.page-about {
  --about-hair: rgba(43, 232, 200, 0.2);
  --about-rule: 1px solid var(--about-hair);
  --about-gap: clamp(3rem, 7vw, 6rem);
  padding-block: clamp(1.5rem, 4vw, 3rem) clamp(3.5rem, 8vw, 6rem);
  overflow-x: clip;
}

.page-about .sec {
  margin-block-start: var(--about-gap);
}

/* ---------- 页头 ---------- */

.page-about .about-head {
  display: grid;
  gap: 1.15rem;
  padding-block-start: clamp(0.5rem, 2vw, 1.5rem);
}

.page-about .eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  color: var(--cyan-dim);
}

.page-about .about-head h1 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2rem, 5.6vw, 3.85rem);
  line-height: 1.06;
  letter-spacing: 0.01em;
  color: var(--paper);
  max-width: 24ch;
}

.page-about .about-head__lede {
  margin: 0;
  max-width: 58ch;
  color: var(--mist);
  font-size: clamp(0.975rem, 1.4vw, 1.0625rem);
  line-height: 1.85;
}

.page-about .about-ledger {
  display: grid;
  gap: 1.25rem;
  margin-block-start: 0.5rem;
}

.page-about .about-ledger .stat {
  border-inline-start: 2px solid var(--cyan);
  padding-inline-start: 0.95rem;
}

.page-about .about-ledger .stat--signal {
  border-inline-start-color: var(--orange);
}

.page-about .stat__value {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.6rem, 3.6vw, 2.35rem);
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--cyan);
}

.page-about .stat__value--signal {
  color: var(--orange);
}

.page-about .stat__label {
  display: block;
  margin-block-start: 0.45rem;
  font-size: 0.8125rem;
  letter-spacing: 0.06em;
  color: var(--mute);
}

/* ---------- 章节头 ---------- */

.page-about .chapter__head {
  display: grid;
  gap: 0.45rem;
  align-items: center;
  margin-block-end: 1.65rem;
}

.page-about .chapter__num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(2.8rem, 8vw, 5.5rem);
  line-height: 0.82;
  color: transparent;
  -webkit-text-stroke: 1.5px var(--cyan);
  opacity: 0.78;
}

.page-about .chapter__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.45rem, 3.2vw, 2.1rem);
  line-height: 1.16;
  letter-spacing: 0.01em;
  color: var(--paper);
  max-width: 30ch;
}

.page-about .sub-title {
  margin: 0 0 0.9rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  color: var(--cyan-dim);
}

.page-about .sec__lede {
  margin: 0 0 1.5rem;
  max-width: 56ch;
  color: var(--mist);
  font-size: 0.975rem;
  line-height: 1.85;
}

.page-about .sec__foot {
  margin: 1.75rem 0 0;
  max-width: 56ch;
  color: var(--mist);
  font-size: 0.9125rem;
  line-height: 1.8;
  padding-inline-start: 1rem;
  border-inline-start: 2px solid var(--cyan);
}

/* ---------- 正文 ---------- */

.page-about .prose p {
  margin: 0 0 1rem;
  color: var(--mist);
  font-size: 1rem;
  line-height: 1.85;
}

.page-about .prose p:last-child {
  margin-block-end: 0;
}

/* ---------- 01 起点 ---------- */

.page-about .origin-grid {
  display: grid;
  gap: 1.75rem;
}

.page-about .paper-note {
  background: var(--paper);
  color: var(--paper-ink);
  border-radius: var(--radius-l);
  padding: clamp(1.5rem, 4vw, 2.6rem);
}

.page-about .paper-note__tag {
  display: inline-block;
  margin-block-end: 0.9rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  color: var(--paper-ink);
  opacity: 0.62;
}

.page-about .paper-note p {
  margin: 0 0 1rem;
  font-size: clamp(0.95rem, 1.3vw, 1.05rem);
  line-height: 1.9;
}

.page-about .paper-note p:last-child {
  margin-block-end: 0;
}

/* ---------- 图片 ---------- */

.page-about .about-shot {
  margin: 0;
  border-radius: var(--radius-l);
  overflow: hidden;
  background: var(--raise);
  border: var(--about-rule);
}

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

.page-about .about-shot figcaption {
  padding: 0.7rem 1rem;
  font-size: 0.78rem;
  letter-spacing: 0.05em;
  line-height: 1.6;
  color: var(--mist);
  background: var(--board);
  border-block-start: var(--about-rule);
}

/* ---------- 02 流程 ---------- */

.page-about .about-shot--wide {
  margin-block-end: 1.75rem;
}

.page-about .flow {
  display: grid;
  gap: 1rem;
}

.page-about .step {
  background: var(--board);
  border: var(--about-rule);
  border-radius: var(--radius-m);
  padding: 1.1rem 1.2rem;
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .step[open] {
  background: var(--raise);
  border-color: rgba(43, 232, 200, 0.4);
}

