.page-about {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  padding-top: clamp(20px, 4vw, 40px);
  overflow-x: hidden;
}

.page-about .about-wrap {
  box-sizing: border-box;
  width: 100%;
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.page-about .breadcrumb {
  margin-bottom: clamp(20px, 3vw, 36px);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 44px);
  align-items: start;
  padding-bottom: clamp(32px, 5vw, 56px);
}

.page-about .eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ochre);
}

.page-about .about-hero__title {
  margin: 14px 0 20px;
  font-family: var(--font-display);
  font-weight: 200;
  font-size: clamp(32px, 5.6vw, 66px);
  line-height: 1.08;
  letter-spacing: -0.03em;
  color: var(--ink);
}

.page-about .about-hero__title em {
  font-style: normal;
  font-weight: 800;
  color: var(--ochre);
}

.page-about .about-hero__intro {
  max-width: 62ch;
  margin: 0 0 26px;
  font-size: clamp(16px, 1.4vw, 18px);
  line-height: 1.8;
  color: var(--ink);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-facts {
  box-sizing: border-box;
  border: var(--line) solid var(--ink);
  box-shadow: var(--shadow-hard);
  background: var(--shell);
  padding: 16px 20px 6px;
  transform: rotate(-1.4deg);
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .about-facts:hover {
  transform: rotate(0deg);
  box-shadow: 12px 12px 0 var(--ink);
}

.page-about .about-facts__item {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 12px 0;
  border-bottom: 1px solid rgba(34, 26, 21, 0.18);
}

.page-about .about-facts__item:last-child {
  border-bottom: 0;
}

.page-about .about-facts__num {
  min-width: 3.4ch;
  font-family: var(--font-mono);
  font-size: 27px;
  font-weight: 600;
  line-height: 1;
  color: var(--ochre);
}

.page-about .about-facts__label {
  font-size: 14px;
  line-height: 1.55;
  color: var(--ink);
}

/* ---------- 图片通用 ---------- */

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

.page-about .figure__media {
  overflow: hidden;
  border: var(--line) solid var(--ink);
  background: var(--petro);
}

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

.page-about .figure__caption {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--river);
}

.page-about .about-banner {
  margin-bottom: clamp(8px, 2vw, 18px);
}

/* ---------- 章节骨架 ---------- */

.page-about .about-section {
  padding: clamp(36px, 6vw, 72px) 0;
  border-top: var(--line) solid var(--ink);
}

.page-about .section-label {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--ochre);
}

.page-about h2 {
  margin: 0 0 16px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(24px, 3.4vw, 40px);
  line-height: 1.18;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-about h3 {
  margin: 0 0 10px;
  font-size: clamp(18px, 1.9vw, 21px);
  font-weight: 700;
  line-height: 1.32;
  color: var(--ink);
}

.page-about .about-lede {
  max-width: 64ch;
  margin: 0 0 22px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink);
}

/* ---------- 日常运转 ---------- */

.page-about .about-ops {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(18px, 2.4vw, 26px);
}

.page-about .about-ops__item {
  border-top: 3px solid var(--ochre);
  padding-top: 14px;
}

.page-about .about-ops__item:nth-child(2) {
  border-top-color: var(--goji);
}

.page-about .about-ops__item:nth-child(3) {
  border-top-color: var(--sand);
}

.page-about .about-ops__item:nth-child(4) {
  border-top-color: var(--river);
}

.page-about .about-ops__num {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.12em;
  color: var(--river);
}

.page-about .about-ops__item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--ink);
}

/* ---------- 发展历程 ---------- */

.page-about .about-timeline__figure {
  margin: 0 0 clamp(28px, 4vw, 44px);
}

.page-about .about-timeline__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(18px, 3vw, 40px);
  align-items: start;
}

.page-about .about-years {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.page-about .about-years__link {
  display: inline-block;
  padding: 4px 10px 4px 12px;
  border-left: 4px solid transparent;
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 600;
  letter-spacing: -0.02em;
  text-decoration: none;
  color: var(--ink);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-years__link:hover,
.page-about .about-years__link:focus-visible {
  color: var(--goji);
  border-left-color: var(--sand);
  background: var(--petro);
}

