.page-about {
  --about-line: rgba(147, 168, 157, 0.24);
  --about-line-soft: rgba(147, 168, 157, 0.12);
  position: relative;
  background-color: var(--ink-green);
  color: var(--cream);
  font-family: var(--font-body);
  overflow-x: clip;
}

.page-about::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, var(--about-line-soft) 1px, transparent 1px),
    linear-gradient(to bottom, var(--about-line-soft) 1px, transparent 1px);
  background-size: 72px 72px;
  opacity: 0.55;
}

.page-about > .content-shell {
  position: relative;
  z-index: 1;
}

/* 面包屑 */
.page-about .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 20px 0 0;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--sage);
}

.page-about .breadcrumb__item {
  color: var(--sage);
  text-decoration: none;
}

.page-about .breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  margin-right: 8px;
  color: var(--track);
}

.page-about .breadcrumb__item[aria-current] {
  color: var(--sand);
}

/* 首屏 */
.page-about .about-hero {
  display: grid;
  gap: 28px;
  padding: 28px 0 44px;
  border-bottom: 1px solid var(--about-line);
}

.page-about .about-hero__title {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(2.35rem, 8vw, 4.6rem);
  line-height: 0.98;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .about-hero__title em {
  font-style: normal;
  color: var(--sand);
}

.page-about .about-hero__lede {
  margin: 18px 0 0;
  max-width: 38em;
  font-size: 1rem;
  line-height: 1.75;
  color: rgba(244, 236, 221, 0.82);
}

.page-about .about-hero__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 22px;
}

.page-about .about-hero__tags .tag {
  padding: 6px 10px;
  border: 1px solid var(--about-line);
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--sand);
}

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

.page-about .figure__img {
  border: 1px solid var(--about-line);
  overflow: hidden;
}

.page-about .figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  filter: saturate(0.55) contrast(1.06) brightness(0.94);
}

.page-about .figure__caption {
  margin-top: 10px;
  font-size: 0.76rem;
  letter-spacing: 0.04em;
  color: var(--sage);
}

/* 主分栏 */
.page-about .about-split {
  display: grid;
  gap: 36px;
  padding-top: 44px;
}

.page-about .about-aside__label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.2em;
  color: var(--sand);
}

.page-about .about-aside__note {
  margin: 10px 0 16px;
  font-size: 0.82rem;
  line-height: 1.65;
  color: var(--sage);
}

.page-about .about-scale {
  list-style: none;
  margin: 0;
  padding: 0 0 0 14px;
  border-left: 1px solid var(--about-line);
  display: grid;
  gap: 2px;
}

.page-about .about-scale__item {
  position: relative;
  display: flex;
  gap: 10px;
  align-items: baseline;
  padding: 7px 0;
}

.page-about .about-scale__item::before {
  content: "";
  position: absolute;
  left: -18px;
  top: 15px;
  width: 7px;
  height: 7px;
  background: var(--track);
  transform: rotate(45deg);
}

.page-about .about-scale__ver {
  flex: none;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  color: var(--sand);
}

.page-about .about-scale__name {
  font-size: 0.8rem;
  line-height: 1.45;
  color: rgba(244, 236, 221, 0.72);
}

.page-about .about-subscribe {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  margin-top: 22px;
  width: 100%;
}

/* 章节 */
.page-about .about-section {
  padding: 36px 0;
  border-bottom: 1px solid var(--about-line-soft);
}

.page-about .about-section:first-child {
  padding-top: 0;
}

.page-about .section-head {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 24px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--about-line);
}

.page-about .section-head__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(1.45rem, 4.4vw, 2.2rem);
  line-height: 1.1;
  color: var(--paper);
}

.page-about .section-head__note {
  margin: 0;
  max-width: 32em;
  font-size: 0.82rem;
  line-height: 1.6;
  color: var(--sage);
}

/* 四类档案 */
.page-about .about-modules {
  display: grid;
  gap: 1px;
  background: var(--about-line);
  border: 1px solid var(--about-line);
}

.page-about .about-module {
  background: var(--ink-green);
  padding: 20px 18px 22px;
}

.page-about .about-module__no {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.18em;
  color: var(--sand);
}

.page-about .about-module h3 {
  margin: 10px 0 8px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.28rem;
  color: var(--paper);
}

.page-about .about-module p {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.75;
  color: rgba(244, 236, 221, 0.76);
}

.page-about .about-figure {
  margin: 26px 0 0;
}

.page-about .about-figure--tight {
  margin-top: 0;
}

/* 流程折叠 */
.page-about .about-fold {
  margin-bottom: 8px;
  border: 1px solid var(--about-line);
  background: rgba(18, 54, 43, 0.6);
}

