.page-about {
  --about-rail: 220px;
  --about-line: rgba(111, 227, 225, .2);
  --about-edge: rgba(169, 188, 203, .14);

  padding-block: clamp(20px, 4vw, 44px) clamp(40px, 7vw, 88px);
  background:
    radial-gradient(120% 70% at 88% -8%, rgba(47, 123, 217, .24) 0%, transparent 62%),
    radial-gradient(90% 55% at 6% 108%, rgba(111, 227, 225, .1) 0%, transparent 60%),
    var(--night);
  color: var(--white);
}

.page-about .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0 0 clamp(16px, 2.6vw, 26px);
  padding: 0;
  list-style: none;
  font-size: 12.5px;
  color: var(--mute);
}

.page-about .breadcrumb a {
  color: var(--mute);
  text-decoration: none;
}

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

.page-about .breadcrumb__item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.page-about .breadcrumb__sep {
  color: rgba(169, 188, 203, .5);
}

.page-about .breadcrumb__current {
  color: var(--white);
}

/* ---------- 分屏外壳 ---------- */
.page-about .about-shell {
  display: block;
}

.page-about .about-rail {
  position: sticky;
  top: 8px;
  z-index: 6;
  margin-bottom: clamp(22px, 4vw, 34px);
  padding: 14px 16px 16px;
  border-radius: var(--r-lg);
  background: var(--paper);
  color: var(--ink);
  box-shadow: 0 14px 34px rgba(3, 12, 24, .34);
}

.page-about .about-rail__label {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--ink);
  opacity: .62;
}

.page-about .about-rail__years {
  display: flex;
  gap: 10px;
  margin: 0;
  padding: 0 0 4px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-rail__years li {
  flex: 0 0 auto;
}

.page-about .about-rail__years a {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 8px 12px;
  border-radius: var(--r-md);
  border: 1px solid rgba(10, 26, 43, .14);
  color: var(--ink);
  text-decoration: none;
  white-space: nowrap;
  transition: background .3s var(--ease), color .3s var(--ease), border-color .3s var(--ease);
}

.page-about .about-rail__years a:hover,
.page-about .about-rail__years a:focus-visible {
  background: var(--ink);
  border-color: var(--ink);
  color: var(--paper);
}

.page-about .about-year {
  font-family: var(--font-mono);
  font-size: 17px;
  font-weight: 700;
  letter-spacing: .06em;
  color: var(--blue);
  transition: color .3s var(--ease);
}

.page-about .about-rail__years a:hover .about-year,
.page-about .about-rail__years a:focus-visible .about-year {
  color: var(--ice);
}

.page-about .about-year__note {
  font-size: 11.5px;
  line-height: 1.4;
  opacity: .78;
}

.page-about .about-rail__note {
  margin: 12px 0 0;
  font-size: 11.5px;
  line-height: 1.6;
  color: var(--ink);
  opacity: .58;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-bottom: clamp(26px, 4vw, 46px);
  border-bottom: 1px solid var(--about-line);
}

.page-about .eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--ice);
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  max-width: 17ch;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(32px, 6vw, 62px);
  line-height: 1.14;
  letter-spacing: -.01em;
  color: var(--white);
  text-wrap: balance;
}

.page-about .about-hero__accent {
  color: var(--ice);
  box-shadow: inset 0 -.16em 0 rgba(111, 227, 225, .22);
}

.page-about .about-hero__lede {
  margin: clamp(14px, 2vw, 22px) 0 0;
  max-width: 60ch;
  font-size: clamp(15px, 1.6vw, 17.5px);
  line-height: 1.8;
  color: var(--mute);
}

.page-about .about-stats {
  margin-top: clamp(24px, 3.4vw, 40px);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  border: 1px solid var(--about-edge);
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--about-edge);
}

.page-about .about-stats .stat {
  display: flex;
  flex-direction: column;
  gap: 7px;
  padding: 16px 16px 18px;
  background: var(--night-2);
}

.page-about .about-stats .stat__value {
  font-family: var(--font-mono);
  font-size: clamp(21px, 3vw, 28px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: .03em;
  color: var(--ice);
}

