.page-about {
  --about-rail: 216px;
  --about-gap: clamp(22px, 3.6vw, 58px);
  position: relative;
  overflow-x: clip;
}

/* ---------------- 首屏 ---------------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(84px, 10vw, 144px) 0 clamp(36px, 5vw, 72px);
  isolation: isolate;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(70% 55% at 88% 2%, rgba(200, 255, 61, 0.12), transparent 62%),
    radial-gradient(80% 62% at 4% 96%, rgba(124, 92, 255, 0.16), transparent 64%),
    linear-gradient(180deg, rgba(11, 27, 43, 0) 44%, rgba(16, 42, 66, 0.7) 100%);
  pointer-events: none;
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1.04fr) minmax(0, 0.96fr);
  gap: var(--about-gap);
  align-items: center;
}

.page-about .about-hero__crumb {
  margin-bottom: clamp(22px, 3vw, 34px);
}

.page-about .about-hero__lead .eyebrow {
  display: block;
  margin-bottom: 14px;
}

.page-about .about-hero__lead .display--xl {
  margin: 0 0 20px;
  max-width: 15ch;
}

.page-about .about-hero__lede {
  max-width: 46ch;
  color: var(--c-muted);
}

.page-about .about-hero__ledger {
  display: flex;
  flex-wrap: wrap;
  gap: clamp(18px, 3vw, 40px);
  margin-top: clamp(26px, 3.6vw, 42px);
  padding-top: clamp(18px, 2.4vw, 26px);
  border-top: 1px solid var(--c-line);
}

.page-about .about-ledger__item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 88px;
}

.page-about .about-ledger__label {
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--c-muted);
}

.page-about .about-hero__figure {
  width: 100%;
}

/* ---------------- 档案区骨架 ---------------- */
.page-about .about-body {
  padding-top: clamp(28px, 4vw, 56px);
}

.page-about .about-archive {
  display: grid;
  grid-template-columns: var(--about-rail) minmax(0, 1fr);
  gap: var(--about-gap);
  align-items: start;
}

.page-about .about-rail {
  position: sticky;
  top: 108px;
  padding-top: 14px;
  border-top: 1px solid var(--c-line);
}

.page-about .about-rail__title {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--c-muted);
}

.page-about .about-rail__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 2px;
}

.page-about .about-rail__link {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 8px 10px 8px 0;
  border-left: 1px solid transparent;
  color: var(--c-muted);
  text-decoration: none;
  font-size: 14px;
  transition: color var(--dur) var(--ease-out), border-color var(--dur) var(--ease-out);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--c-white);
  border-left-color: var(--c-lime);
}

.page-about .about-rail__link:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
  border-radius: var(--radius-sm);
}

.page-about .about-rail__idx {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--c-lime);
  min-width: 34px;
}

.page-about .about-rail__name {
  font-size: 14px;
}

/* ---------------- 资料卡 ---------------- */
.page-about .about-flow {
  display: grid;
  gap: clamp(8px, 1.4vw, 16px);
  min-width: 0;
}

.page-about .about-block {
  padding: clamp(30px, 4.6vw, 54px) 0;
  border-bottom: 1px solid var(--c-line);
}

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

.page-about .about-block .eyebrow {
  display: block;
  margin-bottom: 12px;
}

.page-about .about-block .display--md {
  margin: 0 0 18px;
}

.page-about .about-block__lead {
  max-width: 52ch;
  color: var(--c-muted);
  margin-bottom: clamp(24px, 3.4vw, 38px);
}

.page-about .about-block__body {
  max-width: 58ch;
}

.page-about .about-block__body p + p {
  margin-top: 14px;
}

.page-about .about-block__body a {
  color: var(--c-lime);
  text-decoration: none;
  border-bottom: 1px solid rgba(200, 255, 61, 0.4);
  transition: border-color var(--dur) var(--ease-out);
}

.page-about .about-block__body a:hover {
  border-bottom-color: var(--c-lime);
}

/* ---------------- 时间轴 ---------------- */
.page-about .about-timeline {
  margin: 0 0 clamp(26px, 3.6vw, 44px);
  padding: 4px 0 4px 24px;
  list-style: none;
  border-left: 1px solid var(--c-lime);
  display: grid;
  gap: clamp(22px, 3.2vw, 34px);
}

.page-about .about-timeline li {
  position: relative;
}

.page-about .about-timeline li::before {
  content: "";
  position: absolute;
  left: -29px;
  top: 9px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--c-lime);
  box-shadow: 0 0 0 4px rgba(200, 255, 61, 0.14);
}

.page-about .about-timeline__tag {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--c-orange);
}

.page-about .about-timeline__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: clamp(18px, 2vw, 22px);
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--c-white);
}

.page-about .about-timeline .prose {
  margin: 0;
  color: var(--c-muted);
  max-width: 54ch;
}

.page-about .about-figure {
  width: 100%;
  margin: clamp(26px, 3.6vw, 44px) 0 0;
}

/* ---------------- 团队分工 ---------------- */
.page-about .about-roles {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 262px);
  gap: clamp(26px, 4vw, 56px);
  align-items: center;
}

.page-about .about-roles__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 14px;
}

.page-about .about-roles__item {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  padding: 16px 18px;
  border: 1px solid var(--c-line);
  border-radius: var(--radius-md);
  background: var(--c-deep);
  transition: border-color var(--dur) var(--ease-out), transform var(--dur) var(--ease-out);
}

