.page-about {
  --about-rail: 108px;
  --about-line: #1F4239;
  --about-ink: #C3D8D1;
  background: var(--ink-900);
  color: var(--paper);
  padding-bottom: clamp(40px, 8vw, 96px);
}

.page-about .crumbs {
  margin-top: clamp(14px, 3vw, 26px);
}

.page-about .prose {
  max-width: 44em;
  margin: 0 0 14px;
  color: var(--about-ink);
  font-size: 15.5px;
  line-height: 1.8;
}

.page-about .section-head__title {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: var(--step-2);
  line-height: 1.14;
  letter-spacing: -0.01em;
  margin: 0 0 14px;
  color: var(--paper);
  max-width: 22em;
}

.page-about .note {
  display: block;
  margin: 16px 0 0;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: clamp(20px, 3.4vw, 40px);
  padding-block: clamp(22px, 5vw, 54px) clamp(32px, 6vw, 76px);
}

.page-about .about-hero__lead {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.page-about .eyebrow {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cyan);
  margin: 0;
}

.page-about .about-hero h1 {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: var(--step-3);
  line-height: 1.04;
  letter-spacing: -0.02em;
  margin: 0;
  max-width: 15em;
  color: var(--paper);
}

.page-about .about-hero .lede {
  margin: 0;
  max-width: 36em;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--about-ink);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px 10px;
  margin-top: 8px;
}

.page-about .about-hero__stats .stat {
  border-left: 1px solid var(--about-line);
  padding-left: 12px;
}

.page-about .about-hero__stats .stat__value {
  display: block;
  font-family: var(--font-mono);
  font-size: 26px;
  line-height: 1.1;
  letter-spacing: 0.02em;
  color: var(--amber);
}

.page-about .about-hero__stats .stat--cyan .stat__value {
  color: var(--cyan);
}

.page-about .about-hero__stats .stat--violet .stat__value {
  color: var(--violet-ink);
}

.page-about .about-hero__stats .stat__label {
  display: block;
  margin-top: 4px;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--muted);
}

.page-about .about-hero__media {
  margin: 0;
}

.page-about .about-hero__media img,
.page-about .about-chapter__fig img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--about-line);
  border-radius: 2px;
  object-fit: cover;
}

.page-about .about-hero__media .media__caption,
.page-about .about-chapter__fig .media__caption {
  margin-top: 8px;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--muted);
}

/* ---------- 章节骨架：左侧纵轴 + 右侧内容 ---------- */
.page-about .about-chapter {
  position: relative;
  display: grid;
  gap: clamp(14px, 2.4vw, 26px);
  padding-block: clamp(34px, 6vw, 78px);
  border-top: 1px solid var(--about-line);
}

.page-about .about-chapter__rail {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.page-about .about-chapter__num {
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 700;
  letter-spacing: 0.06em;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-chapter__tag {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-chapter__fig {
  margin: 4px 0 0;
}

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

/* ---------- 团队分工 ---------- */
.page-about .about-team {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.page-about .about-team__card {
  background: var(--label);
  color: #0A1A15;
  border: 1px solid #D6CCB0;
  border-radius: 2px;
  padding: 14px 16px 16px;
  box-shadow: 4px 4px 0 rgba(47, 240, 200, 0.16);
}

.page-about .about-team__card:nth-child(2) {
  box-shadow: 4px 4px 0 rgba(155, 108, 255, 0.22);
}

.page-about .about-team__card:nth-child(3) {
  box-shadow: 4px 4px 0 rgba(242, 178, 60, 0.24);
}

.page-about .about-team__card:nth-child(4) {
  box-shadow: 4px 4px 0 rgba(47, 240, 200, 0.16);
}

.page-about .about-team__badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: #0A1A15;
  border-bottom: 1px solid rgba(10, 26, 21, 0.35);
  padding-bottom: 4px;
  margin-bottom: 9px;
}

.page-about .about-team__card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: #16261F;
}

/* ---------- 归档流程 ---------- */
.page-about .about-flow {
  list-style: none;
  margin: 20px 0 0;
  padding: 0;
  border-top: 1px dashed var(--about-line);
}

.page-about .about-flow__step {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  gap: 12px;
  padding: 16px 0;
  border-bottom: 1px dashed var(--about-line);
  transition: background var(--dur) var(--ease);
}

.page-about .about-flow__step:hover,
.page-about .about-flow__step:focus-within {
  background: var(--ink-800);
}

.page-about .about-flow__num {
  font-family: var(--font-mono);
  font-size: 20px;
  letter-spacing: 0.06em;
  line-height: 1.3;
  color: var(--amber);
}

.page-about .about-flow__title {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: var(--step-1);
  margin: 0 0 6px;
  color: var(--paper);
}

.page-about .about-flow__step p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--about-ink);
}