.page-about .about-stats .stat__label {
  font-size: 12px;
  line-height: 1.5;
  letter-spacing: .02em;
  color: var(--mute);
}

/* ---------- 区块骨架 ---------- */
.page-about .about-section {
  padding-block: clamp(34px, 5.5vw, 68px);
  border-bottom: 1px solid var(--about-line);
}

.page-about .about-section:last-of-type {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .section-title {
  margin: 12px 0 0;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(23px, 3.3vw, 34px);
  line-height: 1.26;
  color: var(--white);
  max-width: 24ch;
  text-wrap: balance;
}

.page-about .about-section__lede {
  margin: 14px 0 0;
  max-width: 56ch;
  font-size: clamp(14px, 1.5vw, 16px);
  line-height: 1.8;
  color: var(--mute);
}

/* ---------- 通用媒体 ---------- */
.page-about .media {
  position: relative;
  margin: 0;
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--night-2);
  border: 1px solid var(--about-edge);
}

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

.page-about .media__caption {
  padding: 10px 14px 12px;
  font-size: 12px;
  line-height: 1.65;
  color: var(--mute);
  border-top: 1px solid var(--about-edge);
}

/* ---------- 品牌起点 ---------- */
.page-about .origin-grid {
  display: grid;
  gap: clamp(20px, 3vw, 34px);
  margin-top: clamp(20px, 3vw, 32px);
}

.page-about .prose p {
  margin: 0 0 1em;
  font-size: clamp(14.5px, 1.5vw, 16.5px);
  line-height: 1.85;
  color: var(--mute);
}

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

.page-about .origin-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .tag {
  display: inline-block;
  padding: 6px 13px;
  border-radius: var(--r-pill);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .04em;
  border: 1px solid transparent;
  white-space: nowrap;
}

.page-about .tag--ice {
  color: var(--ice);
  border-color: rgba(111, 227, 225, .42);
  background: rgba(111, 227, 225, .08);
}

.page-about .tag--blue {
  color: #9CC4F5;
  border-color: rgba(47, 123, 217, .48);
  background: rgba(47, 123, 217, .14);
}

.page-about .tag--yellow {
  color: var(--yellow);
  border-color: rgba(242, 193, 78, .44);
  background: rgba(242, 193, 78, .1);
}

/* ---------- 时间线 ---------- */
.page-about .timeline {
  position: relative;
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .timeline__node {
  position: relative;
  padding: 0 0 clamp(20px, 3vw, 28px) clamp(22px, 4vw, 34px);
  border-left: 1px solid var(--about-line);
  scroll-margin-top: 108px;
}

.page-about .timeline__node:last-child {
  padding-bottom: 0;
  border-left-color: transparent;
}

.page-about .timeline__node::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 8px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--night);
  border: 1px solid rgba(111, 227, 225, .55);
  transition: background .3s var(--ease), box-shadow .3s var(--ease), border-color .3s var(--ease);
}

.page-about .timeline__node:hover::before,
.page-about .timeline__node:target::before {
  background: var(--ice);
  border-color: var(--ice);
  box-shadow: 0 0 0 5px rgba(111, 227, 225, .16);
}

.page-about .timeline__year {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(25px, 3.6vw, 36px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: .05em;
  color: var(--ice);
  transition: color .3s var(--ease);
}

.page-about .timeline__node:target .timeline__year {
  color: var(--yellow);
}

.page-about .timeline__title {
  margin: 10px 0 0;
  font-family: var(--font-sans);
  font-size: 15.5px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--white);
}

.page-about .timeline__desc {
  margin: 8px 0 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--mute);
}

.page-about .timeline-figure {
  margin-top: clamp(22px, 3vw, 34px);
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  gap: clamp(20px, 3vw, 32px);
  margin-top: clamp(20px, 3vw, 30px);
}

