.page-about {
  --about-rule: rgba(17, 20, 24, .18);
  --about-rule-soft: rgba(17, 20, 24, .1);
  --about-text: rgba(17, 20, 24, .86);
  --about-text-soft: rgba(17, 20, 24, .74);
  --about-light: rgba(243, 237, 226, .82);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background: var(--ink);
  color: var(--paper);
  border-bottom: 3px solid var(--cyan);
  padding: clamp(1.25rem, 4vw, 2rem) 0 clamp(2.5rem, 6vw, 4.25rem);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: radial-gradient(var(--line-cyan) 1px, transparent 1px);
  background-size: 20px 20px;
  opacity: .55;
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: -20%;
  right: -10%;
  width: 58%;
  height: 140%;
  background: linear-gradient(115deg, transparent 46%, rgba(25, 227, 209, .12) 46.4%, rgba(25, 227, 209, .12) 47.2%, transparent 47.6%);
  pointer-events: none;
}

.page-about .about-hero-inner {
  position: relative;
  z-index: 1;
}

.page-about .about-hero .breadcrumbs {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .1em;
  text-transform: uppercase;
  margin-bottom: clamp(1.5rem, 4vw, 2.5rem);
}

.page-about .about-hero-grid {
  display: grid;
  gap: clamp(1.75rem, 4vw, 3rem);
}

.page-about .about-hero h1 {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.95rem, 6.4vw, 3.9rem);
  line-height: 1.06;
  letter-spacing: -.02em;
  color: var(--paper-white);
  margin: .55rem 0 0;
}

.page-about .about-hero h1 em {
  font-style: normal;
  color: var(--cyan);
}

.page-about .about-hero .eyebrow {
  color: var(--cyan-soft);
}

.page-about .about-hero-lead {
  max-width: 48ch;
  margin: 1.15rem 0 0;
  font-size: clamp(.96rem, 2.1vw, 1.08rem);
  line-height: 1.85;
  color: var(--about-light);
}

.page-about .about-hero-stamp {
  margin: 1.15rem 0 0;
  font-size: .72rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--steel);
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: .7rem;
  margin-top: 1.6rem;
}

.page-about .about-hero-figure {
  margin: 0;
  border: 3px solid rgba(25, 227, 209, .55);
  background: var(--ink-2);
  box-shadow: 10px 10px 0 rgba(25, 227, 209, .16);
}

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

/* ---------- 阅读画布 ---------- */
.page-about .about-body {
  background: var(--paper);
  color: var(--graphite);
  padding: clamp(2rem, 5vw, 3.5rem) 0 clamp(3rem, 7vw, 5rem);
}

.page-about .about-layout {
  display: grid;
  gap: clamp(1.5rem, 4vw, 2.5rem);
}

/* ---------- 章节索引 ---------- */
.page-about .about-index {
  border-top: 3px solid var(--graphite);
  padding-top: .85rem;
}

.page-about .about-index-title {
  margin: 0 0 .75rem;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--teal-deep);
}

.page-about .about-index-list {
  list-style: none;
  margin: 0;
  padding: 0 0 .4rem;
  display: flex;
  gap: .5rem;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-index-list li {
  flex: 0 0 auto;
}

.page-about .about-index-list a {
  display: inline-flex;
  align-items: baseline;
  gap: .45rem;
  padding: .45rem .7rem;
  border: 2px solid var(--about-rule);
  font-size: .82rem;
  line-height: 1.4;
  color: var(--graphite);
  text-decoration: none;
  white-space: nowrap;
  transition: border-color .18s ease, color .18s ease;
}

.page-about .about-index-list a .num {
  font-size: .68rem;
  color: var(--teal-deep);
}

.page-about .about-index-list a:hover,
.page-about .about-index-list a:focus-visible {
  border-color: var(--flame);
  color: var(--flame);
}

/* ---------- 内容块 ---------- */
.page-about .about-block {
  padding-top: clamp(1.5rem, 3vw, 2.25rem);
  border-top: 1px solid var(--about-rule);
  margin-bottom: clamp(2.25rem, 5vw, 3.75rem);
}

.page-about .about-content > .about-block:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .about-block-head {
  display: flex;
  align-items: baseline;
  gap: .7rem;
  margin-bottom: 1rem;
}

