.page-about {
  --ab-muted: #a9b8cc;
  --ab-num: clamp(40px, 7vw, 64px);
  --ab-rule: 1px solid var(--line);
  background: var(--ink);
  color: var(--paper);
  padding-bottom: clamp(40px, 6vw, 72px);
  overflow-x: hidden;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  border-bottom: var(--ab-rule);
  background:
    linear-gradient(118deg, rgba(20, 42, 76, 0) 0 54%, rgba(20, 42, 76, 0.9) 54% 100%),
    linear-gradient(180deg, #071223 0%, var(--ink) 100%);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -10%;
  right: 18%;
  width: 1px;
  height: 130%;
  background: linear-gradient(180deg, transparent, rgba(0, 230, 210, 0.45), transparent);
  transform: rotate(18deg);
  pointer-events: none;
}

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

.page-about .breadcrumb {
  padding-top: clamp(16px, 2.6vw, 26px);
  margin-bottom: clamp(10px, 2vw, 18px);
}

.page-about .hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 44px);
  padding: clamp(4px, 1vw, 10px) 0 clamp(32px, 5vw, 60px);
}

@media (min-width: 960px) {
  .page-about .hero-inner {
    grid-template-columns: minmax(0, 1fr);
    align-items: end;
  }
}

.page-about .hero-title {
  margin: 12px 0 18px;
  font-size: clamp(28px, 5vw, 44px);
  font-weight: 800;
  line-height: 1.16;
  letter-spacing: -0.01em;
  color: var(--paper);
  max-width: 20em;
}

.page-about .hero-lead {
  margin: 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ab-muted);
}

.page-about .hero-stats {
  list-style: none;
  margin: clamp(6px, 2vw, 18px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

@media (min-width: 760px) {
  .page-about .hero-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .hero-stats li {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px 18px;
  background: var(--ink);
}

.page-about .stat-num {
  font-family: var(--font-mono);
  font-size: clamp(22px, 3vw, 30px);
  font-weight: 600;
  line-height: 1;
  color: var(--cyan);
}

.page-about .stat-unit {
  margin-left: 2px;
  font-size: 0.58em;
  color: var(--cyan-soft);
}

.page-about .stat-label {
  font-size: 12px;
  line-height: 1.4;
  letter-spacing: 0.04em;
  color: var(--rock);
}

/* ---------- 章节骨架 ---------- */
.page-about .chapter {
  padding: clamp(36px, 6vw, 84px) 0;
  border-bottom: var(--ab-rule);
}

.page-about .chapter-head {
  display: flex;
  align-items: flex-start;
  gap: clamp(12px, 2vw, 22px);
  margin-bottom: clamp(20px, 3vw, 36px);
}

.page-about .chapter-num {
  flex: none;
  font-family: var(--font-mono);
  font-size: var(--ab-num);
  font-weight: 700;
  line-height: 0.78;
  letter-spacing: -0.03em;
  color: rgba(0, 230, 210, 0.24);
  position: relative;
  padding-top: 4px;
}

.page-about .chapter-num::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -8px;
  width: 26px;
  height: 2px;
  background: var(--cyan);
}

.page-about .chapter-heading {
  min-width: 0;
}

.page-about .chapter-title {
  margin: 0 0 8px;
  font-size: clamp(21px, 3vw, 32px);
  font-weight: 800;
  line-height: 1.28;
  color: var(--paper);
}

.page-about .chapter-kicker {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--cyan);
}

.page-about .chapter-intro {
  max-width: 62ch;
  margin: 0 0 clamp(20px, 3vw, 32px);
  font-size: 15px;
  line-height: 1.8;
  color: var(--ab-muted);
}

.page-about .chapter-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3.2vw, 44px);
}

@media (min-width: 900px) {
  .page-about .chapter-grid {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
    align-items: start;
  }
  .page-about .chapter-grid--flip {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr);
    align-items: center;
  }
}

.page-about .chapter-body p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ab-muted);
}

