.page-about {
  padding: 18px var(--gutter) 88px;
  min-width: 0;
}

.page-about > * {
  min-width: 0;
}

/* ---------- 面包屑 ---------- */
.page-about .crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--muted);
}

.page-about .crumbs a {
  color: var(--muted);
  text-decoration: none;
  transition: color 160ms var(--ease);
}

.page-about .crumbs a:hover,
.page-about .crumbs a:focus-visible {
  color: var(--cyan);
}

.page-about .crumbs__sep {
  color: var(--line);
}

/* ---------- 刊头 ---------- */
.page-about .about-masthead {
  position: relative;
  display: grid;
  gap: 14px;
  padding: 30px 0 32px;
  border-bottom: 1px solid var(--line);
}

.page-about .about-masthead::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 132px;
  height: 2px;
  background: linear-gradient(90deg, var(--cyan) 0%, var(--cyan-deep) 100%);
}

.page-about .about-masthead .display {
  max-width: 20ch;
  margin: 0;
}

.page-about .about-masthead .lede {
  max-width: 62ch;
  font-size: 16px;
  margin: 0;
}

.page-about .about-masthead .kicker {
  margin: 0;
  color: var(--cyan);
}

/* ---------- 关键数字条 ---------- */
.page-about .about-stats {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-stat {
  background: var(--panel);
  padding: 18px 16px 20px;
  display: grid;
  gap: 8px;
  align-content: start;
  min-width: 0;
}

.page-about .about-stat__num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 32px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--cyan);
}

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

/* ---------- 双栏骨架 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
  margin-top: 44px;
}

.page-about .about-rail {
  border-top: 2px solid var(--cyan);
  padding-top: 12px;
  min-width: 0;
}

.page-about .about-rail__title {
  margin: 0 0 10px;
  color: var(--muted);
}

.page-about .about-index {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 2px;
}

.page-about .about-index__link {
  display: grid;
  grid-template-columns: 26px minmax(0, 1fr);
  gap: 8px;
  align-items: baseline;
  padding: 8px 6px;
  border-left: 2px solid transparent;
  color: var(--muted);
  text-decoration: none;
  font-size: 14px;
  line-height: 1.45;
  transition: color 160ms var(--ease), border-color 160ms var(--ease),
    background-color 160ms var(--ease);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--ink);
  border-left-color: var(--cyan);
  background: var(--panel);
}

.page-about .about-index__idx {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--cyan);
}

/* ---------- 章节 ---------- */
.page-about .about-flow {
  display: grid;
  min-width: 0;
}

.page-about .about-chapter {
  min-width: 0;
  padding-bottom: 46px;
  border-bottom: 1px solid var(--line);
  scroll-margin-top: 92px;
}

.page-about .about-chapter + .about-chapter {
  padding-top: 46px;
}

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

.page-about .chapter-no {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .chapter-no::after {
  content: "";
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--line) 0%, transparent 100%);
}

.page-about .about-chapter .section-title {
  margin: 0 0 16px;
  max-width: 26ch;
}

.page-about .about-chapter p {
  margin: 0 0 14px;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--ink);
  max-width: 74ch;
}

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

.page-about .about-chapter .note {
  font-family: var(--font-serif);
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--muted);
  max-width: 70ch;
  padding-left: 14px;
  border-left: 1px solid var(--line);
}

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

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

/* ---------- 团队 ---------- */
.page-about .staff-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: 24px;
}

.page-about .staff-card {
  position: relative;
  min-width: 0;
  background: var(--panel);
  border: 1px solid var(--line);
  padding: 18px 18px 20px;
  clip-path: polygon(
    0 0,
    100% 0,
    100% calc(100% - var(--cut)),
    calc(100% - var(--cut)) 100%,
    0 100%
  );
  transition: background-color 180ms var(--ease), transform 180ms var(--ease);
}

.page-about .staff-card:hover {
  background: var(--layer);
  transform: translateY(-2px);
}

.page-about .staff-card__num {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 36px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--ink);
}

.page-about .staff-card__unit {
  font-family: var(--font-display);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0;
  color: var(--cyan);
  margin-left: 5px;
}

.page-about .staff-card__title {
  margin: 10px 0 6px;
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .staff-card__desc {
  margin: 0 0 12px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .staff-card__duty {
  list-style: none;
  margin: 0;
  padding: 10px 0 0;
  border-top: 1px solid var(--line);
  display: grid;
  gap: 5px;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .staff-card__duty li::before {
  content: "—";
  color: var(--cyan-deep);
  margin-right: 6px;
}

/* ---------- 版本演进 ---------- */
.page-about .version-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  margin-top: 22px;
}

.page-about .version-layout .media {
  margin: 0;
}

.page-about .version-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
  min-width: 0;
}

.page-about .version {
  min-width: 0;
  background: var(--panel);
  border: 1px solid var(--line);
  border-left: 3px solid var(--cyan-deep);
  padding: 16px 18px 18px;
  transition: border-left-color 180ms var(--ease), background-color 180ms var(--ease);
}

.page-about .version:hover {
  border-left-color: var(--cyan);
  background: var(--layer);
}

.page-about .version__no {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--cyan);
}

.page-about .version .card-title {
  margin: 0 0 6px;
}

.page-about .version p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--muted);
  max-width: none;
}

/* ---------- 数据源流向 ---------- */
.page-about .source-map {
  margin: 24px 0;
  padding: 18px 16px 12px;
  background: var(--panel);
  border: 1px solid var(--line);
  min-width: 0;
}