/* ---------- 更新节奏（横向滑动） ---------- */
.page-about .about-cadence {
  list-style: none;
  margin: 18px 0 0;
  padding: 0 0 12px;
  display: flex;
  gap: 12px;
  overflow-x: auto;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-cadence::-webkit-scrollbar {
  height: 4px;
}

.page-about .about-cadence::-webkit-scrollbar-thumb {
  background: var(--about-line);
  border-radius: 2px;
}

.page-about .about-cadence__card {
  flex: 0 0 auto;
  width: min(76vw, 268px);
  scroll-snap-align: start;
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 16px;
  border: 1px solid var(--about-line);
  border-radius: 2px;
  background: var(--ink-800);
}

.page-about .about-cadence__card .tag {
  align-self: flex-start;
}

.page-about .about-cadence__freq {
  margin: 2px 0 0;
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.08em;
  color: var(--amber);
}

.page-about .about-cadence__card p:last-child {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--muted);
}

/* ---------- 订阅服务 ---------- */
.page-about .about-sub {
  list-style: none;
  margin: 18px 0 20px;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-line);
  border: 1px solid var(--about-line);
}

.page-about .about-sub__item {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  align-items: center;
  gap: 12px;
  padding: 13px 14px;
  background: var(--ink-800);
  font-size: 14.5px;
  line-height: 1.65;
  color: var(--paper);
}

.page-about .about-sub__key {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.14em;
  color: var(--violet-ink);
}

/* ---------- 发展节点时间轴 ---------- */
.page-about .about-timeline {
  list-style: none;
  position: relative;
  margin: 22px 0 0;
  padding: 0 0 0 30px;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--about-line);
}

.page-about .about-timeline__node {
  position: relative;
  padding-bottom: clamp(20px, 3.6vw, 34px);
}

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

.page-about .about-timeline__node::before {
  content: "";
  position: absolute;
  left: -30px;
  top: 7px;
  width: 9px;
  height: 9px;
  background: var(--ink-900);
  border: 1px solid var(--cyan);
  transform: rotate(45deg);
}

.page-about .about-timeline__year {
  display: block;
  font-family: var(--font-mono);
  font-size: 19px;
  letter-spacing: 0.12em;
  color: var(--cyan);
  margin-bottom: 4px;
}

.page-about .about-timeline__title {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 17px;
  margin: 0 0 5px;
  color: var(--paper);
}

.page-about .about-timeline__node p {
  margin: 0;
  max-width: 40em;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--about-ink);
}

/* ---------- 收尾导航 ---------- */
.page-about .about-outro {
  margin-top: clamp(28px, 5vw, 56px);
  padding: clamp(22px, 4vw, 44px);
  border: 1px solid var(--about-line);
  background: linear-gradient(135deg, #0B1F1A 0%, #06120F 66%);
  display: grid;
  gap: 18px;
}

.page-about .about-outro__title {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: var(--step-1);
  margin: 0;
  color: var(--paper);
}

.page-about .about-outro__links {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}

.page-about .about-outro__link {
  display: block;
  padding: 13px 16px;
  border: 1px solid var(--about-line);
  border-left: 2px solid var(--cyan);
  background: rgba(19, 44, 37, 0.6);
  color: var(--paper);
  font-size: 15px;
  line-height: 1.5;
  text-decoration: none;
  transition: background var(--dur) var(--ease), transform var(--dur) var(--ease), border-left-color var(--dur) var(--ease);
}

.page-about .about-outro__link span {
  display: block;
  margin-top: 4px;
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.page-about .about-outro__link:hover,
.page-about .about-outro__link:focus-visible {
  background: rgba(47, 240, 200, 0.09);
  border-left-color: var(--cyan-soft);
  transform: translateX(3px);
}

.page-about .about-outro__back {
  margin: 4px 0 0;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-team {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: end;
  }

  .page-about .about-hero__media {
    align-self: end;
  }

  .page-about .about-chapter {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    column-gap: clamp(20px, 3vw, 46px);
    padding-block: clamp(44px, 6vw, 88px);
  }

  .page-about .about-chapter__rail {
    display: block;
    padding-top: 6px;
  }

  .page-about .about-chapter__rail::after {
    content: "";
    position: absolute;
    left: 5px;
    top: 44px;
    bottom: calc(-1 * clamp(44px, 6vw, 88px));
    width: 1px;
    background: linear-gradient(180deg, var(--about-line) 0%, rgba(31, 66, 57, 0) 100%);
  }

  .page-about .about-chapter__tag {
    display: block;
    margin-top: 10px;
  }

  .page-about .about-flow__step {
    grid-template-columns: 72px minmax(0, 1fr);
    padding: 20px 10px;
  }

  .page-about .about-team {
    gap: 14px;
  }

  .page-about .about-cadence__card {
    width: 268px;
  }
}

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

  .page-about .about-outro__link:hover,
  .page-about .about-outro__link:focus-visible {
    transform: none;
  }

  .page-about .about-cadence {
    scroll-snap-type: none;
  }
}