.page-about {
  --about-gap: clamp(20px, 4vw, 44px);
  --about-edge: 2px solid var(--ink-900);
  background: var(--cream);
  color: var(--graphite);
  overflow-x: clip;
}

/* ---------- 开篇分屏 ---------- */
.page-about .about-open {
  display: grid;
  grid-template-columns: 1fr;
  border-bottom: var(--about-edge);
}

.page-about .about-open__visual {
  position: relative;
  min-height: 300px;
  background: var(--ink-900);
  overflow: hidden;
}

.page-about .about-open__visual img {
  display: block;
  width: 100%;
  height: 100%;
  min-height: 300px;
  object-fit: cover;
  opacity: 0.6;
}

.page-about .about-open__visual::before {
  content: "";
  position: absolute;
  left: -12%;
  bottom: 24%;
  width: 130%;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--copper-light) 40%, var(--copper) 60%, transparent);
  transform: rotate(-18deg);
  z-index: 2;
}

.page-about .about-open__visual::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 4px;
  background: var(--copper);
  z-index: 2;
}

.page-about .about-open__no {
  position: absolute;
  top: 18px;
  left: 20px;
  z-index: 3;
  color: var(--copper-light);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.18em;
}

.page-about .about-open__caption {
  position: absolute;
  left: 20px;
  bottom: 22px;
  z-index: 3;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--sand);
}

.page-about .about-open__text {
  padding: clamp(28px, 5vw, 60px) var(--gutter);
  background: var(--cream);
}

.page-about .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0 0 22px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ink-500);
}

.page-about .breadcrumb a {
  color: var(--ink-500);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--t), color var(--t);
}

.page-about .breadcrumb a:hover,
.page-about .breadcrumb a:focus-visible {
  color: var(--ink-900);
  border-bottom-color: var(--copper);
}

.page-about .about-open h1 {
  margin: 12px 0 20px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(27px, 5vw, 48px);
  line-height: 1.16;
  letter-spacing: -0.02em;
  color: var(--ink-900);
  max-width: 20em;
}

.page-about .about-open__lede {
  margin: 0 0 30px;
  max-width: 34em;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.85;
}

.page-about .about-facts {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 2px solid var(--ink-900);
  max-width: 34em;
}

.page-about .about-facts li {
  display: grid;
  grid-template-columns: 5.6em 1fr;
  gap: 14px;
  padding: 11px 0;
  border-bottom: 1px solid var(--sand);
  font-size: 14px;
  line-height: 1.6;
}

.page-about .about-facts__k {
  font-family: var(--font-head);
  font-weight: 700;
  color: var(--ink-500);
}

.page-about .about-facts__v {
  font-family: var(--font-body);
  color: var(--graphite);
}

/* ---------- 通用章节 ---------- */
.page-about .about-chapter {
  padding: clamp(44px, 7vw, 82px) 0;
  border-top: 1px solid var(--sand);
}

.page-about .about-chapter--sand {
  background: var(--sand);
  border-top: 2px solid var(--ink-900);
}

.page-about .about-chapter--ink {
  background: var(--ink-900);
  border-top: 2px solid var(--ink-900);
  color: var(--cream);
}

.page-about .about-chapter__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 18px;
  margin-bottom: clamp(22px, 3.4vw, 38px);
}

.page-about .about-chapter__head .index-num {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.18em;
  color: var(--copper);
}

.page-about .about-chapter h2 {
  display: flex;
  align-items: center;
  gap: 14px;
  margin: 0;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(22px, 3.1vw, 32px);
  line-height: 1.24;
  letter-spacing: -0.01em;
  color: var(--ink-900);
}

.page-about .about-chapter h2::before {
  content: "";
  flex: 0 0 auto;
  width: 30px;
  height: 3px;
  background: var(--copper);
}

.page-about .about-chapter--ink h2 {
  color: var(--cream);
}

.page-about .about-chapter--ink .about-chapter__head .index-num {
  color: var(--copper-light);
}

.page-about .about-chapter__body p {
  max-width: 38em;
  margin: 0 0 1.2em;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.85;
}

.page-about .about-chapter__body--dark p {
  color: var(--sand);
}

.page-about .chapter-link {
  margin-top: 1.6em;
  font-family: var(--font-head);
  font-size: 15px;
  font-weight: 700;
}

.page-about .chapter-link a {
  color: var(--ink-900);
  text-decoration: none;
  border-bottom: 2px solid var(--copper);
  padding-bottom: 2px;
  transition: color var(--t), border-color var(--t);
}

.page-about .chapter-link a:hover,
.page-about .chapter-link a:focus-visible {
  color: var(--cinnabar);
  border-bottom-color: var(--cinnabar);
}

/* ---------- 问题清单 ---------- */
.page-about .problem-list {
  list-style: none;
  margin: 1.6em 0;
  padding: 0;
  display: grid;
  gap: 2px;
  background: var(--ink-900);
  border: var(--about-edge);
  max-width: 44em;
}

.page-about .problem-list li {
  background: var(--cream);
  padding: 14px 18px 15px;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.75;
}

