.page-about {
  --pa-gap: clamp(20px, 3vw, 32px);
  --pa-band: clamp(52px, 7vw, 96px);
  display: block;
  font-family: var(--bl-font-body);
  color: var(--bl-mist-100);
  background: var(--bl-navy-900);
}

.page-about .pa-canvas {
  position: relative;
  background-color: var(--bl-navy-900);
  background-image:
    radial-gradient(110% 46% at 8% -4%, rgba(107, 79, 224, .20), transparent 62%),
    radial-gradient(78% 40% at 96% 3%, rgba(47, 227, 208, .09), transparent 68%),
    linear-gradient(to right, rgba(47, 227, 208, .055) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(47, 227, 208, .055) 1px, transparent 1px);
  background-size: auto, auto, 92px 92px, 92px 92px;
  background-repeat: no-repeat, no-repeat, repeat, repeat;
}

/* ---------- 面包屑 ---------- */
.page-about .pa-crumb {
  max-width: var(--bl-wrap);
  margin: 0 auto;
  padding: clamp(22px, 3vw, 38px) var(--bl-edge) 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  font-family: var(--bl-font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--bl-slate-400);
}

.page-about .pa-crumb-sep {
  color: var(--bl-cyan-600);
}

/* ---------- 首屏 ---------- */
.page-about .pa-hero {
  max-width: var(--bl-wrap);
  margin: 0 auto;
  padding: clamp(28px, 4vw, 56px) var(--bl-edge) clamp(44px, 6vw, 84px);
  display: grid;
  gap: var(--pa-gap);
}

.page-about .pa-hero-inner {
  display: flex;
  flex-direction: column;
}

.page-about .pa-hero-title {
  margin: 16px 0 0;
  font-family: var(--bl-font-display);
  font-weight: 250;
  font-size: clamp(29px, 5.2vw, 58px);
  line-height: 1.2;
  letter-spacing: .04em;
  color: var(--bl-mist-100);
}

.page-about .pa-hero-lede {
  margin: clamp(18px, 2.4vw, 28px) 0 0;
  max-width: 60ch;
  font-size: clamp(16px, 1.45vw, 19px);
  line-height: 1.85;
  color: var(--bl-slate-400);
}

.page-about .pa-hero-facts {
  margin: clamp(26px, 3.6vw, 44px) 0 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 1px;
  background: var(--bl-line-soft);
  border: 1px solid var(--bl-line-soft);
  border-radius: var(--bl-radius);
  overflow: hidden;
}

.page-about .pa-hero-facts > div {
  background: rgba(11, 33, 56, .78);
  padding: 18px 20px;
}

.page-about .pa-hero-facts dt {
  font-family: var(--bl-font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--bl-cyan-600);
}

.page-about .pa-hero-facts dd {
  margin: 10px 0 0;
  font-family: var(--bl-font-display);
  font-weight: 300;
  font-size: clamp(22px, 2.6vw, 30px);
  letter-spacing: .04em;
  color: var(--bl-mist-100);
}

.page-about .pa-hero-figure {
  margin: 0;
}

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

.page-about .pa-hero-figure figcaption {
  padding: 12px 16px 14px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--bl-slate-400);
  border-top: 1px solid var(--bl-line-soft);
}

/* ---------- 章节索引 ---------- */
.page-about .pa-index {
  max-width: var(--bl-wrap);
  margin: 0 auto;
  padding: 0 var(--bl-edge) clamp(40px, 6vw, 76px);
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .pa-index-link {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 9px 15px;
  border: 1px solid var(--bl-line);
  border-radius: 999px;
  font-size: 13px;
  line-height: 1.4;
  color: var(--bl-mist-100);
  text-decoration: none;
  background: rgba(18, 49, 84, .5);
  transition: border-color .24s var(--bl-ease), transform .24s var(--bl-ease), color .24s var(--bl-ease);
}

.page-about .pa-index-link:hover,
.page-about .pa-index-link:focus-visible {
  border-color: var(--bl-orange-500);
  color: var(--bl-gold-300);
  transform: translateX(4px);
}

.page-about .pa-index-no {
  font-family: var(--bl-font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--bl-cyan-400);
}