.page-about .about-block-num {
  font-size: .78rem;
  letter-spacing: .1em;
  color: var(--flame);
}

.page-about .about-block h2 {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(1.3rem, 3.4vw, 1.95rem);
  line-height: 1.28;
  letter-spacing: -.01em;
  color: var(--graphite);
}

.page-about .about-block-lead {
  margin: 1.1rem 0 0;
  font-size: .95rem;
  line-height: 1.8;
  color: var(--about-text-soft);
}

.page-about .about-prose {
  font-size: clamp(.94rem, 2.1vw, 1.01rem);
  line-height: 1.85;
  color: var(--about-text);
}

.page-about .about-prose p {
  margin: 0 0 1rem;
}

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

.page-about .about-prose strong {
  color: var(--graphite);
  font-weight: 700;
}

/* ---------- 主张引块 ---------- */
.page-about .about-quote {
  margin: clamp(1.5rem, 4vw, 2.25rem) 0 0;
  padding: clamp(1.1rem, 3vw, 1.7rem);
  background: var(--paper-white);
  border: 3px solid var(--graphite);
  box-shadow: 8px 8px 0 rgba(14, 111, 106, .3);
}

.page-about .about-quote p {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(1.35rem, 4.2vw, 2.05rem);
  line-height: 1.2;
  letter-spacing: -.01em;
  color: var(--graphite);
}

.page-about .about-quote footer {
  margin-top: .6rem;
  font-family: var(--font-mono);
  font-size: .68rem;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--teal-deep);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: 1.5rem 0 0;
  padding: 0;
  position: relative;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: .5rem;
  bottom: .6rem;
  width: 4px;
  background: var(--teal-deep);
}

.page-about .tl-item {
  position: relative;
  padding-left: 2.25rem;
  margin-bottom: 1rem;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: .55rem;
  width: 18px;
  height: 18px;
  background: var(--paper-white);
  border: 4px solid var(--teal-deep);
}

.page-about .tl-details summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: .55rem .8rem;
  cursor: pointer;
  padding: .15rem 0;
  list-style: none;
}

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

.page-about .tl-details summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: .95rem;
  color: var(--flame);
  margin-left: auto;
}

.page-about .tl-details[open] summary::after {
  content: "–";
}

.page-about .tl-year {
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--graphite);
}

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

.page-about .tl-note {
  padding: .55rem 0 .2rem;
  border-top: 2px solid var(--about-rule-soft);
  margin-top: .5rem;
}

.page-about .tl-note p {
  margin: 0;
  font-size: .92rem;
  line-height: 1.8;
  color: var(--about-text-soft);
}

/* ---------- 团队 ---------- */
.page-about .about-split {
  display: grid;
  gap: clamp(1.25rem, 3vw, 2rem);
  margin-top: 1.1rem;
}

.page-about .about-figure {
  margin: 0;
  border: 3px solid var(--graphite);
  background: var(--ink-2);
}

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

.page-about .about-figure figcaption {
  padding: .6rem .75rem;
  background: var(--graphite);
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: .68rem;
  line-height: 1.6;
  letter-spacing: .04em;
}

.page-about .about-figure-wide {
  margin-top: clamp(1.5rem, 3vw, 2rem);
}

.page-about .about-steps {
  list-style: none;
  margin: 1.25rem 0 0;
  padding: 0;
  display: grid;
  gap: .8rem;
}

.page-about .about-steps li {
  display: grid;
  grid-template-columns: 2rem minmax(0, 1fr);
  gap: .75rem;
  padding-top: .7rem;
  border-top: 2px solid var(--about-rule-soft);
  font-size: .94rem;
  line-height: 1.75;
  color: var(--about-text);
}

.page-about .step-k {
  font-size: .74rem;
  letter-spacing: .1em;
  color: var(--flame);
  padding-top: .28rem;
}

/* ---------- 服务人群 ---------- */
.page-about .about-users {
  list-style: none;
  margin: 1.2rem 0 0;
  padding: 0;
  display: grid;
  gap: 1.1rem;
}

.page-about .about-user {
  border-top: 3px solid var(--teal-deep);
  padding-top: .8rem;
}

.page-about .about-user-num {
  display: block;
  font-size: .7rem;
  letter-spacing: .12em;
  color: var(--teal-deep);
  margin-bottom: .35rem;
}