.page-about .problem-list strong {
  display: inline-block;
  min-width: 4.4em;
  margin-right: 10px;
  font-family: var(--font-head);
  font-weight: 900;
  color: var(--ink-900);
  letter-spacing: -0.01em;
}

/* ---------- 原则方框阵 ---------- */
.page-about .principles-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}

.page-about .principles {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2px;
  background: var(--ink-900);
  border: var(--about-edge);
  box-shadow: var(--shadow-hard);
}

.page-about .principle {
  position: relative;
  padding: 24px 20px 26px;
  background: var(--cream);
  transition: background var(--t), box-shadow var(--t);
}

.page-about .principle:hover,
.page-about .principle:focus-within,
.page-about .principle:focus-visible {
  background: #FBF6EC;
  box-shadow: inset 0 0 0 2px var(--copper);
  outline: none;
}

.page-about .principle__no {
  display: block;
  margin-bottom: 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--copper);
}

.page-about .principle h3 {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 18px;
  letter-spacing: -0.01em;
  color: var(--ink-900);
}

.page-about .principle p {
  margin: 0;
  font-family: var(--font-body);
  font-size: 14.5px;
  line-height: 1.75;
}

.page-about .principles-figure {
  margin: 0;
}

.page-about .principles-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border: var(--about-edge);
  box-shadow: var(--shadow-hard);
}

.page-about .principles-figure figcaption {
  margin-top: 12px;
  font-family: var(--font-body);
  font-size: 13px;
  line-height: 1.7;
  color: var(--ink-500);
}

/* ---------- 承接范围 ---------- */
.page-about .scope-list {
  list-style: none;
  margin: 1.4em 0 0;
  padding: 0;
  max-width: 46em;
  border-top: 2px solid var(--ink-900);
}

.page-about .scope-list li {
  position: relative;
  padding: 16px 0 16px 22px;
  border-bottom: 1px solid var(--sand);
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.78;
}

.page-about .scope-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 24px;
  width: 10px;
  height: 2px;
  background: var(--cinnabar);
}

.page-about .scope-list strong {
  display: block;
  margin-bottom: 4px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 15.5px;
  color: var(--ink-900);
}

/* ---------- 业务单元 ---------- */
.page-about .units-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 30px;
}

.page-about .unit-list {
  display: grid;
  gap: 2px;
  margin: 1.8em 0;
  background: var(--ink-700);
  border: 2px solid var(--ink-500);
}

.page-about .unit {
  background: var(--ink-900);
  padding: 20px 20px 22px;
}

.page-about .unit__meta {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--copper-light);
}

.page-about .unit h3 {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 19px;
  letter-spacing: -0.01em;
  color: var(--cream);
}

.page-about .unit p {
  margin: 0;
  max-width: none;
  font-family: var(--font-body);
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--sand);
}

.page-about .units-figure {
  margin: 0;
}

.page-about .units-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border: 2px solid var(--ink-500);
  box-shadow: var(--shadow-lift);
}

.page-about .units-figure figcaption {
  margin-top: 12px;
  font-family: var(--font-body);
  font-size: 13px;
  line-height: 1.7;
  color: var(--silver);
}

/* ---------- 覆盖数据 ---------- */
.page-about .cover-stats {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 2px;
  margin: 1.8em 0 2em;
  padding: 0;
  background: var(--ink-900);
  border: var(--about-edge);
  max-width: 46em;
}

.page-about .cover-stats li {
  background: var(--cream);
  padding: 20px 18px 22px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .cover-stats__num {
  font-family: var(--font-mono);
  font-size: clamp(30px, 5vw, 42px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--ink-900);
  font-variant-numeric: tabular-nums;
}

.page-about .cover-stats__label {
  font-family: var(--font-body);
  font-size: 13.5px;
  color: var(--ink-500);
}

.page-about .cover-share {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  align-items: start;
  margin-top: 1.4em;
}

.page-about .cover-dots {
  display: block;
  width: 100%;
  max-width: 230px;
  height: auto;
}

.page-about .cover-share__text p {
  margin: 0 0 0.9em;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.8;
  max-width: 32em;
}

.page-about .cover-share__figure {
  font-family: var(--font-mono) !important;
  font-size: 40px !important;
  font-weight: 700;
  line-height: 1 !important;
  letter-spacing: -0.02em;
  color: var(--ink-900);
  margin-bottom: 0.5em !important;
  font-variant-numeric: tabular-nums;
}

.page-about .cover-share__note {
  padding-left: 16px;
  border-left: 3px solid var(--copper);
  color: var(--ink-700);
  font-size: 14px !important;
}

/* ---------- 时间轴 ---------- */
.page-about .timeline {
  list-style: none;
  position: relative;
  margin: 0;
  padding: 6px 0 0 30px;
  max-width: 52em;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 10px;
  bottom: 14px;
  width: 2px;
  background: linear-gradient(180deg, var(--copper), var(--ink-500));
}

.page-about .phase {
  position: relative;
  padding-bottom: 32px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 6px;
}