.page-about .about-era {
  padding-bottom: clamp(24px, 3vw, 36px);
  margin-bottom: clamp(24px, 3vw, 36px);
  border-bottom: var(--line) solid var(--ink);
}

.page-about .about-era:last-child {
  padding-bottom: 0;
  margin-bottom: 0;
  border-bottom: 0;
}

.page-about .about-era__year {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(52px, 9vw, 96px);
  line-height: 0.9;
  letter-spacing: -0.05em;
  color: var(--ochre);
  transition: color var(--dur) var(--ease);
}

.page-about .about-era:hover .about-era__year {
  color: var(--goji);
}

.page-about .about-era p {
  max-width: 62ch;
  margin: 0;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--ink);
}

/* ---------- 黄河曲线停顿 ---------- */

.page-about .about-river {
  margin: clamp(8px, 2vw, 20px) 0 0;
  line-height: 0;
}

.page-about .about-river svg {
  display: block;
  width: 100%;
  height: clamp(80px, 13vw, 170px);
}

.page-about .about-river path {
  fill: none;
  stroke-width: 2;
  vector-effect: non-scaling-stroke;
}

.page-about .about-river path:nth-child(1) {
  stroke: var(--ochre);
}

.page-about .about-river path:nth-child(2) {
  stroke: var(--river);
  stroke-dasharray: 6 8;
}

/* ---------- 团队 ---------- */

.page-about .about-team__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 44px);
  margin-top: 26px;
  align-items: start;
}

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

.page-about .about-roles {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-role {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding: 12px 14px;
  background: var(--shell);
  border-left: 6px solid var(--ochre);
}

.page-about .about-role:nth-child(2) {
  border-left-color: var(--goji);
}

.page-about .about-role:nth-child(3) {
  border-left-color: var(--sand);
}

.page-about .about-role:nth-child(4) {
  border-left-color: var(--river);
}

.page-about .about-role:nth-child(5) {
  border-left-color: var(--night);
}

.page-about .about-role__num {
  min-width: 2.4ch;
  font-family: var(--font-mono);
  font-size: 28px;
  font-weight: 700;
  line-height: 1;
  color: var(--ochre-deep);
}

.page-about .about-role__name {
  display: block;
  margin-bottom: 3px;
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .about-role__desc {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--ink);
}

/* ---------- 企业服务色带 ---------- */

.page-about .about-band {
  background: var(--ochre);
  color: var(--shell);
  border-top: var(--line) solid var(--ink);
  border-bottom: var(--line) solid var(--ink);
  padding: clamp(36px, 6vw, 72px) 0;
}

.page-about .about-band h2 {
  color: var(--shell);
}

.page-about .about-band .section-label {
  color: var(--sand);
}

.page-about .about-band .about-lede {
  color: var(--shell);
}

.page-about .about-ent__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 40px);
  margin-top: 24px;
  align-items: start;
}

.page-about .about-kpis {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-kpi {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding-top: 10px;
  border-top: 1px solid rgba(251, 246, 236, 0.4);
}

.page-about .about-kpi__num {
  min-width: 4ch;
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 700;
  line-height: 1;
  color: var(--shell);
}

.page-about .about-kpi__text {
  font-size: 14px;
  line-height: 1.62;
  color: var(--shell);
}

.page-about .about-service {
  box-sizing: border-box;
  margin-bottom: 12px;
  background: var(--shell);
  color: var(--ink);
  border: var(--line) solid var(--ink);
  box-shadow: 4px 4px 0 var(--night);
}

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

.page-about .about-service summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 14px 18px;
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
  cursor: pointer;
  list-style: none;
  transition: background var(--dur) var(--ease);
}

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

.page-about .about-service summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 20px;
  line-height: 1;
  color: var(--goji);
}

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

.page-about .about-service[open] summary {
  background: var(--petro);
}

.page-about .about-service summary:focus-visible {
  outline: 2px solid var(--sand);
  outline-offset: -4px;
}

.page-about .about-service__body {
  padding: 0 18px 16px;
}

.page-about .about-service__body p {
  margin: 0 0 8px;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--ink);
}

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

/* ---------- 协作与质量 ---------- */

.page-about .about-quality__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 36px);
  margin-top: 22px;
}

.page-about .about-status {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin-top: 6px;
}

