.page-about {
  --about-txt: var(--mist);
  --about-strong: var(--paper);
  --about-rule: rgba(168, 203, 221, 0.18);
  background: var(--ink-deep);
  color: var(--paper);
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb {
  padding-bottom: clamp(18px, 3vw, 28px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: clamp(16px, 3vw, 28px) 0 clamp(40px, 7vw, 88px);
  background:
    radial-gradient(90% 72% at 86% 0%, rgba(25, 227, 255, 0.16), rgba(6, 26, 46, 0) 62%),
    linear-gradient(180deg, var(--ink-deep) 0%, #04121f 100%);
  border-bottom: 1px solid var(--line-cyan);
}

.page-about .about-hero__inner {
  display: grid;
  gap: clamp(26px, 5vw, 52px);
  align-items: end;
}

.page-about .about-hero__title {
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(42px, 8.4vw, 92px);
  line-height: 0.98;
  letter-spacing: -0.02em;
  margin: 12px 0 0;
  color: var(--paper);
}

.page-about .about-hero__paper {
  margin-top: clamp(20px, 3vw, 30px);
  background: var(--paper);
  color: var(--ink-deep);
  border-left: 4px solid var(--flame);
  padding: clamp(18px, 3vw, 28px);
}

.page-about .about-hero__paper p {
  margin: 0;
  max-width: 34em;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
}

.page-about .about-hero__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  list-style: none;
  margin: 16px 0 0;
  padding: 0;
}

.page-about .about-hero__tags .tag {
  padding: 5px 11px;
  border: 1px solid rgba(6, 26, 46, 0.3);
  border-radius: var(--radius-hard);
  background: transparent;
  color: var(--ink-deep);
  font-size: 12px;
  letter-spacing: 0.08em;
}

.page-about .about-hero__media {
  margin: 0;
  border: 1px solid var(--line-cyan);
  background: var(--ink-night);
}

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

.page-about .about-hero__media .media__caption {
  padding: 10px 14px;
  border-top: 1px solid var(--line-soft);
  color: var(--mist);
  font-size: 12px;
  letter-spacing: 0.08em;
}

/* ---------- 分区基底 ---------- */
.page-about .about-section {
  position: relative;
  padding: clamp(44px, 8vw, 96px) 0;
  background: var(--ink-deep);
  color: var(--paper);
  --about-txt: var(--mist);
  --about-strong: var(--paper);
  --about-rule: rgba(168, 203, 221, 0.18);
  border-bottom: 1px solid rgba(168, 203, 221, 0.14);
}

.page-about .about-section--steel {
  background: linear-gradient(160deg, var(--ink-night) 0%, #071d31 64%, var(--ink-deep) 100%);
}

.page-about .about-section--paper {
  background: var(--paper);
  color: var(--ink-deep);
  --about-txt: rgba(6, 26, 46, 0.78);
  --about-strong: var(--ink-deep);
  --about-rule: rgba(6, 26, 46, 0.18);
  border-bottom-color: rgba(6, 26, 46, 0.2);
}

.page-about .about-split {
  display: grid;
  gap: clamp(24px, 4vw, 48px);
}

.page-about .about-rail__index {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.22em;
  color: var(--cyan);
  margin: 0 0 14px;
}

.page-about .about-section--paper .about-rail__index {
  color: var(--flame);
}

.page-about .about-rail h2 {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: clamp(28px, 3.6vw, 44px);
  line-height: 1.06;
  letter-spacing: -0.01em;
  margin: 0;
  color: var(--about-strong);
}

.page-about .about-rail__note {
  margin: 14px 0 0;
  padding-top: 12px;
  max-width: 22em;
  border-top: 1px solid var(--about-rule);
  font-size: 13px;
  line-height: 1.75;
  letter-spacing: 0.04em;
  color: var(--about-txt);
}

.page-about .about-body > * + * {
  margin-top: 20px;
}

.page-about .about-body p {
  margin: 0;
  max-width: 42em;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.85;
  color: var(--about-txt);
}

.page-about .about-body .lead {
  font-size: clamp(18px, 2.1vw, 22px);
  line-height: 1.7;
  color: var(--about-strong);
}

/* ---------- 服务节点 ---------- */
.page-about .node-facts {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-rule);
  border: 1px solid var(--about-rule);
}

