.page-about {
  --rail-w: 220px;
  background: var(--c-paper);
  color: var(--c-ink-deep);
  font-family: var(--font-body);
  font-size: var(--fs-16);
  line-height: 1.78;
}

/* ---------- 刊头 ---------- */
.page-about .about-masthead {
  position: relative;
  background: var(--c-ink);
  color: var(--c-white);
  border-bottom: 3px solid var(--c-ink-deep);
  padding: 36px 0 52px;
}

.page-about .about-masthead::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: linear-gradient(to right, var(--c-silver-22) 1px, transparent 1px);
  background-size: var(--grid-step) 100%;
  pointer-events: none;
}

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

.page-about .crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .08em;
}

.page-about .crumb {
  color: var(--c-silver);
  text-decoration: none;
}

.page-about .crumb:hover,
.page-about .crumb:focus-visible {
  color: var(--c-gold);
}

.page-about .crumb-sep {
  color: var(--c-silver-40);
}

.page-about .crumb-current {
  color: var(--c-white);
}

.page-about .eyebrow {
  margin: 28px 0 0;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .16em;
  color: var(--c-gold);
}

.page-about .masthead-title {
  margin: 14px 0 0;
  font-family: var(--font-title);
  font-weight: 900;
  font-size: clamp(30px, 4.6vw, 54px);
  line-height: 1.1;
  letter-spacing: -.02em;
  max-width: 22ch;
  color: var(--c-white);
}

.page-about .masthead-lede {
  margin: 22px 0 0;
  max-width: 62ch;
  font-size: var(--fs-16);
  line-height: 1.8;
  color: var(--c-white-88);
}

.page-about .masthead-facts {
  list-style: none;
  margin: 34px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  border-top: 1px solid var(--c-silver-40);
}

.page-about .masthead-facts li {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 16px;
  padding: 12px 0;
  border-bottom: 1px solid var(--c-silver-40);
  font-size: var(--fs-14);
  min-width: 0;
}

.page-about .fa-k {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .1em;
  color: var(--c-silver);
  flex: none;
}

.page-about .fa-v {
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--c-white);
  text-align: right;
  min-width: 0;
  overflow-wrap: anywhere;
}

@media (min-width: 720px) {
  .page-about .masthead-facts {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: 40px;
  }
}

@media (min-width: 1080px) {
  .page-about .masthead-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 主体两栏 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
}

@media (min-width: 1080px) {
  .page-about .about-body {
    grid-template-columns: var(--rail-w) minmax(0, 1fr);
    column-gap: 56px;
  }
}

/* ---------- 侧栏 ---------- */
.page-about .about-rail {
  padding: 36px 0 0;
  min-width: 0;
}

@media (min-width: 1080px) {
  .page-about .about-rail {
    position: sticky;
    top: 96px;
    align-self: start;
    padding: 56px 24px 48px 0;
    border-right: 1px solid var(--c-line);
  }
}

.page-about .rail-block {
  margin: 0 0 30px;
}

.page-about .rail-heading {
  margin: 0 0 12px;
  padding-bottom: 6px;
  border-bottom: 2px solid var(--c-orange);
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 700;
  letter-spacing: .14em;
  color: var(--c-ink-deep);
}

.page-about .rail-years {
  list-style: none;
  margin: 0;
  padding: 0 0 4px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .rail-years > li {
  flex: 0 0 auto;
}

.page-about .rail-year {
  display: block;
  padding: 8px 12px;
  border: 1px solid var(--c-ink-deep);
  background: var(--c-white);
  color: var(--c-ink-deep);
  text-decoration: none;
  white-space: nowrap;
  font-size: var(--fs-14);
  line-height: 1.4;
  transition: background-color .16s ease, color .16s ease, box-shadow .16s ease;
}

.page-about .rail-year:hover,
.page-about .rail-year:focus-visible {
  background: var(--c-gold);
  box-shadow: var(--shadow-chip);
}

.page-about .rail-year-num {
  font-family: var(--font-mono);
  font-weight: 700;
  margin-right: 8px;
}

.page-about .rail-year-txt {
  color: inherit;
  opacity: .78;
  font-size: var(--fs-12);
}

