.page-about {
  --rail-col: clamp(52px, 7vw, 104px);
  --node-size: 9px;
}

.page-about .crumbs {
  padding-top: 10px;
  padding-bottom: 4px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(26px, 5vw, 60px) 0 clamp(34px, 6vw, 84px);
  border-bottom: 1px solid var(--hair);
  background:
    radial-gradient(115% 88% at 84% 4%, rgba(122, 92, 240, .20), transparent 62%),
    radial-gradient(88% 70% at 6% 96%, rgba(228, 169, 60, .13), transparent 64%),
    var(--space);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: .5;
  background-image:
    linear-gradient(to right, rgba(44, 74, 143, .3) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(44, 74, 143, .3) 1px, transparent 1px);
  background-size: 76px 76px;
  -webkit-mask-image: radial-gradient(78% 68% at 46% 42%, #000 18%, transparent 78%);
  mask-image: radial-gradient(78% 68% at 46% 42%, #000 18%, transparent 78%);
}

.page-about .hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: clamp(26px, 4vw, 52px);
}

.page-about .hero-main h1 {
  margin: 14px 0 18px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(34px, 6.2vw, 72px);
  line-height: 1.05;
  letter-spacing: -.02em;
  color: var(--chalk);
  max-width: 16ch;
}

.page-about .lede {
  margin: 0;
  max-width: 60ch;
  font-size: clamp(16px, 1.5vw, 18px);
  line-height: 1.8;
  color: var(--mist);
}

.page-about .hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .hero-aside {
  padding: 20px 18px 22px;
  border: 1px solid var(--hair);
  border-radius: 3px;
  background: linear-gradient(165deg, rgba(22, 41, 92, .78), rgba(7, 17, 39, .9));
}

.page-about .aside-kicker {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .24em;
  text-transform: uppercase;
  color: var(--dim);
}

.page-about .hero-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px 12px;
}

.page-about .stat {
  display: flex;
  flex-direction: column;
  gap: 3px;
  min-width: 0;
}

.page-about .stat-num {
  font-family: var(--font-mono);
  font-size: clamp(24px, 3.4vw, 32px);
  font-weight: 600;
  line-height: 1;
  color: var(--gold);
}

.page-about .stat-unit {
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--gold-soft);
  margin-left: 2px;
}

.page-about .stat-label {
  font-size: 13px;
  line-height: 1.5;
  color: var(--dim);
}

.page-about .stat .stat-num + .stat-unit + .stat-label,
.page-about .stat .stat-num + .stat-label {
  margin-top: 2px;
}

/* ---------- 章节骨架 ---------- */
.page-about .chapter {
  border-bottom: 1px solid var(--hair);
}

.page-about .chapter-grid {
  display: grid;
  gap: clamp(14px, 3vw, 30px);
}

.page-about .chapter-rail {
  display: flex;
  align-items: center;
  gap: 12px;
}

.page-about .chapter-no {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--gold);
}

.page-about .chapter-rail-label {
  font-size: 13px;
  letter-spacing: .26em;
  color: var(--dim);
}

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

.page-about .section-title {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(26px, 3.6vw, 44px);
  line-height: 1.16;
  letter-spacing: -.015em;
  color: var(--chalk);
  max-width: 22ch;
}

.page-about .section-lede {
  margin: 0 0 clamp(22px, 3.4vw, 34px);
  max-width: 66ch;
  font-size: 17px;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .inline-link {
  color: var(--gold);
  text-decoration: none;
  border-bottom: 1px solid rgba(228, 169, 60, .45);
  transition: border-color var(--t) var(--ease), color var(--t) var(--ease);
}

.page-about .inline-link:hover,
.page-about .inline-link:focus-visible {
  color: var(--gold-soft);
  border-bottom-color: var(--gold-soft);
}

.page-about .media-frame {
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--hair);
  border-radius: 3px;
  background: var(--slate);
}

