.page-about {
  --about-measure: 68ch;
  --about-radius: 0;
  background-color: var(--night);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.9;
  padding-bottom: clamp(48px, 7vw, 96px);
}

.page-about .shell {
  padding-top: clamp(18px, 3vw, 32px);
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb {
  margin-bottom: clamp(20px, 3vw, 34px);
}

.page-about .breadcrumb ol {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--text-dim);
}

.page-about .breadcrumb li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--moss);
}

.page-about .breadcrumb a {
  color: var(--steel);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 160ms var(--ease), border-color 160ms var(--ease);
}

.page-about .breadcrumb a:hover,
.page-about .breadcrumb a:focus-visible {
  color: var(--mint);
  border-bottom-color: var(--mint);
}

.page-about .breadcrumb [aria-current="page"] {
  color: var(--cream);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-bottom: clamp(28px, 4vw, 48px);
  border-bottom: 1px solid var(--line);
  position: relative;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 88px;
  height: 3px;
  background: var(--brick);
}

.page-about .about-hero h1 {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(30px, 5.4vw, 58px);
  line-height: 1.12;
  letter-spacing: 0.01em;
  color: var(--cream);
  max-width: 18ch;
}

.page-about .about-hero__lead {
  margin: clamp(16px, 2.4vw, 24px) 0 0;
  max-width: var(--about-measure);
  font-size: clamp(16px, 1.7vw, 19px);
  line-height: 1.9;
  color: var(--text);
}

.page-about .about-hero__stamp {
  margin: clamp(18px, 2.4vw, 26px) 0 0;
  padding-top: 14px;
  border-top: 1px dashed var(--line);
  font-size: 12px;
  color: var(--steel);
}

/* ---------- 主栅格 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 3.4vw, 56px);
  align-items: start;
  padding-top: clamp(32px, 5vw, 64px);
}

.page-about .about-article {
  min-width: 0;
}

.page-about .about-section {
  scroll-margin-top: 120px;
  margin-bottom: clamp(44px, 6.5vw, 84px);
}

.page-about .section-kicker {
  margin: 0 0 6px;
  font-size: 11px;
  color: var(--amber);
}

.page-about .about-section h2 {
  margin: 0 0 clamp(16px, 2.2vw, 22px);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(23px, 3.2vw, 34px);
  line-height: 1.25;
  letter-spacing: 0.01em;
  color: var(--cream);
  max-width: 22ch;
}

.page-about .about-prose p,
.page-about .team-intro p,
.page-about .rules-intro {
  margin: 0 0 1.15em;
  max-width: var(--about-measure);
  font-size: 17px;
  line-height: 1.95;
}

.page-about .about-prose p:last-child,
.page-about .team-intro p:last-child {
  margin-bottom: 0;
}

/* ---------- 引文横条 ---------- */
.page-about .quote-band {
  margin: clamp(36px, 5.4vw, 64px) 0;
  padding: clamp(22px, 3vw, 36px) clamp(20px, 3vw, 40px);
  background: var(--cream);
  color: var(--carbon);
  border-left: 5px solid var(--brick);
  display: grid;
  gap: 12px;
  position: relative;
}

.page-about .quote-band::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: linear-gradient(90deg, rgba(26, 21, 18, 0.06) 1px, transparent 1px);
  background-size: 42px 100%;
  pointer-events: none;
}

.page-about .quote-band p {
  position: relative;
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(20px, 2.8vw, 31px);
  line-height: 1.35;
  letter-spacing: 0.01em;
  color: var(--carbon);
}

.page-about .quote-band .mono {
  position: relative;
  font-size: 11px;
  color: #6E6255;
}

/* ---------- 记录方法 ---------- */
.page-about .record-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3vw, 38px);
  align-items: start;
}

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

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

.page-about .about-figure figcaption {
  margin-top: 10px;
  padding-left: 12px;
  border-left: 2px solid var(--brick);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  line-height: 1.7;
  color: var(--text-dim);
}

.page-about .flow-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .flow-step {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 16px;
  padding-bottom: 24px;
  position: relative;
}

.page-about .flow-step::before {
  content: "";
  position: absolute;
  left: 21px;
  top: 44px;
  bottom: 4px;
  border-left: 1px dashed var(--moss);
}

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

.page-about .flow-step:last-child::before {
  display: none;
}

.page-about .flow-step__num {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  background: var(--surface);
  border: 1px solid var(--line-strong);
  font-size: 12px;
  color: var(--live);
}

.page-about .flow-step__title {
  margin: 8px 0 4px;
  font-size: 17px;
  font-weight: 600;
  line-height: 1.5;
  color: var(--cream);
}

.page-about .flow-step__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.9;
  color: var(--text-dim);
}

