.page-about {
  --about-line: rgba(143, 166, 178, 0.22);
  --about-card: #0A2B23;
  --about-cut: 20px;
  --about-gap: clamp(64px, 10vw, 128px);

  background: var(--ink-deep);
  color: var(--strong);
  overflow-x: hidden;
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb {
  padding-top: calc(var(--header-h) + 26px);
  padding-bottom: 10px;
}

.page-about .breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--steel);
}

.page-about .breadcrumb-list li + li::before {
  content: "/";
  margin: 0 8px;
  color: var(--steel);
  opacity: 0.45;
}

.page-about .breadcrumb-list a {
  color: var(--steel-light);
  text-decoration: none;
  transition: color var(--dur) var(--ease);
}

.page-about .breadcrumb-list a:hover {
  color: var(--orange);
}

/* ---------- 首屏拼贴 ---------- */
.page-about .about-hero {
  position: relative;
  padding-bottom: clamp(44px, 7vw, 92px);
}

.page-about .about-hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(34px, 5vw, 60px);
  align-items: end;
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-size: clamp(30px, 6vw, 58px);
  font-weight: 900;
  line-height: 1.14;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .about-lead {
  margin: 20px 0 0;
  max-width: 42em;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.78;
  color: var(--steel-light);
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.page-about .about-hero-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--about-line);
  border: 1px solid var(--about-line);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--about-cut)), calc(100% - var(--about-cut)) 100%, 0 100%);
}

.page-about .hero-stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 20px 16px;
  background: var(--ink-3);
}

.page-about .hero-stat-num {
  font-size: clamp(24px, 3.6vw, 34px);
  font-weight: 700;
  line-height: 1;
  color: var(--orange);
  font-variant-numeric: tabular-nums;
}

.page-about .hero-stat-label {
  font-size: 12.5px;
  line-height: 1.5;
  color: var(--steel);
}

/* ---------- 主布局：左索引 + 右内容 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(30px, 5vw, 52px);
  padding-bottom: clamp(72px, 10vw, 140px);
}

.page-about .toc {
  display: flex;
  gap: 6px;
  overflow-x: auto;
  padding-bottom: 8px;
  scrollbar-width: none;
}

.page-about .toc::-webkit-scrollbar {
  display: none;
}

.page-about .toc .index-label {
  display: none;
  margin: 0 0 10px;
}

.page-about .toc-link {
  flex: 0 0 auto;
  display: block;
  padding: 8px 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--steel);
  text-decoration: none;
  white-space: nowrap;
  border-left: 2px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .toc-link:hover {
  color: var(--paper);
}

.page-about .toc-link[aria-current="true"] {
  color: var(--orange);
  border-left-color: var(--orange);
  background: rgba(255, 107, 26, 0.07);
}

/* ---------- 内容区块 ---------- */
.page-about .about-block {
  scroll-margin-top: calc(var(--header-solid-h) + 28px);
}

.page-about .about-main-col > .about-block + .about-block,
.page-about .about-main-col > .about-block + .about-figure--wide {
  margin-top: var(--about-gap);
}

.page-about .about-block > .index-label {
  margin: 0 0 10px;
}

.page-about .about-block > .display-2 {
  margin: 0 0 18px;
  max-width: 22em;
  font-size: clamp(24px, 3.6vw, 38px);
  font-weight: 900;
  line-height: 1.24;
  letter-spacing: -0.015em;
  color: var(--paper);
}

.page-about .about-block > .prose {
  margin: 0 0 28px;
  max-width: 58em;
  color: var(--steel-light);
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  position: relative;
  margin: 34px 0 0;
  padding: 0 0 0 34px;
  list-style: none;
  display: grid;
  gap: clamp(30px, 4.5vw, 52px);
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(
    to bottom,
    var(--orange) 0%,
    rgba(143, 166, 178, 0.32) 18%,
    rgba(143, 166, 178, 0.32) 84%,
    rgba(143, 166, 178, 0) 100%
  );
}

.page-about .tl-item {
  position: relative;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -34px;
  top: 6px;
  width: 15px;
  height: 15px;
  background: var(--ink-deep);
  border: 2px solid var(--orange);
}

