.page-about {
  --about-axis-gap: 72px;
  color: var(--text);
}

.page-about .breadcrumb {
  padding-top: clamp(20px, 4vw, 34px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(22px, 5vw, 56px) 0 clamp(28px, 4vw, 44px);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(58% 74% at 90% -12%, rgba(43, 27, 77, 0.78), transparent 68%),
    radial-gradient(52% 64% at 2% 112%, rgba(56, 242, 192, 0.09), transparent 72%);
}

.page-about .about-hero > .wrap {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__title {
  margin: 16px 0 0;
  line-height: 1.03;
  max-width: 18ch;
}

.page-about .about-hero__lede {
  margin-top: 22px;
  max-width: 47ch;
  font-size: clamp(15px, 1.7vw, 17px);
  line-height: 1.82;
  color: rgba(233, 245, 241, 0.76);
}

.page-about .about-kpi {
  list-style: none;
  margin: 34px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  overflow: hidden;
}

.page-about .about-kpi__item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px 18px;
  background: linear-gradient(170deg, rgba(12, 33, 28, 0.95), rgba(6, 18, 15, 0.96));
}

.page-about .about-kpi__num {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-weight: 800;
  font-size: clamp(28px, 3.6vw, 40px);
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--cyan);
}

.page-about .about-kpi__label {
  font-size: 13px;
  line-height: 1.55;
  color: var(--muted);
}

/* ---------- 章节跳转 ---------- */
.page-about .about-jump {
  padding: 2px 0 10px;
}

.page-about .about-jump__list {
  list-style: none;
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 4px;
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

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

.page-about .about-jump__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 44px;
  padding: 0 18px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: rgba(12, 33, 28, 0.62);
  color: var(--text);
  font-size: 14px;
  text-decoration: none;
  white-space: nowrap;
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-jump__link:hover,
.page-about .about-jump__link:focus-visible {
  border-color: var(--cyan);
  background: rgba(56, 242, 192, 0.1);
}

.page-about .about-jump__link:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

.page-about .about-jump__num {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  font-size: 13px;
  color: var(--cyan-soft);
}

/* ---------- 时间线主轴 ---------- */
.page-about .about-story {
  padding-top: clamp(18px, 3vw, 30px);
  padding-bottom: clamp(40px, 7vw, 84px);
}

.page-about .about-track {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  padding-left: 34px;
}

.page-about .about-track::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 12px;
  bottom: 12px;
  width: 1px;
  background: linear-gradient(
    180deg,
    rgba(56, 242, 192, 0.85) 0%,
    rgba(56, 242, 192, 0.22) 44%,
    rgba(56, 242, 192, 0.1) 80%,
    rgba(56, 242, 192, 0) 100%
  );
}

.page-about .chapter {
  position: relative;
  margin-bottom: 30px;
}

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

.page-about .chapter__card {
  position: relative;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: linear-gradient(168deg, var(--ink-2) 0%, rgba(6, 18, 15, 0.98) 100%);
  transition:
    transform var(--dur) var(--ease),
    border-color var(--dur) var(--ease),
    box-shadow var(--dur) var(--ease);
}

.page-about .chapter__card:hover,
.page-about .chapter__card:focus-within {
  transform: translateY(-3px);
  border-color: rgba(56, 242, 192, 0.5);
  box-shadow: 0 20px 44px -30px rgba(0, 0, 0, 0.95);
}

.page-about .chapter__card:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

.page-about .chapter__card::before {
  content: "";
  position: absolute;
  top: 30px;
  left: -26px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  border: 1px solid var(--cyan);
  background: var(--ink);
  transform: translateX(-50%);
  transition: background var(--dur) var(--ease), box-shadow var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .chapter__card:hover::before,
.page-about .chapter__card:focus-within::before {
  background: var(--orange);
  border-color: var(--orange);
  box-shadow: 0 0 0 4px rgba(255, 90, 43, 0.16);
}

.page-about .chapter__idx {
  margin: 0 0 10px;
  color: var(--cyan-soft);
}

.page-about .chapter__title {
  margin: 0;
  font-size: clamp(20px, 2.5vw, 27px);
  line-height: 1.34;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.page-about .chapter__text {
  margin: 14px 0 0;
  max-width: 40ch;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(233, 245, 241, 0.76);
}

.page-about .chapter__more {
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  margin: 0;
  padding-left: 0;
  border-left: 2px solid transparent;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
  transition:
    max-height 0.22s var(--ease),
    opacity 0.18s var(--ease),
    padding 0.22s var(--ease),
    border-color 0.22s var(--ease);
}

