.page-about .about-lede {
  position: relative;
  padding: 26px 0 26px;
  border-bottom: 1px solid var(--line);
}

.page-about .about-lede::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    114deg,
    rgba(232, 239, 230, 0.04) 0 1px,
    transparent 1px 10px
  );
  opacity: 0.7;
}

.page-about .about-lede__kicker {
  margin: 0 0 14px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--brass-lit);
}

.page-about .about-lede h1 {
  margin: 0 0 18px;
  max-width: 26ch;
  font-size: clamp(1.7rem, 6.2vw, 2.7rem);
  line-height: 1.16;
}

.page-about .about-lede__text {
  margin: 0 0 26px;
  max-width: 70ch;
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-facts > div {
  margin: 0;
  padding: 12px 14px;
  background: var(--panel);
}

.page-about .about-facts dt {
  margin: 0 0 6px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.page-about .about-facts dd {
  margin: 0;
  font-size: 15px;
  line-height: 1.5;
  color: var(--text);
}

.page-about .about-block {
  padding: 40px 0;
  border-bottom: 1px solid var(--line);
}

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

.page-about .about-block h2 {
  margin: 0 0 16px;
  font-size: clamp(1.32rem, 4.6vw, 1.9rem);
  line-height: 1.2;
}

.page-about .about-block p {
  max-width: 72ch;
  margin: 0 0 16px;
  line-height: 1.8;
  color: var(--text);
}

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

.page-about .about-block a {
  color: var(--neon);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

.page-about .about-block a:hover,
.page-about .about-block a:focus-visible {
  color: var(--brass-lit);
}

.page-about .about-figure {
  margin: 22px 0 26px;
  border: 1px solid var(--line);
}

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

.page-about .about-note {
  margin: 18px 0 0;
  padding-left: 14px;
  border-left: 2px solid var(--karst);
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
  max-width: 72ch;
}

/* 定位 / 边界 双栏 */
.page-about .scope-split {
  display: grid;
  gap: 1px;
  margin-top: 24px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .scope-col {
  padding: 18px 16px 20px;
  background: var(--panel);
}

.page-about .scope-col--off {
  background: var(--panel-2);
}

.page-about .scope-col__title {
  margin: 0 0 12px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--brass-lit);
}

.page-about .scope-col ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .scope-col li {
  position: relative;
  padding: 8px 0 8px 18px;
  font-size: 15px;
  line-height: 1.6;
  color: var(--text);
  border-top: 1px solid var(--line);
}

.page-about .scope-col li:first-child {
  border-top: 0;
  padding-top: 2px;
}

.page-about .scope-col li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 17px;
  width: 7px;
  height: 7px;
  background: var(--karst-lift);
}

.page-about .scope-col li:first-child::before {
  top: 11px;
}

.page-about .scope-col--off li::before {
  width: 8px;
  height: 1.5px;
  top: 19px;
  background: var(--muted);
}

.page-about .scope-col--off li:first-child::before {
  top: 13px;
}

/* 沿革阶段 */
.page-about .phase-list {
  margin-top: 4px;
  border-top: 1px solid var(--line);
}

.page-about .phase {
  position: relative;
  padding-left: 16px;
  border-bottom: 1px solid var(--line);
}

.page-about .phase::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, var(--brass), rgba(168, 127, 46, 0.12));
}

.page-about .phase > summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 14px;
  padding: 15px 0;
  cursor: pointer;
  list-style: none;
  transition: color 180ms var(--ease);
}

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

.page-about .phase > summary::after {
  content: "展开";
  margin-left: auto;
  padding: 2px 8px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--brass-lit);
  border: 1px solid var(--brass);
}

.page-about .phase[open] > summary::after {
  content: "收起";
  color: var(--neon);
  border-color: var(--karst-lift);
}

.page-about .phase > summary:hover,
.page-about .phase > summary:focus-visible {
  color: var(--brass-lit);
}

.page-about .phase > summary:focus-visible {
  outline: 2px solid var(--neon);
  outline-offset: 2px;
}

.page-about .phase__code {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--brass-lit);
}

.page-about .phase__title {
  font-size: 1.0625rem;
  font-weight: 700;
  color: var(--text);
}

.page-about .phase__body {
  padding: 0 0 18px;
  max-width: 70ch;
}

.page-about .phase__body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

/* 覆盖范围 */
.page-about .about-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 18px;
  margin: 18px 0 14px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.page-about .legend-chip {
  display: inline-block;
  width: 10px;
  height: 10px;
  margin-right: 6px;
  vertical-align: -1px;
}