.page-about .tl-year {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(22px, 3.2vw, 30px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--orange);
  font-variant-numeric: tabular-nums;
}

.page-about .tl-title {
  margin: 10px 0 8px;
  font-size: clamp(17px, 2vw, 21px);
  font-weight: 700;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .tl-text {
  margin: 0;
  max-width: 46em;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--steel-light);
}

.page-about .tl-meta {
  margin: 12px 0 0;
  padding-top: 10px;
  border-top: 1px dashed var(--about-line);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--steel);
}

/* ---------- 斜线分隔 ---------- */
.page-about .about-rule {
  margin-top: clamp(44px, 6vw, 72px);
  color: rgba(143, 166, 178, 0.34);
}

.page-about .about-rule svg {
  display: block;
  width: 100%;
  height: 36px;
}

/* ---------- 图片位 ---------- */
.page-about .about-figure {
  margin: 0 0 30px;
}

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

.page-about .about-figure img,
.page-about .workflow-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border: 1px solid var(--about-line);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--about-cut)), calc(100% - var(--about-cut)) 100%, 0 100%);
}

.page-about .about-figure--wide img {
  aspect-ratio: 3 / 2;
}

.page-about .about-figure .media-caption,
.page-about .workflow-figure .media-caption {
  display: block;
  margin-top: 12px;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--steel);
}

/* ---------- 团队切换 ---------- */
.page-about .team-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 22px;
}

.page-about .team-tab {
  padding: 9px 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--steel-light);
  background: transparent;
  border: 1px solid var(--about-line);
  cursor: pointer;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 10px), calc(100% - 10px) 100%, 0 100%);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .team-tab:hover {
  color: var(--paper);
  border-color: var(--orange);
}

.page-about .team-tab[aria-pressed="true"],
.page-about .team-tab.is-active {
  color: var(--ink);
  background: var(--orange);
  border-color: var(--orange);
  font-weight: 700;
}

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

.page-about .team-card {
  padding: 24px 20px 22px;
  background: var(--about-card);
  border: 1px solid var(--about-line);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--about-cut)), calc(100% - var(--about-cut)) 100%, 0 100%);
}

.page-about .team-card.is-hidden {
  display: none;
}

.page-about .team-count {
  margin: 0;
  font-size: clamp(30px, 4vw, 42px);
  font-weight: 700;
  line-height: 1;
  color: var(--orange);
  font-variant-numeric: tabular-nums;
}

.page-about .team-role {
  margin: 12px 0 10px;
  font-size: 18px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .team-desc {
  margin: 0 0 14px;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--steel-light);
}

.page-about .team-list {
  margin: 0;
  padding: 14px 0 0;
  list-style: none;
  border-top: 1px dashed var(--about-line);
  display: grid;
  gap: 8px;
}

.page-about .team-list li {
  position: relative;
  padding-left: 16px;
  font-size: 13.5px;
  line-height: 1.65;
  color: var(--steel);
}

.page-about .team-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 6px;
  height: 6px;
  background: var(--orange);
}

/* ---------- 工作流程 ---------- */
.page-about .workflow-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 4vw, 44px);
  align-items: start;
}

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

.page-about .flow-item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 16px;
  padding: 20px 0;
  border-bottom: 1px solid var(--about-line);
}

.page-about .flow-item:first-child {
  border-top: 1px solid var(--about-line);
}

.page-about .flow-num {
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--orange);
  padding-top: 4px;
  font-variant-numeric: tabular-nums;
}

.page-about .flow-title {
  margin: 0 0 6px;
  font-size: 16.5px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .flow-text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--steel-light);
}

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

/* ---------- 横向覆盖轨道 ---------- */
.page-about .rail-wrap {
  margin-top: 6px;
}

.page-about .rail {
  display: flex;
  gap: 14px;
  overflow-x: auto;
  padding-bottom: 16px;
  scroll-snap-type: x mandatory;
  scrollbar-width: thin;
}

.page-about .rail-item {
  flex: 0 0 min(80vw, 300px);
  scroll-snap-align: start;
}

