.page-about {
  --about-rail: 200px;
  --about-gap: clamp(24px, 3.4vw, 56px);
  display: block;
  overflow-x: clip;
  background: var(--bs-night);
  color: var(--bs-text);
  font-family: var(--font-body);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  padding-block: clamp(22px, 3.4vw, 44px) clamp(34px, 5vw, 72px);
  background:
    radial-gradient(140% 110% at 94% -18%, rgba(31, 107, 74, 0.45), transparent 58%),
    linear-gradient(168deg, var(--bs-night) 0%, var(--bs-ink) 100%);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background: linear-gradient(112deg, transparent 45%, rgba(198, 255, 61, 0.06) 45.3%, rgba(198, 255, 61, 0.06) 51%, transparent 51.3%);
}

.page-about .about-hero-inner {
  display: grid;
  gap: clamp(24px, 3vw, 46px);
  margin-top: clamp(16px, 2.4vw, 28px);
}

.page-about .about-hero-copy .eyebrow {
  display: inline-block;
  margin: 0;
}

.page-about .about-hero h1 {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2rem, 5.6vw, 4.2rem);
  line-height: 1.04;
  letter-spacing: -0.04em;
}

.page-about .about-hl {
  color: var(--bs-action);
}

.page-about .about-lede {
  margin: 16px 0 0;
  max-width: 48ch;
  color: var(--bs-muted);
  font-size: var(--fs-body);
  line-height: 1.78;
}

.page-about .about-hero-media {
  position: relative;
  margin: 0;
  border: 1px solid var(--bs-line);
  border-radius: 2px 38px 2px 38px;
  overflow: hidden;
  box-shadow: 0 24px 56px rgba(6, 17, 29, 0.55);
}

.page-about .about-hero-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 14 / 9;
  object-fit: cover;
}

.page-about .about-hero-stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin-top: clamp(24px, 3.2vw, 42px);
  background: var(--bs-line);
  border-block: 1px solid var(--bs-line);
}

.page-about .about-stat {
  background: rgba(10, 26, 47, 0.88);
  padding: clamp(12px, 1.6vw, 20px) clamp(10px, 1.4vw, 20px);
  min-width: 0;
}

.page-about .about-stat b {
  display: block;
  font-family: var(--font-mono);
  font-weight: 800;
  font-size: clamp(1.2rem, 2.6vw, 2rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--bs-action);
}

.page-about .about-stat:nth-child(2) b {
  color: var(--bs-data);
}

.page-about .about-stat span {
  display: block;
  margin-top: 5px;
  font-size: 0.78rem;
  line-height: 1.5;
  color: var(--bs-muted);
}

/* ---------- 主体网格 ---------- */
.page-about .about-body {
  padding-block: clamp(34px, 4.6vw, 70px) clamp(40px, 5vw, 82px);
}

.page-about .about-canvas {
  min-width: 0;
}

/* ---------- 章节轨道 ---------- */
.page-about .about-track {
  position: sticky;
  top: 84px;
  align-self: start;
  min-width: 0;
}

.page-about .track-title {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  color: var(--bs-muted);
  text-transform: uppercase;
}

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

.page-about .about-track-link {
  display: grid;
  grid-template-columns: 26px minmax(0, 1fr);
  align-items: baseline;
  gap: 8px;
  padding: 9px 12px;
  border-left: 2px solid transparent;
  color: var(--bs-muted);
  text-decoration: none;
  font-size: 0.9rem;
  line-height: 1.4;
  transition: color 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.page-about .about-track-link:hover,
.page-about .about-track-link:focus-visible {
  color: var(--bs-text);
  border-left-color: var(--bs-action);
  background: linear-gradient(90deg, rgba(198, 255, 61, 0.12), transparent 80%);
}

.page-about .about-track-num {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--bs-action);
}

/* ---------- 章节通用 ---------- */
.page-about .about-chapter {
  scroll-margin-top: 88px;
}

.page-about .about-chapter + .about-chapter {
  margin-top: clamp(42px, 5.4vw, 88px);
}

.page-about .about-chapter:target .chapter-no {
  color: var(--bs-data);
}

.page-about .chapter-head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  border-bottom: 1px solid var(--bs-line);
  padding-bottom: 10px;
  margin-bottom: 16px;
}

.page-about .chapter-no {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 0.86rem;
  font-weight: 800;
  letter-spacing: 0.1em;
  color: var(--bs-action);
}

