.page-about {
  --about-gap: clamp(2.4rem, 6vw, 4rem);
  background: var(--graphite);
  color: var(--paper);
  font-family: var(--f-body);
  padding-bottom: clamp(3rem, 8vw, 6rem);
  overflow-x: hidden;
}

.page-about .breadcrumb {
  margin-top: clamp(1rem, 3vw, 1.6rem);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(1.5rem, 4vw, 3rem);
  margin-top: clamp(1.6rem, 4vw, 2.4rem);
  align-items: end;
}

.page-about .about-hero__copy h1 {
  font-family: var(--f-display);
  font-weight: 800;
  font-size: clamp(2rem, 5.4vw, 3.6rem);
  line-height: 1.08;
  letter-spacing: -0.015em;
  margin: 0.7rem 0 1rem;
  color: var(--paper);
  max-width: 15em;
}

.page-about .about-hero__copy .lede {
  max-width: 32em;
  color: var(--mist);
  font-size: clamp(0.98rem, 1.6vw, 1.08rem);
  line-height: 1.85;
  margin: 0;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin-top: 1.6rem;
}

.page-about .about-hero__media {
  margin: 0;
  position: relative;
  overflow: hidden;
  background: var(--zone-teal);
  border: 1px solid var(--line);
  clip-path: polygon(0 5%, 100% 0, 100% 100%, 0 100%);
}

.page-about .about-hero__media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(200deg, rgba(51, 224, 212, 0.16), transparent 46%, rgba(255, 122, 47, 0.14));
  pointer-events: none;
}

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

/* ---------- 规模条 ---------- */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: clamp(2rem, 5vw, 3.2rem);
  background: var(--line-soft);
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow: hidden;
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  padding: 1.1rem 1.05rem 1.25rem;
  background: var(--panel);
}

.page-about .about-stat__num {
  font-family: var(--f-mono);
  font-size: clamp(1.25rem, 2.8vw, 1.8rem);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--cyan);
}

.page-about .about-stat__label {
  font-size: 0.76rem;
  line-height: 1.55;
  color: var(--mist);
}

/* ---------- 纵向主骨架 ---------- */
.page-about .about-stream {
  position: relative;
  margin-top: var(--about-gap);
}

.page-about .about-block {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.75rem;
  scroll-margin-top: 5rem;
}

.page-about .about-block + .about-block {
  margin-top: clamp(2.2rem, 5.5vw, 3.4rem);
}

.page-about .about-block__rail {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
}

.page-about .about-block__num {
  font-family: var(--f-mono);
  font-size: clamp(1.3rem, 2.6vw, 1.85rem);
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--steel);
}

.page-about .about-block__kick {
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .about-block__body h2 {
  font-family: var(--f-display);
  font-weight: 800;
  font-size: clamp(1.4rem, 3vw, 2rem);
  line-height: 1.24;
  letter-spacing: -0.01em;
  margin: 0 0 0.9rem;
  color: var(--paper);
}

.page-about .prose p {
  max-width: 34em;
  margin: 0 0 0.9rem;
  color: var(--mist);
  font-size: 0.97rem;
  line-height: 1.9;
}

.page-about .about-facts {
  list-style: none;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.55rem;
  margin: 1.3rem 0 0;
  padding: 0;
}

.page-about .about-facts li {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  font-size: 0.86rem;
  line-height: 1.6;
  color: var(--mist);
  padding: 0.6rem 0.85rem;
  background: var(--panel);
  border-left: 2px solid var(--zone-teal);
}

.page-about .about-facts__n {
  font-family: var(--f-mono);
  font-size: 1.05rem;
  color: var(--orange);
  line-height: 1;
}

/* ---------- 四个小组 ---------- */
.page-about .crew-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
  margin-top: 1.6rem;
}

.page-about .crew-card {
  position: relative;
  overflow: hidden;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 1.3rem 1.2rem 1.35rem;
  transition: border-color 0.26s var(--ease), background-color 0.26s var(--ease);
}

.page-about .crew-card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: linear-gradient(90deg, var(--cyan), rgba(51, 224, 212, 0));
  transform: scaleX(0.16);
  transform-origin: left;
  transition: transform 0.3s var(--ease);
}

.page-about .crew-card:hover::before,
.page-about .crew-card:focus-within::before {
  transform: scaleX(1);
}

.page-about .crew-card:hover {
  border-color: rgba(51, 224, 212, 0.4);
  background: #16202a;
}