.page-about .about-user h3 {
  margin: 0 0 .4rem;
  font-family: var(--font-head);
  font-size: 1rem;
  font-weight: 800;
  line-height: 1.35;
  color: var(--graphite);
}

.page-about .about-user p {
  margin: 0;
  font-size: .9rem;
  line-height: 1.75;
  color: var(--about-text-soft);
}

/* ---------- 规模数据 ---------- */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: clamp(1.5rem, 3vw, 2rem);
  background: var(--about-rule);
  border: 3px solid var(--graphite);
}

.page-about .about-stat {
  background: var(--paper-white);
  padding: .85rem .8rem;
}

.page-about .about-stat-num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.25rem, 3.6vw, 1.7rem);
  line-height: 1.1;
  letter-spacing: -.01em;
  color: var(--flame);
  font-variant-numeric: tabular-nums;
}

.page-about .about-stat-label {
  display: block;
  margin-top: .35rem;
  font-size: .76rem;
  line-height: 1.5;
  color: var(--about-text-soft);
}

/* ---------- 合作区块 ---------- */
.page-about .about-partners {
  background: var(--ink-2);
  color: var(--paper);
  border-top: 3px solid var(--cyan);
  padding: clamp(2.25rem, 5vw, 4rem) 0 clamp(2.5rem, 5vw, 3.5rem);
}

.page-about .about-block-head-dark h2 {
  color: var(--paper-white);
}

.page-about .about-prose-dark {
  color: var(--about-light);
  max-width: 62ch;
}

.page-about .about-prose-dark strong {
  color: var(--paper-white);
}

.page-about .about-partner-grid {
  display: grid;
  gap: 1rem;
  margin-top: clamp(1.5rem, 3vw, 2rem);
}

.page-about .about-partner {
  border-left: 3px solid var(--cyan);
  padding-left: .9rem;
}

.page-about .about-partner strong {
  display: block;
  margin-bottom: .35rem;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .14em;
  text-transform: uppercase;
  font-weight: 500;
  color: var(--cyan-soft);
}

.page-about .about-partner p {
  margin: 0;
  font-size: .9rem;
  line-height: 1.75;
  color: var(--about-light);
}

.page-about .about-partners-note {
  margin-top: clamp(1.25rem, 3vw, 1.75rem);
  padding-left: .9rem;
  border-left: 3px solid var(--flame);
}

.page-about .about-cta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-top: clamp(1.75rem, 4vw, 2.75rem);
  padding-top: 1.25rem;
  border-top: 3px solid var(--cyan);
}

.page-about .about-cta p {
  margin: 0;
  max-width: 26ch;
  font-family: var(--font-head);
  font-size: clamp(1.05rem, 3vw, 1.4rem);
  font-weight: 800;
  line-height: 1.35;
  color: var(--paper-white);
}

.page-about .about-cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: .6rem;
}

/* ---------- 响应式 ---------- */
@media (min-width: 760px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, .88fr);
    align-items: start;
  }

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

  .page-about .about-partner-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: clamp(1rem, 2.5vw, 1.75rem);
  }
}

@media (min-width: 820px) {
  .page-about .about-users {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: clamp(1rem, 2.5vw, 1.75rem);
  }
}

@media (min-width: 920px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, .92fr);
    align-items: end;
  }

  .page-about .about-hero-figure {
    margin-bottom: 1.5rem;
  }
}

@media (min-width: 1000px) {
  .page-about .about-layout {
    grid-template-columns: 232px minmax(0, 1fr);
    gap: clamp(2rem, 4vw, 4rem);
    align-items: start;
  }

  .page-about .about-index {
    position: sticky;
    top: calc(var(--header-h) + 1.5rem);
    align-self: start;
  }

  .page-about .about-index-list {
    display: block;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-index-list li {
    flex: none;
    border-bottom: 1px solid var(--about-rule);
  }

  .page-about .about-index-list a {
    display: flex;
    border: 0;
    padding: .65rem 0;
    white-space: normal;
    font-size: .86rem;
  }

  .page-about .about-index-list a:hover,
  .page-about .about-index-list a:focus-visible {
    color: var(--flame);
  }
}
<<<END>>>