.page-about {
  --about-line: rgba(159, 179, 200, 0.16);
  --about-line-soft: rgba(159, 179, 200, 0.08);
  background:
    radial-gradient(circle at 84% 4%, rgba(57, 230, 214, 0.07), transparent 46%),
    radial-gradient(circle at 6% 22%, rgba(232, 174, 71, 0.06), transparent 40%),
    var(--ink);
  color: var(--paper);
  overflow-x: clip;
}

.page-about .breadcrumb {
  padding-top: 1.4rem;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: 1rem;
  padding: 1.6rem 0 2.2rem;
  border-bottom: 1px solid var(--about-line);
}

.page-about .about-hero .eyebrow {
  letter-spacing: 0.18em;
  color: var(--cyan);
  font-size: 0.72rem;
}

.page-about .about-hero__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  line-height: 1.04;
  letter-spacing: -0.015em;
  font-size: clamp(2.1rem, 7.6vw, 4.6rem);
  color: var(--paper);
  text-wrap: balance;
}

.page-about .about-hero__title em {
  font-style: normal;
  color: var(--amber);
  display: inline-block;
}

.page-about .about-hero__lead {
  margin: 0;
  max-width: 62ch;
  color: var(--mist);
}

.page-about .about-hero__stats {
  list-style: none;
  margin: 0.8rem 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--about-line);
  border: 1px solid var(--about-line);
  border-radius: var(--radius-m);
  overflow: hidden;
}

.page-about .about-hero__stats li {
  background: linear-gradient(160deg, var(--ink-2), var(--ink-3));
  padding: 0.95rem 1rem;
  display: grid;
  gap: 0.28rem;
}

.page-about .stat-num {
  font-size: clamp(1.5rem, 5.4vw, 2.15rem);
  line-height: 1;
  color: var(--amber);
  font-weight: 600;
  letter-spacing: -0.01em;
}

.page-about .stat-label {
  font-size: 0.8rem;
  line-height: 1.45;
  color: var(--mist);
}

/* ---------- 章节索引 ---------- */
.page-about .about-index {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  padding: 1.2rem 0 0.4rem;
}

.page-about .about-index .chapter-link {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.06em;
  padding: 0.42rem 0.74rem;
  border-radius: 999px;
  border: 1px solid var(--about-line);
  color: var(--mist);
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.22s var(--ease), background 0.22s var(--ease), border-color 0.22s var(--ease);
}

.page-about .about-index .chapter-link:hover,
.page-about .about-index .chapter-link:focus-visible,
.page-about .about-index .chapter-link.is-active {
  color: var(--ink);
  background: var(--amber);
  border-color: var(--amber);
}

/* ---------- 通用块 ---------- */
.page-about .about-block {
  padding: 2.6rem 0 0.6rem;
  scroll-margin-top: 1.5rem;
}

.page-about .section-head__title {
  font-family: var(--font-display);
  font-size: clamp(1.55rem, 4.6vw, 2.5rem);
  line-height: 1.14;
  letter-spacing: -0.01em;
  margin: 0.35rem 0 0.55rem;
  color: var(--paper);
}

.page-about .section-head__note {
  margin: 0;
  max-width: 58ch;
  color: var(--mist);
  font-size: 0.94rem;
  line-height: 1.7;
}

.page-about .section-head .chapter-num {
  color: var(--cyan);
  letter-spacing: 0.16em;
  font-size: 0.74rem;
}

.page-about .about-visual {
  margin: 0;
}

.page-about .about-visual img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: var(--radius-l);
  border: 1px solid var(--about-line);
  background: var(--ink-2);
}

.page-about .about-visual--banner {
  margin: 1.6rem 0 0.4rem;
}

.page-about .about-visual--banner img {
  aspect-ratio: 7 / 3;
}

.page-about .about-visual--grid img {
  aspect-ratio: 10 / 7;
}

.page-about .about-visual--desk {
  margin-top: 1.4rem;
}

.page-about .about-visual--desk img {
  aspect-ratio: 3 / 2;
}

/* ---------- 时间线 ---------- */
.page-about .timeline {
  list-style: none;
  margin: 1.8rem 0 0;
  padding: 0;
  display: grid;
  gap: 1.5rem;
}

.page-about .timeline__item {
  position: relative;
  display: grid;
  gap: 0.42rem;
  padding-left: 1.6rem;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.6rem;
  bottom: -1.5rem;
  width: 1px;
  background: linear-gradient(to bottom, var(--line-strong), var(--about-line-soft));
}

.page-about .timeline__item:last-child::before {
  background: linear-gradient(to bottom, var(--line-strong), transparent);
  bottom: 0;
}

