.page-about .breadcrumb {
  padding-block: clamp(14px, 2vw, 22px);
}

.page-about .breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 12px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: var(--fs-2);
  color: var(--muted);
}

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

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

.page-about .breadcrumb li + li::before {
  content: "/";
  margin-right: 12px;
  color: var(--line);
}

/* ---------- 开篇：杂志式左右跨页 ---------- */
.page-about .opening {
  display: grid;
  gap: clamp(28px, 4vw, 56px);
  padding-block: clamp(24px, 5vw, 64px) clamp(40px, 6vw, 80px);
}

.page-about .opening__lead {
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-width: 0;
}

.page-about .opening h1 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--fs-8);
  line-height: 1.16;
  letter-spacing: -0.01em;
  color: var(--paper);
  text-wrap: balance;
}

.page-about .opening__dek {
  margin: 22px 0 0;
  max-width: 46ch;
  font-size: var(--fs-4);
  line-height: 1.8;
  color: var(--muted);
}

.page-about .seal-rule {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: clamp(24px, 3vw, 34px) 0;
}

.page-about .seal-rule span {
  flex: 1 1 40px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--line), transparent);
}

.page-about .seal-rule i {
  flex: 0 0 auto;
  width: 10px;
  height: 10px;
  background: var(--gold);
  transform: rotate(45deg);
}

.page-about .opening__facts {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 24px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .opening__facts li {
  font-size: var(--fs-2);
  letter-spacing: 0.04em;
  color: var(--muted);
}

.page-about .opening__facts li::before {
  content: "";
  display: inline-block;
  width: 6px;
  height: 6px;
  margin-right: 9px;
  background: var(--jade);
  transform: rotate(45deg);
  vertical-align: middle;
}

.page-about .opening__figure {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--ink-mid);
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.45);
}

.page-about .opening__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

/* ---------- 章节条 ---------- */
.page-about .chapters {
  padding-block: 12px;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .chapters ol {
  display: flex;
  gap: clamp(18px, 4vw, 44px);
  list-style: none;
  margin: 0;
  padding: 0 0 2px;
  overflow-x: auto;
}

.page-about .chapters a {
  display: inline-flex;
  align-items: baseline;
  gap: 9px;
  padding: 10px 2px;
  white-space: nowrap;
  font-size: var(--fs-2);
  letter-spacing: 0.06em;
  color: var(--paper);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .chapters a:hover,
.page-about .chapters a:focus-visible {
  color: var(--gold-soft);
  border-bottom-color: var(--gold);
}

.page-about .chapters .num {
  font-family: var(--font-num);
  font-size: var(--fs-1);
  color: var(--gold);
  letter-spacing: 0.08em;
}

/* ---------- 四类档案 ---------- */
.page-about .archives {
  display: grid;
  gap: clamp(28px, 4vw, 52px);
  padding-block: clamp(44px, 7vw, 92px);
  border-top: 1px solid var(--line);
}

.page-about .archives h2,
.page-about .coverage h2,
.page-about .why h2,
.page-about .versions h2 {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: var(--fs-6);
  line-height: 1.3;
  color: var(--paper);
  text-wrap: balance;
}

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

.page-about .archives__note {
  margin: 18px 0 0;
  font-size: var(--fs-3);
  line-height: 1.8;
  color: var(--muted);
}

.page-about .archives__figure {
  margin: clamp(22px, 3vw, 32px) 0 0;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--ink-mid);
}

.page-about .archives__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 1 / 1;
  object-fit: cover;
}

.page-about .archive-list {
  display: grid;
  gap: clamp(14px, 2vw, 20px);
  list-style: none;
  margin: 0;
  padding: 0;
  min-width: 0;
}

.page-about .archive {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: 26px 22px 20px;
  background: var(--ink-mid);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .archive:hover {
  transform: translateY(-2px);
  border-color: var(--gold-soft);
  box-shadow: 0 16px 36px rgba(0, 0, 0, 0.42);
}

.page-about .archive__num {
  position: absolute;
  top: 18px;
  right: 20px;
  font-family: var(--font-num);
  font-size: var(--fs-2);
  letter-spacing: 0.1em;
  color: var(--line);
}

.page-about .archive svg {
  width: 34px;
  height: 34px;
  fill: none;
  stroke: var(--gold);
  stroke-width: 1.4;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.page-about .archive--rules svg {
  stroke: var(--jade);
}

.page-about .archive h3 {
  margin: 16px 0 8px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: var(--fs-5);
  color: var(--paper);
}

.page-about .archive p {
  margin: 0;
  font-size: var(--fs-3);
  line-height: 1.75;
  color: var(--muted);
}

.page-about .archive__link {
  margin-top: 16px;
  align-self: flex-start;
  font-size: var(--fs-2);
  letter-spacing: 0.06em;
  color: var(--gold-soft);
  text-decoration: none;
  border-bottom: 1px solid var(--line);
  padding-bottom: 2px;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .archive__link::after {
  content: " →";
}

.page-about .archive__link:hover,
.page-about .archive__link:focus-visible {
  color: var(--paper);
  border-bottom-color: var(--gold);
}

