.page-about .wrap {
  width: 100%;
  max-width: var(--max);
  margin-inline: auto;
  padding-inline: var(--pad);
}

.page-about .breadcrumb {
  padding-top: clamp(20px, 3vw, 34px);
}

/* ---------- 首屏 ---------- */
.page-about .a-hero {
  display: grid;
  gap: 32px;
  padding-block: clamp(20px, 3.5vw, 40px) clamp(44px, 6vw, 80px);
}

@media (min-width: 900px) {
  .page-about .a-hero {
    grid-template-columns: minmax(0, 6fr) minmax(0, 5fr);
    gap: clamp(32px, 5vw, 64px);
    align-items: center;
  }
}

.page-about .a-hero__title {
  font-family: var(--serif);
  font-weight: 900;
  font-size: clamp(2rem, 5.4vw, 3.75rem);
  line-height: 1.14;
  letter-spacing: -0.01em;
  color: var(--paper);
  margin: 14px 0 0;
}

.page-about .a-hero__lede {
  margin-top: 18px;
}

.page-about .a-facts {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 30px 0 0;
  padding: 0;
  background: var(--line);
  border: 1px solid var(--line);
}

@media (min-width: 620px) {
  .page-about .a-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .a-facts li {
  background: var(--ink);
  padding: 16px 14px 14px;
  display: grid;
  gap: 8px;
}

.page-about .a-facts__num {
  font-family: var(--mono);
  font-size: clamp(1.5rem, 3.4vw, 1.95rem);
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--gold);
}

.page-about .a-facts__key {
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  color: var(--muted);
}

.page-about .a-hero__figure {
  position: relative;
  margin: 0;
  padding: 10px;
  border: 1px solid var(--line);
  background: var(--ink-2);
}

.page-about .a-hero__figure::before,
.page-about .a-hero__figure::after {
  content: "";
  position: absolute;
  width: 14px;
  height: 14px;
  border: 1px solid var(--gold);
  pointer-events: none;
}

.page-about .a-hero__figure::before {
  top: -1px;
  left: -1px;
  border-right: 0;
  border-bottom: 0;
}

.page-about .a-hero__figure::after {
  right: -1px;
  bottom: -1px;
  border-top: 0;
  border-left: 0;
}

.page-about .a-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.page-about .a-hero__figure figcaption {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.16em;
  color: var(--muted);
  padding: 10px 4px 2px;
  line-height: 1.7;
}

/* ---------- 主栅格 ---------- */
.page-about .a-grid {
  display: grid;
  gap: clamp(32px, 5vw, 48px);
  padding-bottom: clamp(56px, 9vw, 120px);
}

@media (min-width: 1000px) {
  .page-about .a-grid {
    grid-template-columns: 236px minmax(0, 1fr);
    gap: clamp(40px, 5vw, 76px);
    align-items: start;
  }
}

.page-about .a-aside {
  display: grid;
  gap: 26px;
  align-content: start;
}

@media (min-width: 1000px) {
  .page-about .a-aside {
    position: sticky;
    top: 24px;
    max-height: calc(100vh - 48px);
    overflow-y: auto;
  }
}

.page-about .a-toc__title,
.page-about .a-digest__title {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.28em;
  color: var(--muted);
  margin: 0 0 12px;
}

.page-about .a-toc .toc__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
  border-left: 1px solid var(--line);
}

.page-about .a-toc .toc__link {
  display: block;
  padding: 7px 12px;
  margin-left: -1px;
  border-left: 2px solid transparent;
  color: var(--paper);
  text-decoration: none;
  font-size: 0.875rem;
  line-height: 1.55;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .a-toc .toc__link:hover {
  color: var(--gold-bright);
}

.page-about .a-toc .toc__link.is-active {
  border-left-color: var(--gold);
  color: var(--gold);
}

@media (max-width: 999px) {
  .page-about .a-toc .toc__list {
    display: flex;
    flex-wrap: nowrap;
    overflow-x: auto;
    border-left: 0;
    border-bottom: 1px solid var(--line);
  }