.page-about .timeline__item::after {
  content: "";
  position: absolute;
  left: -4px;
  top: 0.62rem;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--amber);
  box-shadow: 0 0 0 4px rgba(232, 174, 71, 0.12);
}

.page-about .timeline__year {
  font-size: clamp(1.7rem, 6vw, 2.3rem);
  line-height: 1;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--amber);
}

.page-about .timeline__title {
  margin: 0 0 0.4rem;
  font-family: var(--font-display);
  font-size: clamp(1.05rem, 3.4vw, 1.32rem);
  line-height: 1.35;
  color: var(--paper);
}

.page-about .timeline__body p {
  margin: 0;
  color: var(--mist);
  font-size: 0.94rem;
  line-height: 1.75;
}

/* ---------- 服务版图 ---------- */
.page-about .about-coverage {
  display: grid;
  gap: 1.8rem;
  margin-top: 1.7rem;
}

.page-about .about-coverage__text p {
  margin: 0 0 1rem;
  color: var(--mist);
  font-size: 0.95rem;
  line-height: 1.78;
}

.page-about .coverage__list {
  list-style: none;
  margin: 1.2rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.7rem;
}

.page-about .coverage__list li {
  display: grid;
  grid-template-columns: 10px 1fr;
  gap: 0.75rem;
  align-items: start;
  padding: 0.85rem 0.95rem;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-m);
  background: linear-gradient(150deg, rgba(16, 36, 59, 0.92), rgba(8, 20, 38, 0.55));
}

.page-about .coverage__dot {
  width: 7px;
  height: 7px;
  margin-top: 0.5rem;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 3px rgba(57, 230, 214, 0.14);
}

.page-about .coverage__list strong {
  display: block;
  font-size: 0.92rem;
  color: var(--paper);
  margin-bottom: 0.22rem;
  letter-spacing: 0.01em;
}

.page-about .coverage__list p {
  margin: 0;
  font-size: 0.86rem;
  line-height: 1.65;
  color: var(--mist);
}

/* ---------- 暖纸面板 ---------- */
.page-about .about-paper {
  position: relative;
  margin-top: 1.6rem;
  padding: 1.7rem 1.25rem 1.5rem;
  border-radius: var(--radius-l);
  background: var(--paper);
  color: var(--ink);
  overflow: hidden;
  box-shadow: 0 30px 70px -38px rgba(0, 0, 0, 0.85);
}

.page-about .about-paper::after {
  content: "";
  position: absolute;
  right: -90px;
  bottom: -130px;
  width: 280px;
  height: 280px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(232, 174, 71, 0.42), transparent 68%);
  pointer-events: none;
}

.page-about .about-paper > * {
  position: relative;
  z-index: 1;
}

.page-about .about-paper__kicker {
  margin: 0;
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  color: var(--teal);
}

.page-about .about-paper h3 {
  margin: 0.5rem 0 0.7rem;
  font-family: var(--font-display);
  font-size: clamp(1.22rem, 4vw, 1.72rem);
  line-height: 1.28;
  letter-spacing: -0.008em;
  color: var(--ink);
}

.page-about .about-paper p {
  margin: 0 0 0.9rem;
  color: rgba(8, 20, 38, 0.76);
  font-size: 0.93rem;
  line-height: 1.75;
}

.page-about .about-paper__grid {
  display: grid;
  gap: 1.1rem;
  margin-top: 1.2rem;
  padding-top: 1.1rem;
  border-top: 1px solid rgba(8, 20, 38, 0.14);
}

.page-about .about-paper h4 {
  margin: 0 0 0.4rem;
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--teal);
}

.page-about .paper-details {
  margin-top: 1.2rem;
  padding-top: 1rem;
  border-top: 1px solid rgba(8, 20, 38, 0.14);
}

.page-about .paper-details summary {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  cursor: pointer;
  list-style: none;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--ink);
}

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

.page-about .paper-details summary::before {
  content: "+";
  font-family: var(--font-mono);
  font-size: 1.1rem;
  line-height: 1;
  color: var(--teal);
  transition: transform 0.22s var(--ease);
}

.page-about .paper-details[open] summary::before {
  transform: rotate(45deg);
}

.page-about .paper-details p {
  margin: 0.8rem 0 0;
}

/* ---------- 品质方法 ---------- */
.page-about .flow {
  list-style: none;
  margin: 1.8rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.9rem;
}

.page-about .flow__item {
  position: relative;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.95rem;
  align-items: start;
  padding: 1.05rem 1rem;
  border-radius: var(--radius-m);
  border: 1px solid var(--about-line);
  background: linear-gradient(155deg, rgba(16, 36, 59, 0.94), rgba(8, 20, 38, 0.7));
}

.page-about .flow__item:not(:last-child)::after {
  content: "";
  position: absolute;
  left: calc(1rem + 1.2rem);
  top: 100%;
  width: 1px;
  height: 0.9rem;
  background: var(--line-strong);
}

