.page-about {
  --about-aside: 236px;
  --about-gap: clamp(18px, 3vw, 30px);
  background-color: var(--ink-900);
  color: var(--paper);
  padding-bottom: clamp(40px, 6vw, 96px);
  overflow-x: clip;
}

.page-about .breadcrumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  padding-top: 22px;
  font-size: 13px;
  color: var(--muted);
}

.page-about .breadcrumbs a {
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid var(--line);
  padding-bottom: 1px;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.page-about .breadcrumbs a:hover,
.page-about .breadcrumbs a:focus-visible {
  color: var(--signal);
  border-color: var(--signal-deep);
}

.page-about .breadcrumbs__sep {
  color: var(--line);
}

/* 封面章节 */
.page-about .about-cover {
  position: relative;
  padding: clamp(26px, 5vw, 58px) 0 clamp(28px, 4.6vw, 52px);
  border-bottom: 1px solid var(--line);
  background-image:
    repeating-linear-gradient(90deg, rgba(31, 74, 63, 0.28) 0 1px, transparent 1px 76px),
    repeating-linear-gradient(0deg, rgba(31, 74, 63, 0.16) 0 1px, transparent 1px 76px);
  background-position: left top;
}

.page-about .about-cover .eyebrow {
  color: var(--sand);
  letter-spacing: 0.14em;
}

.page-about .about-cover h1 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-size: clamp(34px, 6.2vw, 82px);
  line-height: 1.03;
  letter-spacing: -0.02em;
  font-weight: 700;
  color: var(--paper);
  max-width: 17ch;
}

.page-about .about-cover__lede {
  margin: clamp(18px, 2.6vw, 26px) 0 0;
  max-width: 62ch;
  font-size: clamp(15px, 1.5vw, 18px);
  line-height: 1.78;
  color: var(--paper);
}

.page-about .about-cover__figures {
  display: flex;
  flex-wrap: wrap;
  gap: clamp(20px, 3.4vw, 52px);
  margin-top: clamp(24px, 3.4vw, 36px);
  padding-top: clamp(16px, 2.4vw, 24px);
  border-top: 1px solid var(--line);
}

.page-about .cover-figure {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .cover-figure__num {
  font-family: var(--font-mono);
  font-size: clamp(26px, 3.4vw, 42px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--sand);
  font-variant-numeric: tabular-nums;
}

.page-about .cover-figure__cap {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.page-about .about-index {
  list-style: none;
  margin: clamp(24px, 4vw, 40px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-index li {
  background: var(--ink-800);
}

.page-about .about-index a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 12px 14px;
  font-size: 14px;
  color: var(--paper);
  text-decoration: none;
  transition: background 0.22s ease, color 0.22s ease;
}

.page-about .about-index a:hover,
.page-about .about-index a:focus-visible {
  background: var(--ink-700);
  color: var(--signal);
}

.page-about .about-index__no {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--sand);
}

@media (min-width: 640px) {
  .page-about .about-index {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* 章节骨架 */
.page-about .chapter {
  padding: clamp(36px, 5.6vw, 82px) 0;
  border-bottom: 1px solid var(--line);
}

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

.page-about .chapter__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: center;
  column-gap: 16px;
  row-gap: 10px;
  padding-top: 14px;
  margin-bottom: clamp(20px, 3vw, 34px);
  border-top: 1px solid var(--line);
}

.page-about .chapter__head .chapter-no {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.14em;
  color: var(--sand);
  font-variant-numeric: tabular-nums;
}

.page-about .chapter__title {
  grid-column: 1 / -1;
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(23px, 3.5vw, 42px);
  line-height: 1.14;
  letter-spacing: -0.01em;
  font-weight: 700;
  color: var(--paper);
  max-width: 22ch;
}

.page-about .chapter__lede {
  margin: 0 0 clamp(18px, 2.8vw, 28px);
  max-width: 66ch;
  font-size: 15px;
  line-height: 1.78;
  color: var(--muted);
}

.page-about .sub-title {
  margin: clamp(26px, 4vw, 40px) 0 0;
  font-family: var(--font-display);
  font-size: clamp(16px, 2vw, 20px);
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--paper);
  padding-left: 12px;
  border-left: 3px solid var(--sand);
}