  .page-about .a-toc .toc__link {
    white-space: nowrap;
    margin-left: 0;
    margin-bottom: -1px;
    border-left: 0;
    border-bottom: 2px solid transparent;
  }

  .page-about .a-toc .toc__link.is-active {
    border-bottom-color: var(--gold);
  }
}

.page-about .a-digest {
  border: 1px solid var(--line);
  border-top: 2px solid var(--gold);
  background: var(--ink-2);
  padding: 18px 16px 20px;
}

.page-about .a-digest .a-digest__title {
  color: var(--gold);
  margin-bottom: 10px;
}

.page-about .a-digest p {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .a-marks {
  border: 1px dashed var(--line);
  padding: 16px 16px 18px;
}

.page-about .a-marks ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .a-marks li {
  display: flex;
  gap: 12px;
  align-items: baseline;
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .a-marks .mono {
  flex: 0 0 auto;
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  color: var(--gold);
}

/* ---------- 正文列 ---------- */
.page-about .a-main p {
  font-size: 1rem;
  line-height: 1.85;
  color: var(--paper);
  margin: 0 0 1.1em;
}

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

.page-about .a-section {
  padding-block: clamp(36px, 5vw, 62px);
  border-top: 1px solid var(--line);
}

.page-about .a-section:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .a-section__title {
  font-family: var(--serif);
  font-weight: 900;
  font-size: clamp(1.5rem, 3.6vw, 2.2rem);
  line-height: 1.26;
  letter-spacing: -0.01em;
  color: var(--paper);
  margin: 12px 0 22px;
}

.page-about .a-note {
  font-size: 0.875rem;
  line-height: 1.85;
  color: var(--muted);
  border-left: 2px solid var(--line);
  padding-left: 16px;
  margin: 26px 0 0;
}

/* 开篇双栏 */
.page-about .a-split {
  display: grid;
  gap: 24px;
  margin-top: 4px;
}

@media (min-width: 760px) {
  .page-about .a-split {
    grid-template-columns: minmax(0, 4fr) minmax(0, 7fr);
    gap: clamp(28px, 4vw, 56px);
  }
}

.page-about .a-split__lead {
  font-size: 1.0625rem;
  line-height: 1.8;
  color: var(--paper);
  border-top: 2px solid var(--gold);
  padding-top: 18px;
  margin: 0;
}

/* 收录 / 不收录 */
.page-about .a-yesno {
  display: grid;
  gap: 16px;
  margin: 30px 0 0;
}

@media (min-width: 720px) {
  .page-about .a-yesno {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .a-yesno__col {
  border: 1px solid var(--line);
  background: var(--ink-2);
  padding: 16px 18px 18px;
}

.page-about .a-yesno__col--in {
  border-top: 3px solid var(--jade-l);
}

.page-about .a-yesno__col--out {
  border-top: 3px solid var(--cinnabar-l);
}

.page-about .a-yesno__head {
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.22em;
  margin: 0 0 14px;
}

.page-about .a-yesno__col--in .a-yesno__head {
  color: var(--jade-l);
}

.page-about .a-yesno__col--out .a-yesno__head {
  color: var(--cinnabar-l);
}

.page-about .a-yesno__col ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .a-yesno__col li {
  position: relative;
  padding-left: 18px;
  font-size: 0.9375rem;
  line-height: 1.7;
  color: var(--paper);
}

.page-about .a-yesno__col li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 8px;
  height: 1px;
  background: var(--muted);
}

.page-about .a-yesno__col--in li::before {
  background: var(--jade-l);
}

.page-about .a-yesno__col--out li::before {
  background: var(--cinnabar-l);
}

/* 三组分工 */
.page-about .a-crews {
  margin: 30px 0 0;
  border: 1px solid var(--line);
}

.page-about .a-crew {
  display: grid;
  gap: 10px;
  padding: 20px 18px;
  border-top: 1px solid var(--line);
}