.page-about .chapter__card:hover .chapter__more,
.page-about .chapter__card:focus-within .chapter__more {
  max-height: 180px;
  opacity: 1;
  margin-top: 14px;
  padding-left: 12px;
  border-left-color: var(--orange);
}

.page-about .chapter__link {
  margin: 20px 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .chapter__figure {
  margin: 18px 0 0;
}

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

/* ---------- 版本节点 ---------- */
.page-about .about-milestones {
  list-style: none;
  margin: 18px 0 0;
  padding: 0 0 0 16px;
  border-left: 1px solid var(--line);
  display: grid;
  gap: 14px;
}

.page-about .about-milestone {
  position: relative;
  display: grid;
  gap: 4px;
}

.page-about .about-milestone::before {
  content: "";
  position: absolute;
  left: -20px;
  top: 7px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--orange);
}

.page-about .about-milestone__tag {
  font-family: var(--font-num);
  font-size: 12.5px;
  letter-spacing: 0.12em;
  color: var(--cyan-soft);
}

.page-about .about-milestone__text {
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 流程步骤 ---------- */
.page-about .about-steps {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border-radius: var(--r-md);
  overflow: hidden;
}

.page-about .about-step {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 14px;
  padding: 14px 16px;
  background: rgba(12, 33, 28, 0.92);
}

.page-about .about-step__num {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-weight: 800;
  font-size: 20px;
  line-height: 1.2;
  color: var(--cyan);
}

.page-about .about-step__name {
  display: block;
  margin-bottom: 4px;
  font-size: 14px;
  color: var(--text);
}

.page-about .about-step__text {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 团队标签行 ---------- */
.page-about .about-roles {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-role {
  flex: 1 1 190px;
  min-width: 0;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: rgba(22, 51, 44, 0.34);
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-role:hover {
  border-color: rgba(56, 242, 192, 0.45);
  background: rgba(22, 51, 44, 0.64);
}

.page-about .about-role__name {
  display: block;
  margin-bottom: 4px;
  font-size: 14px;
  font-weight: 700;
  color: var(--text);
}

.page-about .about-role__desc {
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 收尾 ---------- */
.page-about .about-close {
  padding-bottom: clamp(48px, 8vw, 88px);
}

.page-about .about-close__inner {
  display: grid;
  gap: 16px;
  padding: clamp(24px, 4vw, 40px);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background:
    linear-gradient(118deg, rgba(43, 27, 77, 0.9) 0%, rgba(74, 21, 38, 0.72) 58%, rgba(6, 18, 15, 0.94) 100%);
}

.page-about .about-close__text {
  margin: 0;
  max-width: 44ch;
  font-size: clamp(16px, 2vw, 20px);
  font-weight: 300;
  line-height: 1.66;
  color: var(--text);
}

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

/* ---------- 窄屏到宽屏 ---------- */
@media (min-width: 700px) {
  .page-about .about-kpi {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__title {
    max-width: 16ch;
  }

  .page-about .about-track {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: var(--about-axis-gap);
    padding-left: 0;
  }

  .page-about .about-track::before {
    left: 50%;
    top: 16px;
    bottom: 16px;
  }

  .page-about .chapter:nth-child(odd) {
    grid-column: 1;
  }

  .page-about .chapter:nth-child(even) {
    grid-column: 2;
  }

  .page-about .chapter {
    margin-bottom: 52px;
  }

  .page-about .chapter__card {
    padding: 30px 32px;
  }

  .page-about .chapter:nth-child(odd) .chapter__card::before {
    left: auto;
    right: calc(var(--about-axis-gap) / -2);
    transform: translateX(50%);
  }

  .page-about .chapter:nth-child(even) .chapter__card::before {
    left: calc(var(--about-axis-gap) / -2);
    right: auto;
    transform: translateX(-50%);
  }

  .page-about .chapter__text {
    max-width: 38ch;
  }

  .page-about .about-close__inner {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: end;
    gap: 24px;
  }

  .page-about .about-close__inner > .eyebrow {
    grid-column: 1 / -1;
  }

  .page-about .about-close__actions {
    justify-content: flex-end;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .chapter__card,
  .page-about .chapter__card::before,
  .page-about .chapter__more,
  .page-about .about-role,
  .page-about .about-jump__link {
    transition: none;
  }

  .page-about .chapter__card:hover,
  .page-about .chapter__card:focus-within {
    transform: none;
  }
}
<<<PAGE_CSS_END>>>