@media (min-width: 1080px) {
  .page-about .rail-years {
    display: block;
    overflow: visible;
    padding: 0;
  }
  .page-about .rail-years > li {
    display: block;
  }
  .page-about .rail-year {
    border: 0;
    border-left: 3px solid var(--c-line);
    background: transparent;
    padding: 7px 0 7px 14px;
    white-space: normal;
    font-size: var(--fs-14);
  }
  .page-about .rail-year:hover,
  .page-about .rail-year:focus-visible {
    border-left-color: var(--c-gold);
    background: transparent;
    box-shadow: none;
    color: var(--c-orange);
  }
  .page-about .rail-year-num {
    display: block;
    margin: 0 0 2px;
  }
  .page-about .rail-year-txt {
    display: block;
  }
}

.page-about .rail-code {
  margin: 0 0 12px;
  padding: 10px 12px;
  background: var(--c-ink);
  border: 2px solid var(--c-ink-deep);
  font-family: var(--font-mono);
  font-size: var(--fs-20);
  font-weight: 700;
  letter-spacing: .02em;
  text-align: center;
  color: var(--c-gold);
  overflow-wrap: anywhere;
}

.page-about .rail-note {
  margin: 20px 0 0;
  padding-top: 12px;
  border-top: 1px solid var(--c-line);
  font-size: var(--fs-12);
  line-height: 1.72;
  color: var(--c-inktext-72);
}

/* ---------- 内容列 ---------- */
.page-about .about-flow {
  min-width: 0;
  padding: 44px 0 64px;
}

@media (min-width: 1080px) {
  .page-about .about-flow {
    padding: 56px 0 88px;
  }
}

.page-about .flow-section {
  margin: 0 0 52px;
  min-width: 0;
}

.page-about .flow-section:last-child {
  margin-bottom: 0;
}

.page-about .flow-head {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 16px;
}

.page-about .flow-index {
  flex: none;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 700;
  letter-spacing: .1em;
  padding: 3px 8px;
  background: var(--c-orange);
  color: var(--c-white);
}

.page-about .flow-title {
  margin: 0;
  min-width: 0;
  font-family: var(--font-title);
  font-weight: 900;
  font-size: clamp(22px, 2.6vw, 32px);
  line-height: 1.2;
  letter-spacing: -.02em;
  color: var(--c-ink-deep);
}

.page-about .flow-lede {
  margin: 0 0 28px;
  max-width: 64ch;
  font-size: var(--fs-16);
  line-height: 1.8;
  color: var(--c-inktext-72);
}

/* 深色面板 */
.page-about .flow-section--mid {
  background: var(--c-ink-mid);
}

.page-about .flow-section--dark {
  position: relative;
  background: var(--c-ink);
  color: var(--c-white);
  border: 3px solid var(--c-ink-deep);
  box-shadow: var(--shadow-hard);
  padding: clamp(24px, 3.4vw, 44px);
}

.page-about .flow-section--dark .flow-title {
  color: var(--c-white);
}

.page-about .flow-section--dark .flow-lede {
  color: var(--c-white-88);
}

.page-about .flow-section--dark .flow-index {
  background: var(--c-gold);
  color: var(--c-ink-deep);
}

/* ---------- 01 立场与边界 ---------- */
.page-about .scope-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 20px;
}

@media (min-width: 780px) {
  .page-about .scope-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 28px;
  }
}

.page-about .scope-col {
  border: 2px solid var(--c-ink-deep);
  background: var(--c-white);
  padding: 20px 22px 22px;
  min-width: 0;
}

.page-about .scope-col--limit {
  background: transparent;
  border-style: dashed;
}

.page-about .scope-title {
  margin: 0 0 14px;
  font-family: var(--font-title);
  font-weight: 900;
  font-size: var(--fs-16);
  letter-spacing: -.01em;
  color: var(--c-ink-deep);
}

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

.page-about .scope-list li {
  display: flex;
  gap: 12px;
  padding: 10px 0;
  border-top: 1px solid var(--c-line);
  font-size: var(--fs-14);
  line-height: 1.72;
  color: var(--c-inktext-72);
}

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

.page-about .scope-code {
  flex: none;
  padding-top: 2px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .06em;
  color: var(--c-orange);
}

/* ---------- 02 整理四步 ---------- */
.page-about .method-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
}

@media (min-width: 860px) {
  .page-about .method-layout {
    grid-template-columns: minmax(0, .78fr) minmax(0, 1.22fr);
    gap: 36px;
    align-items: start;
  }
}

