.page-about {
  --about-pad-y: clamp(56px, 8vw, 104px);
  --about-gap: clamp(28px, 5vw, 64px);
  --about-rule: rgba(201, 214, 210, 0.16);
  --about-rule-soft: rgba(201, 214, 210, 0.08);
  --about-body: rgba(242, 244, 239, 0.78);
  --about-body-dim: rgba(242, 244, 239, 0.62);

  background: var(--ink);
  color: var(--text);
  font-family: var(--font-body);
  overflow-x: clip;
}

.page-about h2 {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 4vw, 2.5rem);
  line-height: 1.18;
  letter-spacing: -0.015em;
  font-weight: 800;
  color: var(--cream);
  margin: 10px 0 0;
}

.page-about h3 {
  font-family: var(--font-body);
  font-size: clamp(1.02rem, 2vw, 1.16rem);
  font-weight: 600;
  line-height: 1.55;
  color: var(--cream);
  margin: 8px 0 0;
}

.page-about .about-copy {
  margin: 14px 0 0;
  max-width: 60ch;
  font-size: clamp(0.95rem, 1.5vw, 1.02rem);
  line-height: 1.9;
  color: var(--about-body);
}

.page-about .about-section {
  padding: var(--about-pad-y) 0;
}

.page-about .about-head {
  max-width: 46rem;
}

.page-about .about-head .about-copy {
  margin-top: 18px;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 0;
  padding: 18px 0 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-dim);
}

.page-about .breadcrumb li + li::before {
  content: "/";
  margin-right: 10px;
  color: rgba(201, 214, 210, 0.4);
}

.page-about .breadcrumb a {
  color: var(--text-dim);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.22s var(--ease), border-color 0.22s var(--ease);
}

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

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(30px, 5vw, 60px) 0 clamp(48px, 7vw, 96px);
  background:
    radial-gradient(120% 90% at 82% 8%, rgba(72, 240, 208, 0.09), transparent 58%),
    radial-gradient(90% 80% at 4% 96%, rgba(42, 35, 80, 0.5), transparent 62%);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  clip-path: polygon(62% 0, 100% 0, 100% 100%, 36% 100%);
  background: linear-gradient(158deg, rgba(10, 26, 47, 0.62), rgba(42, 35, 80, 0.42));
  pointer-events: none;
}

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

.page-about .about-hero-grid {
  display: grid;
  gap: var(--about-gap);
  align-items: center;
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2rem, 6.2vw, 4.1rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
  font-weight: 800;
  color: var(--cream);
  margin: 14px 0 0;
}

.page-about .about-lede {
  margin: 22px 0 0;
  max-width: 34em;
  font-size: clamp(0.97rem, 1.6vw, 1.1rem);
  line-height: 1.9;
  color: var(--about-body);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin: clamp(28px, 4vw, 44px) 0 0;
  padding: 0;
  border-top: 1px solid var(--about-rule);
}

.page-about .about-facts .fact {
  padding: 14px 16px 14px 0;
  border-bottom: 1px solid var(--about-rule);
}

.page-about .about-facts .fact:nth-child(odd) {
  padding-right: 18px;
  border-right: 1px solid var(--about-rule);
}

.page-about .about-facts .fact:nth-child(even) {
  padding-left: 18px;
}

.page-about .about-facts dt {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text-dim);
}

.page-about .about-facts dd {
  margin: 8px 0 0;
  font-family: var(--font-mono);
  font-size: clamp(1.1rem, 2.4vw, 1.45rem);
  color: var(--cyan);
  letter-spacing: 0.02em;
}

.page-about .about-hero-link {
  margin: 28px 0 0;
}

.page-about .about-hero-link a {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--orange);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 138, 61, 0.45);
  padding-bottom: 3px;
  transition: color 0.22s var(--ease), border-color 0.22s var(--ease);
}

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

.page-about .about-hero-media {
  position: relative;
  margin: 0;
  border-radius: 4px 20px 4px 20px;
  overflow: hidden;
  background: var(--charcoal);
}

.page-about .about-hero-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 5 / 6;
  object-fit: cover;
  filter: saturate(0.88) contrast(1.04);
}

.page-about .about-hero-badge {
  position: absolute;
  left: 0;
  bottom: 16%;
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin: 0;
  padding: 10px 18px 10px 16px;
  background: rgba(10, 26, 47, 0.92);
  border-left: 2px solid var(--orange);
  border-radius: 0 14px 2px 0;
  font-family: var(--font-mono);
}