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

.page-about .media-caption {
  display: block;
  padding: 10px 14px 12px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--dim);
  border-top: 1px solid rgba(44, 74, 143, .55);
}

/* ---------- 时间轴 ---------- */
.page-about .timeline {
  list-style: none;
  margin: 0 0 clamp(26px, 4vw, 40px);
  padding: 0 0 0 26px;
  position: relative;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 10px;
  bottom: 12px;
  width: 1px;
  background: linear-gradient(to bottom, var(--gold), var(--hair) 22%, var(--hair));
}

.page-about .tl-item {
  position: relative;
  padding-bottom: clamp(20px, 3vw, 32px);
}

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

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 7px;
  width: var(--node-size);
  height: var(--node-size);
  border-radius: 50%;
  background: var(--space);
  border: 1px solid var(--gold);
  transition: background var(--t) var(--ease), box-shadow var(--t) var(--ease);
}

.page-about .tl-item:hover::before,
.page-about .tl-item:focus-within::before {
  background: var(--gold);
  box-shadow: 0 0 0 4px rgba(228, 169, 60, .16);
}

.page-about .tl-year {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--gold);
  margin-bottom: 6px;
}

.page-about .tl-title {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(18px, 2vw, 22px);
  line-height: 1.35;
  color: var(--chalk);
}

.page-about .tl-text {
  margin: 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .tl-note {
  margin: 0;
  max-width: 58ch;
  font-size: 14px;
  line-height: 1.7;
  color: var(--dim);
}

@media (hover: hover) and (pointer: fine) {
  .page-about .tl-note {
    max-height: 0;
    margin-top: 0;
    opacity: 0;
    overflow: hidden;
    transition: max-height 240ms var(--ease), opacity 200ms var(--ease), margin-top 200ms var(--ease);
  }

  .page-about .tl-item:hover .tl-note,
  .page-about .tl-item:focus-within .tl-note {
    max-height: 8em;
    margin-top: 8px;
    opacity: 1;
  }
}

@media (hover: none), (pointer: coarse) {
  .page-about .tl-note {
    margin-top: 8px;
  }
}

.page-about .timeline-figure {
  margin-top: clamp(8px, 2vw, 14px);
}

/* ---------- 服务网络 ---------- */
.page-about .chapter--network {
  background: linear-gradient(180deg, rgba(14, 31, 69, .55), rgba(7, 17, 39, 0) 78%);
}

.page-about .network-figure {
  margin-bottom: clamp(24px, 4vw, 38px);
}

.page-about .net-points {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .net-point {
  padding: 20px 18px 22px;
  border: 1px solid var(--hair);
  border-left: 2px solid rgba(44, 74, 143, .9);
  border-radius: 3px;
  background: rgba(14, 31, 69, .78);
  transition: border-color var(--t) var(--ease), background var(--t) var(--ease);
}

.page-about .net-point:hover {
  border-left-color: var(--gold);
  background: rgba(22, 41, 92, .86);
}

.page-about .net-point h3 {
  margin: 12px 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 19px;
  color: var(--chalk);
}

.page-about .net-point p {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--mist);
}

/* ---------- 会员分层 ---------- */
.page-about .tiers {
  display: grid;
  gap: 16px;
}

.page-about .tier {
  padding: 22px 18px 24px;
  border: 1px solid var(--hair);
  border-radius: 3px;
  background: linear-gradient(178deg, rgba(22, 41, 92, .74), rgba(10, 22, 52, .94));
  transition: border-color var(--t) var(--ease), transform var(--t) var(--ease);
}

.page-about .tier:hover,
.page-about .tier:focus-within {
  border-color: var(--gold);
  transform: translateY(-3px);
}

.page-about .tier-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
}

.page-about .tier-code {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--dim);
}

.page-about .tier-scale {
  margin: 18px 0 0;
  display: flex;
  align-items: baseline;
  gap: 6px;
  flex-wrap: wrap;
}

.page-about .tier-num {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: clamp(34px, 5vw, 46px);
  line-height: 1;
  color: var(--chalk);
}