.page-about .method-figure {
  margin: 0;
  min-width: 0;
}

.page-about .method-figure .figure-frame {
  aspect-ratio: 7 / 9;
  overflow: hidden;
  border: 2px solid var(--c-silver-40);
  background: var(--c-ink-mid);
}

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

.page-about .method-main {
  min-width: 0;
}

.page-about .method-svg {
  display: block;
  width: 100%;
  height: auto;
  margin: 0 0 6px;
}

@media (max-width: 719px) {
  .page-about .method-svg {
    display: none;
  }
}

.page-about .method-steps {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .method-step {
  border-top: 1px solid var(--c-silver-40);
}

.page-about .method-step:last-child {
  border-bottom: 1px solid var(--c-silver-40);
}

.page-about .step-summary {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 16px 0;
  cursor: pointer;
  list-style: none;
  transition: color .16s ease;
}

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

.page-about .step-summary:hover,
.page-about .step-summary:focus-visible {
  color: var(--c-gold);
}

.page-about .step-num {
  flex: none;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 700;
  letter-spacing: .06em;
  padding: 2px 7px;
  background: var(--c-gold);
  color: var(--c-ink-deep);
}

.page-about .step-name {
  flex: 1 1 auto;
  min-width: 0;
  font-family: var(--font-title);
  font-weight: 900;
  font-size: var(--fs-20);
  letter-spacing: -.01em;
}

.page-about .step-hint {
  flex: none;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .08em;
  color: var(--c-silver);
}

@media (max-width: 560px) {
  .page-about .step-hint {
    display: none;
  }
}

.page-about .step-grid {
  margin: 0 0 20px;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

@media (min-width: 720px) {
  .page-about .step-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
  }
}

.page-about .step-grid dt {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .1em;
  color: var(--c-gold);
}

.page-about .step-grid dd {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.72;
  color: var(--c-white-88);
}

/* ---------- 03 批次对照 ---------- */
.page-about .batch-figure {
  margin: 0 0 28px;
}

.page-about .batch-figure .figure-frame {
  aspect-ratio: 21 / 9;
  overflow: hidden;
  border: 1px solid var(--c-silver-40);
}

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

.page-about .batch-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
}

@media (min-width: 760px) {
  .page-about .batch-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px;
  }
}

.page-about .batch-card {
  display: flex;
  flex-direction: column;
  padding: 20px 22px 22px;
  border: 1px solid var(--c-silver-40);
  background: rgba(251, 251, 247, .04);
  min-width: 0;
}

.page-about .batch-card--current {
  border-color: var(--c-gold);
  background: rgba(224, 163, 60, .09);
}

.page-about .batch-tag {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .12em;
  color: var(--c-silver);
}

.page-about .batch-tag--current {
  color: var(--c-gold);
}

.page-about .batch-code {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: var(--fs-20);
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--c-white);
  overflow-wrap: anywhere;
}

.page-about .batch-card--current .batch-code {
  color: var(--c-gold);
}

.page-about .batch-list {
  list-style: none;
  margin: 0 0 14px;
  padding: 0;
}

.page-about .batch-list li {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 14px;
  padding: 10px 0;
  border-top: 1px solid var(--c-silver-40);
  font-size: var(--fs-14);
  color: var(--c-white-70);
}

.page-about .batch-val {
  font-family: var(--font-mono);
  font-size: var(--fs-20);
  font-weight: 700;
  line-height: 1;
  color: var(--c-white);
}

.page-about .batch-card--current .batch-val {
  color: var(--c-teal);
}

.page-about .batch-note {
  flex: 1 1 auto;
  margin: 0 0 16px;
  font-size: var(--fs-14);
  line-height: 1.72;
  color: var(--c-white-70);
}

.page-about .batch-foot {
  margin: 26px 0 0;
  padding-left: 14px;
  border-left: 3px solid var(--c-orange);
  font-size: var(--fs-14);
  line-height: 1.76;
  color: var(--c-white-70);
}

/* ---------- 04 发展节点 ---------- */
.page-about .timeline {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .timeline-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 8px;
  padding: 22px 0;
  border-top: 1px solid var(--c-line);
  scroll-margin-top: 112px;
}

.page-about .timeline-item:last-child {
  border-bottom: 1px solid var(--c-line);
}