/* ---------- 章节骨架 ---------- */
.page-about .pa-section {
  position: relative;
  max-width: var(--bl-wrap);
  margin: 0 auto;
  padding: 0 var(--bl-edge) var(--pa-band);
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
}

.page-about .pa-rail {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--bl-font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--bl-cyan-400);
}

.page-about .pa-rail::before {
  content: "";
  width: 7px;
  height: 7px;
  flex: none;
  border-radius: 50%;
  border: 1px solid var(--bl-cyan-400);
  background: rgba(47, 227, 208, .2);
  box-shadow: 0 0 0 4px rgba(47, 227, 208, .07);
}

.page-about .pa-h2 {
  margin: 12px 0 0;
  font-family: var(--bl-font-display);
  font-weight: 300;
  font-size: clamp(23px, 3.2vw, 38px);
  line-height: 1.32;
  letter-spacing: .05em;
  color: var(--bl-mist-100);
}

.page-about .pa-prose {
  margin-top: clamp(16px, 2vw, 24px);
}

.page-about .pa-prose p,
.page-about .pa-prose-first,
.page-about .pa-prose-last {
  margin: 0 0 1em;
  font-size: clamp(15px, 1.35vw, 17px);
  line-height: 1.85;
  color: var(--bl-slate-400);
}

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

.page-about .pa-prose-first {
  margin-top: clamp(16px, 2vw, 24px);
}

.page-about .pa-prose-last {
  margin-top: clamp(22px, 3vw, 32px);
}

/* ---------- 旁注 ---------- */
.page-about .pa-side {
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--bl-slate-400);
}

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

.page-about .pa-note {
  border-left: 2px solid var(--bl-line-strong);
  padding: 4px 0 4px 16px;
}

.page-about .pa-note-title {
  margin: 0 0 10px;
  font-family: var(--bl-font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--bl-gold-300);
}

.page-about .pa-note p {
  margin: 0 0 .8em;
}

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

.page-about .pa-note-strong {
  font-family: var(--bl-font-mono);
  font-size: 26px;
  letter-spacing: .06em;
  color: var(--bl-cyan-400);
}

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

.page-about .pa-note-list li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding: 7px 0;
  border-bottom: 1px dashed var(--bl-line-soft);
}

.page-about .pa-note-list li:last-child {
  border-bottom: 0;
}

.page-about .pa-note-list b {
  font-family: var(--bl-font-mono);
  font-weight: 400;
  font-size: 15px;
  letter-spacing: .04em;
  color: var(--bl-cyan-400);
}

/* ---------- 时间轴 ---------- */
.page-about .pa-timeline {
  list-style: none;
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 0 0 0 clamp(18px, 2.6vw, 30px);
  border-left: 1px solid var(--bl-line);
}

.page-about .pa-tl-item {
  position: relative;
  padding-bottom: clamp(6px, 1.4vw, 14px);
}

.page-about .pa-tl-item::before {
  content: "";
  position: absolute;
  left: calc(-1 * clamp(18px, 2.6vw, 30px) - 4px);
  top: 20px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  border: 1px solid var(--bl-cyan-400);
  background: var(--bl-navy-900);
}

.page-about .pa-tl-item:last-child::before {
  border-color: var(--bl-orange-500);
  background: rgba(255, 138, 61, .35);
}

.page-about .pa-tl-year {
  display: block;
  font-family: var(--bl-font-mono);
  font-size: 13px;
  letter-spacing: .18em;
  color: var(--bl-cyan-600);
  padding-top: 14px;
}

.page-about .pa-tl-detail {
  border-bottom: 1px solid var(--bl-line-soft);
}

.page-about .pa-tl-summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 12px 0 14px;
  font-family: var(--bl-font-display);
  font-weight: 300;
  font-size: clamp(17px, 1.9vw, 22px);
  letter-spacing: .05em;
  color: var(--bl-mist-100);
  transition: color .24s var(--bl-ease);
}

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

.page-about .pa-tl-summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--bl-font-mono);
  font-size: 15px;
  line-height: 1;
  color: var(--bl-cyan-400);
}