.page-about .about-roles__item:hover {
  border-color: var(--c-lime);
  transform: translateY(-2px);
}

.page-about .about-roles__dot {
  flex: 0 0 auto;
  width: 10px;
  height: 10px;
  margin-top: 6px;
  border-radius: 50%;
}

.page-about .about-roles__item--lime .about-roles__dot { background: var(--c-lime); }
.page-about .about-roles__item--violet .about-roles__dot { background: var(--c-violet); }
.page-about .about-roles__item--orange .about-roles__dot { background: var(--c-orange); }

.page-about .about-roles__name {
  margin: 0 0 4px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  color: var(--c-white);
  letter-spacing: 0.01em;
}

.page-about .about-roles__desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--c-muted);
}

.page-about .about-donut-wrap {
  margin: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.page-about .about-donut {
  width: 100%;
  max-width: 262px;
  height: auto;
  overflow: visible;
}

.page-about .about-donut__seg {
  transition: opacity var(--dur) var(--ease-out), stroke-width var(--dur) var(--ease-out);
}

.page-about .about-donut__seg--lime { stroke: var(--c-lime); }
.page-about .about-donut__seg--violet { stroke: var(--c-violet); }
.page-about .about-donut__seg--orange { stroke: var(--c-orange); }

.page-about .about-donut:hover .about-donut__seg {
  opacity: 0.4;
}

.page-about .about-donut .about-donut__seg:hover {
  opacity: 1;
  stroke-width: 33;
}

.page-about .about-donut__core {
  font-family: var(--font-mono);
  font-size: 40px;
  font-weight: 700;
  fill: var(--c-white);
}

.page-about .about-donut__core-label {
  font-family: var(--font-body);
  font-size: 13px;
  fill: var(--c-muted);
  letter-spacing: 0.08em;
}

.page-about .about-donut__caption {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--c-muted);
}

/* ---------------- 工序 ---------------- */
.page-about .about-steps {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.page-about .about-steps__item {
  background: var(--c-deep);
  padding: clamp(18px, 2.4vw, 26px);
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-width: 0;
  transition: background var(--dur) var(--ease-out);
}

.page-about .about-steps__item:hover {
  background: var(--c-card);
}

.page-about .about-steps__num {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.14em;
  color: var(--c-teal);
}

.page-about .about-steps__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--c-white);
}

.page-about .about-steps .prose {
  margin: 0;
  color: var(--c-muted);
}

/* ---------------- 长期坚持 ---------------- */
.page-about .about-rules {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(16px, 2.4vw, 26px);
}

.page-about .about-rules__item {
  position: relative;
  padding: 22px 20px 22px 24px;
  border-radius: var(--radius-md);
  background: linear-gradient(180deg, rgba(26, 58, 84, 0.7), rgba(16, 42, 66, 0.45));
  border: 1px solid var(--c-line);
  min-width: 0;
}

.page-about .about-rules__mark {
  position: absolute;
  left: 0;
  top: 22px;
  bottom: 22px;
  width: 3px;
  border-radius: 0 3px 3px 0;
  background: linear-gradient(180deg, var(--c-lime), var(--c-orange));
}

.page-about .about-rules__title {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--c-white);
}

.page-about .about-rules .prose {
  margin: 0;
  color: var(--c-muted);
}

/* ---------------- 合作与收口 ---------------- */
.page-about .about-cta {
  margin-top: clamp(26px, 3.6vw, 40px);
  padding: clamp(22px, 3vw, 32px);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(80% 120% at 100% 0%, rgba(255, 122, 47, 0.14), transparent 62%),
    var(--c-deep);
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  align-items: center;
  justify-content: space-between;
}

.page-about .about-cta__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--c-muted);
  max-width: 42ch;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------------- 响应式 ---------------- */
@media (max-width: 980px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .about-hero__lead .display--xl {
    max-width: 20ch;
  }

  .page-about .about-archive {
    grid-template-columns: minmax(0, 1fr);
    gap: 20px;
  }

  .page-about .about-rail {
    position: static;
    border-top: 1px solid var(--c-line);
    border-bottom: 1px solid var(--c-line);
    padding: 14px 0 4px;
  }

  .page-about .about-rail__title {
    margin-bottom: 10px;
  }

  .page-about .about-rail__list {
    display: flex;
    gap: 6px;
    overflow-x: auto;
    padding-bottom: 12px;
    -webkit-overflow-scrolling: touch;
  }

  .page-about .about-rail__list li {
    flex: 0 0 auto;
  }

  .page-about .about-rail__link {
    padding: 8px 14px;
    border: 1px solid var(--c-line);
    border-radius: var(--radius-pill);
    white-space: nowrap;
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    border-color: var(--c-lime);
  }

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

  .page-about .about-donut-wrap {
    order: -1;
  }

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

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

@media (max-width: 640px) {
  .page-about .about-hero {
    padding-top: 76px;
  }

  .page-about .about-hero__ledger {
    gap: 16px 26px;
  }

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

  .page-about .about-cta {
    flex-direction: column;
    align-items: flex-start;
  }

  .page-about .about-timeline {
    padding-left: 20px;
  }

  .page-about .about-timeline li::before {
    left: -25px;
  }
}
<<<END>>>