.page-about .chapter-head .section-title {
  margin: 0;
  flex: 1 1 auto;
  min-width: 0;
  line-height: 1.2;
}

.page-about .section-lede {
  max-width: 62ch;
}

/* ---------- 缘起 ---------- */
.page-about .about-quote {
  margin: clamp(20px, 2.6vw, 30px) 0;
  padding: clamp(16px, 2.2vw, 24px) clamp(16px, 2.4vw, 28px);
  border-left: 3px solid var(--bs-action);
  border-radius: 0 18px 0 0;
  background: linear-gradient(100deg, rgba(16, 42, 70, 0.9), rgba(10, 26, 47, 0.45));
}

.page-about .about-quote p {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.02rem, 1.5vw, 1.28rem);
  line-height: 1.6;
  letter-spacing: -0.01em;
  color: var(--bs-text);
}

.page-about .about-origin-grid {
  margin-top: clamp(18px, 2.4vw, 28px);
  gap: clamp(18px, 2.6vw, 34px);
}

.page-about .about-origin-grid .stack p {
  margin: 0 0 12px;
  color: var(--bs-muted);
  line-height: 1.8;
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: clamp(20px, 2.6vw, 30px) 0 0;
  padding: 0 0 0 22px;
  border-left: 1px solid var(--bs-line);
}

.page-about .tl-node {
  position: relative;
  padding-bottom: 14px;
}

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

.page-about .tl-node::before {
  content: "";
  position: absolute;
  left: -28px;
  top: 20px;
  width: 9px;
  height: 9px;
  background: var(--bs-action);
  transform: rotate(45deg);
  box-shadow: 0 0 0 4px rgba(198, 255, 61, 0.14);
}

.page-about .tl-item {
  border: 1px solid var(--bs-line);
  border-radius: 2px 18px 2px 18px;
  background: linear-gradient(150deg, rgba(16, 42, 70, 0.92), rgba(10, 26, 47, 0.62));
  overflow: hidden;
}

.page-about .tl-item[open] {
  border-color: var(--bs-action);
}

.page-about .tl-summary {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 12px;
  padding: 14px 16px;
  cursor: pointer;
  list-style: none;
}

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

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

.page-about .tl-year {
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--bs-data);
}

.page-about .tl-title {
  font-weight: 700;
  font-size: 1rem;
  color: var(--bs-text);
}

.page-about .tl-cue {
  font-family: var(--font-mono);
  font-size: 1.1rem;
  line-height: 1;
  color: var(--bs-action);
  transition: transform 0.22s ease;
}

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

.page-about .tl-body {
  padding: 0 16px 16px;
  border-top: 1px solid var(--bs-line);
}

.page-about .tl-body p {
  margin: 12px 0 0;
  color: var(--bs-muted);
  line-height: 1.78;
}

/* ---------- 团队 ---------- */
.page-about .about-crew {
  display: grid;
  gap: 14px;
  margin-top: clamp(20px, 2.6vw, 30px);
}

.page-about .crew-card {
  position: relative;
  padding: 20px 16px 22px;
  border: 1px solid var(--bs-line);
  border-radius: 2px 22px 2px 22px;
  background: linear-gradient(160deg, rgba(16, 42, 70, 0.96), rgba(10, 26, 47, 0.7));
  overflow: hidden;
  min-width: 0;
}

.page-about .crew-card::before {
  content: "";
  position: absolute;
  inset-inline: 0;
  top: 0;
  height: 3px;
  background: var(--bs-action);
}

.page-about .crew-card:nth-child(2)::before {
  background: var(--bs-data);
}

.page-about .crew-role {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.06rem;
  letter-spacing: 0.02em;
  color: var(--bs-text);
}

.page-about .crew-count {
  margin: 8px 0 0;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--bs-muted);
}

.page-about .crew-count span {
  font-size: 1.9rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--bs-action);
  margin-right: 4px;
}

.page-about .crew-card:nth-child(2) .crew-count span {
  color: var(--bs-data);
}

.page-about .crew-desc {
  margin: 10px 0 0;
  font-size: 0.92rem;
  line-height: 1.75;
  color: var(--bs-muted);
}

.page-about .about-crew-media {
  margin: clamp(22px, 3vw, 34px) 0 0;
}

.page-about .about-crew-media img,
.page-about .about-net-media img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--bs-line);
  border-radius: 2px 26px 2px 26px;
  object-fit: cover;
}