.page-about .pa-tl-detail[open] .pa-tl-summary::after {
  content: "–";
}

.page-about .pa-tl-summary:hover {
  color: var(--bl-gold-300);
}

.page-about .pa-tl-text {
  margin: 0 0 16px;
  max-width: 56ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--bl-slate-400);
}

.page-about .pa-tl-figure,
.page-about .pa-partner-figure {
  margin: 0;
}

.page-about .pa-tl-figure img,
.page-about .pa-partner-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .pa-tl-figure figcaption,
.page-about .pa-partner-figure figcaption {
  padding: 12px 16px 14px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--bl-slate-400);
  border-top: 1px solid var(--bl-line-soft);
}

/* ---------- 团队分工条形 ---------- */
.page-about .pa-bars {
  list-style: none;
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 0;
  display: grid;
  gap: clamp(16px, 2.2vw, 24px);
}

.page-about .pa-bar-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
}

.page-about .pa-bar-label {
  font-family: var(--bl-font-display);
  font-weight: 300;
  font-size: clamp(16px, 1.7vw, 20px);
  letter-spacing: .06em;
  color: var(--bl-mist-100);
}

.page-about .pa-bar-num {
  font-family: var(--bl-font-mono);
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--bl-cyan-400);
}

.page-about .pa-bar-track {
  margin-top: 10px;
  height: 8px;
  border-radius: 999px;
  background: var(--bl-navy-700);
  overflow: hidden;
}

.page-about .pa-bar-fill {
  display: block;
  height: 100%;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--bl-cyan-600), var(--bl-cyan-400));
  transition: background .3s var(--bl-ease);
}

.page-about .pa-bar--content .pa-bar-fill {
  width: 38%;
}

.page-about .pa-bar--data .pa-bar-fill {
  width: 26%;
}

.page-about .pa-bar--service .pa-bar-fill {
  width: 21%;
  background: linear-gradient(90deg, var(--bl-violet-500), var(--bl-cyan-400));
}

.page-about .pa-bar--quality .pa-bar-fill {
  width: 14%;
  background: linear-gradient(90deg, var(--bl-wine-600), var(--bl-gold-300));
}

.page-about .pa-bar:hover .pa-bar-fill {
  background: linear-gradient(90deg, var(--bl-orange-500), var(--bl-gold-300));
}

.page-about .pa-bar-note {
  margin: 10px 0 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--bl-slate-400);
}

/* ---------- 四个入口 ---------- */
.page-about .pa-gates {
  list-style: none;
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--bl-line-soft);
  border: 1px solid var(--bl-line-soft);
  border-radius: var(--bl-radius);
  overflow: hidden;
}

.page-about .pa-gate {
  padding: clamp(20px, 2.6vw, 28px);
  background: rgba(11, 33, 56, .82);
  transition: background .26s var(--bl-ease);
}

.page-about .pa-gate:hover {
  background: rgba(18, 49, 84, .9);
}

.page-about .pa-gate-no {
  display: block;
  font-family: var(--bl-font-mono);
  font-size: 11px;
  letter-spacing: .2em;
  color: var(--bl-cyan-600);
}

.page-about .pa-gate-title {
  margin: 10px 0 0;
  font-family: var(--bl-font-display);
  font-weight: 300;
  font-size: clamp(17px, 1.8vw, 21px);
  letter-spacing: .06em;
  color: var(--bl-mist-100);
}

.page-about .pa-gate-text {
  margin: 10px 0 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--bl-slate-400);
}

.page-about .pa-gate-link {
  display: inline-block;
  margin-top: 12px;
  font-size: 14px;
}

/* ---------- 更新节奏 ---------- */
.page-about .pa-cadence {
  list-style: none;
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .pa-cadence-item {
  display: grid;
  gap: 8px;
  padding: 16px 18px;
  border: 1px solid var(--bl-line-soft);
  border-radius: var(--bl-radius);
  background: rgba(11, 33, 56, .58);
}

.page-about .pa-cadence-cycle {
  font-family: var(--bl-font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--bl-orange-500);
}

.page-about .pa-cadence-item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--bl-slate-400);
}