.page-about .step > summary {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  cursor: pointer;
  list-style: none;
}

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

.page-about .step > summary::before {
  content: "";
  flex: 0 0 2px;
  align-self: stretch;
  min-height: 1.35rem;
  border-radius: 2px;
  background: var(--cyan-dim);
  transition: background var(--dur) var(--ease);
}

.page-about .step[open] > summary::before {
  background: var(--orange);
}

.page-about .step > summary:focus-visible {
  outline: 2px solid var(--orange-soft);
  outline-offset: 4px;
  border-radius: 4px;
}

.page-about .step__num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.3rem;
  line-height: 1;
  color: var(--orange);
}

.page-about .step__label {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: 0.02em;
  color: var(--paper);
}

.page-about .step__body {
  margin-block-start: 0.9rem;
  padding-block-start: 0.9rem;
  border-block-start: var(--about-rule);
}

.page-about .step__body p {
  margin: 0;
  color: var(--mist);
  font-size: 0.9375rem;
  line-height: 1.8;
}

/* ---------- 03 项目与内容线 ---------- */

.page-about .svc-grid {
  display: grid;
  gap: 2.25rem;
}

.page-about .svc-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.55rem;
}

.page-about .svc-list li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.5rem 0.9rem;
  padding: 0.7rem 0.95rem;
  border-radius: var(--radius-m);
  background: var(--board);
  border: var(--about-rule);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .svc-list li:hover {
  border-color: rgba(43, 232, 200, 0.45);
  transform: translateX(3px);
}

.page-about .svc__num {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--orange);
}

.page-about .svc__name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: 0.03em;
  color: var(--paper);
}

.page-about .svc__note {
  font-size: 0.8125rem;
  color: var(--mute);
}

.page-about .lines {
  display: grid;
  gap: 0.9rem;
}

.page-about .line-card {
  padding: 1.2rem 1.3rem;
  border-radius: var(--radius-m);
  background: var(--board);
  border: var(--about-rule);
  border-inline-start: 3px solid var(--cyan);
}

.page-about .line-card:nth-child(2) {
  border-inline-start-color: var(--orange-soft);
}

.page-about .line-card:nth-child(3) {
  border-inline-start-color: var(--cyan-dim);
}

.page-about .line-card h4 {
  margin: 0 0 0.45rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: 0.02em;
  color: var(--paper);
}

.page-about .line-card p {
  margin: 0;
  color: var(--mist);
  font-size: 0.9125rem;
  line-height: 1.8;
}

/* ---------- 04 团队 ---------- */

.page-about .team-grid {
  display: grid;
  gap: 1.9rem;
}

.page-about .bars {
  display: grid;
  gap: 1.35rem;
  align-content: start;
}

.page-about .bar__head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1rem;
  margin-block-end: 0.55rem;
  font-size: 0.875rem;
  color: var(--mist);
}

.page-about .bar__val {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--cyan);
}

.page-about .bar__val--signal {
  color: var(--orange);
}

.page-about .bar__track {
  height: 10px;
  border-radius: var(--radius-pill);
  background: var(--raise);
  overflow: hidden;
}

.page-about .bar__fill {
  display: block;
  height: 100%;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--cyan-dim), var(--cyan));
  transform-origin: left center;
}

.page-about .bar__fill--signal {
  background: linear-gradient(90deg, var(--orange-soft), var(--orange));
}

.page-about .bar__fill--w100 {
  width: 100%;
}

.page-about .bar__fill--w32 {
  width: 32.4%;
}

.page-about .bar.is-revealed .bar__fill {
  animation: about-bar 720ms var(--ease) both;
}

@keyframes about-bar {
  from { transform: scaleX(0.02); }
  to { transform: scaleX(1); }
}

/* ---------- 05 合作 ---------- */

.page-about .partner-grid {
  display: grid;
  gap: 1.1rem;
}

.page-about .partner-card {
  position: relative;
  padding: 1.4rem 1.4rem 1.5rem;
  border-radius: var(--radius-l);
  background: var(--board);
  border: var(--about-rule);
  overflow: hidden;
}

.page-about .partner-card__num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(2.4rem, 6vw, 3.6rem);
  line-height: 1;
  color: var(--cyan);
  letter-spacing: -0.02em;
}

.page-about .partner-card__num--signal {
  color: var(--orange);
}

.page-about .partner-card h3 {
  margin: 0.7rem 0 0.5rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: 0.02em;
  color: var(--paper);
}

.page-about .partner-card p {
  margin: 0;
  color: var(--mist);
  font-size: 0.9125rem;
  line-height: 1.8;
}