.page-about .tier-unit {
  font-size: 14px;
  letter-spacing: .06em;
  color: var(--dim);
}

.page-about .tier-bar {
  position: relative;
  height: 4px;
  margin: 16px 0 14px;
  background: rgba(44, 74, 143, .6);
  overflow: hidden;
}

.page-about .tier-bar span {
  display: block;
  height: 100%;
  background: linear-gradient(90deg, var(--gold), var(--gold-soft));
  transition: width var(--t) var(--ease);
}

.page-about .tier--base .tier-bar span { width: 34%; }
.page-about .tier--pro .tier-bar span { width: 66%; }
.page-about .tier--elite .tier-bar span { width: 100%; }

.page-about .tier-deliver {
  margin: 0 0 12px;
  font-size: 15px;
  color: var(--mist);
}

.page-about .tier-deliver b {
  font-family: var(--font-mono);
  font-size: 17px;
  color: var(--gold);
  margin: 0 2px;
}

.page-about .tier-desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--mist);
}

.page-about .tier-footnote {
  margin: clamp(20px, 3vw, 30px) 0 0;
  padding-top: 18px;
  border-top: 1px solid var(--hair);
  max-width: 68ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--dim);
}

/* ---------- 团队岗位 ---------- */
.page-about .seq-grid {
  display: grid;
  gap: clamp(24px, 4vw, 40px);
}

.page-about .seq-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .seq-item {
  position: relative;
  padding: 16px 14px 16px 16px;
  border-left: 2px solid rgba(44, 74, 143, .85);
  background: rgba(14, 31, 69, .6);
  transition: border-color var(--t) var(--ease), background var(--t) var(--ease);
}

.page-about .seq-item:hover,
.page-about .seq-item:focus-within {
  border-left-color: var(--gold);
  background: rgba(22, 41, 92, .9);
}

.page-about .seq-code {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--dim);
  margin-bottom: 6px;
}

.page-about .seq-role {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 18px;
  color: var(--chalk);
}

.page-about .seq-duty {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--mist);
}

.page-about .seq-figure {
  align-self: start;
}

.page-about .seq-figure.media-frame {
  background: linear-gradient(150deg, var(--slate), var(--space));
  transition: border-color var(--t) var(--ease);
}

.page-about .seq-figure.media-frame:hover {
  border-color: var(--gold);
}

/* ---------- 专利 ---------- */
.page-about .patent-grid {
  display: grid;
  gap: 14px;
}

.page-about .patent-card {
  padding: 20px 18px 22px;
  border: 1px solid var(--hair);
  border-radius: 3px;
  background: rgba(7, 17, 39, .72);
  transition: border-color var(--t) var(--ease), background var(--t) var(--ease);
}

.page-about .patent-card:hover {
  border-color: rgba(228, 169, 60, .8);
  background: rgba(22, 41, 92, .7);
}

.page-about .patent-card p {
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .patent-note {
  margin: clamp(20px, 3vw, 30px) 0 0;
  padding: 16px 18px;
  border: 1px dashed rgba(44, 74, 143, .9);
  border-radius: 3px;
  max-width: 68ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist);
}

/* ---------- 合作生态 ---------- */
.page-about .partner-grid {
  display: grid;
  gap: 14px;
}

.page-about .partner-card {
  position: relative;
  padding: 22px 18px 24px;
  border: 1px solid var(--hair);
  border-radius: 3px;
  background: linear-gradient(200deg, rgba(22, 41, 92, .8), rgba(7, 17, 39, .92));
  overflow: hidden;
  transition: border-color var(--t) var(--ease);
}

.page-about .partner-card::after {
  content: "";
  position: absolute;
  right: -30px;
  top: -30px;
  width: 96px;
  height: 96px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(122, 92, 240, .3), transparent 68%);
  transition: opacity var(--t) var(--ease);
  opacity: .7;
}