.page-about .node-facts li {
  background: var(--ink-deep);
  padding: 16px 18px;
}

.page-about .node-facts__val {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(20px, 2.4vw, 26px);
  letter-spacing: 0.06em;
  color: var(--cyan);
}

.page-about .node-facts__label {
  display: block;
  margin-top: 6px;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--mist);
}

/* ---------- 业务线 ---------- */
.page-about .line-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--about-rule);
}

.page-about .line-item {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 4px 16px;
  padding: 20px 0;
  border-bottom: 1px solid var(--about-rule);
  text-decoration: none;
  color: inherit;
  transition: background var(--dur) var(--ease), padding-left var(--dur) var(--ease);
}

.page-about .line-item:hover,
.page-about .line-item:focus-visible {
  background: rgba(25, 227, 255, 0.07);
  padding-left: 12px;
}

.page-about .line-item__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--flame);
  padding-top: 6px;
}

.page-about .line-item__title {
  display: block;
  font-size: clamp(18px, 2vw, 22px);
  font-weight: 600;
  color: var(--about-strong);
}

.page-about .line-item__desc {
  display: block;
  margin-top: 7px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--about-txt);
}

.page-about .line-item__go {
  grid-column: 2;
  justify-self: start;
  margin-top: 10px;
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--cyan);
}

/* ---------- 服务对象 ---------- */
.page-about .who-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 24px;
}

.page-about .who-card {
  border-top: 2px solid var(--about-rule);
  padding-top: 16px;
}

.page-about .who-card__tag {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--flame);
}

.page-about .who-card h3 {
  margin: 8px 0 8px;
  font-size: 20px;
  line-height: 1.25;
  font-weight: 600;
  color: var(--about-strong);
}

.page-about .who-card p:not(.who-card__tag) {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--about-txt);
}

/* ---------- 协作网络 ---------- */
.page-about .net-media {
  margin: 0;
  border: 1px solid var(--line-cyan);
  background: var(--ink-deep);
}

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

.page-about .net-media .media__caption {
  padding: 10px 14px;
  border-top: 1px solid var(--line-soft);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist);
}

.page-about .net-nodes {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-rule);
  border: 1px solid var(--about-rule);
}

.page-about .net-node {
  background: var(--ink-night);
  padding: 18px;
  transition: background var(--dur) var(--ease);
}

.page-about .net-node:hover,
.page-about .net-node:focus-within {
  background: rgba(25, 227, 255, 0.1);
}

.page-about .net-node__num {
  font-family: var(--font-mono);
  font-size: 30px;
  letter-spacing: 0.04em;
  color: var(--cyan);
}

.page-about .net-node__unit {
  margin-left: 4px;
  font-size: 12px;
  color: var(--mist);
}

.page-about .net-node__name {
  display: block;
  margin-top: 6px;
  font-size: 15px;
  font-weight: 600;
  color: var(--paper);
}

.page-about .net-node__role {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .net-trust {
  margin: 24px 0 0;
  padding: 12px 0 12px 16px;
  border-left: 2px solid var(--gold);
  font-size: 13.5px;
  line-height: 1.85;
  color: var(--mist);
}

/* ---------- 版本演进 ---------- */
.page-about .tl-media {
  margin: 0 0 24px;
  max-width: 360px;
  border: 1px solid var(--line-cyan);
  background: var(--ink-deep);
}

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

.page-about .tl-media .media__caption {
  padding: 10px 14px;
  border-top: 1px solid var(--line-soft);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist);
}

.page-about .tl-index {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  list-style: none;
  margin: 0 0 20px;
  padding: 0;
}

.page-about .tl-index a {
  display: inline-block;
  padding: 5px 13px;
  border: 1px solid var(--about-rule);
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--about-txt);
  text-decoration: none;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

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

.page-about .tl-scroll {
  overflow-x: auto;
  padding-bottom: 14px;
  scroll-snap-type: x proximity;
  border-top: 1px solid var(--about-rule);
}

.page-about .tl-track {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(232px, 1fr);
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .tl-item {
  position: relative;
  border-left: 1px solid var(--about-rule);
  padding: 22px 18px 10px 18px;
  scroll-snap-align: start;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  top: -5px;
  left: -4px;
  width: 8px;
  height: 8px;
  background: var(--steel);
}