.page-about .phase::before {
  content: "";
  position: absolute;
  left: -30px;
  top: 7px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--cream);
  border: 3px solid var(--copper);
  box-sizing: border-box;
  transition: background var(--t), border-color var(--t), box-shadow var(--t);
}

.page-about .phase:hover::before,
.page-about .phase:focus-within::before,
.page-about .phase:focus-visible::before {
  background: var(--copper-light);
  border-color: var(--ink-900);
  box-shadow: 0 0 0 5px rgba(176, 132, 47, 0.18);
}

.page-about .phase:focus-visible {
  outline: none;
}

.page-about .phase__year {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--copper);
  max-width: none;
}

.page-about .phase__body h3 {
  margin: 2px 0 8px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 19px;
  letter-spacing: -0.01em;
  color: var(--ink-900);
}

.page-about .phase__body p {
  margin: 0 0 0.8em;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.8;
  max-width: 36em;
}

.page-about .phase__gain {
  display: inline-block;
  padding: 6px 12px;
  border: 1px solid var(--sand);
  background: rgba(232, 220, 198, 0.5);
  font-size: 13px !important;
  color: var(--ink-700);
}

/* ---------- 资质 ---------- */
.page-about .cred-list {
  list-style: none;
  margin: 0 0 1.4em;
  padding: 0;
  display: grid;
  gap: 2px;
  background: var(--ink-900);
  border: var(--about-edge);
  max-width: 48em;
}

.page-about .cred-list li {
  display: grid;
  grid-template-columns: 1fr;
  gap: 6px;
  background: var(--cream);
  padding: 16px 18px;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.75;
}

.page-about .cred-list__tag {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--copper);
}

/* ---------- 伙伴 ---------- */
.page-about .partner-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
  margin-top: 1.4em;
}

.page-about .partner {
  padding: 20px 20px 22px;
  border: var(--about-edge);
  background: var(--cream);
  box-shadow: var(--shadow-hard);
  transition: transform var(--t), box-shadow var(--t);
}

.page-about .partner:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lift);
}

.page-about .partner h3 {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 18px;
  color: var(--ink-900);
}

.page-about .partner h3::after {
  content: "";
  display: block;
  width: 26px;
  height: 3px;
  margin-top: 10px;
  background: var(--copper);
}

.page-about .partner p {
  margin: 0;
  max-width: none;
  font-family: var(--font-body);
  font-size: 14.5px;
  line-height: 1.78;
}

/* ---------- 结尾 ---------- */
.page-about .about-cta {
  background: var(--ink-900);
  color: var(--cream);
  border-top: 4px solid var(--copper);
  padding: clamp(40px, 6vw, 72px) 0;
}

.page-about .about-cta__inner {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
  align-items: center;
}

.page-about .about-cta h2 {
  margin: 10px 0 16px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(22px, 3vw, 30px);
  line-height: 1.28;
  letter-spacing: -0.01em;
  color: var(--cream);
}

.page-about .about-cta__text p {
  margin: 0;
  max-width: 40em;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.85;
  color: var(--sand);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

.page-about .about-cta__actions .btn {
  min-width: 168px;
  text-align: center;
}

/* ---------- 响应式 ---------- */
@media (min-width: 700px) {
  .page-about .principles {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .page-about .cover-share {
    grid-template-columns: 230px minmax(0, 1fr);
    gap: 32px;
    align-items: center;
  }

  .page-about .cred-list li {
    grid-template-columns: 7.5em 1fr;
    align-items: baseline;
    gap: 14px;
  }

  .page-about .partner-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-cta__inner {
    grid-template-columns: minmax(0, 1fr) auto;
  }
}

@media (min-width: 900px) {
  .page-about .about-open {
    grid-template-columns: minmax(0, 0.68fr) minmax(0, 1fr);
  }

  .page-about .about-open__visual {
    min-height: 100%;
  }

  .page-about .about-open__visual img {
    min-height: 100%;
    height: 100%;
  }

  .page-about .about-open__text {
    padding: clamp(40px, 4.5vw, 64px) clamp(28px, 4vw, 56px);
  }

  .page-about .phase {
    grid-template-columns: 8.5em minmax(0, 1fr);
    gap: 8px 30px;
  }

  .page-about .phase__year {
    text-align: right;
    padding-top: 3px;
  }

  .page-about .phase::before {
    left: -30px;
  }
}

@media (min-width: 1024px) {
  .page-about .principles {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .principles-layout {
    grid-template-columns: minmax(0, 1fr) 308px;
    gap: 36px;
    align-items: start;
  }

  .page-about .units-layout {
    grid-template-columns: minmax(0, 1fr) 360px;
    gap: 44px;
    align-items: start;
  }

  .page-about .units-figure {
    position: sticky;
    top: 100px;
  }
}

@media (max-width: 420px) {
  .page-about .about-chapter h2 {
    gap: 10px;
    font-size: 21px;
  }

  .page-about .about-chapter h2::before {
    width: 20px;
  }

  .page-about .cover-share__figure {
    font-size: 34px !important;
  }
}
<<<END>>>