/* ---------- 版本演进带 ---------- */
.page-about .versions {
  position: relative;
  margin-block: clamp(20px, 4vw, 48px);
  padding-block: clamp(52px, 8vw, 104px);
  overflow: hidden;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--ink-deep);
}

.page-about .versions__bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.26;
}

.page-about .versions::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, var(--ink-deep) 0%, rgba(8, 21, 36, 0.7) 42%, var(--ink-deep) 100%);
}

.page-about .versions__inner {
  position: relative;
  z-index: 1;
}

.page-about .versions__note {
  margin: 18px 0 0;
  max-width: 62ch;
  font-size: var(--fs-3);
  line-height: 1.8;
  color: var(--muted);
}

.page-about .plates {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  list-style: none;
  margin: clamp(28px, 4vw, 46px) 0 0;
  padding: 0 0 10px;
  overflow-x: auto;
  scroll-snap-type: x proximity;
}

.page-about .plates > li {
  flex: 0 0 auto;
  width: min(232px, 74vw);
  scroll-snap-align: start;
}

.page-about .plate {
  background: rgba(18, 41, 63, 0.9);
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .plate:hover {
  border-color: var(--gold-soft);
}

.page-about .plate[open] {
  border-color: var(--gold);
  background: var(--ink-mid);
}

.page-about .plate summary {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: start;
  gap: 12px;
  padding: 22px 18px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .plate__body {
  display: block;
}

.page-about .plate__num {
  display: block;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 48px;
  line-height: 1;
  color: var(--gold);
  font-variant-numeric: tabular-nums;
}

.page-about .plate__label {
  display: block;
  margin-top: 10px;
  font-size: var(--fs-2);
  letter-spacing: 0.08em;
  color: var(--paper);
}

.page-about .plate__mark::before {
  content: "+";
  font-family: var(--font-num);
  font-size: var(--fs-4);
  line-height: 1;
  color: var(--gold-soft);
}

.page-about .plate[open] .plate__mark::before {
  content: "−";
}

.page-about .plate p {
  margin: 0;
  padding: 0 18px 22px;
  font-size: var(--fs-2);
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 覆盖与规模 ---------- */
.page-about .coverage {
  display: grid;
  gap: clamp(26px, 4vw, 48px);
  padding-block: clamp(44px, 7vw, 92px);
}

.page-about .coverage__note {
  margin: 18px 0 0;
  font-size: var(--fs-3);
  line-height: 1.8;
  color: var(--muted);
}

.page-about .stats {
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  overflow: hidden;
  min-width: 0;
}

.page-about .stat {
  background: var(--ink-mid);
  padding: 24px 22px;
}

.page-about .stat__num {
  display: block;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: var(--fs-7);
  line-height: 1;
  color: var(--paper);
  font-variant-numeric: tabular-nums;
}

.page-about .stat__label {
  display: block;
  margin-top: 10px;
  font-size: var(--fs-2);
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-about .stat p {
  margin: 12px 0 0;
  font-size: var(--fs-2);
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 长期使用 ---------- */
.page-about .why {
  padding-block: clamp(44px, 7vw, 88px) clamp(56px, 8vw, 104px);
  border-top: 1px solid var(--line);
}

.page-about .why__lead {
  max-width: var(--read);
  margin: 22px 0 0;
  font-size: var(--fs-4);
  line-height: 1.85;
  color: var(--muted);
}

.page-about .why-list {
  max-width: var(--read);
  list-style: none;
  margin: clamp(28px, 4vw, 42px) 0 0;
  padding: 0;
}

.page-about .why-list li {
  padding: 26px 0;
  border-top: 1px solid var(--line);
}

.page-about .why-list li:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .why-list h3 {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: var(--fs-5);
  color: var(--paper);
}

.page-about .why-list .num {
  font-family: var(--font-num);
  font-size: var(--fs-2);
  color: var(--gold);
  letter-spacing: 0.08em;
}

.page-about .why-list p {
  margin: 0;
  font-size: var(--fs-3);
  line-height: 1.8;
  color: var(--muted);
}

.page-about .why__closing {
  max-width: var(--read);
  margin-top: clamp(30px, 4vw, 46px);
}

.page-about .why__closing p {
  margin: 0;
  font-size: var(--fs-3);
  line-height: 1.85;
  color: var(--paper);
}

.page-about .why__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 26px;
  margin-top: 24px;
}

.page-about .why__links a {
  font-size: var(--fs-2);
  letter-spacing: 0.06em;
  color: var(--gold-soft);
  text-decoration: none;
  padding: 6px 0;
  border-bottom: 1px solid var(--line);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .why__links a:hover,
.page-about .why__links a:focus-visible {
  color: var(--paper);
  border-bottom-color: var(--gold);
}

/* ---------- 桌面端栅格 ---------- */
@media (min-width: 960px) {
  .page-about .opening {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    align-items: center;
  }

  .page-about .archives {
    grid-template-columns: minmax(0, 4fr) minmax(0, 8fr);
    align-items: start;
  }

  .page-about .coverage {
    grid-template-columns: minmax(0, 4fr) minmax(0, 8fr);
    align-items: start;
  }
}

@media (min-width: 640px) {
  .page-about .archive-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about .archive:hover {
    transform: none;
  }
}