.page-about {
  background: var(--paper);
  color: var(--ink);
  overflow-x: hidden;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-top: clamp(22px, 4vw, 38px);
  color: var(--white);
  background:
    radial-gradient(120% 90% at 100% 0%, rgba(224, 138, 46, 0.16) 0%, rgba(224, 138, 46, 0) 58%),
    radial-gradient(90% 70% at 0% 100%, rgba(127, 168, 155, 0.11) 0%, rgba(127, 168, 155, 0) 62%),
    var(--ink);
}

.page-about .about-hero > .wrap {
  padding-bottom: clamp(28px, 4vw, 46px);
}

.page-about .breadcrumbs__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 clamp(18px, 3vw, 30px);
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--mist);
}

.page-about .breadcrumbs__item[aria-current="page"] {
  color: var(--amber);
}

.page-about .breadcrumbs__link {
  color: var(--mist);
  text-decoration: none;
}

.page-about .breadcrumbs__link:hover,
.page-about .breadcrumbs__link:focus-visible {
  color: var(--white);
}

.page-about .about-hero .eyebrow {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--amber);
}

.page-about .hero-grid {
  display: grid;
  gap: clamp(20px, 3vw, 34px);
}

.page-about .hero-copy h1 {
  margin: 0 0 18px;
  font-family: var(--font-head);
  font-size: clamp(28px, 5.2vw, 50px);
  font-weight: 800;
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-about .about-hero .lede {
  margin: 0;
  max-width: 60ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: rgba(255, 255, 255, 0.78);
}

.page-about .hero-plate {
  background: var(--harbor);
  border-top: 2px solid var(--amber);
  padding: clamp(18px, 2.6vw, 26px);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 22px), calc(100% - 22px) 100%, 0 100%);
}

.page-about .hero-plate__tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: var(--celadon);
}

.page-about .hero-plate__text {
  margin: 12px 0 18px;
  font-size: 14.5px;
  line-height: 1.75;
  color: rgba(255, 255, 255, 0.8);
}

.page-about .hero-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(14px, 2.4vw, 28px);
  margin: clamp(26px, 4vw, 44px) 0 0;
  padding: 0;
}

.page-about .hero-stats__item {
  display: flex;
  flex-direction: column-reverse;
  border-top: 1px solid var(--rule-dark);
  padding-top: 12px;
}

.page-about .hero-stats__label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.06em;
  color: var(--mist);
}

.page-about .hero-stats__value {
  margin: 0;
}

.page-about .hero-stats__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(26px, 3.6vw, 38px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--amber);
}

.page-about .about-hero__scale {
  height: 30px;
  border-bottom: 1px solid var(--rule-dark);
  background-image:
    repeating-linear-gradient(90deg, var(--steel) 0 1px, transparent 1px 18px),
    repeating-linear-gradient(90deg, rgba(169, 184, 200, 0.85) 0 1px, transparent 1px 90px);
  background-repeat: repeat-x, repeat-x;
  background-size: 100% 8px, 100% 18px;
  background-position: left bottom, left bottom;
}

/* ---------- 主体骨架 ---------- */
.page-about .about-body {
  display: grid;
  gap: clamp(22px, 3vw, 42px);
  padding-top: clamp(26px, 4vw, 50px);
  padding-bottom: clamp(40px, 6vw, 80px);
}

.page-about .about-toc {
  display: flex;
  flex-wrap: nowrap;
  gap: 8px;
  align-items: center;
  overflow-x: auto;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--rule);
}

.page-about .toc__title {
  flex: 0 0 auto;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: var(--ink-soft);
}

.page-about .about-toc .toc__list {
  display: flex;
  flex: 0 0 auto;
  gap: 4px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .toc__link {
  display: block;
  white-space: nowrap;
  padding: 7px 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--ink-soft);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: color 0.18s ease, border-color 0.18s ease, background-color 0.18s ease;
}

.page-about .toc__link:hover,
.page-about .toc__link:focus-visible,
.page-about .toc__link[aria-current="true"],
.page-about .toc__link[aria-current="location"] {
  color: var(--amber-deep);
  border-bottom-color: var(--amber);
  background: var(--amber-ghost);
}

/* ---------- 章节 ---------- */
.page-about .about-chapters {
  min-width: 0;
}

.page-about .chapter {
  display: grid;
  gap: clamp(16px, 2.4vw, 30px);
  padding-block: clamp(26px, 4vw, 46px);
  border-top: 1px solid var(--rule);
}

.page-about .about-chapters > .chapter:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .chapter__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--amber);
}

.page-about .chapter__title {
  margin: 10px 0 0;
  font-family: var(--font-head);
  font-size: clamp(19px, 2.4vw, 24px);
  font-weight: 800;
  line-height: 1.4;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-about .chapter__main {
  min-width: 0;
}

.page-about .prose p {
  margin: 0 0 14px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
}

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

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

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: clamp(18px, 3vw, 28px) 0 0;
}

.page-about .about-figure .media-frame {
  border: 1px solid var(--rule);
  background: var(--harbor);
  overflow: hidden;
}