/* 两栏错落 */
.page-about .about-split {
  display: grid;
  gap: var(--about-gap);
}

@media (min-width: 900px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 1fr) var(--about-aside);
    align-items: start;
  }
}

.page-about .prose p {
  margin: 0 0 1em;
  font-size: 15px;
  line-height: 1.8;
  color: var(--paper);
  max-width: 66ch;
}

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

/* 侧栏纸张叠层卡 */
.page-about .aside-card {
  position: relative;
  padding: 18px;
  background: var(--ink-800);
  border: 1px solid var(--line);
  border-top: 3px solid var(--sand);
  box-shadow: 6px 6px 0 -1px var(--ink-900), 6px 6px 0 0 var(--line);
}

.page-about .aside-card__label {
  display: block;
  margin-bottom: 14px;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--sand);
}

.page-about .figure-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .figure-list li {
  display: grid;
  gap: 3px;
  padding-bottom: 12px;
  border-bottom: 1px dashed var(--line);
}

.page-about .figure-list li:last-child {
  padding-bottom: 0;
  border-bottom: 0;
}

.page-about .figure-list__num {
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 700;
  line-height: 1.1;
  color: var(--signal);
  font-variant-numeric: tabular-nums;
}

.page-about .figure-list__cap {
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .about-aside-visual {
  display: grid;
  gap: 16px;
}

.page-about .figure-list--tight {
  padding: 14px 16px;
  background: var(--ink-800);
  border: 1px solid var(--line);
}

/* 图像 */
.page-about img {
  max-width: 100%;
}

.page-about .media-frame {
  margin: 0 0 clamp(20px, 3vw, 32px);
}

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

/* 时间线 */
.page-about .timeline {
  list-style: none;
  margin: clamp(22px, 3.4vw, 36px) 0 0;
  padding: 0 0 0 30px;
  position: relative;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  background: linear-gradient(180deg, var(--sand), var(--line) 72%, transparent);
}

.page-about .timeline > li {
  position: relative;
  margin-bottom: 10px;
}

.page-about .timeline > li::before {
  content: "";
  position: absolute;
  left: -30px;
  top: 18px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--sand);
  box-shadow: 0 0 0 4px rgba(232, 197, 122, 0.14);
}

.page-about .tl {
  border: 1px solid var(--line);
  background: var(--ink-800);
  transition: background 0.22s ease, border-color 0.22s ease;
}

.page-about .tl[open] {
  background: var(--ink-700);
  border-color: var(--signal-deep);
}

.page-about .tl summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 14px;
  padding: 12px 14px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .tl summary:hover {
  background: var(--ink-700);
}

.page-about .tl summary:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: -2px;
}

.page-about .tl__year {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  color: var(--sand);
  font-variant-numeric: tabular-nums;
}

.page-about .tl__label {
  font-size: 14.5px;
  color: var(--paper);
}

.page-about .tl__hint {
  margin-left: auto;
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--muted);
}

.page-about .tl[open] .tl__hint {
  color: var(--signal);
}

.page-about .tl__body {
  margin: 0;
  padding: 12px 14px 14px;
  border-top: 1px solid var(--line);
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--muted);
}

/* 数字带 */
.page-about .stat-band {
  display: grid;
  gap: 1px;
  margin: clamp(20px, 3vw, 32px) 0 clamp(20px, 3vw, 30px);
  background: var(--line);
  border: 1px solid var(--line);
}

@media (min-width: 700px) {
  .page-about .stat-band {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .stat-band__cell {
  background: var(--ink-900);
  padding: clamp(16px, 2.4vw, 26px);
}

.page-about .stat-band__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(34px, 5.4vw, 60px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--signal);
  font-variant-numeric: tabular-nums;
}

.page-about .stat-band__cap {
  display: block;
  margin-top: 10px;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--muted);
}

/* 七栏分类 */
.page-about .cat-grid {
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .cat-cell {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-height: 138px;
  padding: 16px;
  background: var(--ink-800);
  transition: background 0.24s ease;
}

.page-about .cat-cell:hover,
.page-about .cat-cell:focus-within {
  background: var(--ink-700);
}

.page-about .cat-cell__no {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.12em;
  color: var(--sand);
}

.page-about .cat-cell__name {
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .cat-cell__desc {
  font-size: 13px;
  line-height: 1.66;
  color: var(--muted);
}

