.page-about {
  --about-rule: var(--clay-line-soft);
  --about-shadow: 5px 7px 0 var(--clay-shadow);
  background: var(--paper);
  color: var(--ink);
}

.page-about img {
  max-width: 100%;
  height: auto;
}

.page-about [id] {
  scroll-margin-top: 96px;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb {
  padding-top: 20px;
  font-size: 13px;
}

.page-about .breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  color: var(--moss);
}

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

.page-about .breadcrumb a {
  color: var(--grass);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color .18s var(--ease);
}

.page-about .breadcrumb a:hover {
  border-bottom-color: var(--grass);
}

.page-about .about-label {
  color: var(--moss);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: 24px 0 42px;
}

.page-about .about-hero__grid {
  display: grid;
  gap: 30px;
}

.page-about .about-hero__title {
  font-family: var(--serif);
  font-weight: 800;
  font-size: 32px;
  line-height: 1.16;
  letter-spacing: -0.01em;
  margin: 12px 0 18px;
  max-width: 15em;
}

.page-about .about-hero__lede {
  font-size: 17px;
}

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

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

.page-about .about-axis {
  display: block;
  width: 100%;
  height: auto;
  background: var(--sand);
  border: 1px solid var(--clay-line);
  box-shadow: var(--about-shadow);
}

.page-about .about-axis__rings circle {
  fill: none;
  stroke: var(--clay-line-soft);
  stroke-dasharray: 4 6;
}

.page-about .about-axis__rings circle:first-child {
  stroke: var(--grass);
  stroke-opacity: .55;
  stroke-dasharray: none;
}

.page-about .about-axis__lines line {
  stroke: var(--grass);
  stroke-width: 1.4;
  transition: stroke .2s var(--ease), stroke-width .2s var(--ease);
}

.page-about .about-axis__lines line:hover {
  stroke: var(--cinnabar);
  stroke-width: 2.6;
}

.page-about .about-axis__pt {
  fill: var(--moss);
}

.page-about .about-axis__pt--on {
  fill: var(--grass);
}

.page-about .about-axis__pt--now {
  fill: var(--cinnabar);
}

.page-about .about-axis__labels text {
  font-family: var(--sans);
  font-size: 14px;
  letter-spacing: .08em;
  fill: var(--ink-deep);
}

.page-about .about-axis__caption {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-top: 14px;
}

.page-about .about-axis__note {
  color: var(--moss);
}

/* ---------- 章节通用 ---------- */
.page-about .about-section {
  padding: 44px 0;
}

.page-about .about-band {
  padding: 48px 0;
}

.page-about .about-head {
  max-width: 44em;
}

.page-about .about-h2 {
  margin: 12px 0 0;
  letter-spacing: -0.005em;
}

.page-about .about-head__lede {
  margin-top: 14px;
}

/* ---------- 01 三条线索 ---------- */
.page-about .scope-grid {
  display: grid;
  gap: 18px;
  margin-top: 26px;
}

.page-about .scope-card {
  padding: 22px 20px 24px;
  box-shadow: var(--about-shadow);
}

.page-about .scope-card__idx {
  display: block;
  color: var(--clay);
  margin-bottom: 10px;
}

.page-about .scope-card__title {
  font-family: var(--serif);
  font-size: 21px;
  font-weight: 700;
  margin: 0 0 10px;
}

.page-about .scope-card p {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.75;
}

.page-about .scope-boundary {
  margin: 24px 0 0;
  padding: 4px 0 4px 18px;
  border-left: 3px solid var(--cinnabar);
  font-size: 15px;
  line-height: 1.75;
  max-width: 52em;
}

.page-about .scope-boundary a,
.page-about .flow-note a {
  color: var(--grass);
  text-decoration: none;
  border-bottom: 1px solid var(--clay-line);
}

.page-about .scope-boundary a:hover,
.page-about .flow-note a:hover {
  border-bottom-color: var(--grass);
}

/* ---------- 02 归档方法 ---------- */
.page-about .archive-grid {
  display: grid;
  gap: 26px;
  margin-top: 26px;
}

.page-about .archive-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--clay-line);
}

.page-about .archive-steps li {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 12px;
  padding: 16px 0;
  border-bottom: 1px solid var(--about-rule);
}

.page-about .archive-steps__n {
  color: var(--grass);
}

.page-about .archive-steps strong {
  display: block;
  font-family: var(--serif);
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 5px;
}

.page-about .archive-steps p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--ink);
  opacity: .88;
}

/* ---------- 03 四步流程 ---------- */
.page-about .flow-grid {
  display: grid;
  gap: 26px;
  margin-top: 26px;
}

.page-about .flow-band {
  display: grid;
  gap: 12px;
}

.page-about .step {
  border: 1px solid var(--clay-line);
  box-shadow: 3px 4px 0 var(--clay-shadow);
  background: var(--paper);
}

.page-about .step--1 { background: rgba(47, 107, 94, .05); }
.page-about .step--2 { background: rgba(47, 107, 94, .09); }
.page-about .step--3 { background: rgba(47, 107, 94, .13); }
.page-about .step--4 {
  background: var(--mist);
  border-color: var(--grass);
}

.page-about .step summary {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 14px 16px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .step summary::after {
  content: "＋";
  margin-left: auto;
  font-family: var(--mono);
  font-size: 14px;
  color: var(--moss);
}

.page-about .step[open] summary::after {
  content: "－";
  color: var(--cinnabar);
}