.page-about .partner-card:hover {
  border-color: var(--violet);
}

.page-about .partner-card:hover::after {
  opacity: 1;
}

.page-about .partner-index {
  position: relative;
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--violet);
  margin-bottom: 14px;
}

.page-about .partner-card h3 {
  position: relative;
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 19px;
  color: var(--chalk);
}

.page-about .partner-card p {
  position: relative;
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--mist);
}

/* ---------- 服务衡量 ---------- */
.page-about .measure-grid {
  display: grid;
  gap: 14px;
  margin-bottom: clamp(24px, 3.6vw, 36px);
}

.page-about .measure-item {
  padding: 20px 16px 22px;
  border: 1px solid var(--hair);
  border-top: 2px solid var(--gold);
  border-radius: 3px;
  background: rgba(14, 31, 69, .74);
}

.page-about .measure-num {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: clamp(30px, 4.4vw, 42px);
  line-height: 1;
  color: var(--chalk);
}

.page-about .measure-unit {
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--gold);
  margin-left: 4px;
}

.page-about .measure-label {
  margin: 12px 0 6px;
  font-size: 15px;
  font-weight: 600;
  color: var(--mist);
}

.page-about .measure-desc {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: var(--dim);
}

.page-about .fold {
  border: 1px solid var(--hair);
  border-radius: 3px;
  background: rgba(7, 17, 39, .66);
  overflow: hidden;
}

.page-about .fold-summary {
  cursor: pointer;
  padding: 16px 18px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.5;
  color: var(--chalk);
  list-style: none;
  transition: color var(--t) var(--ease), background var(--t) var(--ease);
}

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

.page-about .fold-summary::before {
  content: "+";
  display: inline-block;
  width: 1.2em;
  font-family: var(--font-mono);
  color: var(--gold);
}

.page-about .fold[open] .fold-summary::before {
  content: "−";
}

.page-about .fold-summary:hover,
.page-about .fold-summary:focus-visible {
  background: rgba(22, 41, 92, .8);
  color: var(--gold-soft);
}

.page-about .fold-body {
  padding: 4px 18px 20px;
  border-top: 1px solid rgba(44, 74, 143, .6);
}

.page-about .fold-list {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .fold-list li {
  position: relative;
  padding-left: 18px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .fold-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .72em;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  border: 1px solid var(--jade);
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  padding: clamp(34px, 6vw, 76px) 0 clamp(40px, 6vw, 84px);
  background:
    radial-gradient(90% 78% at 22% 0%, rgba(122, 92, 240, .2), transparent 66%),
    var(--void);
}

.page-about .cta-panel {
  padding: clamp(26px, 4.4vw, 46px) clamp(20px, 4vw, 44px);
  border: 1px solid var(--hair);
  border-left: 3px solid var(--gold);
  border-radius: 3px;
  background: linear-gradient(160deg, rgba(22, 41, 92, .86), rgba(3, 6, 15, .94));
}

.page-about .cta-panel h2 {
  margin: 12px 0 14px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(24px, 3.6vw, 40px);
  line-height: 1.18;
  letter-spacing: -.015em;
  color: var(--chalk);
  max-width: 22ch;
}

.page-about .cta-text {
  margin: 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.82;
  color: var(--mist);
}

.page-about .cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

/* ---------- 断点 ---------- */
@media (min-width: 700px) {
  .page-about .net-points {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

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

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

@media (min-width: 860px) {
  .page-about .chapter-grid {
    grid-template-columns: var(--rail-col) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .chapter-rail {
    flex-direction: column;
    align-items: flex-start;
    gap: 20px;
    padding-top: 6px;
  }

  .page-about .chapter-rail-label {
    writing-mode: vertical-rl;
    text-orientation: upright;
    letter-spacing: .3em;
    line-height: 1;
  }

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

@media (min-width: 980px) {
  .page-about .hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: end;
  }

  .page-about .seq-grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
    align-items: center;
  }

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

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

@media (max-width: 420px) {
  .page-about .hero-stats {
    grid-template-columns: minmax(0, 1fr);
  }
}