.page-about .record-extra {
  margin: clamp(24px, 3vw, 32px) 0 0;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  max-width: var(--about-measure);
  font-size: 15px;
  line-height: 1.9;
  color: var(--text-dim);
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3vw, 38px);
  align-items: start;
  margin-bottom: clamp(26px, 3.4vw, 40px);
}

.page-about .about-figure--portrait img {
  aspect-ratio: 4 / 5;
}

.page-about .role-strip {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 3px;
  margin-bottom: clamp(22px, 3vw, 32px);
}

.page-about .role-block {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding: 16px 18px;
  background: var(--surface);
  border-top: 3px solid var(--moss);
  min-height: 78px;
}

.page-about .role-block--core {
  background: var(--grass);
  border-top-color: var(--live);
}

.page-about .role-name {
  font-size: 12px;
  color: var(--text);
}

.page-about .role-count {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 28px;
  line-height: 1;
  color: var(--cream);
}

.page-about .role-block--core .role-count {
  color: var(--live);
}

.page-about .role-notes {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
}

.page-about .role-notes li {
  padding-left: 14px;
  border-left: 1px solid var(--line-strong);
}

.page-about .role-notes .mono {
  display: block;
  margin-bottom: 6px;
  font-size: 11px;
  color: var(--mint);
}

.page-about .role-notes p {
  margin: 0;
  font-size: 15px;
  line-height: 1.9;
  color: var(--text-dim);
}

/* ---------- 发展历程 ---------- */
.page-about .milestone-banner {
  margin: 0 0 clamp(26px, 3.4vw, 40px);
  position: relative;
  overflow: hidden;
  border-top: 1px solid var(--line-strong);
  border-bottom: 1px solid var(--line-strong);
}

.page-about .milestone-banner img {
  display: block;
  width: 100%;
  height: clamp(130px, 22vw, 250px);
  object-fit: cover;
  opacity: 0.62;
}

.page-about .milestones {
  list-style: none;
  margin: 0;
  padding: 0 0 0 34px;
  position: relative;
}

.page-about .milestones::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 12px;
  bottom: 18px;
  width: 1px;
  background: var(--moss);
}

.page-about .milestone {
  position: relative;
  padding-bottom: clamp(24px, 3vw, 34px);
}

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

.page-about .milestone::before {
  content: "";
  position: absolute;
  left: -34px;
  top: 8px;
  width: 13px;
  height: 13px;
  background: var(--amber);
  transition: transform 200ms var(--ease), box-shadow 200ms var(--ease);
}

.page-about .milestone::after {
  content: "";
  position: absolute;
  left: 0;
  top: -6px;
  bottom: 18px;
  width: 240px;
  max-width: 100%;
  background: linear-gradient(90deg, rgba(200, 255, 61, 0.055), transparent 78%);
  opacity: 0;
  transition: opacity 220ms var(--ease);
  pointer-events: none;
}

.page-about .milestone:hover::before,
.page-about .milestone:focus-within::before {
  transform: scale(1.35);
  box-shadow: 0 0 0 4px rgba(255, 165, 31, 0.16);
}

.page-about .milestone:hover::after,
.page-about .milestone:focus-within::after {
  opacity: 1;
}

.page-about .milestone-year {
  display: block;
  font-size: 13px;
  color: var(--live);
}

.page-about .milestone-title {
  margin: 4px 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(19px, 2.3vw, 24px);
  line-height: 1.35;
  color: var(--cream);
}

.page-about .milestone-text {
  margin: 0;
  max-width: var(--about-measure);
  font-size: 16px;
  line-height: 1.9;
  color: var(--text);
}

.page-about .milestone-detail {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 240ms var(--ease);
}

.page-about .milestone:hover .milestone-detail,
.page-about .milestone:focus-within .milestone-detail {
  grid-template-rows: 1fr;
}

.page-about .milestone-detail > p {
  overflow: hidden;
  margin: 0;
  max-width: var(--about-measure);
  font-size: 14px;
  line-height: 1.85;
  color: var(--steel);
}

.page-about .milestone:hover .milestone-detail > p,
.page-about .milestone:focus-within .milestone-detail > p {
  margin-top: 10px;
  padding-left: 12px;
  border-left: 2px solid var(--brick);
}

/* ---------- 记录规矩 ---------- */
.page-about .rules-intro {
  margin-bottom: clamp(22px, 3vw, 30px);
  color: var(--text-dim);
}

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

.page-about .rules-list li {
  padding: 18px 20px;
  background: var(--grass);
  border-left: 3px solid transparent;
  transition: border-color 180ms var(--ease), background-color 180ms var(--ease);
}

.page-about .rules-list li:hover {
  border-left-color: var(--amber);
  background: var(--grass);
}

.page-about .rules-list .mono {
  display: block;
  margin-bottom: 8px;
  font-size: 11px;
  color: var(--amber);
}

.page-about .rules-list p {
  margin: 0;
  max-width: var(--about-measure);
  font-size: 15px;
  line-height: 1.9;
  color: var(--text);
}