.page-about .step__idx {
  color: var(--clay);
}

.page-about .step__name {
  font-family: var(--serif);
  font-size: 19px;
  font-weight: 700;
}

.page-about .step__body {
  padding: 12px 16px 16px;
  border-top: 1px dashed var(--about-rule);
  font-size: 15px;
  line-height: 1.75;
}

.page-about .step__body p {
  margin: 0;
}

.page-about .flow-figure {
  margin: 0;
  align-self: start;
}

.page-about .flow-figure .media-frame__img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.page-about .flow-note {
  margin: 26px 0 0;
  padding-top: 16px;
  border-top: 1px solid var(--clay-line);
  font-size: 15px;
  line-height: 1.75;
  max-width: 54em;
}

/* ---------- 04 团队分工 ---------- */
.page-about .team-grid {
  display: grid;
  gap: 20px;
  margin-top: 26px;
}

.page-about .team-count {
  padding: 26px 24px 28px;
  box-shadow: var(--about-shadow);
}

.page-about .team-count__n {
  display: block;
  font-family: var(--mono);
  font-size: 56px;
  line-height: 1;
  letter-spacing: .02em;
  color: var(--amber);
}

.page-about .team-count p {
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--paper-on-dark);
}

.page-about .team-roster {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .team-roster li {
  padding: 18px 0;
  border-bottom: 1px solid var(--about-rule);
}

.page-about .team-roster li:first-child {
  border-top: 1px solid var(--clay-line);
}

.page-about .team-roster h3 {
  font-family: var(--serif);
  font-size: 18px;
  font-weight: 700;
  margin: 0 0 6px;
}

.page-about .team-roster p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  max-width: 40em;
}

/* ---------- 05 资料互通 ---------- */
.page-about .network-grid {
  display: grid;
  gap: 26px;
  margin-top: 26px;
}

.page-about .network-list {
  list-style: none;
  margin: 20px 0 0;
  padding: 0;
  border-top: 1px solid var(--clay-line);
}

.page-about .network-list li {
  padding: 12px 0;
  border-bottom: 1px solid var(--about-rule);
  font-size: 15px;
  line-height: 1.72;
}

.page-about .network-list strong {
  display: inline-block;
  min-width: 5em;
  font-family: var(--serif);
  font-weight: 700;
  color: var(--grass);
}

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

.page-about .network-figure .media-frame__img {
  width: 100%;
  aspect-ratio: 14 / 9;
  object-fit: cover;
}

/* ---------- 06 更正路径 ---------- */
.page-about .correct-grid {
  display: grid;
  gap: 28px;
  margin-top: 26px;
}

.page-about .correct-main .prose {
  margin-top: 0;
}

.page-about .qa {
  border-top: 1px solid var(--clay-line);
}

.page-about .qa:last-of-type {
  border-bottom: 1px solid var(--clay-line);
}

.page-about .qa summary {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 15px 0;
  cursor: pointer;
  list-style: none;
  font-family: var(--serif);
  font-size: 17px;
  font-weight: 700;
}

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

.page-about .qa summary::after {
  content: "＋";
  margin-left: auto;
  font-family: var(--mono);
  font-weight: 400;
  font-size: 14px;
  color: var(--moss);
}

.page-about .qa[open] summary::after {
  content: "－";
  color: var(--cinnabar);
}

.page-about .qa__body {
  padding: 0 0 16px;
  font-size: 15px;
  line-height: 1.75;
}

.page-about .qa__body p {
  margin: 0;
}

.page-about .qa__body ul {
  margin: 0;
  padding-left: 18px;
}

.page-about .qa__body li {
  margin-bottom: 6px;
}

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

.page-about .correct-figure {
  margin: 0;
  align-self: start;
}

.page-about .correct-figure .media-frame__img {
  width: 100%;
  aspect-ratio: 7 / 4;
  object-fit: cover;
}

/* ---------- 媒体框统一 ---------- */
.page-about .media-frame {
  max-width: 100%;
}

.page-about .media-frame__caption {
  font-size: 13px;
  line-height: 1.65;
  color: var(--moss);
}

/* ---------- 响应式 ---------- */
@media (min-width: 700px) {
  .page-about .about-hero__title {
    font-size: 42px;
  }

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

  .page-about .scope-card--wide {
    grid-column: span 2;
  }

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

@media (min-width: 1000px) {
  .page-about .about-hero {
    padding: 40px 0 58px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: 46px;
    align-items: center;
  }

  .page-about .about-hero__title {
    font-size: 48px;
  }

  .page-about .about-section {
    padding: 62px 0;
  }

  .page-about .about-band {
    padding: 66px 0;
  }

  .page-about .scope-grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 4fr) minmax(0, 3fr);
    gap: 20px;
  }

  .page-about .scope-card--wide {
    grid-column: auto;
  }

  .page-about .about-h2 {
    max-width: 20em;
  }

  .page-about .archive-grid {
    grid-template-columns: minmax(0, 6fr) minmax(0, 6fr);
    gap: 38px;
    align-items: start;
  }

  .page-about .flow-grid {
    grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
    gap: 34px;
    align-items: start;
  }

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

  .page-about .team-grid {
    grid-template-columns: minmax(0, 4fr) minmax(0, 8fr);
    gap: 34px;
    align-items: start;
  }

  .page-about .network-grid {
    grid-template-columns: minmax(0, 6fr) minmax(0, 6fr);
    gap: 38px;
    align-items: center;
  }

  .page-about .correct-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 38px;
    align-items: start;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-axis__lines line,
  .page-about .breadcrumb a {
    transition: none;
  }
}