.page-about .crew-card__idx {
  display: inline-block;
  font-family: var(--f-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  color: var(--orange);
  margin-bottom: 0.5rem;
}

.page-about .crew-card h3 {
  font-family: var(--f-display);
  font-weight: 800;
  font-size: 1.06rem;
  line-height: 1.4;
  margin: 0 0 0.55rem;
  color: var(--paper);
}

.page-about .crew-card p {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .crew-card__more {
  margin-top: 0.85rem;
  padding-top: 0.7rem;
  border-top: 1px dashed var(--line);
  font-family: var(--f-mono);
  font-size: 0.72rem;
  line-height: 1.6;
  color: var(--steel);
  transform: translateY(3px);
  opacity: 0.72;
  transition: transform 0.28s var(--ease), opacity 0.28s var(--ease), color 0.28s var(--ease);
}

.page-about .crew-card:hover .crew-card__more {
  transform: translateY(0);
  opacity: 1;
  color: var(--cyan);
}

/* ---------- 迭代节奏 ---------- */
.page-about .cadence-board {
  margin-top: 1.5rem;
  padding: clamp(1.15rem, 3vw, 1.9rem);
  background: linear-gradient(140deg, var(--zone-indigo) 0%, var(--zone-teal) 100%);
  border: 1px solid var(--line);
  border-radius: 18px;
  clip-path: polygon(0 0, 100% 0, 100% 97%, 0 100%);
}

.page-about .cadence-steps {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.55rem;
  margin: 0 0 1.4rem;
  padding: 0;
}

.page-about .cadence-steps li {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.84rem;
  color: var(--paper);
  padding: 0.55rem 0.7rem;
  background: rgba(11, 15, 18, 0.42);
  border-left: 2px solid rgba(51, 224, 212, 0.45);
}

.page-about .cadence-steps__n {
  font-family: var(--f-mono);
  font-size: 0.76rem;
  color: var(--orange);
  letter-spacing: 0.06em;
}

.page-about .cadence-rows {
  display: grid;
  gap: 0.8rem;
}

.page-about .cadence-row {
  display: grid;
  gap: 0.35rem;
  padding-bottom: 0.8rem;
  border-bottom: 1px solid rgba(157, 180, 194, 0.18);
}

.page-about .cadence-row:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .cadence-row__k {
  font-family: var(--f-mono);
  font-size: 0.76rem;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.page-about .cadence-row p {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.8;
  color: rgba(233, 239, 243, 0.86);
  max-width: 34em;
}

/* ---------- 时间轴节点 ---------- */
.page-about .about-tl-media {
  margin: 1.4rem 0 1.5rem;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--zone-teal);
  clip-path: polygon(0 0, 100% 3%, 100% 100%, 0 97%);
}

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

.page-about .tl {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.7rem;
}

.page-about .tl__item {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.4rem;
  padding: 0.95rem 1rem;
  background: var(--panel);
  border-left: 2px solid var(--steel);
  scroll-margin-top: 5rem;
  transition: border-color 0.26s var(--ease), background-color 0.26s var(--ease);
}

.page-about .tl__item:hover {
  border-left-color: var(--orange);
  background: #182229;
}

.page-about .tl__mark {
  font-family: var(--f-mono);
  font-size: 0.74rem;
  letter-spacing: 0.12em;
  color: var(--cyan);
}

.page-about .tl__body h3 {
  font-family: var(--f-display);
  font-weight: 800;
  font-size: 1rem;
  line-height: 1.4;
  margin: 0 0 0.35rem;
  color: var(--paper);
}

.page-about .tl__body p {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.8;
  color: var(--mist);
  max-width: 34em;
}

/* ---------- 内容来路 ---------- */
.page-about .sources {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.4rem;
  margin-top: 1.2rem;
}

.page-about .sources__note {
  margin: 1.1rem 0 0;
  font-size: 0.84rem;
  line-height: 1.8;
  color: var(--mist);
  padding: 0.85rem 1rem;
  background: var(--zone-wine);
  border-left: 2px solid var(--orange);
  border-radius: 0 10px 10px 0;
}

.page-about .sources__note a {
  color: var(--cyan);
  white-space: nowrap;
}

.page-about .about-src-media {
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--panel);
}

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

/* ---------- 收尾跳转 ---------- */
.page-about .about-next {
  margin-top: clamp(3rem, 7vw, 4.8rem);
  padding-top: 1.6rem;
  border-top: 1px solid var(--line);
}

