.page-about {
  --ab-rail-w: 200px;
  --ab-grid-line: rgba(70, 217, 255, 0.07);
}

.page-about .ab-mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

/* ===== 开篇 ===== */
.page-about .ab-top {
  position: relative;
  padding-block: 2rem 2.6rem;
  color: var(--paper);
  overflow: hidden;
}

.page-about .ab-top::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    repeating-linear-gradient(90deg, var(--ab-grid-line) 0 1px, transparent 1px 96px),
    radial-gradient(120% 90% at 84% -10%, rgba(163, 255, 60, 0.1), transparent 60%),
    radial-gradient(90% 70% at 0% 100%, rgba(255, 122, 26, 0.08), transparent 62%);
  pointer-events: none;
}

.page-about .ab-top > .wrap {
  position: relative;
  z-index: 1;
}

.page-about .ab-hero-grid {
  display: grid;
  gap: 2.2rem;
  margin-top: 1.6rem;
}

.page-about .ab-title {
  font-family: var(--font-display);
  font-size: clamp(2.05rem, 6.4vw, 4rem);
  line-height: 1.02;
  letter-spacing: -0.015em;
  margin: 0.7rem 0 1.1rem;
  color: var(--paper);
  text-wrap: balance;
}

.page-about .ab-hero-main .lede {
  font-family: var(--font-serif);
  font-size: clamp(1rem, 1.6vw, 1.12rem);
  line-height: 1.8;
  max-width: 34em;
  color: rgba(244, 235, 221, 0.88);
  margin: 0;
}

.page-about .ab-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 2.2rem;
  margin-top: 1.8rem;
  padding-top: 1.2rem;
  border-top: 1px solid var(--line);
}

.page-about .ab-meta-item {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  min-width: 6.5rem;
}

.page-about .ab-meta-num {
  font-family: var(--font-mono);
  font-size: 1.12rem;
  letter-spacing: 0.02em;
  color: var(--lime);
  line-height: 1.2;
}

.page-about .ab-meta-cap {
  font-size: 0.75rem;
  line-height: 1.5;
  color: var(--mist);
}

.page-about .ab-toc {
  align-self: end;
}

.page-about .ab-toc-cap {
  font-family: var(--font-serif);
  font-size: 0.82rem;
  letter-spacing: 0.22em;
  color: var(--mist);
  margin: 0 0 0.6rem;
}

.page-about .ab-toc ol {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .ab-toc li {
  border-bottom: 1px solid var(--line);
}

.page-about .ab-toc a {
  display: flex;
  align-items: baseline;
  gap: 0.9rem;
  padding: 0.72rem 0;
  color: var(--paper);
  text-decoration: none;
  font-size: 0.94rem;
  line-height: 1.5;
  transition: transform 0.22s var(--ease), color 0.22s var(--ease);
}

.page-about .ab-toc a .ab-mono {
  font-size: 0.78rem;
  color: var(--mist);
  letter-spacing: 0.08em;
  transition: color 0.22s var(--ease);
}

.page-about .ab-toc a:hover,
.page-about .ab-toc a:focus-visible {
  transform: translateX(4px);
  color: var(--lime);
}

.page-about .ab-toc a:hover .ab-mono,
.page-about .ab-toc a:focus-visible .ab-mono {
  color: var(--lime);
}

/* ===== 章节骨架 ===== */
.page-about .ab-sec {
  scroll-margin-top: 5.5rem;
}

.page-about .ab-chapter {
  display: grid;
  gap: 1.4rem;
}

.page-about .ab-rail {
  display: flex;
  align-items: baseline;
  gap: 0.9rem;
}

.page-about .ab-num {
  font-family: var(--font-mono);
  font-size: clamp(2.6rem, 8vw, 4.4rem);
  line-height: 1;
  letter-spacing: -0.02em;
  opacity: 0.16;
  color: currentColor;
}

.page-about .ab-year {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.16em;
  color: var(--cyan);
  white-space: nowrap;
}

.page-about .surface-paper .ab-year {
  color: rgba(16, 24, 32, 0.72);
  padding-left: 0.7rem;
  border-left: 3px solid var(--orange);
}

.page-about .ab-ch-title {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 4vw, 2.35rem);
  line-height: 1.14;
  letter-spacing: -0.01em;
  margin: 0 0 0.7rem;
  color: var(--paper);
}

.page-about .surface-paper .ab-ch-title {
  color: var(--ink-text);
}

.page-about .ab-ch-lede {
  font-family: var(--font-serif);
  font-size: 1.02rem;
  line-height: 1.8;
  max-width: 32em;
  margin: 0 0 1.5rem;
  color: rgba(244, 235, 221, 0.86);
}