.page-about .source-map svg {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .source-map .src-nodes circle {
  animation: about-node-in 420ms var(--ease) both;
}

.page-about .source-map .src-nodes circle:nth-child(1) { animation-delay: 30ms; }
.page-about .source-map .src-nodes circle:nth-child(2) { animation-delay: 60ms; }
.page-about .source-map .src-nodes circle:nth-child(3) { animation-delay: 90ms; }
.page-about .source-map .src-nodes circle:nth-child(4) { animation-delay: 120ms; }
.page-about .source-map .src-nodes circle:nth-child(5) { animation-delay: 150ms; }
.page-about .source-map .src-nodes circle:nth-child(6) { animation-delay: 180ms; }
.page-about .source-map .src-nodes circle:nth-child(7) { animation-delay: 210ms; }
.page-about .source-map .src-nodes circle:nth-child(8) { animation-delay: 240ms; }
.page-about .source-map .src-nodes circle:nth-child(9) { animation-delay: 270ms; }
.page-about .source-map .src-nodes circle:nth-child(10) { animation-delay: 300ms; }
.page-about .source-map .src-nodes circle:nth-child(11) { animation-delay: 330ms; }
.page-about .source-map .src-nodes circle:nth-child(12) { animation-delay: 360ms; }

@keyframes about-node-in {
  from {
    opacity: 0;
    transform: translateY(-6px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.page-about .source-map .media__cap {
  margin: 10px 0 0;
  font-family: var(--font-serif);
  font-size: 13px;
  color: var(--muted);
}

/* ---------- 覆盖与高峰 ---------- */
.page-about .reach-bar {
  position: relative;
  height: 42px;
  margin: 24px 0 10px;
  border: 1px solid var(--line);
  background: linear-gradient(
    90deg,
    var(--cyan) 0%,
    var(--cyan-deep) 48%,
    var(--layer) 100%
  );
  overflow: hidden;
}

.page-about .reach-bar::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image: linear-gradient(90deg, var(--abyss) 0 2px, transparent 2px);
  background-size: calc(100% / 30) 100%;
}

.page-about .reach-cap {
  margin: 0 0 22px;
  font-family: var(--font-serif);
  font-size: 13.5px;
  color: var(--muted);
  max-width: none;
}

.page-about .reach-cap__num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 20px;
  font-weight: 700;
  color: var(--cyan);
  margin-right: 6px;
}

.page-about .reach-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .reach-list li {
  background: var(--panel);
  padding: 14px 16px;
  display: grid;
  gap: 6px;
  min-width: 0;
}

.page-about .reach-list__key {
  font-family: var(--font-mono);
  font-size: 15px;
  letter-spacing: 0.04em;
  color: var(--cyan);
}

.page-about .reach-list__val {
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .reach-metrics {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.page-about .reach-metrics li {
  border-top: 1px solid var(--line);
  padding-top: 12px;
  display: grid;
  gap: 6px;
  min-width: 0;
}

.page-about .reach-metrics__num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 28px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--ink);
}

.page-about .reach-metrics__unit {
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0;
  color: var(--muted);
  margin-left: 4px;
}

.page-about .reach-metrics__label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 老地方杯 ---------- */
.page-about .cup-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  margin-top: 22px;
}

.page-about .cup-figure {
  margin: 0;
}

.page-about .cup-text p {
  max-width: 68ch;
}

/* ---------- 四件小事 ---------- */
.page-about .practice-list {
  list-style: none;
  margin: 4px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .practice {
  position: relative;
  min-width: 0;
  background: var(--panel);
  border: 1px solid var(--line);
  padding: 18px 18px 20px 20px;
  display: grid;
  gap: 8px;
  align-content: start;
}

.page-about .practice::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: linear-gradient(180deg, var(--cyan) 0%, var(--cyan-deep) 100%);
}

.page-about .practice__no {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--muted);
}

.page-about .practice__title {
  margin: 0;
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .practice p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--muted);
  max-width: none;
}

/* ---------- 下一步 ---------- */
.page-about .about-next {
  margin-top: 52px;
  padding: 28px 22px 30px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-top: 2px solid var(--coral);
  display: grid;
  gap: 12px;
}

.page-about .about-next .kicker {
  margin: 0;
  color: var(--coral);
}

.page-about .about-next .section-title {
  margin: 0;
}

.page-about .about-next__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--muted);
  max-width: 72ch;
}

.page-about .about-next__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 4px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .staff-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

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

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

@media (min-width: 760px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .version-layout {
    grid-template-columns: 260px minmax(0, 1fr);
    gap: 30px;
    align-items: start;
  }

  .page-about .version--1 { width: 78%; }
  .page-about .version--2 { width: 86%; }
  .page-about .version--3 { width: 94%; }
  .page-about .version--4 { width: 100%; }

  .page-about .cup-layout {
    grid-template-columns: minmax(0, 1fr) 340px;
    gap: 28px;
    align-items: start;
  }
}

@media (min-width: 1024px) {
  .page-about .about-body {
    grid-template-columns: 232px minmax(0, 1fr);
    gap: 52px;
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: 88px;
  }

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

  .page-about .about-next {
    padding: 32px 30px 34px;
  }
}

@media (min-width: 1280px) {
  .page-about {
    padding-left: 32px;
    padding-right: 32px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .source-map .src-nodes circle {
    animation: none;
  }

  .page-about .staff-card,
  .page-about .version {
    transition: none;
  }

  .page-about .staff-card:hover {
    transform: none;
  }
}