@media (min-width: 640px) {
  .page-about .timeline-item {
    grid-template-columns: 108px minmax(0, 1fr);
    gap: 28px;
    align-items: start;
  }
}

.page-about .timeline-year {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--fs-28);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.01em;
  color: var(--c-ink);
}

.page-about .timeline-year::after {
  content: "";
  display: block;
  width: 32px;
  height: 3px;
  margin-top: 10px;
  background: var(--c-gold);
}

.page-about .timeline-body {
  min-width: 0;
}

.page-about .timeline-title {
  margin: 0 0 8px;
  font-family: var(--font-title);
  font-weight: 900;
  font-size: var(--fs-20);
  letter-spacing: -.01em;
  color: var(--c-ink-deep);
}

.page-about .timeline-body p {
  margin: 0;
  max-width: 58ch;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--c-inktext-72);
}

.page-about .nodes-figure {
  margin: 36px 0 0;
}

.page-about .nodes-figure .figure-frame {
  aspect-ratio: 7 / 2;
  overflow: hidden;
  border: 2px solid var(--c-line);
}

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

/* ---------- 05 研究组分工 ---------- */
.page-about .team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
}

@media (min-width: 700px) {
  .page-about .team-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
  }
}

.page-about .team-card {
  padding: 18px 20px 20px;
  border: 2px solid var(--c-ink-deep);
  background: var(--c-white);
  box-shadow: var(--shadow-chip);
  min-width: 0;
}

.page-about .team-index {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .12em;
  color: var(--c-orange);
}

.page-about .team-name {
  margin: 0 0 12px;
  font-family: var(--font-title);
  font-weight: 900;
  font-size: var(--fs-20);
  letter-spacing: -.01em;
  color: var(--c-ink-deep);
}

.page-about .team-count {
  margin: 0 0 12px;
  padding-top: 10px;
  border-top: 1px solid var(--c-line);
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .06em;
  color: var(--c-inktext-72);
}

.page-about .team-num {
  margin-right: 4px;
  font-size: var(--fs-28);
  font-weight: 700;
  color: var(--c-ink);
}

.page-about .team-desc {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.74;
  color: var(--c-inktext-72);
}

.page-about .team-cross {
  margin-top: 28px;
  padding: 18px 20px;
  background: var(--c-white);
  border: 1px solid var(--c-line);
  border-left: 4px solid var(--c-teal);
}

.page-about .team-cross-title {
  margin: 0 0 8px;
  font-family: var(--font-title);
  font-weight: 900;
  font-size: var(--fs-16);
  color: var(--c-ink-deep);
}

.page-about .team-cross p {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.76;
  color: var(--c-inktext-72);
}

/* ---------- 06 复核与纠错 ---------- */
.page-about .verify-flow {
  list-style: none;
  margin: 0 0 28px;
  padding: 0;
}

.page-about .verify-flow li {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 14px;
  padding: 14px 0;
  border-top: 1px solid var(--c-silver-40);
}

.page-about .verify-flow li:last-child {
  border-bottom: 1px solid var(--c-silver-40);
}

.page-about .vf-num {
  padding-top: 4px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .08em;
  color: var(--c-gold);
}

.page-about .verify-flow p {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.76;
  color: var(--c-white-88);
}

.page-about .verify-ask {
  border: 2px solid var(--c-gold);
  padding: 20px 22px 22px;
}

.page-about .verify-ask-title {
  margin: 0 0 12px;
  font-family: var(--font-title);
  font-weight: 900;
  font-size: var(--fs-16);
  letter-spacing: -.01em;
  color: var(--c-gold);
}

.page-about .verify-ask ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .verify-ask li {
  position: relative;
  padding-left: 20px;
  margin-bottom: 8px;
  font-size: var(--fs-14);
  line-height: 1.72;
  color: var(--c-white-88);
}

.page-about .verify-ask li:last-child {
  margin-bottom: 0;
}

.page-about .verify-ask li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--c-gold);
}

.page-about .verify-contact {
  margin: 22px 0 0;
  font-size: var(--fs-14);
  line-height: 1.82;
  color: var(--c-white-70);
}

.page-about .verify-contact strong {
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--c-white);
  overflow-wrap: anywhere;
}

/* ---------- 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .rail-year,
  .page-about .step-summary {
    transition: none;
  }
}