.page-about .a-crew:first-child {
  border-top: 0;
}

@media (min-width: 760px) {
  .page-about .a-crew {
    grid-template-columns: 108px minmax(0, 1fr);
    gap: 24px;
    padding: 24px 26px;
  }
}

.page-about .a-crew__id {
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.page-about .a-crew__id .mono {
  font-family: var(--mono);
  font-size: 1.5rem;
  line-height: 1;
  letter-spacing: 0.04em;
  color: var(--gold);
}

.page-about .a-crew__size {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  color: var(--muted);
  border: 1px solid var(--line);
  padding: 3px 8px;
}

.page-about .a-crew__name {
  font-family: var(--serif);
  font-weight: 900;
  font-size: 1.25rem;
  line-height: 1.4;
  letter-spacing: 0.01em;
  color: var(--paper);
  margin: 0 0 10px;
}

.page-about .a-crew__body p {
  font-size: 0.9375rem;
  line-height: 1.8;
  margin: 0 0 10px;
}

.page-about .a-crew__out {
  font-family: var(--mono);
  font-size: 0.75rem;
  line-height: 1.7;
  letter-spacing: 0.04em;
  color: var(--gold);
  margin: 0;
}

/* 校验步骤 */
.page-about .a-flow {
  margin-top: 28px;
  counter-reset: step;
  border: 1px solid var(--line);
}

.page-about .a-step {
  background: var(--ink-2);
}

.page-about .a-step + .a-step {
  border-top: 1px solid var(--line);
}

.page-about .a-step summary {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding: 15px 18px;
  cursor: pointer;
  list-style: none;
  font-size: 0.9375rem;
  line-height: 1.7;
  color: var(--paper);
  transition: color 0.2s var(--ease);
}

.page-about .a-step summary::-webkit-details-marker {
  display: none;
}

.page-about .a-step summary::before {
  counter-increment: step;
  content: counter(step, decimal-leading-zero);
  flex: 0 0 auto;
  min-width: 22px;
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
  color: var(--gold);
}

.page-about .a-step summary:hover {
  color: var(--gold-bright);
}

.page-about .a-step[open] summary {
  color: var(--gold);
}

.page-about .a-step p {
  margin: 0;
  padding: 0 18px 18px 56px;
  font-size: 0.9375rem;
  line-height: 1.85;
  color: var(--muted);
}

@media (max-width: 560px) {
  .page-about .a-step p {
    padding-left: 18px;
  }
}

/* 图文块 */
.page-about .a-figure {
  margin: 30px 0 0;
  padding: 10px;
  border: 1px solid var(--line);
  background: var(--ink-2);
}

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

.page-about .a-figure--tall img {
  aspect-ratio: 3 / 4;
}

.page-about .a-figure--wide img {
  aspect-ratio: 2 / 1;
}

@media (min-width: 900px) {
  .page-about .a-figure--tall {
    max-width: 400px;
  }
}

.page-about .a-figure figcaption {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  line-height: 1.75;
  color: var(--muted);
  padding: 10px 4px 2px;
}

/* 班次编排台 */
.page-about .a-shifts {
  display: grid;
  gap: 10px;
  margin-top: 28px;
}

.page-about .a-shift {
  border: 1px solid var(--line);
  border-left: 3px solid var(--line);
  background: var(--ink-2);
  transition: border-color 0.2s var(--ease);
}

.page-about .a-shift[open] {
  border-left-color: var(--gold);
}

.page-about .a-shift summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 16px;
  padding: 15px 18px;
  cursor: pointer;
  list-style: none;
}

.page-about .a-shift summary::-webkit-details-marker {
  display: none;
}

.page-about .a-shift__slot {
  font-family: var(--mono);
  font-size: 0.9375rem;
  letter-spacing: 0.18em;
  color: var(--gold);
}

.page-about .a-shift__time {
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  color: var(--muted);
}