.page-about .about-status__item {
  box-sizing: border-box;
  padding: 12px 10px;
  border: var(--line) solid var(--ink);
  background: var(--shell);
  border-top-width: 6px;
}

.page-about .about-status__item--done {
  border-top-color: var(--river);
}

.page-about .about-status__item--doing {
  border-top-color: var(--sand);
}

.page-about .about-status__item--todo {
  border-top-color: var(--goji);
}

.page-about .about-status__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 700;
  line-height: 1.1;
  color: var(--ink);
}

.page-about .about-status__label {
  display: block;
  margin-top: 4px;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--river);
}

.page-about .about-quality__note {
  margin: 18px 0 0;
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--ink);
}

/* ---------- 下一步 ---------- */

.page-about .about-next__list {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
}

.page-about .about-next__item {
  border-top: 3px solid var(--ink);
  padding-top: 14px;
}

.page-about .about-next__item p {
  margin: 0;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.78;
  color: var(--ink);
}

/* ---------- 结尾入口 ---------- */

.page-about .about-outro {
  padding: clamp(36px, 6vw, 64px) 0 clamp(48px, 7vw, 88px);
}

.page-about .about-outro__list {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  border-top: var(--line) solid var(--ink);
}

.page-about .about-outro__link {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr) auto;
  gap: 12px;
  align-items: center;
  padding: 16px 6px;
  border-bottom: var(--line) solid var(--ink);
  text-decoration: none;
  color: var(--ink);
  transition: background var(--dur) var(--ease), padding-left var(--dur) var(--ease);
}

.page-about .about-outro__link:hover,
.page-about .about-outro__link:focus-visible {
  background: var(--petro);
  padding-left: 14px;
}

.page-about .about-outro__idx {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--ochre);
}

.page-about .about-outro__name {
  font-size: clamp(17px, 2vw, 21px);
  font-weight: 700;
  line-height: 1.3;
}

.page-about .about-outro__desc {
  display: block;
  margin-top: 3px;
  font-size: 13.5px;
  font-weight: 400;
  line-height: 1.55;
  color: var(--river);
}

.page-about .about-outro__arrow {
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--goji);
}

/* ---------- 响应式 ---------- */

@media (min-width: 780px) {
  .page-about .about-ops {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-ops__item:nth-child(even) {
    margin-top: 26px;
  }

  .page-about .about-next__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px;
  }

  .page-about .about-quality__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  }
}

@media (min-width: 860px) {
  .page-about .about-timeline__grid {
    grid-template-columns: minmax(0, 150px) minmax(0, 1fr);
    gap: clamp(28px, 4vw, 56px);
  }

  .page-about .about-years {
    flex-direction: column;
    gap: 4px;
  }

  .page-about .about-years__link {
    font-size: 30px;
  }

  .page-about .about-outro__link {
    grid-template-columns: 56px minmax(0, 1fr) auto;
    gap: 16px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.55fr) minmax(0, 0.85fr);
  }

  .page-about .about-team__grid {
    grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  }

  .page-about .about-ent__grid {
    grid-template-columns: minmax(0, 0.82fr) minmax(0, 1.18fr);
  }
}

@media (min-width: 1080px) {
  .page-about .about-years {
    position: sticky;
    top: 24px;
  }

  .page-about .about-ent__aside {
    position: sticky;
    top: 24px;
  }
}

@media (max-width: 919px) {
  .page-about .about-facts {
    transform: none;
    box-shadow: var(--shadow-soft);
  }

  .page-about .about-facts:hover {
    transform: none;
    box-shadow: var(--shadow-soft);
  }
}

@media (max-width: 480px) {
  .page-about .about-status {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 6px;
  }

  .page-about .about-status__item {
    padding: 10px 6px;
  }

  .page-about .about-status__num {
    font-size: 20px;
  }

  .page-about .about-status__label {
    font-size: 12px;
  }

  .page-about .about-outro__link {
    grid-template-columns: 32px minmax(0, 1fr) auto;
    gap: 8px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-facts,
  .page-about .about-facts:hover,
  .page-about .about-years__link,
  .page-about .about-outro__link,
  .page-about .about-service summary,
  .page-about .about-era__year {
    transition: none;
  }

  .page-about .about-facts,
  .page-about .about-facts:hover {
    transform: none;
  }
}
<<<END>>>