.page-about .badge-num {
  font-size: 1.15rem;
  color: var(--orange);
  letter-spacing: 0.04em;
}

.page-about .badge-txt {
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--silver);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  background: var(--charcoal);
}

.page-about .team-grid {
  display: grid;
  gap: clamp(30px, 5vw, 56px);
  margin-top: clamp(34px, 5vw, 58px);
  align-items: center;
}

.page-about .team-donut {
  margin: 0;
}

.page-about .donut-stage {
  position: relative;
  width: min(300px, 76vw);
  margin: 0 auto;
  aspect-ratio: 1;
}

.page-about .donut-stage svg {
  display: block;
  width: 100%;
  height: 100%;
}

.page-about .donut-track {
  fill: none;
  stroke: rgba(201, 214, 210, 0.12);
  stroke-width: 26;
}

.page-about .donut-seg {
  fill: none;
  stroke-width: 26;
  transition: stroke-width 0.22s var(--ease), opacity 0.22s var(--ease);
}

.page-about .seg-a {
  stroke: var(--cyan);
}

.page-about .seg-b {
  stroke: var(--orange);
}

.page-about .seg-c {
  stroke: var(--silver);
}

.page-about .donut-center {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  margin: 0;
  pointer-events: none;
}

.page-about .donut-num {
  font-family: var(--font-mono);
  font-size: clamp(2.1rem, 7vw, 3rem);
  line-height: 1;
  color: var(--cream);
}

.page-about .donut-unit {
  margin-top: 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--text-dim);
}

.page-about .team-roles {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .team-role {
  padding: 16px 18px;
  border-left: 2px solid var(--about-rule);
  border-radius: 0 14px 14px 0;
  background: rgba(242, 244, 239, 0.018);
  transition: border-color 0.22s var(--ease), background 0.22s var(--ease), transform 0.22s var(--ease);
}

.page-about .team-role:hover,
.page-about .team-role:focus-within,
.page-about .team-role:focus-visible {
  border-left-color: var(--cyan);
  background: rgba(242, 244, 239, 0.045);
  transform: translateX(4px);
  outline: none;
}

.page-about .role-head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin: 0;
}

.page-about .role-num {
  font-family: var(--font-mono);
  font-size: clamp(1.3rem, 3.4vw, 1.65rem);
  line-height: 1;
  color: var(--cyan);
}

.page-about .role-name {
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 1rem;
  color: var(--cream);
  letter-spacing: 0.02em;
}

.page-about .role-desc {
  margin: 10px 0 0;
  font-size: 0.92rem;
  line-height: 1.82;
  color: var(--about-body-dim);
}

.page-about .team-grid:has(.role-a:hover) .seg-a,
.page-about .team-grid:has(.role-a:focus-within) .seg-a,
.page-about .team-grid:has(.role-b:hover) .seg-b,
.page-about .team-grid:has(.role-b:focus-within) .seg-b,
.page-about .team-grid:has(.role-c:hover) .seg-c,
.page-about .team-grid:has(.role-c:focus-within) .seg-c {
  stroke-width: 32;
}

/* ---------- 流程 ---------- */
.page-about .about-flow {
  background: var(--indigo);
}

.page-about .flow-banner {
  margin: clamp(28px, 4vw, 46px) 0 clamp(30px, 4vw, 48px);
  border-radius: 4px 20px 4px 20px;
  overflow: hidden;
  line-height: 0;
  background: var(--ink);
}

.page-about .flow-banner img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 6;
  object-fit: cover;
  opacity: 0.55;
}

.page-about .flow-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .flow-item {
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.page-about .flow-step {
  padding: 14px 16px;
  background: rgba(11, 43, 38, 0.55);
  border: 1px solid var(--about-rule);
  border-radius: 3px 14px 3px 14px;
  transition: border-color 0.22s var(--ease), background 0.22s var(--ease), transform 0.22s var(--ease);
}

.page-about .flow-step:hover {
  transform: translateY(-4px);
}

.page-about .flow-step[open] {
  border-color: rgba(72, 240, 208, 0.45);
  background: rgba(11, 43, 38, 0.86);
}

.page-about .flow-step summary {
  display: flex;
  flex-direction: column;
  gap: 6px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .step-idx {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--cyan);
}

.page-about .step-name {
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 1rem;
  color: var(--cream);
}

.page-about .step-lead {
  font-size: 0.85rem;
  line-height: 1.7;
  color: var(--about-body-dim);
}