.page-about .media-caption {
  margin: 10px 0 0;
  font-size: 0.8rem;
  line-height: 1.6;
  color: var(--bs-muted);
}

/* ---------- 内容节奏 ---------- */
.page-about .about-rhythm {
  display: grid;
  gap: 12px;
  margin-top: clamp(20px, 2.6vw, 30px);
}

.page-about .rhythm-step {
  padding: 14px 16px;
  border-left: 3px solid var(--bs-line);
  background: linear-gradient(90deg, rgba(16, 42, 70, 0.78), rgba(10, 26, 47, 0.28));
  border-radius: 0 14px 0 0;
}

.page-about .rhythm-step:first-child {
  border-left-color: var(--bs-action);
}

.page-about .rhythm-step:last-child {
  border-left-color: var(--bs-data);
}

.page-about .rhythm-time {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--bs-text);
  background: rgba(198, 255, 61, 0.14);
  padding: 3px 9px;
  border-radius: 2px 10px 2px 10px;
}

.page-about .rhythm-step:last-child .rhythm-time {
  background: rgba(255, 107, 44, 0.16);
}

.page-about .rhythm-step p {
  margin: 9px 0 0;
  color: var(--bs-muted);
  line-height: 1.78;
}

.page-about .about-lines-title {
  margin: clamp(24px, 3vw, 34px) 0 10px;
  font-weight: 700;
  color: var(--bs-text);
}

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

.page-about .about-lines li {
  position: relative;
  padding: 12px 14px 12px 34px;
  font-size: 0.94rem;
  line-height: 1.75;
  color: var(--bs-muted);
  background: rgba(16, 42, 70, 0.42);
  border-radius: 2px 14px 2px 14px;
}

.page-about .about-lines li::before {
  content: "";
  position: absolute;
  left: 15px;
  top: 21px;
  width: 7px;
  height: 7px;
  background: var(--bs-action);
  transform: rotate(45deg);
}

.page-about .about-lines strong {
  color: var(--bs-text);
  font-weight: 700;
}

.page-about .about-lines-note {
  margin: 14px 0 18px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  letter-spacing: 0.01em;
  color: var(--bs-muted);
}

/* ---------- 城市网络 ---------- */
.page-about .net-wrap {
  margin-top: clamp(20px, 2.8vw, 32px);
  display: grid;
  gap: clamp(16px, 2.2vw, 26px);
}

.page-about .net-map {
  position: relative;
  aspect-ratio: 4 / 3;
  border: 1px solid var(--bs-line);
  border-radius: 2px 28px 2px 28px;
  background:
    linear-gradient(rgba(22, 62, 99, 0.4) 1px, transparent 1px) 0 0 / 100% 12.5%,
    linear-gradient(90deg, rgba(22, 62, 99, 0.4) 1px, transparent 1px) 0 0 / 10% 100%,
    radial-gradient(circle at 28% 22%, rgba(31, 107, 74, 0.5), transparent 58%),
    radial-gradient(circle at 76% 74%, rgba(22, 62, 99, 0.7), transparent 62%),
    var(--bs-panel);
  overflow: hidden;
}

.page-about .net-dot {
  position: absolute;
  width: 11px;
  height: 11px;
  margin: -5.5px 0 0 -5.5px;
  border-radius: 50%;
  background: var(--bs-action);
  box-shadow: 0 0 0 4px rgba(198, 255, 61, 0.16);
  z-index: 2;
}

.page-about .net-dot:focus-visible {
  outline: 2px solid var(--bs-focus);
  outline-offset: 6px;
}

.page-about .net-dot em {
  position: absolute;
  left: calc(100% + 10px);
  top: 50%;
  transform: translateY(-50%);
  white-space: nowrap;
  font-style: normal;
  font-size: 0.7rem;
  line-height: 1.3;
  padding: 4px 8px;
  color: var(--bs-text);
  background: var(--bs-ink);
  border: 1px solid var(--bs-action);
  border-radius: 2px 9px 2px 9px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.18s ease;
}

.page-about .net-dot--r em {
  left: auto;
  right: calc(100% + 10px);
}

.page-about .net-dot:hover em,
.page-about .net-dot:focus-visible em {
  opacity: 1;
}