.page-about .surface-paper .ab-ch-lede {
  color: rgba(16, 24, 32, 0.82);
}

.page-about .ab-body p {
  max-width: 34em;
  line-height: 1.85;
  font-size: 0.96rem;
  color: rgba(244, 235, 221, 0.8);
  margin: 0 0 1rem;
}

.page-about .surface-paper .ab-body p {
  color: rgba(16, 24, 32, 0.8);
}

.page-about .ab-body .btn-link {
  color: var(--cyan);
}

.page-about .surface-paper .ab-body .btn-link {
  color: var(--ink-text);
  text-decoration-color: var(--orange);
}

/* ===== 图文组合 ===== */
.page-about .ab-figrow {
  display: grid;
  gap: 1.4rem;
  margin: 1.4rem 0 1.8rem;
}

.page-about .ab-fig {
  margin: 0;
}

.page-about .ab-fig .figure-media {
  border: 1px solid var(--line);
  border-radius: 4px;
  overflow: hidden;
  background: var(--ink-2);
}

.page-about .surface-paper .ab-fig .figure-media {
  border-color: rgba(16, 24, 32, 0.16);
  background: rgba(16, 24, 32, 0.06);
}

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

.page-about .ab-fig .figure-cap {
  margin-top: 0.6rem;
  font-size: 0.78rem;
  line-height: 1.6;
  color: var(--mist);
}

.page-about .surface-paper .ab-fig .figure-cap {
  color: rgba(16, 24, 32, 0.6);
}

/* ===== 数字 ===== */
.page-about .ab-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 1.4rem 2.6rem;
  margin: 0 0 1.6rem;
  padding-bottom: 1.2rem;
  border-bottom: 1px solid var(--line);
}

.page-about .ab-stat {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.page-about .ab-stat .stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(2rem, 5.4vw, 3rem);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--lime);
}

.page-about .ab-stat .stat-cap {
  font-size: 0.78rem;
  line-height: 1.5;
  color: var(--mist);
}

/* ===== 四组分工 ===== */
.page-about .ab-crew {
  display: grid;
  gap: 1px;
  margin-top: 1.4rem;
  border: 1px solid var(--line);
  background: var(--line);
  border-radius: 4px;
  overflow: hidden;
}

.page-about .ab-crew-item {
  background: var(--ink-2);
  padding: 1.1rem 1.2rem;
}

.page-about .ab-crew-item h3 {
  font-family: var(--font-body);
  font-size: 0.92rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--lime);
  margin: 0 0 0.35rem;
}

.page-about .ab-crew-item p {
  margin: 0;
  max-width: none;
  font-size: 0.86rem;
  line-height: 1.72;
  color: var(--mist);
}

/* ===== 对照维度 ===== */
.page-about .ab-dims {
  list-style: none;
  margin: 1.2rem 0 1.4rem;
  padding: 0;
  border-top: 1px solid rgba(16, 24, 32, 0.2);
}

.page-about .ab-dims li {
  display: grid;
  grid-template-columns: 4.6rem 1fr;
  gap: 0.9rem;
  padding: 0.85rem 0;
  border-bottom: 1px solid rgba(16, 24, 32, 0.14);
}

.page-about .ab-dims b {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--ink-text);
  padding-top: 0.1rem;
}

.page-about .ab-dims span {
  font-size: 0.92rem;
  line-height: 1.72;
  color: rgba(16, 24, 32, 0.78);
}

.page-about .ab-body p.ab-side {
  font-family: var(--font-serif);
  font-size: 0.98rem;
  line-height: 1.82;
  color: rgba(16, 24, 32, 0.86);
  padding-left: 1rem;
  border-left: 2px solid var(--orange);
}

/* ===== 时间线 ===== */
.page-about .ab-tl {
  list-style: none;
  margin: 1.4rem 0 0;
  padding: 0;
}

.page-about .ab-tl li {
  position: relative;
  padding: 0 0 1.4rem 1.5rem;
  border-left: 1px solid var(--line);
}

.page-about .ab-tl li:last-child {
  padding-bottom: 0.2rem;
}

.page-about .ab-tl li::before {
  content: "";
  position: absolute;
  left: -4px;
  top: 0.4rem;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--lime);
}

.page-about .ab-tl li:focus {
  outline: none;
}

.page-about .ab-tl li:focus-visible {
  outline: 1px solid var(--cyan);
  outline-offset: 4px;
}