.page-about .step-body {
  margin: 12px 0 0;
  padding-top: 12px;
  border-top: 1px solid var(--about-rule-soft);
  font-size: 0.9rem;
  line-height: 1.85;
  color: var(--about-body);
}

.page-about .flow-arrow {
  display: none;
  color: var(--silver);
}

/* ---------- 时间线 ---------- */
.page-about .about-history {
  background: var(--ink);
}

.page-about .about-timeline {
  list-style: none;
  margin: clamp(34px, 5vw, 58px) 0 0;
  padding: 0;
  position: relative;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 12px;
  bottom: 12px;
  width: 1px;
  background: linear-gradient(180deg,
    rgba(72, 240, 208, 0.55),
    rgba(107, 30, 46, 0.85) 58%,
    rgba(201, 214, 210, 0.14));
}

.page-about .tl-node {
  position: relative;
  padding: 0 0 clamp(34px, 5vw, 54px) 38px;
}

.page-about .tl-node:last-child {
  padding-bottom: 0;
}

.page-about .tl-node::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  background: var(--wine);
  border: 2px solid var(--ink);
  box-shadow: 0 0 0 1px rgba(201, 214, 210, 0.28);
  transition: background 0.22s var(--ease), box-shadow 0.22s var(--ease);
}

.page-about .tl-node:hover::before,
.page-about .tl-node:focus-within::before,
.page-about .tl-node:focus-visible::before {
  background: var(--cyan);
  box-shadow: 0 0 0 1px rgba(72, 240, 208, 0.55), 0 0 16px rgba(72, 240, 208, 0.35);
}

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

.page-about .tl-year {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.05rem, 2.6vw, 1.5rem);
  letter-spacing: 0.1em;
  color: var(--cyan);
  line-height: 1;
}

.page-about .tl-node .about-copy {
  margin-top: 10px;
  max-width: 56ch;
}

.page-about .tl-detail {
  margin: 14px 0 0;
  padding: 12px 16px;
  max-width: 54ch;
  border-left: 2px solid rgba(72, 240, 208, 0.35);
  border-radius: 0 12px 12px 0;
  background: rgba(242, 244, 239, 0.032);
  font-size: 0.9rem;
  line-height: 1.85;
  color: var(--about-body-dim);
  opacity: 0.72;
  transition: opacity 0.22s var(--ease), transform 0.22s var(--ease), border-color 0.22s var(--ease);
}

.page-about .tl-node:hover .tl-detail,
.page-about .tl-node:focus-within .tl-detail,
.page-about .tl-node:focus-visible .tl-detail {
  opacity: 1;
  transform: translateX(6px);
  border-left-color: var(--cyan);
}

.page-about .about-landscape {
  margin: clamp(36px, 5vw, 64px) 0 0;
  border-radius: 4px 20px 4px 20px;
  overflow: hidden;
  background: var(--charcoal);
}

.page-about .about-landscape img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 12 / 5;
  object-fit: cover;
  opacity: 0.72;
}

/* ---------- 版本库 ---------- */
.page-about .about-archive {
  background: var(--night);
}

.page-about .about-archive-grid {
  display: grid;
  gap: clamp(30px, 5vw, 60px);
}

.page-about .archive-copy .about-copy + .about-copy {
  margin-top: 16px;
}

.page-about .archive-lines {
  list-style: none;
  margin: 0;
  padding: clamp(18px, 3vw, 26px) clamp(18px, 3vw, 28px);
  display: grid;
  gap: 2px;
  border: 1px solid var(--about-rule);
  border-radius: 4px 20px 4px 20px;
  background: rgba(11, 43, 38, 0.42);
}

.page-about .archive-lines .data-line {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 18px;
  padding: 12px 0;
  border-bottom: 1px solid var(--about-rule-soft);
  font-family: var(--font-mono);
  font-size: 0.86rem;
  letter-spacing: 0.02em;
}

.page-about .archive-lines .data-line:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .archive-lines .data-line span {
  color: var(--about-body-dim);
}

.page-about .archive-lines .data-line b {
  color: var(--cyan);
  font-weight: 500;
  white-space: nowrap;
}

/* ---------- 用户场景 ---------- */
.page-about .about-audience {
  background: var(--charcoal);
}

.page-about .audience-grid {
  display: grid;
  gap: 2px;
  margin-top: clamp(34px, 5vw, 56px);
  border-top: 1px solid var(--about-rule);
}