.page-about .legend-chip--a {
  background: var(--karst);
  opacity: 0.85;
}

.page-about .legend-chip--b {
  background: var(--karst);
  opacity: 0.45;
}

.page-about .legend-chip--c {
  background: var(--karst);
  opacity: 0.18;
}

.page-about .zone-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  padding: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .zone {
  position: relative;
  padding: 11px 12px 13px;
  background: var(--panel);
  outline: 1px solid transparent;
  outline-offset: -2px;
  transition: outline-color 180ms var(--ease), background-color 180ms var(--ease);
}

.page-about .zone::before {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--karst);
  pointer-events: none;
}

.page-about .zone--a::before {
  opacity: 0.3;
}

.page-about .zone--b::before {
  opacity: 0.16;
}

.page-about .zone--c::before {
  opacity: 0.06;
}

.page-about .zone > * {
  position: relative;
  display: block;
}

.page-about .zone:hover,
.page-about .zone:focus-within {
  outline-color: var(--neon);
  background: var(--panel-2);
}

.page-about .zone__code {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--brass-lit);
}

.page-about .zone__name {
  margin: 5px 0 7px;
  font-size: 15px;
  font-weight: 700;
  line-height: 1.3;
  color: var(--text);
}

.page-about .zone__meta {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--muted);
}

/* 编辑编制 */
.page-about .roles {
  display: grid;
  gap: 1px;
  margin-top: 22px;
  padding: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .role {
  padding: 18px 16px 20px;
  background: var(--panel);
}

.page-about .role__name {
  margin: 0 0 6px;
  font-size: 1rem;
  font-weight: 700;
  color: var(--text);
}

.page-about .role__count {
  margin: 0 0 14px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--neon);
}

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

.page-about .role__list dt {
  margin: 12px 0 4px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.page-about .role__list dt:first-child {
  margin-top: 0;
}

.page-about .role__list dd {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--text);
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

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

/* 版本沿革 */
.page-about .filter-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 20px 0 14px;
}

.page-about .versions-layout {
  display: grid;
  gap: 24px;
}

.page-about .versions-table th[scope="row"] {
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--brass-lit);
  white-space: nowrap;
}

.page-about .versions-table tbody tr {
  transition: opacity 140ms var(--ease);
}

.page-about .versions-table tbody tr.is-filtered {
  display: none;
}

.page-about .versions-aside {
  display: grid;
  gap: 18px;
  align-content: start;
}

.page-about .versions-aside .media-frame {
  margin: 0;
  border: 1px solid var(--line);
}

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

.page-about .versions-aside .aside-note {
  margin: 0;
}

/* 备案与联络 */
.page-about .contact-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 22px 0 4px;
  padding: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .contact-cell {
  padding: 13px 14px;
  background: var(--panel);
}

.page-about .contact-cell__label {
  margin: 0 0 7px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.page-about .contact-cell__value {
  margin: 0;
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.6;
  color: var(--text);
  word-break: break-word;
}

/* 误解澄清 */
.page-about .myth-list {
  margin: 4px 0 0;
  border-top: 1px solid var(--line);
}

.page-about .myth {
  position: relative;
  padding: 16px 0 16px 16px;
  border-bottom: 1px solid var(--line);
}

.page-about .myth::before {
  content: "";
  position: absolute;
  left: 0;
  top: 22px;
  width: 2px;
  height: 14px;
  background: var(--brass);
}

.page-about .myth dt {
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.5;
  color: var(--text);
}

.page-about .myth dd {
  margin: 0;
  max-width: 72ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .myth dd a {
  color: var(--neon);
}

/* 收束 */
.page-about .about-outro {
  border-top: 1px solid var(--line);
  border-bottom: 0;
}

.page-about .about-links {
  margin: 6px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-links li {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 13px 14px;
  background: var(--panel);
  transition: background-color 180ms var(--ease);
}

.page-about .about-links li:hover {
  background: var(--panel-2);
}

.page-about .about-links a {
  font-size: 15px;
  font-weight: 700;
  color: var(--neon);
  text-decoration: none;
}

.page-about .about-links a:hover,
.page-about .about-links a:focus-visible {
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .about-links span {
  font-size: 13px;
  line-height: 1.65;
  color: var(--muted);
}

/* 窄屏到宽屏 */
@media (min-width: 640px) {
  .page-about .zone-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 880px) {
  .page-about .about-lede {
    padding: 40px 0 34px;
  }

  .page-about .about-lede__text {
    font-size: 1.0625rem;
  }

  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

  .page-about .zone-grid {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

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

  .page-about .versions-layout {
    grid-template-columns: minmax(0, 2fr) minmax(0, 1fr);
    gap: 32px;
    align-items: start;
  }

  .page-about .contact-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

  .page-about .about-links li:last-child {
    grid-column: 1 / -1;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .zone,
  .page-about .phase > summary,
  .page-about .about-links li,
  .page-about .versions-table tbody tr {
    transition: none;
  }
}