.page-about .about-next__title {
  font-family: var(--f-display);
  font-weight: 800;
  font-size: clamp(1.2rem, 2.4vw, 1.5rem);
  line-height: 1.3;
  margin: 0 0 1.1rem;
  color: var(--paper);
}

.page-about .about-next__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.7rem;
}

.page-about .about-next__card {
  display: grid;
  gap: 0.25rem;
  padding: 1rem 1.1rem;
  text-decoration: none;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 12px;
  transition: border-color 0.24s var(--ease), transform 0.24s var(--ease), background-color 0.24s var(--ease);
}

.page-about .about-next__card:hover,
.page-about .about-next__card:focus-visible {
  border-color: rgba(51, 224, 212, 0.45);
  background: var(--zone-teal);
  transform: translateY(-2px);
}

.page-about .about-next__n {
  font-family: var(--f-mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--orange);
}

.page-about .about-next__card strong {
  font-size: 0.98rem;
  font-weight: 600;
  color: var(--paper);
}

.page-about .about-next__card em {
  font-style: normal;
  font-size: 0.8rem;
  line-height: 1.6;
  color: var(--mist);
}

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

  .page-about .about-facts {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .cadence-steps {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .page-about .about-next__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 桌面：左轨骨架 + 右侧收窄正文 ---------- */
@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.06fr) minmax(0, 0.94fr);
  }

  .page-about .about-stream::before {
    content: "";
    position: absolute;
    left: 5px;
    top: 0.7rem;
    bottom: 1.2rem;
    width: 2px;
    background: linear-gradient(180deg, var(--cyan) 0%, var(--zone-teal) 32%, var(--zone-indigo) 66%, var(--orange) 100%);
    opacity: 0.85;
    border-radius: 2px;
  }

  .page-about .about-block {
    grid-template-columns: 152px minmax(0, 1fr);
    column-gap: clamp(1.8rem, 3.4vw, 3rem);
  }

  .page-about .about-block__rail {
    position: relative;
    flex-direction: column;
    align-items: flex-start;
    gap: 0.35rem;
    padding-left: 1.9rem;
    padding-top: 0.15rem;
  }

  .page-about .about-block__rail::before {
    content: "";
    position: absolute;
    left: 0;
    top: 0.45rem;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--graphite);
    border: 2px solid var(--steel);
    transition: border-color 0.28s var(--ease), background-color 0.28s var(--ease), box-shadow 0.28s var(--ease);
  }

  .page-about .about-block.is-in .about-block__rail::before {
    border-color: var(--cyan);
    background: var(--cyan);
    box-shadow: 0 0 0 5px rgba(51, 224, 212, 0.13);
  }

  .page-about .about-block__body {
    padding-bottom: 0.5rem;
  }

  .page-about .about-block:nth-child(2) .about-block__body { max-width: 100%; }
  .page-about .about-block:nth-child(3) .about-block__body { max-width: 96%; }
  .page-about .about-block:nth-child(4) .about-block__body { max-width: 92%; }
  .page-about .about-block:nth-child(5) .about-block__body { max-width: 88%; }

  .page-about .crew-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.1rem;
    padding-bottom: 62px;
    align-items: start;
  }

  .page-about .crew-card:nth-child(2) {
    margin-top: 62px;
  }

  .page-about .crew-card:nth-child(4) {
    grid-column: 1 / -1;
  }

  .page-about .cadence-rows {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.2rem;
  }

  .page-about .cadence-row {
    border-bottom: 0;
    padding-bottom: 0;
    border-left: 1px solid rgba(157, 180, 194, 0.24);
    padding-left: 0.9rem;
  }

  .page-about .tl__item {
    grid-template-columns: 108px minmax(0, 1fr);
    gap: 1.2rem;
    align-items: start;
    padding: 1.05rem 1.2rem;
  }

  .page-about .tl__mark {
    padding-top: 0.15rem;
  }

  .page-about .sources {
    grid-template-columns: minmax(0, 1.18fr) minmax(0, 0.82fr);
    align-items: start;
    gap: 2rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .crew-card,
  .page-about .crew-card::before,
  .page-about .crew-card__more,
  .page-about .tl__item,
  .page-about .about-next__card,
  .page-about .about-block__rail::before {
    transition: none;
  }

  .page-about .about-next__card:hover,
  .page-about .about-next__card:focus-visible {
    transform: none;
  }
}
<<<END>>>