/* ---------- 合作生态 ---------- */
.page-about .pa-section--partner .pa-h2 {
  color: var(--bl-mist-100);
}

.page-about .pa-section--partner .pa-rail::before {
  border-color: var(--bl-violet-500);
  background: rgba(107, 79, 224, .28);
  box-shadow: 0 0 0 4px rgba(107, 79, 224, .12);
}

.page-about .pa-section--partner .pa-rail-no {
  color: var(--bl-violet-500);
}

/* ---------- 运营数据 ---------- */
.page-about .pa-stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .pa-stats li {
  padding-left: 16px;
  border-left: 2px solid var(--bl-line-strong);
}

.page-about .pa-stats b {
  display: block;
  font-family: var(--bl-font-mono);
  font-weight: 400;
  font-size: clamp(20px, 2.4vw, 26px);
  letter-spacing: .04em;
  color: var(--bl-cyan-400);
}

.page-about .pa-stats span {
  display: block;
  margin-top: 4px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--bl-slate-400);
}

/* ---------- 联系收尾 ---------- */
.page-about .pa-section--contact {
  padding-bottom: clamp(64px, 9vw, 120px);
}

.page-about .pa-section--contact .pa-body--full {
  padding: clamp(26px, 4vw, 44px);
  border: 1px solid var(--bl-line);
  border-radius: var(--bl-radius);
  background:
    linear-gradient(135deg, rgba(47, 227, 208, .10), transparent 52%),
    rgba(11, 33, 56, .8);
}

.page-about .pa-cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: clamp(22px, 3vw, 30px) 0 0;
}

/* ---------- 桌面栅格 ---------- */
@media (min-width: 62em) {
  .page-about .pa-hero {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: 24px;
  }

  .page-about .pa-hero-inner {
    grid-column: 1 / span 12;
  }

  .page-about .pa-hero-figure {
    grid-column: 4 / span 9;
    margin-top: clamp(20px, 3vw, 44px);
  }

  .page-about .pa-section {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: 24px;
    row-gap: 0;
  }

  .page-about .pa-section::before {
    content: "";
    position: absolute;
    left: calc(var(--bl-edge) + 3px);
    top: 34px;
    bottom: 0;
    width: 1px;
    background: linear-gradient(180deg, var(--bl-line), transparent 88%);
  }

  .page-about .pa-rail {
    grid-column: 1 / span 1;
    align-self: start;
    position: sticky;
    top: calc(var(--bl-header-h) + 28px);
    writing-mode: vertical-rl;
    display: block;
    padding-top: 0;
    letter-spacing: .32em;
  }

  .page-about .pa-rail::before {
    display: none;
  }

  .page-about .pa-body {
    grid-column: 2 / span 8;
  }

  .page-about .pa-section--narrow .pa-body {
    grid-column: 2 / span 5;
  }

  .page-about .pa-section--narrow .pa-side {
    grid-column: 8 / span 5;
  }

  .page-about .pa-side {
    grid-column: 10 / span 3;
  }

  .page-about .pa-section--timeline .pa-body {
    grid-column: 2 / span 7;
  }

  .page-about .pa-section--timeline .pa-side {
    grid-column: 9 / span 4;
  }

  .page-about .pa-section--partner .pa-body {
    grid-column: 2 / span 7;
  }

  .page-about .pa-section--partner .pa-side {
    grid-column: 9 / span 4;
  }

  .page-about .pa-section--contact .pa-body--full {
    grid-column: 2 / span 11;
  }

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

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

@media (min-width: 90em) {
  .page-about .pa-gates {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (max-width: 61.99em) {
  .page-about .pa-side {
    margin-top: 6px;
  }

  .page-about .pa-section--timeline .pa-side--figure {
    order: -1;
  }
}

@media (max-width: 30em) {
  .page-about .pa-index-link {
    padding: 8px 12px;
    font-size: 12.5px;
  }

  .page-about .pa-hero-facts > div {
    padding: 14px 16px;
  }

  .page-about .pa-gate {
    padding: 18px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .pa-index-link,
  .page-about .pa-bar-fill,
  .page-about .pa-tl-summary,
  .page-about .pa-gate {
    transition: none;
  }
}