.page-about .media-frame__img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-figure .figure-caption {
  margin-top: 10px;
  padding-left: 12px;
  border-left: 2px solid var(--amber);
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.7;
  color: var(--ink-soft);
}

/* ---------- 四步流程 ---------- */
.page-about .flow {
  display: grid;
  gap: 12px;
  margin: clamp(18px, 3vw, 26px) 0 0;
  padding: 0;
  list-style: none;
  counter-reset: step;
}

.page-about .flow__item {
  position: relative;
  background: var(--white);
  border: 1px solid var(--rule);
  border-top: 3px solid var(--celadon-deep);
  padding: 18px 16px 16px;
  transition: border-color 0.2s ease;
}

.page-about .flow__item::before {
  display: block;
  counter-increment: step;
  content: counter(step, decimal-leading-zero);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--amber-deep);
}

.page-about .flow__item:hover {
  border-color: var(--steel);
  border-top-color: var(--amber);
}

.page-about .flow__title {
  margin: 6px 0 8px;
  font-family: var(--font-head);
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .flow__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--ink-soft);
}

/* ---------- 深色切角面板 ---------- */
.page-about .fact-panel {
  margin-top: clamp(20px, 3vw, 30px);
  padding: clamp(20px, 3vw, 30px);
  background: var(--harbor);
  color: var(--white);
  clip-path: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 0 100%);
}

.page-about .fact-panel__label {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: var(--amber);
}

.page-about .fact-panel__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: rgba(255, 255, 255, 0.78);
}

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

.page-about .fact-panel__list li {
  padding-left: 12px;
  border-left: 2px solid var(--celadon-deep);
  font-size: 14px;
  line-height: 1.75;
  color: rgba(255, 255, 255, 0.8);
}

.page-about .fact-panel__num {
  font-family: var(--font-mono);
  font-size: 17px;
  font-weight: 700;
  color: var(--amber);
  margin-right: 4px;
}

.page-about .fact-panel__side .btn {
  margin-top: 16px;
}

.page-about .fact-panel .btn--ghost {
  border-color: var(--rule-dark);
  color: var(--white);
}

.page-about .fact-panel .btn--ghost:hover,
.page-about .fact-panel .btn--ghost:focus-visible {
  border-color: var(--amber);
  color: var(--amber);
}

/* ---------- 折叠说明 ---------- */
.page-about .disclosure {
  margin-top: 18px;
  padding-top: 14px;
  border-top: 1px solid var(--rule-dark);
}

.page-about .disclosure__summary {
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 12.5px;
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: var(--amber);
}

.page-about .disclosure__summary:focus-visible {
  outline: 1px solid var(--amber);
  outline-offset: 3px;
}

.page-about .disclosure__body {
  margin-top: 12px;
  font-size: 14px;
  line-height: 1.85;
  color: rgba(255, 255, 255, 0.76);
}

/* ---------- 服务场景 ---------- */
.page-about .scopes {
  display: grid;
  gap: 16px;
  margin-top: clamp(18px, 3vw, 26px);
}

.page-about .scope {
  padding: 4px 0 4px 16px;
  border-left: 3px solid var(--steel);
}

.page-about .scope:nth-child(1) { border-left-color: var(--amber); }
.page-about .scope:nth-child(2) { border-left-color: var(--celadon); }
.page-about .scope:nth-child(3) { border-left-color: var(--steel); }
.page-about .scope:nth-child(4) { border-left-color: var(--amber-deep); }

.page-about .scope__idx {
  display: block;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.14em;
  color: var(--celadon-deep);
}

.page-about .scope__title {
  margin: 6px 0 6px;
  font-family: var(--font-head);
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .scope__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--ink-soft);
}

/* ---------- 发展历程 ---------- */
.page-about .track {
  display: none;
  width: 100%;
  max-width: 640px;
  height: auto;
  margin: clamp(16px, 3vw, 24px) 0 0;
  color: var(--steel);
}

.page-about .track__line {
  stroke: currentColor;
  stroke-width: 1;
}

.page-about .track__tick {
  stroke: var(--steel);
  stroke-width: 1;
}

.page-about .track__dot {
  fill: var(--amber);
}

.page-about .stages {
  display: grid;
  gap: 14px;
  margin-top: clamp(18px, 3vw, 28px);
}

.page-about .stage {
  position: relative;
  padding: 20px 22px;
  background: var(--white);
  border: 1px solid var(--rule);
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.page-about .stage::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: var(--cut);
  height: var(--cut);
  background: var(--paper);
  clip-path: polygon(0 0, 100% 0, 100% 100%);
}

.page-about .stage:hover,
.page-about .stage:focus-within {
  border-color: var(--amber);
}

.page-about .stage__code {
  display: block;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.12em;
  color: var(--amber-deep);
}

.page-about .stage__title {
  margin: 8px 0 8px;
  font-family: var(--font-head);
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .stage__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--ink-soft);
}

/* ---------- 团队角色 ---------- */
.page-about .roles {
  display: grid;
  gap: 0;
  margin-top: clamp(18px, 3vw, 28px);
  border-top: 1px solid var(--rule);
}

