.page-about {
  --about-side: 148px;
  --about-node-w: 78%;
}

/* ---------- 面包屑与首屏 ---------- */
.page-about .breadcrumbs {
  margin: 0 0 18px;
  font-size: 12px;
  letter-spacing: 0.04em;
}

.page-about .about-hero {
  position: relative;
  display: grid;
  gap: 28px;
  padding: 4px 0 40px;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 150px;
  height: 150px;
  background-image: repeating-linear-gradient(
    135deg,
    var(--cyan-06) 0 1px,
    transparent 1px 13px
  );
  pointer-events: none;
}

.page-about .about-hero__title {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(34px, 9vw, 68px);
  line-height: 0.98;
  letter-spacing: -0.02em;
  max-width: 15ch;
}

.page-about .about-hero__lead {
  margin: 16px 0 0;
  max-width: 60ch;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--text-soft);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 22px;
}

.page-about .about-hero__panel {
  position: relative;
  padding: 22px 20px 24px;
  background: var(--panel);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-card);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%);
}

.page-about .about-panel__cap {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-panel__cap::before {
  content: "";
  display: inline-block;
  width: 16px;
  height: 1px;
  margin-right: 8px;
  vertical-align: middle;
  background: var(--cyan);
}

.page-about .about-figures {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px 12px;
  margin-top: 18px;
}

.page-about .about-figure {
  display: block;
  padding-top: 12px;
  border-top: 1px solid var(--line-soft);
}

.page-about .about-figure__value {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(22px, 6vw, 27px);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
  line-height: 1.1;
  color: var(--cyan);
}

.page-about .about-figure__label {
  display: block;
  margin-top: 6px;
  font-size: 12px;
  line-height: 1.5;
  color: var(--muted);
}

.page-about .about-panel__note {
  margin: 20px 0 0;
  padding-top: 14px;
  border-top: 1px solid var(--line-soft);
  font-size: 12px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-chapter {
  padding: 40px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-chapter__inner {
  display: grid;
  gap: 16px;
}

.page-about .about-chapter__side {
  display: flex;
  align-items: baseline;
  gap: 14px;
}

.page-about .about-chapter__no {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.18em;
  color: var(--cyan);
}

.page-about .about-chapter__no::after {
  content: "";
  display: inline-block;
  width: 22px;
  height: 1px;
  margin-left: 10px;
  vertical-align: middle;
  background: var(--cyan-28);
}

.page-about .about-chapter__year {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--muted);
}

.page-about .about-chapter__title {
  margin: 0 0 16px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(25px, 5.4vw, 40px);
  line-height: 1.14;
  letter-spacing: -0.015em;
  color: var(--text);
}

.page-about .about-text p {
  margin: 0 0 14px;
  max-width: 68ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--text-soft);
}

.page-about .about-text--single {
  margin: 0 0 18px;
  max-width: 66ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--text-soft);
}

/* ---------- 要点列表 ---------- */
.page-about .about-points {
  list-style: none;
  display: grid;
  gap: 10px;
  margin: 20px 0 0;
  padding: 0;
}

.page-about .about-points li {
  position: relative;
  padding-left: 20px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .about-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 10px;
  height: 1px;
  background: var(--cyan);
}

/* ---------- 配图 ---------- */
.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--line);
  background: var(--card);
  object-fit: cover;
}

.page-about .about-chapter .about-figure {
  margin: 22px 0 0;
}

.page-about .about-chapter .about-figure figcaption {
  margin-top: 9px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.04em;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 版本时间轴 ---------- */
.page-about .about-timeline {
  list-style: none;
  display: flex;
  gap: 12px;
  margin: 22px 0 0;
  padding: 4px 0 16px;
  overflow-x: auto;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
  overscroll-behavior-x: contain;
}

.page-about .about-node {
  flex: 0 0 var(--about-node-w);
  scroll-snap-align: start;
  padding: 18px 16px 20px;
  background: var(--card);
  border: 1px solid var(--line);
  border-top: 2px solid var(--cyan);
  box-shadow: var(--shadow-card);
}

.page-about .about-node--now {
  border-top-color: var(--orange);
  background: linear-gradient(180deg, rgba(255, 106, 43, 0.08), var(--card) 62%);
}

.page-about .about-node__ver {
  display: inline-block;
  margin-right: 8px;
  padding: 2px 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--ink);
  background: var(--cyan);
}

.page-about .about-node--now .about-node__ver {
  background: var(--orange);
  color: var(--ink);
}

.page-about .about-node__year {
  font-family: var(--font-mono);
  font-size: 12px;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.page-about .about-node__title {
  margin: 12px 0 8px;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -0.01em;
  color: var(--text);
}

