background: var(--line);
  border: 2px solid var(--line-strong);
  border-radius: var(--radius);
  overflow: hidden;
}
.page-about .pledge {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1rem;
  align-items: start;
  padding: 1.2rem 1.1rem;
  background: var(--ink-900);
}
.page-about .pledge__idx {
  font-size: .82rem;
  letter-spacing: .1em;
  color: var(--orange);
}
.page-about .pledge__name {
  margin: 0 0 .4rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1rem;
  color: var(--paper);
}
.page-about .pledge__text {
  font-size: .88rem;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 尾段行动 ---------- */
.page-about .about-cta {
  margin-top: 1.5rem;
  padding: clamp(1.2rem, 3.5vw, 1.9rem);
  background:
    linear-gradient(135deg, rgba(15, 91, 63, .9) 0%, rgba(12, 31, 26, .9) 70%),
    var(--ink-800);
  border: 2px solid var(--line-strong);
  border-left: 5px solid var(--orange);
  border-radius: var(--radius);
}
.page-about .about-cta__label {
  font-size: .7rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--orange);
}
.page-about .about-cta__title {
  margin: .6rem 0 1.15rem;
  max-width: 30ch;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.05rem, 2.6vw, 1.35rem);
  line-height: 1.45;
  color: var(--paper);
}
.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: .75rem;
}

/* ---------- 断点 ---------- */
@media (min-width: 820px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.45fr) minmax(0, .85fr);
    align-items: start;
  }
  .page-about .board__cols {
    grid-template-columns: minmax(0, 1.55fr) minmax(0, .85fr);
    align-items: start;
  }
  .page-about .board__cols--media {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
  }
  .page-about .layer-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .scale-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .track {
    grid-template-columns: repeat(auto-fit, minmax(158px, 1fr));
    gap: .8rem;
    padding-top: 1.2rem;
    border-top: 2px solid var(--line-strong);
  }
}

@media (min-width: 960px) {
  .page-about .board {
    grid-template-columns: var(--about-spine) minmax(0, 1fr);
  }
  .page-about .board__spine {
    flex-direction: row;
    align-items: flex-start;
    justify-content: flex-start;
    gap: 1rem;
    padding: 1.6rem .95rem;
    writing-mode: vertical-rl;
    border-bottom: 0;
    border-right: 2px solid var(--line-strong);
    background:
      repeating-linear-gradient(180deg, rgba(191, 233, 221, .18) 0 1px, transparent 1px 24px),
      rgba(15, 91, 63, .24);
  }
  .page-about .board__title {
    font-size: 1.02rem;
    letter-spacing: .08em;
  }
  .page-about .board__num {
    letter-spacing: .2em;
  }
  .page-about .board__body {
    min-width: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .track__node,
  .page-about .track__node::before {
    transition: none;
  }
  .page-about .track__node:hover,
  .page-about .track__node:focus-within {
    transform: none;
  }
}
<<<END>>>