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

/* ---------- 图片 ---------- */
.page-about .about-figure {
  position: relative;
  margin: 0;
  border: 1px solid var(--line);
  background: var(--panel);
  overflow: hidden;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  aspect-ratio: 5 / 7;
  object-fit: cover;
}

.page-about .about-figure--wide img {
  aspect-ratio: 14 / 9;
}

.page-about .about-figure::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(165deg, rgba(0, 230, 210, 0.1) 0%, rgba(5, 10, 22, 0) 48%, rgba(5, 10, 22, 0.72) 100%);
  pointer-events: none;
}

.page-about .about-figure figcaption {
  position: relative;
  z-index: 1;
  padding: 12px 14px;
  font-size: 12px;
  line-height: 1.65;
  letter-spacing: 0.02em;
  color: var(--rock);
  border-top: 1px solid var(--line);
  background: var(--panel);
}

/* ---------- 时间线 ---------- */
.page-about .timeline {
  list-style: none;
  margin: 0;
  padding: 12px 0 0 32px;
  position: relative;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 20px;
  bottom: 24px;
  width: 2px;
  background: linear-gradient(180deg, var(--cyan) 0%, var(--line) 55%, rgba(36, 64, 110, 0.15) 100%);
}

.page-about .tl-node {
  position: relative;
  list-style: none;
}

.page-about .tl-item {
  position: relative;
  border-bottom: 1px dashed rgba(36, 64, 110, 0.7);
}

.page-about .tl-node:last-child .tl-item {
  border-bottom: 0;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -28px;
  top: 20px;
  width: 8px;
  height: 8px;
  background: var(--cyan);
  box-shadow: 0 0 0 3px rgba(0, 230, 210, 0.14);
  transition: box-shadow 0.2s var(--ease);
}

.page-about .tl-item[open]::before {
  box-shadow: 0 0 0 5px rgba(0, 230, 210, 0.18);
}

.page-about .tl-item > summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 12px;
  padding: 14px 0;
  cursor: pointer;
  list-style: none;
  transition: color 0.2s var(--ease);
}

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

.page-about .tl-item > summary:hover .tl-name {
  color: var(--cyan-soft);
}

.page-about .tl-ver {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--ink);
  background: var(--cyan);
  padding: 2px 8px;
}

.page-about .tl-name {
  font-size: clamp(16px, 2vw, 19px);
  font-weight: 700;
  color: var(--paper);
  transition: color 0.2s var(--ease);
}

.page-about .tl-plus {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--cyan);
  transition: transform 0.2s var(--ease);
}

.page-about .tl-item[open] .tl-plus {
  transform: rotate(45deg);
}

.page-about .tl-body {
  padding: 0 0 18px 0;
  border-left: 2px solid rgba(0, 230, 210, 0.35);
  padding-left: 14px;
  margin-bottom: 4px;
}

.page-about .tl-body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ab-muted);
  max-width: 62ch;
}

/* ---------- 团队分工 ---------- */
.page-about .roles {
  list-style: none;
  margin: 22px 0;
  padding: 0;
  border-top: var(--ab-rule);
}

.page-about .roles li {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  gap: 2px 14px;
  padding: 16px 0;
  border-bottom: var(--ab-rule);
}

@media (min-width: 620px) {
  .page-about .roles li {
    grid-template-columns: 52px 156px minmax(0, 1fr);
    align-items: baseline;
    gap: 0 16px;
  }
}

.page-about .role-n {
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 600;
  line-height: 1;
  color: var(--orange);
}

.page-about .role-t {
  font-size: 15px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .role-d {
  grid-column: 1 / -1;
  margin-top: 6px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--ab-muted);
}

@media (min-width: 620px) {
  .page-about .role-d {
    grid-column: 3;
    margin-top: 0;
  }
}

.page-about .flow-note {
  margin: 0;
  padding: 16px 18px;
  font-size: 14px;
  line-height: 1.85;
  color: var(--ab-muted);
  background: var(--tactic);
  border-left: 2px solid var(--cyan);
}

/* ---------- 协作网络 ---------- */
.page-about .chapter-network {
  position: relative;
  overflow: hidden;
}