.page-about .audience-item {
  padding: clamp(22px, 3.4vw, 34px) 0;
  border-bottom: 1px solid var(--about-rule);
}

.page-about .aud-num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.24em;
  color: var(--text-dim);
}

.page-about .audience-item h3 {
  margin-top: 12px;
}

.page-about .audience-item p:not(.aud-num) {
  margin: 12px 0 0;
  max-width: 42ch;
  font-size: 0.94rem;
  line-height: 1.85;
  color: var(--about-body);
}

.page-about .aud-a {
  box-shadow: inset 3px 0 0 0 rgba(72, 240, 208, 0.7);
  padding-left: 18px;
}

.page-about .aud-b {
  box-shadow: inset 3px 0 0 0 rgba(255, 138, 61, 0.7);
  padding-left: 18px;
}

.page-about .aud-c {
  box-shadow: inset 3px 0 0 0 rgba(201, 214, 210, 0.55);
  padding-left: 18px;
}

/* ---------- 资质 ---------- */
.page-about .about-trust {
  background:
    radial-gradient(100% 80% at 88% 0%, rgba(107, 30, 46, 0.45), transparent 62%),
    var(--ink);
}

.page-about .trust-grid {
  display: grid;
  gap: 1px;
  margin-top: clamp(32px, 5vw, 52px);
  background: var(--about-rule);
  border: 1px solid var(--about-rule);
  border-radius: 4px 20px 4px 20px;
  overflow: hidden;
}

.page-about .trust-item {
  padding: clamp(20px, 3vw, 30px);
  background: rgba(11, 43, 38, 0.86);
  transition: background 0.22s var(--ease), transform 0.22s var(--ease);
}

.page-about .trust-item:hover {
  background: rgba(18, 23, 26, 0.95);
  transform: translateY(-4px);
}

.page-about .trust-label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .trust-body {
  margin: 12px 0 0;
  font-size: 0.93rem;
  line-height: 1.85;
  color: var(--about-body);
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  padding: var(--about-pad-y) 0;
  background: var(--night);
}

.page-about .about-cta h2 {
  max-width: 22ch;
}

.page-about .about-cta .about-copy {
  margin-top: 16px;
}

.page-about .about-cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 28px 0 0;
}

/* ---------- 章节索引轨道 ---------- */
.page-about .about-rail {
  display: none;
}

.page-about .about-rail a {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-decoration: none;
  color: rgba(126, 154, 146, 0.75);
  transition: color 0.22s var(--ease);
}

.page-about .about-rail a:hover,
.page-about .about-rail a:focus-visible,
.page-about .about-rail a.is-active {
  color: var(--cyan);
}

/* ---------- 响应式 ---------- */
@media (min-width: 760px) {
  .page-about .audience-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0 clamp(20px, 3.4vw, 40px);
    border-top: 0;
  }

  .page-about .audience-item {
    border-bottom: 0;
    border-top: 1px solid var(--about-rule);
  }

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

@media (min-width: 900px) {
  .page-about .team-grid {
    grid-template-columns: minmax(0, 0.6fr) minmax(0, 1fr);
  }

  .page-about .about-archive-grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: start;
  }

  .page-about .flow-steps {
    flex-direction: row;
    align-items: flex-start;
    gap: 0;
  }

  .page-about .flow-item {
    flex: 1 1 0;
    flex-direction: row;
    align-items: flex-start;
    min-width: 0;
  }

  .page-about .flow-step {
    flex: 1 1 auto;
    min-width: 0;
    height: 100%;
  }

  .page-about .flow-arrow {
    display: block;
    flex: 0 0 34px;
    width: 34px;
    height: 22px;
    margin: 26px 2px 0;
  }
}

@media (min-width: 960px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.75fr);
    gap: clamp(36px, 5vw, 80px);
  }

  .page-about .about-hero-media img {
    aspect-ratio: 6 / 7;
  }
}

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

@media (min-width: 1560px) {
  .page-about .about-rail {
    display: flex;
    flex-direction: column;
    gap: 12px;
    position: fixed;
    top: 50%;
    right: 20px;
    transform: translateY(-50%);
    z-index: 20;
    padding: 4px 0 4px 12px;
    border-left: 1px solid var(--about-rule);
  }
}

@media (hover: none) {
  .page-about .tl-detail {
    opacity: 1;
    background: rgba(242, 244, 239, 0.045);
  }
}
<<<END>>>