.page-about .cat-cell__hint {
  margin-top: auto;
  font-size: 12px;
  color: var(--signal);
  opacity: 0;
  transform: translateY(4px);
  transition: opacity 0.24s ease, transform 0.24s ease;
}

.page-about .cat-cell:hover .cat-cell__hint,
.page-about .cat-cell:focus-within .cat-cell__hint {
  opacity: 1;
  transform: none;
}

@media (hover: none) {
  .page-about .cat-cell__hint {
    opacity: 1;
    transform: none;
  }
}

@media (min-width: 820px) {
  .page-about .cat-grid {
    grid-template-columns: repeat(7, minmax(0, 1fr));
  }
  .page-about .cat-cell--lg {
    grid-column: span 3;
  }
  .page-about .cat-cell--md {
    grid-column: span 2;
  }
}

/* 七栏字段 */
.page-about .field-grid {
  display: grid;
  gap: 1px;
  margin-top: clamp(14px, 2.4vw, 22px);
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .field-cell {
  background: var(--ink-800);
  padding: 14px;
}

.page-about .field-cell__name {
  display: block;
  margin-bottom: 6px;
  font-size: 13px;
  font-weight: 600;
  color: var(--sand);
}

.page-about .field-cell__desc {
  font-size: 12.5px;
  line-height: 1.62;
  color: var(--muted);
}

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

@media (min-width: 980px) {
  .page-about .field-grid {
    grid-template-columns: repeat(7, minmax(0, 1fr));
  }
}

/* 团队 */
.page-about .team-grid {
  display: grid;
  gap: clamp(14px, 2vw, 22px);
}

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

.page-about .team-card {
  padding: 20px;
  background: var(--ink-800);
  border: 1px solid var(--line);
  border-top: 3px solid var(--sand);
}

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

.page-about .team-card__num {
  font-family: var(--font-mono);
  font-size: 32px;
  font-weight: 700;
  line-height: 1;
  color: var(--signal);
  font-variant-numeric: tabular-nums;
}

.page-about .team-card__name {
  font-size: 16px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .team-card p {
  margin: 12px 0 0;
  font-size: 14px;
  line-height: 1.74;
  color: var(--muted);
}

/* 服务准则 */
.page-about .principle-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .principle-list li {
  display: grid;
  gap: 8px;
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
}

@media (min-width: 760px) {
  .page-about .principle-list li {
    grid-template-columns: 108px minmax(0, 1fr);
    gap: 26px;
    align-items: baseline;
  }
}

.page-about .principle-list__tag {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--sand);
}

.page-about .principle-list p {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--paper);
  max-width: 64ch;
}

.page-about .principle-list a {
  color: var(--signal);
  text-decoration: none;
  border-bottom: 1px solid var(--signal-deep);
  padding-bottom: 1px;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.page-about .principle-list a:hover,
.page-about .principle-list a:focus-visible {
  color: var(--paper);
  border-color: var(--paper);
}

/* CTA 信号块 */
.page-about .about-cta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-top: clamp(22px, 3.6vw, 34px);
  padding: 18px 20px;
  text-decoration: none;
}

/* 联系信息 */
.page-about .about-contact {
  display: grid;
  gap: 0 clamp(18px, 3vw, 34px);
  margin-top: clamp(8px, 1.6vw, 14px);
  border-top: 1px solid var(--line);
}

@media (min-width: 820px) {
  .page-about .about-contact {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .about-contact__row {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 12px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-contact__label {
  flex: 0 0 auto;
  min-width: 76px;
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: var(--muted);
}

.page-about .about-contact__value {
  flex: 1 1 200px;
  min-width: 0;
  font-size: 14.5px;
  line-height: 1.68;
  color: var(--paper);
  overflow-wrap: anywhere;
}

.page-about a.about-contact__value {
  color: var(--signal);
  text-decoration: none;
  border-bottom: 1px solid var(--signal-deep);
  padding-bottom: 1px;
}

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

.page-about .copy-note {
  flex: 1 1 100%;
  min-height: 0;
  font-size: 12px;
  color: var(--signal);
}

.page-about .copy-btn {
  flex: 0 0 auto;
}

/* 显现 */
.page-about [data-reveal] {
  opacity: 1;
}

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}