.page-about .flow__num {
  display: grid;
  place-items: center;
  width: 2.4rem;
  height: 2.4rem;
  border-radius: 50%;
  font-size: 0.82rem;
  color: var(--amber);
  background: rgba(232, 174, 71, 0.1);
  border: 1px solid var(--line-strong);
  flex: 0 0 auto;
}

.page-about .flow__text h3 {
  margin: 0 0 0.35rem;
  font-family: var(--font-display);
  font-size: 1.02rem;
  letter-spacing: 0.01em;
  color: var(--paper);
}

.page-about .flow__text p {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 里程碑 ---------- */
.page-about .miles {
  display: grid;
  gap: 0.9rem;
  margin-top: 1.7rem;
}

.page-about .mile {
  display: grid;
  gap: 0.45rem;
  align-content: start;
  padding: 1.15rem 1.05rem;
  border-radius: var(--radius-m);
  border: 1px solid var(--about-line);
  background: var(--ink-2);
}

.page-about .mile__tag {
  justify-self: start;
  padding: 0.14rem 0.58rem;
  border-radius: 999px;
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  color: var(--ink);
  background: var(--amber);
}

.page-about .mile h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 1.02rem;
  line-height: 1.36;
  color: var(--paper);
}

.page-about .mile p {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .miles__note {
  margin: 1.3rem 0 0;
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .miles__note a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(57, 230, 214, 0.35);
}

.page-about .miles__note a:hover,
.page-about .miles__note a:focus-visible {
  color: var(--amber-soft);
  border-bottom-color: var(--amber-soft);
}

/* ---------- 结尾路径 ---------- */
.page-about .about-cta {
  margin-top: 2.8rem;
  padding: 1.6rem 1.2rem;
  border-radius: var(--radius-l);
  border: 1px solid var(--line-strong);
  background:
    radial-gradient(circle at 88% 12%, rgba(232, 174, 71, 0.14), transparent 55%),
    linear-gradient(160deg, var(--ink-2), var(--ink-3));
}

.page-about .about-cta__lead {
  margin: 0 0 1.1rem;
  font-size: 0.95rem;
  line-height: 1.75;
  color: var(--paper);
  max-width: 54ch;
}

.page-about .about-cta__row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
}

.page-about .about-cta__hint {
  margin: 1rem 0 0;
  font-size: 0.84rem;
  color: var(--mist);
}

.page-about .about-cta__hint a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(57, 230, 214, 0.35);
}

.page-about .about-cta__hint a:hover,
.page-about .about-cta__hint a:focus-visible {
  color: var(--amber-soft);
  border-bottom-color: var(--amber-soft);
}

.page-about a:focus-visible,
.page-about summary:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

/* ---------- 平板 ---------- */
@media (min-width: 760px) {
  .page-about .about-hero {
    padding: 2.2rem 0 2.8rem;
  }

  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    margin-top: 1.2rem;
  }

  .page-about .about-paper__grid {
    grid-template-columns: 1fr 1fr;
    gap: 1.8rem;
  }

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

  .page-about .about-cta {
    padding: 2rem 1.8rem;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .page-about .about-block {
    padding-top: 3.4rem;
  }

  .page-about .timeline__item {
    grid-template-columns: minmax(120px, 170px) 1fr;
    column-gap: 2.2rem;
    padding-left: 2.4rem;
    align-items: start;
  }

  .page-about .timeline__year {
    font-size: 2.7rem;
  }

  .page-about .about-coverage {
    grid-template-columns: 1.05fr 0.95fr;
    gap: 2.6rem;
    align-items: center;
  }

  .page-about .about-paper {
    padding: 2.2rem 2rem 1.9rem;
  }

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

  .page-about .flow__item:not(:last-child)::after {
    display: none;
  }

  .page-about .flow__item:last-child {
    grid-column: 1 / -1;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index .chapter-link,
  .page-about .paper-details summary::before {
    transition: none;
  }
}

@media print {
  .page-about {
    background: #fff;
    color: #111;
  }

  .page-about .about-index,
  .page-about .about-cta,
  .page-about .about-visual {
    display: none;
  }

  .page-about .timeline__item,
  .page-about .flow__item,
  .page-about .mile {
    border-color: #bbb;
    background: #fff;
    break-inside: avoid;
  }

  .page-about .timeline__year,
  .page-about .stat-num {
    color: #8a5b00;
  }

  .page-about .timeline__body p,
  .page-about .flow__text p,
  .page-about .mile p,
  .page-about .coverage__list p {
    color: #333;
  }

  .page-about .about-paper {
    background: #fff;
    box-shadow: none;
    border: 1px solid #bbb;
  }
}
<<<END>>>