.page-about .about-fold__summary {
  display: flex;
  gap: 12px;
  align-items: baseline;
  min-height: 44px;
  padding: 14px 16px;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
  font-size: 1.06rem;
  color: var(--paper);
}

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

.page-about .about-fold__summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  color: var(--lime);
}

.page-about .about-fold[open] .about-fold__summary::after {
  content: "–";
}

.page-about .about-fold__summary:focus-visible {
  outline: 2px solid var(--lime);
  outline-offset: -3px;
}

.page-about .about-fold__step {
  flex: none;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  color: var(--sand);
}

.page-about .about-fold__body {
  padding: 0 16px 18px;
  font-size: 0.9rem;
  line-height: 1.78;
  color: rgba(244, 236, 221, 0.78);
}

.page-about .about-fold__body p {
  margin: 0;
}

/* 规模数字 */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--about-line);
  border: 1px solid var(--about-line);
}

.page-about .about-stat {
  background: var(--field-green);
  padding: 18px 14px 20px;
}

.page-about .about-stat__value {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.7rem, 6vw, 2.6rem);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--sand);
}

.page-about .about-stat__label {
  display: block;
  margin-top: 10px;
  font-size: 0.76rem;
  letter-spacing: 0.06em;
  color: var(--sage);
}

.page-about .about-stats__foot {
  margin: 18px 0 0;
  font-size: 0.86rem;
  line-height: 1.75;
  color: rgba(244, 236, 221, 0.74);
}

/* 版本演进 */
.page-about .about-versions {
  display: grid;
  gap: 26px;
}

.page-about .about-phases {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .about-phase {
  padding-left: 16px;
  border-left: 2px solid var(--track);
}

.page-about .about-phase strong {
  display: block;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.1rem;
  letter-spacing: 0.02em;
  color: var(--paper);
}

.page-about .about-phase span {
  display: block;
  margin-top: 6px;
  font-size: 0.86rem;
  line-height: 1.72;
  color: rgba(244, 236, 221, 0.74);
}

/* 合作纸面 */
.page-about .about-partners {
  background: var(--cream);
  color: var(--charcoal);
  padding: 26px 20px 28px;
  clip-path: polygon(0 0, calc(100% - 26px) 0, 100% 26px, 100% 100%, 26px 100%, 0 calc(100% - 26px));
}

.page-about .about-partners__title {
  margin: 0 0 18px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.4rem, 4.6vw, 2rem);
  line-height: 1.08;
  color: var(--charcoal);
}

.page-about .about-partners__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .about-partners__item {
  padding-top: 14px;
  border-top: 1px solid rgba(46, 90, 76, 0.28);
}

.page-about .about-partners__item strong {
  display: block;
  margin-bottom: 6px;
  font-size: 0.98rem;
  color: var(--charcoal);
}

.page-about .about-partners__item p {
  margin: 0;
  font-size: 0.86rem;
  line-height: 1.72;
  color: #33403a;
}

.page-about .about-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

.page-about .about-actions .btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
}

/* 收尾订阅带 */
.page-about .about-cta {
  display: grid;
  gap: 18px;
  margin: 40px 0 56px;
  padding: 24px 20px;
  border: 1px solid rgba(200, 255, 77, 0.5);
  background: rgba(200, 255, 77, 0.07);
}

.page-about .about-cta strong {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.22rem;
  line-height: 1.2;
  color: var(--paper);
}

.page-about .about-cta p {
  margin: 0;
  font-size: 0.86rem;
  line-height: 1.75;
  color: rgba(244, 236, 221, 0.82);
}

.page-about .about-cta .btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  justify-self: start;
}

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

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

  .page-about .about-partners {
    padding: 32px 30px 34px;
  }

  .page-about .about-partners__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
  }

  .page-about .about-versions {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 32px;
    align-items: start;
  }

  .page-about .about-cta {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    padding: 28px 30px;
  }

  .page-about .about-cta .btn {
    justify-self: end;
  }
}

/* 桌面 */
@media (min-width: 1000px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: end;
    gap: 52px;
    padding: 40px 0 60px;
  }

  .page-about .about-hero__lede {
    font-size: 1.05rem;
  }

  .page-about .about-split {
    grid-template-columns: 236px minmax(0, 1fr);
    gap: 56px;
    padding-top: 68px;
    align-items: start;
  }

  .page-about .about-aside__sticky {
    position: sticky;
    top: calc(var(--header-h) + 24px);
  }

  .page-about .about-section {
    padding: 48px 0;
  }

  .page-about .about-module {
    padding: 24px 22px 26px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-fold__summary::after {
    transition: none;
  }
}
<<<PAGE_CSS_END>>>