.page-about .ab-tl .ab-mono {
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  color: var(--cyan);
}

.page-about .ab-tl h3 {
  font-family: var(--font-body);
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.4;
  margin: 0.2rem 0 0.3rem;
  color: var(--paper);
}

.page-about .ab-tl-note {
  margin: 0;
  max-width: 34em;
  font-size: 0.88rem;
  line-height: 1.72;
  color: var(--mist);
}

/* ===== 规模 ===== */
.page-about .ab-scale {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0 0 1.6rem;
  background: rgba(16, 24, 32, 0.16);
  border: 1px solid rgba(16, 24, 32, 0.16);
  border-radius: 4px;
  overflow: hidden;
}

.page-about .ab-scale-item {
  background: var(--paper);
  padding: 1.1rem 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.page-about .ab-scale-num {
  font-family: var(--font-mono);
  font-size: clamp(1.4rem, 4vw, 2rem);
  line-height: 1.1;
  letter-spacing: -0.01em;
  color: var(--ink-text);
}

.page-about .ab-scale-cap {
  font-size: 0.78rem;
  line-height: 1.5;
  color: rgba(16, 24, 32, 0.62);
}

/* ===== 服务承诺 ===== */
.page-about .ab-promise .ab-body p {
  max-width: 32em;
}

.page-about .ab-promise-grid {
  display: grid;
  gap: 1.6rem;
  margin-top: 0.4rem;
}

.page-about .ab-promise-item {
  padding-bottom: 1.1rem;
  margin-bottom: 1.1rem;
  border-bottom: 1px solid var(--line);
}

.page-about .ab-promise-item:last-child {
  border-bottom: none;
  margin-bottom: 0;
}

.page-about .ab-promise-item h3 {
  font-family: var(--font-body);
  font-size: 0.98rem;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--lime);
  margin: 0 0 0.4rem;
}

.page-about .ab-promise-item p {
  margin: 0;
}

.page-about .ab-contact {
  border: 1px solid var(--line);
  border-radius: 4px;
  padding: 1.3rem 1.2rem;
  background: var(--ink-2);
  box-shadow: var(--shadow-soft);
}

.page-about .ab-contact-label {
  margin: 0;
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--mist);
}

.page-about .ab-contact-value {
  margin: 0.15rem 0 0.95rem;
  font-size: 0.95rem;
  line-height: 1.6;
  color: var(--paper);
  word-break: break-word;
}

.page-about .ab-contact-value:last-child {
  margin-bottom: 0;
}

.page-about .ab-contact-addr {
  font-size: 0.9rem;
}

.page-about .ab-contact .ab-mono {
  letter-spacing: 0.02em;
  color: var(--lime);
}

.page-about .ab-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin-top: 1.8rem;
}

/* ===== 响应式 ===== */
@media (min-width: 620px) {
  .page-about .ab-crew {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .page-about .ab-dims li {
    grid-template-columns: 6rem 1fr;
  }
}

@media (min-width: 900px) {
  .page-about .ab-hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: clamp(2rem, 5vw, 4rem);
    align-items: stretch;
  }

  .page-about .ab-toc {
    border-left: 1px solid var(--line);
    padding-left: clamp(1.4rem, 3vw, 2.2rem);
  }

  .page-about .ab-chapter {
    grid-template-columns: var(--ab-rail-w) minmax(0, 1fr);
    gap: clamp(1.8rem, 4vw, 3.4rem);
  }

  .page-about .ab-rail {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
    position: sticky;
    top: 6.5rem;
  }

  .page-about .ab-figrow {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: 1.8rem;
    align-items: start;
  }

  .page-about .ab-figrow-rev {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }

  .page-about .ab-promise-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: clamp(1.8rem, 4vw, 3rem);
    align-items: start;
  }
}

@media (min-width: 900px) and (hover: hover) {
  .page-about .ab-tl-note {
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    transition: max-height 0.3s var(--ease), opacity 0.24s var(--ease), margin 0.24s var(--ease);
    margin-top: 0;
  }

  .page-about .ab-tl li:hover .ab-tl-note,
  .page-about .ab-tl li:focus .ab-tl-note,
  .page-about .ab-tl li:focus-within .ab-tl-note {
    max-height: 9rem;
    opacity: 1;
    margin-top: 0.2rem;
  }

  .page-about .ab-tl li ::before {
    transition: transform 0.22s var(--ease);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-toc a,
  .page-about .ab-tl-note {
    transition: none;
  }

  .page-about .ab-toc a:hover,
  .page-about .ab-toc a:focus-visible {
    transform: none;
  }
}
<<<END>>>