.page-about .a-shift__halls {
  margin-left: auto;
  font-size: 0.8125rem;
  letter-spacing: 0.06em;
  color: var(--paper);
}

.page-about .a-shift__body {
  padding: 2px 18px 20px;
  border-top: 1px solid var(--line);
  margin-top: 2px;
}

.page-about .a-shift__body p {
  margin: 14px 0 0;
  font-size: 0.9375rem;
  line-height: 1.85;
  color: var(--muted);
}

/* 版本沿革刻度 */
.page-about .a-timeline {
  list-style: none;
  margin: 34px 0 0;
  padding: 0;
  display: grid;
  gap: 26px;
}

@media (min-width: 880px) {
  .page-about .a-timeline {
    grid-template-columns: repeat(6, minmax(0, 1fr));
    gap: 0;
  }
}

.page-about .a-era {
  position: relative;
  display: grid;
  gap: 6px;
  align-content: start;
  border-top: 1px solid var(--line);
  padding-top: 18px;
}

@media (min-width: 880px) {
  .page-about .a-era {
    padding-right: 18px;
  }
}

.page-about .a-era::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: 9px;
  height: 9px;
  background: var(--gold);
  transform: translateY(-5px) rotate(45deg);
}

.page-about .a-era__ver {
  font-family: var(--mono);
  font-size: 0.6875rem;
  letter-spacing: 0.26em;
  color: var(--muted);
}

.page-about .a-era__year {
  font-family: var(--mono);
  font-size: 1.25rem;
  line-height: 1.1;
  letter-spacing: 0.04em;
  color: var(--paper);
}

.page-about .a-era__count {
  font-family: var(--mono);
  font-size: 0.8125rem;
  letter-spacing: 0.04em;
  color: var(--gold);
}

.page-about .a-era__note {
  font-size: 0.8125rem;
  line-height: 1.75;
  color: var(--muted);
  margin: 6px 0 0;
}

/* 术语表 */
.page-about .a-terms {
  display: grid;
  gap: 0;
  margin-top: 26px;
  border-top: 1px solid var(--line);
}

.page-about .a-term {
  border-bottom: 1px solid var(--line);
}

.page-about .a-term__word {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 15px 4px;
  cursor: pointer;
  list-style: none;
  font-family: var(--serif);
  font-weight: 900;
  font-size: 1rem;
  letter-spacing: 0.02em;
  color: var(--paper);
  transition: color 0.2s var(--ease);
}

.page-about .a-term__word::-webkit-details-marker {
  display: none;
}

.page-about .a-term__word::after {
  content: "＋";
  font-family: var(--mono);
  font-size: 0.875rem;
  color: var(--gold);
  flex: 0 0 auto;
}

.page-about .a-term[open] .a-term__word::after {
  content: "－";
}

.page-about .a-term__word:hover,
.page-about .a-term[open] .a-term__word {
  color: var(--gold-bright);
}

.page-about .a-term__body {
  padding: 0 4px 18px;
}

.page-about .a-term__body p {
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.85;
  color: var(--muted);
}

/* 延伸阅读 */
.page-about .a-reads ul {
  list-style: none;
  margin: 32px 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .a-reads a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 15px 4px;
  border-bottom: 1px solid var(--line);
  color: var(--paper);
  text-decoration: none;
  font-size: 0.9375rem;
  line-height: 1.6;
  transition: color 0.2s var(--ease), padding-left 0.2s var(--ease);
}

.page-about .a-reads a::after {
  content: "→";
  flex: 0 0 auto;
  font-family: var(--mono);
  color: var(--gold);
}

.page-about .a-reads a:hover {
  color: var(--gold-bright);
  padding-left: 12px;
}

@media (prefers-reduced-motion: reduce) {
  .page-about .a-toc .toc__link,
  .page-about .a-shift,
  .page-about .a-reads a,
  .page-about .a-term__word,
  .page-about .a-step summary {
    transition: none;
  }
}