/* ---------- 06 时间线 ---------- */

.page-about .tl-grid {
  display: grid;
  gap: 2rem;
}

.page-about .timeline {
  position: relative;
  margin: 0;
  padding: 0 0 0 2rem;
  list-style: none;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  inset-block: 0.7rem 0.7rem;
  inset-inline-start: 6px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--cyan) 0%, rgba(43, 232, 200, 0.5) 55%, rgba(43, 232, 200, 0.06) 100%);
}

.page-about .tl {
  position: relative;
  padding-block-end: 1.9rem;
}

.page-about .tl:last-child {
  padding-block-end: 0;
}

.page-about .tl::before {
  content: "";
  position: absolute;
  inset-inline-start: -2rem;
  inset-block-start: 0.3rem;
  width: 12px;
  height: 12px;
  margin-inline-start: 1px;
  border-radius: 50%;
  background: var(--orange);
  box-shadow: 0 0 0 4px var(--ink);
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .tl:hover::before,
.page-about .tl:focus-within::before {
  transform: scale(1.22);
  box-shadow: 0 0 0 4px var(--ink), 0 0 0 7px rgba(43, 232, 200, 0.35);
}

.page-about .tl__year {
  display: inline-block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  color: var(--ink);
  background: var(--orange);
  border-radius: var(--radius-pill);
  padding: 0.22rem 0.72rem;
}

.page-about .tl__title {
  margin: 0.75rem 0 0.35rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.12rem;
  letter-spacing: 0.02em;
  color: var(--paper);
}

.page-about .tl__desc {
  margin: 0;
  max-width: 46ch;
  color: var(--mist);
  font-size: 0.9125rem;
  line-height: 1.8;
}

.page-about .about-shot--tall img {
  aspect-ratio: 4 / 3;
}

/* ---------- 07 服务对象 ---------- */

.page-about .aud-grid {
  display: grid;
  gap: 1.9rem;
}

.page-about .aud-shot img {
  aspect-ratio: 3 / 4;
}

.page-about .aud-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1.15rem;
}

.page-about .aud-item {
  padding-block-start: 1.05rem;
  border-block-start: var(--about-rule);
}

.page-about .aud-item:first-child {
  padding-block-start: 0;
  border-block-start: 0;
}

.page-about .aud-item h3 {
  margin: 0 0 0.4rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: 0.02em;
  color: var(--cyan);
}

.page-about .aud-item p {
  margin: 0;
  color: var(--mist);
  font-size: 0.9125rem;
  line-height: 1.8;
}

/* ---------- 08 下一步 ---------- */

.page-about .next-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.75rem;
}

.page-about .next-list a {
  display: grid;
  gap: 0.35rem;
  padding: 1rem 1.15rem;
  border-radius: var(--radius-m);
  background: var(--board);
  border: var(--about-rule);
  text-decoration: none;
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .next-list a:hover,
.page-about .next-list a:focus-visible {
  border-color: rgba(43, 232, 200, 0.5);
  background: var(--raise);
  transform: translateX(4px);
}

.page-about .next-list__k {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: 0.03em;
  color: var(--paper);
}

.page-about .next-list__v {
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--mist);
}

/* ---------- 响应式 ---------- */

@media (min-width: 640px) {
  .page-about .about-ledger {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.5rem;
  }

  .page-about .partner-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1.25rem;
  }
}

@media (min-width: 768px) {
  .page-about .chapter__head {
    grid-template-columns: minmax(5.5rem, 1fr) 4.2fr;
    gap: 1.5rem;
  }

  .page-about .flow {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1.25rem 1.5rem;
  }

  .page-about .flow > :nth-child(even) {
    margin-block-start: 2.25rem;
  }

  .page-about .next-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0.9rem 1.1rem;
  }

  .page-about .next-list > :nth-child(even) {
    margin-block-start: 1.15rem;
  }
}

@media (min-width: 900px) {
  .page-about .origin-grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
    gap: 2.5rem;
    align-items: start;
  }

  .page-about .svc-grid {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
    gap: 2.75rem;
  }

  .page-about .team-grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    gap: 2.75rem;
    align-items: start;
  }

  .page-about .tl-grid {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
    gap: 2.75rem;
    align-items: start;
  }

  .page-about .aud-grid {
    grid-template-columns: minmax(0, 0.8fr) minmax(0, 1.2fr);
    gap: 2.75rem;
    align-items: start;
  }

  .page-about .partner-card--offset {
    margin-block-start: 2.25rem;
  }

  .page-about .about-head h1 {
    max-width: 26ch;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .bar.is-revealed .bar__fill {
    animation: none;
  }

  .page-about .next-list a,
  .page-about .svc-list li,
  .page-about .tl::before {
    transition: none;
  }
}
</<PAGE_CSS>>>