.page-about .cover-card {
  padding: 22px 20px;
  background: var(--indigo);
  border: 1px solid rgba(143, 166, 178, 0.28);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--about-cut)), calc(100% - var(--about-cut)) 100%, 0 100%);
}

.page-about .cover-num {
  margin: 0;
  font-size: clamp(26px, 3.4vw, 34px);
  font-weight: 700;
  line-height: 1;
  color: var(--orange-soft);
  font-variant-numeric: tabular-nums;
}

.page-about .cover-title {
  margin: 12px 0 8px;
  font-size: 16px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .cover-text {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--steel-light);
}

/* ---------- 长期选择（纸白分区） ---------- */
.page-about .why-panel {
  padding: clamp(28px, 5vw, 60px);
  background: var(--paper);
  color: var(--ink);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 28px), calc(100% - 28px) 100%, 0 100%);
}

.page-about .why-panel .index-label {
  color: #5E7480;
  margin: 0 0 10px;
}

.page-about .why-panel .display-2 {
  margin: 0 0 16px;
  max-width: 20em;
  font-size: clamp(24px, 3.6vw, 36px);
  font-weight: 900;
  line-height: 1.24;
  letter-spacing: -0.015em;
  color: var(--ink);
}

.page-about .why-lead {
  margin: 0 0 30px;
  max-width: 52em;
  font-size: 16px;
  line-height: 1.78;
  color: #3B4A50;
}

.page-about .why-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
}

.page-about .why-item {
  position: relative;
  padding-left: 20px;
}

.page-about .why-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: 9px;
  height: 9px;
  background: var(--orange);
}

.page-about .why-title {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--ink);
}

.page-about .why-text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: #46565C;
}

.page-about .why-note {
  margin: 30px 0 0;
  padding-top: 18px;
  border-top: 1px solid rgba(7, 35, 28, 0.14);
  font-size: 14.5px;
  line-height: 1.78;
  color: #46565C;
}

/* ---------- 合作与联系 ---------- */
.page-about .contact-strip {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: 6px;
  background: var(--about-line);
  border: 1px solid var(--about-line);
}

.page-about .contact-cell {
  padding: 22px 20px;
  background: var(--ink-3);
}

.page-about .contact-cell .index-label {
  margin: 0 0 10px;
}

.page-about .contact-value {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.6;
  color: var(--paper);
  word-break: break-word;
}

.page-about .contact-note {
  margin: 10px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--steel);
}

.page-about .about-cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

/* ---------- 返回顶部 ---------- */
.page-about .about-top {
  position: fixed;
  right: clamp(16px, 3vw, 34px);
  bottom: clamp(16px, 3vw, 34px);
  z-index: 40;
  padding: 11px 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--ink);
  background: var(--orange);
  border: 0;
  cursor: pointer;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 10px), calc(100% - 10px) 100%, 0 100%);
  transition: background-color var(--dur) var(--ease);
}

.page-about .about-top:hover {
  background: var(--orange-soft);
}

/* ---------- 响应式 ---------- */
@media (min-width: 620px) {
  .page-about .tl-item {
    display: grid;
    grid-template-columns: 96px minmax(0, 1fr);
    gap: clamp(18px, 3vw, 34px);
    align-items: start;
  }

  .page-about .tl-title {
    margin-top: 4px;
  }

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

  .page-about .why-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 30px 34px;
  }
}

@media (min-width: 760px) {
  .page-about .team-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .workflow-split {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }

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

@media (min-width: 920px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: clamp(40px, 6vw, 88px);
  }
}

@media (min-width: 1000px) {
  .page-about .about-layout {
    grid-template-columns: 200px minmax(0, 1fr);
    gap: clamp(44px, 6vw, 92px);
  }

  .page-about .about-toc-col {
    position: sticky;
    top: calc(var(--header-solid-h) + 36px);
    align-self: start;
  }

  .page-about .toc {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding-bottom: 0;
    border-left: 1px solid var(--about-line);
  }

  .page-about .toc .index-label {
    display: block;
    padding: 0 0 12px 14px;
  }

  .page-about .toc-link {
    white-space: normal;
    padding: 9px 14px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .toc-link,
  .page-about .team-tab,
  .page-about .about-top {
    transition: none;
  }
}
<<<END>>>