.page-about .net-dot--1 { left: 14%; top: 26%; }
.page-about .net-dot--2 { left: 58%; top: 16%; }
.page-about .net-dot--3 { left: 36%; top: 44%; }
.page-about .net-dot--4 { left: 82%; top: 34%; }
.page-about .net-dot--5 { left: 22%; top: 66%; }
.page-about .net-dot--6 { left: 48%; top: 78%; }
.page-about .net-dot--7 { left: 78%; top: 62%; }
.page-about .net-dot--8 { left: 66%; top: 48%; }
.page-about .net-dot--9 { left: 30%; top: 88%; }

.page-about .net-facts {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--bs-line);
  border-block: 1px solid var(--bs-line);
}

.page-about .net-facts li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: baseline;
  gap: 14px;
  padding: 12px 14px;
  background: rgba(10, 26, 47, 0.86);
}

.page-about .net-facts b {
  font-family: var(--font-mono);
  font-size: clamp(1.2rem, 2vw, 1.5rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--bs-data);
  min-width: 3.4em;
}

.page-about .net-facts span {
  font-size: 0.88rem;
  line-height: 1.6;
  color: var(--bs-muted);
}

.page-about .about-net-media {
  margin: clamp(20px, 2.8vw, 30px) 0 0;
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  position: relative;
  padding-block: clamp(38px, 5vw, 76px);
  border-top: 1px solid var(--bs-line);
  background:
    linear-gradient(115deg, rgba(198, 255, 61, 0.07) 0%, transparent 42%),
    linear-gradient(180deg, var(--bs-ink), var(--bs-night));
}

.page-about .about-cta-inner {
  display: grid;
  gap: clamp(20px, 2.6vw, 34px);
}

.page-about .about-cta-title {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.4rem, 2.8vw, 2.2rem);
  line-height: 1.2;
  letter-spacing: -0.03em;
}

.page-about .about-cta-lede {
  margin: 12px 0 0;
  max-width: 54ch;
  color: var(--bs-muted);
  line-height: 1.78;
}

.page-about .about-cta-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 14px;
}

.page-about .about-cta-help {
  font-size: 0.86rem;
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-rhythm {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
  }

  .page-about .net-map {
    aspect-ratio: 16 / 9;
  }
}

@media (min-width: 860px) {
  .page-about .about-crew {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: clamp(14px, 1.8vw, 22px);
    padding-bottom: 56px;
  }

  .page-about .crew-card:nth-child(2) {
    transform: translateY(26px);
  }

  .page-about .crew-card:nth-child(3) {
    transform: translateY(52px);
  }

  .page-about .about-cta-inner {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    align-items: center;
  }

  .page-about .about-cta-actions {
    justify-content: flex-start;
  }
}

@media (min-width: 920px) {
  .page-about .about-hero-inner {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    align-items: end;
  }
}

@media (min-width: 1000px) {
  .page-about .about-body {
    display: grid;
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: var(--about-gap);
    align-items: start;
  }

  .page-about .net-wrap {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, 0.75fr);
    align-items: stretch;
  }

  .page-about .net-facts {
    border: 1px solid var(--bs-line);
    border-radius: 2px 22px 2px 22px;
    align-content: center;
  }
}

@media (max-width: 999px) {
  .page-about .about-track {
    position: static;
  }

  .page-about .track-title {
    margin-bottom: 8px;
  }

  .page-about .about-track-list {
    display: flex;
    gap: 8px;
    overflow-x: auto;
    padding-bottom: 6px;
    scrollbar-width: thin;
  }

  .page-about .about-track-link {
    flex: 0 0 auto;
    white-space: nowrap;
    grid-template-columns: auto auto;
    border-left: none;
    border-bottom: 2px solid transparent;
    border-radius: 2px 14px 2px 14px;
    background: var(--bs-panel);
    padding: 8px 12px;
  }

  .page-about .about-track-link:hover,
  .page-about .about-track-link:focus-visible {
    border-left: none;
    border-bottom-color: var(--bs-action);
    background: linear-gradient(180deg, rgba(198, 255, 61, 0.16), rgba(16, 42, 70, 0.9));
  }

  .page-about .about-canvas {
    margin-top: clamp(20px, 3vw, 28px);
  }
}

@media (max-width: 520px) {
  .page-about .about-stat span {
    font-size: 0.7rem;
  }

  .page-about .net-facts li {
    grid-template-columns: minmax(0, 1fr);
    gap: 4px;
  }

  .page-about .net-facts b {
    min-width: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-track-link,
  .page-about .tl-cue,
  .page-about .net-dot em {
    transition: none;
  }
}