/* ---------- 下一步 ---------- */
.page-about .about-next {
  margin-top: clamp(40px, 6vw, 72px);
  padding-top: clamp(26px, 3.6vw, 42px);
  border-top: 1px solid var(--line-strong);
}

.page-about .about-next h2 {
  margin: 6px 0 clamp(20px, 2.6vw, 28px);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(22px, 3vw, 30px);
  color: var(--cream);
}

.page-about .next-links {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 2px;
}

.page-about .next-link {
  display: block;
  padding: 18px 20px;
  background: var(--surface);
  color: inherit;
  text-decoration: none;
  border-left: 3px solid var(--line-strong);
  transition: border-color 180ms var(--ease), background-color 180ms var(--ease);
}

.page-about .next-link:hover,
.page-about .next-link:focus-visible {
  border-left-color: var(--live);
  background: var(--grass);
}

.page-about .next-link:focus-visible {
  outline: 2px solid var(--live);
  outline-offset: 2px;
}

.page-about .next-link .mono {
  display: block;
  margin-bottom: 6px;
  font-size: 11px;
  color: var(--live);
}

.page-about .next-link p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-dim);
}

/* ---------- 章节索引 ---------- */
.page-about .chapter-index {
  min-width: 0;
}

.page-about .chapter-index > .mono {
  display: none;
  font-size: 11px;
  color: var(--steel);
}

.page-about .chapter-index ol {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  scrollbar-width: thin;
  padding-bottom: 6px;
}

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

.page-about .chapter-index a {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border: 1px solid var(--line-strong);
  font-size: 13px;
  color: var(--text-dim);
  text-decoration: none;
  white-space: nowrap;
  transition: color 160ms var(--ease), border-color 160ms var(--ease), background-color 160ms var(--ease);
}

.page-about .chapter-index a:hover,
.page-about .chapter-index a:focus-visible {
  color: var(--night);
  background: var(--live);
  border-color: var(--live);
}

.page-about .chapter-index a:focus-visible {
  outline: 2px solid var(--live);
  outline-offset: 2px;
}

.page-about .chapter-index a .mono {
  font-size: 10px;
  color: var(--amber);
}

.page-about .chapter-index a:hover .mono,
.page-about .chapter-index a:focus-visible .mono {
  color: var(--carbon);
}

/* ---------- 响应式 ---------- */
@media (max-width: 999px) {
  .page-about .chapter-index {
    order: -1;
  }
}

@media (min-width: 760px) {
  .page-about .role-strip {
    grid-template-columns: 10fr 5fr 3fr 2fr;
  }

  .page-about .role-block {
    flex-direction: column;
    align-items: flex-start;
    justify-content: space-between;
    gap: 18px;
    padding: 20px 18px;
    min-height: 132px;
  }

  .page-about .role-name {
    font-size: 11px;
    line-height: 1.6;
    color: var(--text-dim);
  }

  .page-about .role-block--core .role-name {
    color: var(--text);
  }

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

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

@media (min-width: 860px) {
  .page-about .record-grid {
    grid-template-columns: minmax(0, 0.86fr) minmax(0, 1.14fr);
  }

  .page-about .about-figure--sticky {
    position: sticky;
    top: 108px;
  }

  .page-about .team-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 300px);
  }

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

@media (min-width: 1000px) {
  .page-about .about-layout {
    grid-template-columns: minmax(0, 1fr) 208px;
  }

  .page-about .chapter-index {
    position: sticky;
    top: 108px;
    order: 0;
  }

  .page-about .chapter-index > .mono {
    display: block;
    margin-bottom: 12px;
  }

  .page-about .chapter-index ol {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .chapter-index a {
    border: 0;
    border-bottom: 1px solid var(--line);
    padding: 9px 0;
    font-size: 14px;
    white-space: normal;
  }

  .page-about .chapter-index li:first-child a {
    border-top: 1px solid var(--line);
  }

  .page-about .chapter-index a:hover,
  .page-about .chapter-index a:focus-visible {
    background: transparent;
    color: var(--live);
    border-color: var(--line-strong);
  }

  .page-about .chapter-index a:hover .mono,
  .page-about .chapter-index a:focus-visible .mono {
    color: var(--amber);
  }
}

@media (hover: none) {
  .page-about .milestone-detail {
    grid-template-rows: 1fr;
  }

  .page-about .milestone-detail > p {
    margin-top: 10px;
    padding-left: 12px;
    border-left: 2px solid var(--brick);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .milestone::before,
  .page-about .milestone::after,
  .page-about .milestone-detail,
  .page-about .chapter-index a,
  .page-about .next-link,
  .page-about .rules-list li {
    transition: none;
  }

  .page-about .milestone:hover::before,
  .page-about .milestone:focus-within::before {
    transform: none;
  }
}