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

/* ---------- 团队矩阵 ---------- */
.page-about .about-team {
  display: grid;
  gap: 12px;
  margin-top: 20px;
}

.page-about .about-team__item {
  padding: 18px 16px 20px;
  background: linear-gradient(180deg, rgba(22, 33, 31, 0.94), rgba(10, 14, 13, 0.72));
  border: 1px solid var(--line);
  transition: border-color 220ms var(--ease), transform 220ms var(--ease);
}

.page-about .about-team__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 34px;
  font-variant-numeric: tabular-nums;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--cyan);
}

.page-about .about-team__role {
  margin: 10px 0 8px;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--text);
}

.page-about .about-team__text {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--muted);
  transition: color 220ms var(--ease);
}

/* ---------- 内容准则 ---------- */
.page-about .about-rules {
  margin-top: 18px;
  border-top: 1px solid var(--line-soft);
}

.page-about .about-rule {
  display: grid;
  gap: 6px;
  padding: 20px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-rule__no {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .about-rule__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--text);
}

.page-about .about-rule__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--muted);
}

/* ---------- 手册与合作 ---------- */
.page-about .about-handbook {
  display: grid;
  gap: 22px;
  padding: 22px 18px;
  background: var(--panel);
  border: 1px solid var(--line);
}

.page-about .about-handbook__title {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 700;
  line-height: 1.28;
  letter-spacing: -0.01em;
  color: var(--text);
}

.page-about .about-handbook__text {
  margin: 0 0 12px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--text-soft);
}

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

.page-about .about-handbook__col--stat {
  padding-top: 18px;
  border-top: 1px solid var(--line-soft);
}

.page-about .about-handbook__big {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(44px, 12vw, 62px);
  font-variant-numeric: tabular-nums;
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--orange);
}

.page-about .about-handbook__cap {
  margin: 8px 0 12px;
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

/* ---------- 收尾行动 ---------- */
.page-about .about-cta {
  padding: 44px 0 56px;
}

.page-about .about-cta__inner {
  display: grid;
  gap: 22px;
  padding: 26px 20px;
  border: 1px solid var(--line);
  background: linear-gradient(125deg, rgba(53, 242, 208, 0.07), transparent 46%), var(--panel);
}

.page-about .about-cta__title {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(24px, 5vw, 34px);
  line-height: 1.16;
  letter-spacing: -0.015em;
  color: var(--text);
}

.page-about .about-cta__lead {
  margin: 0;
  max-width: 56ch;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text-soft);
}

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

.page-about .about-cta__link {
  color: var(--cyan);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about {
    --about-node-w: 46%;
  }

  .page-about .about-hero__lead {
    font-size: 16.5px;
  }

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

  .page-about .about-handbook {
    padding: 26px 24px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 48px;
    align-items: start;
    padding: 8px 0 52px;
  }

  .page-about .about-hero__panel {
    margin-top: 6px;
  }

  .page-about .about-chapter {
    padding: 56px 0;
  }

  .page-about .about-chapter__inner {
    grid-template-columns: var(--about-side) minmax(0, 1fr);
    gap: 44px;
    align-items: start;
  }

  .page-about .about-chapter__side {
    flex-direction: column;
    gap: 10px;
    position: sticky;
    top: calc(var(--topbar-h) + 28px);
  }

  .page-about .about-chapter__year {
    font-family: var(--font-display);
    font-size: 32px;
    line-height: 1;
    letter-spacing: -0.01em;
    color: var(--text-soft);
    opacity: 0.5;
  }

  .page-about .about-node {
    flex: 0 0 272px;
    min-height: 196px;
  }

  .page-about .about-timeline {
    gap: 16px;
  }

  .page-about .about-rule {
    grid-template-columns: 56px 216px minmax(0, 1fr);
    gap: 26px;
    align-items: start;
    padding: 24px 0;
  }

  .page-about .about-rule__no {
    padding-top: 4px;
  }

  .page-about .about-handbook {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 40px;
    padding: 30px 28px;
  }

  .page-about .about-handbook__col--stat {
    padding-top: 0;
    padding-left: 32px;
    border-top: 0;
    border-left: 1px solid var(--line-soft);
  }

  .page-about .about-cta__inner {
    grid-template-columns: minmax(0, 6fr) minmax(0, 6fr);
    align-items: center;
    gap: 36px;
    padding: 34px 32px;
  }

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

@media (min-width: 1024px) {
  .page-about .about-team {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-team__item:hover {
    border-color: var(--cyan-28);
    transform: translateY(-3px);
  }

  .page-about .about-team__item:hover .about-team__text {
    color: var(--text-soft);
  }

  .page-about .about-figures {
    gap: 22px 16px;
  }
}

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

  .page-about .about-team__item:hover {
    transform: none;
  }
}