.page-about .network-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.page-about .network-bg img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.38;
}

.page-about .network-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(5, 10, 22, 0.94) 0%, rgba(5, 10, 22, 0.8) 56%, rgba(5, 10, 22, 0.97) 100%);
}

.page-about .chapter-network .container {
  position: relative;
  z-index: 1;
}

.page-about .network-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 52px);
}

@media (min-width: 900px) {
  .page-about .network-grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    align-items: center;
  }
}

.page-about .network-copy > p {
  margin: 0 0 20px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ab-muted);
  max-width: 60ch;
}

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

.page-about .partner-list li {
  padding: 14px 0;
  border-top: 1px solid rgba(36, 64, 110, 0.9);
}

.page-about .partner-list li:last-child {
  border-bottom: 1px solid rgba(36, 64, 110, 0.9);
}

.page-about .p-name {
  display: block;
  margin-bottom: 4px;
  font-size: 15px;
  font-weight: 700;
  color: var(--cyan);
}

.page-about .p-desc {
  display: block;
  font-size: 14px;
  line-height: 1.75;
  color: var(--ab-muted);
}

.page-about .network-map {
  padding: clamp(14px, 2.4vw, 24px);
  border: var(--ab-rule);
  background: rgba(11, 21, 38, 0.78);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 22px), calc(100% - 22px) 100%, 0 100%);
}

.page-about .dot-matrix {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  color: var(--cyan);
}

.page-about .map-note {
  margin: 10px 0 0;
  font-size: 12px;
  line-height: 1.7;
  letter-spacing: 0.02em;
  color: var(--rock);
}

/* ---------- 数据质量 ---------- */
.page-about .qa-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .qa-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 6px;
  padding: 18px 0;
  border-top: var(--ab-rule);
}

.page-about .qa-row:last-child {
  border-bottom: var(--ab-rule);
}

@media (min-width: 820px) {
  .page-about .qa-row {
    grid-template-columns: 34px minmax(0, 0.75fr) minmax(0, 1.75fr);
    align-items: baseline;
    gap: 0 24px;
    padding: 22px 0;
  }
}

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

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

.page-about .qa-desc {
  display: block;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ab-muted);
}

/* ---------- 资质 ---------- */
.page-about .cred-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

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

.page-about .cred {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: 18px 20px;
  background: linear-gradient(100deg, rgba(20, 42, 76, 0.92) 0%, rgba(11, 21, 38, 0.94) 100%);
  border-left: 2px solid var(--cyan);
  clip-path: polygon(0 0, calc(100% - 18px) 0, 100% 18px, 100% 100%, 0 100%);
}

.page-about .cred-badge {
  flex: none;
  padding: 3px 7px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  white-space: nowrap;
  color: var(--cyan);
  border: 1px solid rgba(0, 230, 210, 0.5);
}

.page-about .cred-text {
  font-size: 14px;
  line-height: 1.75;
  color: var(--ab-muted);
}

/* ---------- 后续入口 ---------- */
.page-about .about-next {
  padding-top: clamp(36px, 5.5vw, 72px);
}

.page-about .next-title {
  margin: 0 0 clamp(16px, 2.6vw, 26px);
  font-size: clamp(18px, 2.4vw, 24px);
  font-weight: 800;
  color: var(--paper);
}

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

@media (min-width: 680px) {
  .page-about .next-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

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

.page-about .next-card {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 20px 18px;
  background: var(--panel);
  text-decoration: none;
  color: inherit;
  transition: background 0.2s var(--ease);
}

.page-about .next-card:hover {
  background: var(--tactic);
}

.page-about .next-card:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

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

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

.page-about .next-d {
  font-size: 13px;
  line-height: 1.7;
  color: var(--rock);
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tl-item > summary,
  .page-about .tl-name,
  .page-about .tl-plus,
  .page-about .next-card {
    transition: none;
  }
  .page-about .tl-plus {
    transform: none;
  }
  .page-about .tl-item[open] .tl-plus {
    transform: rotate(45deg);
  }
}