.page-about .role {
  padding: 16px 0;
  border-bottom: 1px solid var(--rule);
}

.page-about .role__title {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--harbor);
}

.page-about .role__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--ink-soft);
}

/* ---------- 联系区 ---------- */
.page-about .contact-panel {
  margin-top: clamp(18px, 3vw, 26px);
  padding: clamp(22px, 4vw, 38px);
  background:
    linear-gradient(150deg, rgba(224, 138, 46, 0.12) 0%, rgba(224, 138, 46, 0) 45%),
    var(--ink);
  color: var(--white);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 26px), calc(100% - 26px) 100%, 0 100%);
}

.page-about .contact-panel__lead {
  margin: 0 0 clamp(18px, 3vw, 26px);
  max-width: 56ch;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(255, 255, 255, 0.82);
}

.page-about .contact-grid {
  display: grid;
  gap: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--rule-dark);
}

.page-about .contact-item__label {
  display: block;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.14em;
  color: var(--mist);
  margin-bottom: 6px;
}

.page-about .contact-item__value {
  display: inline-block;
  max-width: 100%;
  font-family: var(--font-mono);
  font-size: 14px;
  line-height: 1.6;
  color: var(--white);
  text-decoration: none;
  overflow-wrap: anywhere;
  border-bottom: 1px solid transparent;
  transition: color 0.18s ease, border-color 0.18s ease;
}

.page-about .contact-item__value:hover,
.page-about .contact-item__value:focus-visible {
  color: var(--amber);
  border-bottom-color: var(--amber);
}

.page-about .contact-panel__note {
  margin: 20px 0 0;
  padding-left: 12px;
  border-left: 2px solid var(--celadon-deep);
  font-size: 13.5px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.72);
}

.page-about .contact-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 22px;
}

.page-about .contact-panel .btn--ghost {
  border-color: var(--rule-dark);
  color: var(--white);
}

.page-about .contact-panel .btn--ghost:hover,
.page-about .contact-panel .btn--ghost:focus-visible {
  border-color: var(--amber);
  color: var(--amber);
}

.page-about .contact-panel__icp {
  margin: 24px 0 0;
  padding-top: 14px;
  border-top: 1px solid var(--rule-dark);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--mist);
}

/* ---------- 后续入口 ---------- */
.page-about .next-links {
  display: grid;
  gap: 12px;
  margin-top: clamp(18px, 3vw, 26px);
}

.page-about .next-link {
  display: block;
  padding: 16px 18px;
  background: var(--white);
  border: 1px solid var(--rule);
  border-left: 3px solid var(--celadon);
  text-decoration: none;
  transition: border-color 0.2s ease, background-color 0.2s ease;
}

.page-about .next-link:hover,
.page-about .next-link:focus-visible {
  border-left-color: var(--amber);
  background: var(--amber-ghost);
}

.page-about .next-link__title {
  display: block;
  font-family: var(--font-head);
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .next-link__text {
  display: block;
  margin-top: 4px;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--ink-soft);
}

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .scopes {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px 24px;
  }

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

@media (min-width: 720px) {
  .page-about .hero-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .flow {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
  }

  .page-about .roles {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0 28px;
  }
}

@media (min-width: 760px) {
  .page-about .stages {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px 20px;
    padding-bottom: 26px;
  }

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

  .page-about .track {
    display: block;
  }

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

@media (min-width: 900px) {
  .page-about .hero-grid {
    grid-template-columns: minmax(0, 1.55fr) minmax(0, 0.9fr);
    align-items: end;
  }

  .page-about .about-body {
    grid-template-columns: 190px minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-toc {
    position: sticky;
    top: calc(var(--rail-h) + var(--main-h) + 24px);
    display: block;
    overflow: visible;
    padding-bottom: 0;
    border-bottom: 0;
  }

  .page-about .about-toc .toc__list {
    display: block;
    margin-top: 10px;
  }

  .page-about .toc__link {
    padding: 8px 0 8px 12px;
    white-space: normal;
    border-bottom: 0;
    border-left: 2px solid transparent;
  }

  .page-about .toc__link:hover,
  .page-about .toc__link:focus-visible,
  .page-about .toc__link[aria-current="true"],
  .page-about .toc__link[aria-current="location"] {
    border-bottom-color: transparent;
    border-left-color: var(--amber);
  }

  .page-about .chapter {
    grid-template-columns: 200px minmax(0, 1fr);
    gap: clamp(24px, 4vw, 54px);
  }

  .page-about .chapter__head {
    position: sticky;
    top: calc(var(--rail-h) + var(--main-h) + 32px);
    align-self: start;
  }

  .page-about .fact-panel--split {
    display: grid;
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
    gap: clamp(20px, 3vw, 34px);
    align-items: start;
  }

  .page-about .roles {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0 22px;
  }
}

@media (min-width: 1100px) {
  .page-about .flow {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .toc__link,
  .page-about .flow__item,
  .page-about .stage,
  .page-about .next-link,
  .page-about .contact-item__value {
    transition: none;
  }
}
<<<END>>>