.page-about .tl-item--now::before {
  background: var(--flame);
  box-shadow: 0 0 0 4px rgba(255, 77, 46, 0.16);
}

.page-about .tl-item__year {
  font-family: var(--font-mono);
  font-size: 26px;
  letter-spacing: 0.08em;
  color: var(--about-strong);
}

.page-about .tl-item__title {
  display: block;
  margin-top: 6px;
  font-size: 16px;
  font-weight: 600;
  color: var(--cyan);
}

.page-about .tl-item--now .tl-item__title {
  color: var(--flame);
}

.page-about .tl-item__desc {
  display: block;
  margin-top: 8px;
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--about-txt);
}

/* ---------- 团队与服务 ---------- */
.page-about .team-groups {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .team-group {
  border-left: 2px solid var(--steel);
  padding-left: 14px;
}

.page-about .team-group h3 {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 600;
  color: var(--about-strong);
}

.page-about .team-group p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--about-txt);
}

.page-about .about-stats {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-rule);
  border: 1px solid var(--about-rule);
}

.page-about .about-stat {
  background: var(--paper);
  padding: 16px 18px;
}

.page-about .about-stat__val {
  font-family: var(--font-mono);
  font-size: clamp(24px, 3vw, 32px);
  letter-spacing: 0.06em;
  color: var(--ink-deep);
}

.page-about .about-stat__unit {
  margin-left: 4px;
  font-size: 12px;
  color: rgba(6, 26, 46, 0.62);
}

.page-about .about-stat__label {
  display: block;
  margin-top: 6px;
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: rgba(6, 26, 46, 0.66);
}

/* ---------- 结尾入口 ---------- */
.page-about .about-cta {
  background: var(--char);
  border-bottom: 0;
  --about-txt: var(--mist);
  --about-strong: var(--paper);
  --about-rule: rgba(168, 203, 221, 0.2);
}

.page-about .about-cta__inner {
  display: grid;
  gap: 24px;
}

.page-about .about-cta__title {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: clamp(28px, 3.6vw, 44px);
  line-height: 1.08;
  margin: 8px 0 0;
  color: var(--paper);
}

.page-about .about-cta__links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: rgba(168, 203, 221, 0.2);
  border-top: 1px solid rgba(168, 203, 221, 0.2);
  border-bottom: 1px solid rgba(168, 203, 221, 0.2);
}

.page-about .about-cta__link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  background: var(--char);
  padding: 16px 18px;
  color: var(--paper);
  text-decoration: none;
  font-size: 15px;
  letter-spacing: 0.02em;
  transition: color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-cta__link:hover,
.page-about .about-cta__link:focus-visible {
  background: var(--ink-night);
  color: var(--cyan);
}

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .node-facts {
    grid-template-columns: repeat(3, 1fr);
  }

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

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

@media (min-width: 760px) {
  .page-about .line-item {
    grid-template-columns: 44px 1fr auto;
    align-items: start;
  }

  .page-about .line-item__go {
    grid-column: 3;
    margin-top: 6px;
  }

  .page-about .who-grid {
    grid-template-columns: 1fr 1fr;
  }

  .page-about .who-card:nth-child(even) {
    margin-top: 44px;
  }

  .page-about .net-nodes {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__inner {
    grid-template-columns: 5fr 7fr;
  }

  .page-about .about-split {
    grid-template-columns: 5fr 7fr;
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: 104px;
  }

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

  .page-about .about-cta__inner {
    grid-template-columns: 5fr 7fr;
    align-items: center;
  }

  .page-about .tl-media {
    margin-left: auto;
    max-width: 380px;
  }

  .page-about .net-node__role {
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    transition: max-height 300ms var(--ease), opacity 220ms var(--ease), margin-top 220ms var(--ease);
    margin-top: 0;
  }

  .page-about .net-node:hover .net-node__role,
  .page-about .net-node:focus-within .net-node__role,
  .page-about .net-node:focus .net-node__role {
    max-height: 140px;
    opacity: 1;
    margin-top: 8px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .line-item,
  .page-about .net-node,
  .page-about .net-node__role,
  .page-about .about-cta__link,
  .page-about .tl-index a {
    transition: none;
  }
}
<<<END>>>