.page-about .roles {
  display: grid;
  gap: 12px;
}

.page-about .role {
  padding: 17px 18px;
  border-radius: var(--r-lg);
  background: linear-gradient(165deg, rgba(14, 42, 70, .96), rgba(9, 30, 52, .96));
  border: 1px solid var(--about-edge);
  transition: border-color .3s var(--ease), transform .3s var(--ease), background .3s var(--ease);
}

.page-about .role:hover,
.page-about .role:focus,
.page-about .role:focus-within {
  border-color: rgba(111, 227, 225, .45);
  transform: translateY(-2px);
  outline: none;
}

.page-about .role__num {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .22em;
  color: var(--yellow);
}

.page-about .role__name {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 16.5px;
  font-weight: 700;
  color: var(--white);
}

.page-about .role__brief {
  margin: 8px 0 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--mute);
}

.page-about .role__duties {
  margin: 0;
  padding: 0;
  list-style: none;
  max-height: 0;
  overflow: hidden;
  font-size: 12.5px;
  line-height: 1.75;
  color: rgba(169, 188, 203, .92);
  transition: max-height .45s var(--ease), margin-top .45s var(--ease);
}

.page-about .role:hover .role__duties,
.page-about .role:focus .role__duties,
.page-about .role:focus-within .role__duties {
  max-height: 14rem;
  margin-top: 12px;
}

.page-about .role__duties li {
  position: relative;
  padding-left: 14px;
}

.page-about .role__duties li + li {
  margin-top: 5px;
}

.page-about .role__duties li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .82em;
  width: 7px;
  height: 1px;
  background: var(--ice);
}

/* ---------- 内容体系 ---------- */
.page-about .system-grid {
  display: grid;
  gap: clamp(14px, 2vw, 20px);
  margin-top: clamp(22px, 3vw, 34px);
}

.page-about .system-card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: clamp(18px, 2.4vw, 26px);
  border-radius: var(--r-xl);
  border: 1px solid var(--about-edge);
  background: linear-gradient(160deg, rgba(14, 42, 70, .92), rgba(7, 26, 47, .94));
}

.page-about .system-card::before {
  content: "";
  display: block;
  width: 62px;
  height: 3px;
  border-radius: var(--r-pill);
  background: linear-gradient(90deg,
    var(--blue) 0 20%,
    var(--white) 20% 40%,
    var(--red) 40% 60%,
    var(--green) 60% 80%,
    var(--yellow) 80% 100%);
}

.page-about .system-card__title {
  margin: 0;
  font-family: var(--font-sans);
  font-size: clamp(17px, 1.9vw, 20px);
  font-weight: 700;
  color: var(--white);
}

.page-about .system-card__text {
  margin: 0;
  flex: 1 1 auto;
  font-size: 13.8px;
  line-height: 1.8;
  color: var(--mute);
}

.page-about .system-card__link {
  align-self: flex-start;
  margin-top: 4px;
  font-size: 13px;
  font-weight: 600;
  color: var(--ice);
  text-decoration: none;
  border-bottom: 1px solid rgba(111, 227, 225, .4);
  padding-bottom: 2px;
  transition: border-color .25s var(--ease), color .25s var(--ease);
}

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

/* ---------- 服务原则 ---------- */
.page-about .principles {
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 1px;
  border: 1px solid var(--about-edge);
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--about-edge);
}

.page-about .principles li {
  display: grid;
  grid-template-columns: 26px minmax(0, 1fr);
  gap: 6px 12px;
  padding: 16px 18px;
  background: var(--night-2);
}

.page-about .principles__num {
  grid-row: span 2;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--ice);
  line-height: 1.5;
}

.page-about .principles strong {
  font-size: 14.5px;
  font-weight: 700;
  color: var(--white);
}

.page-about .principles li > span:last-child {
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--mute);
}

/* ---------- 联系卡片 ---------- */
.page-about .about-contact {
  margin-top: clamp(24px, 4vw, 40px);
  padding: clamp(20px, 3vw, 32px);
  border-radius: var(--r-xl);
  background: var(--paper);
  color: var(--ink);
  box-shadow: 0 18px 44px rgba(3, 12, 24, .3);
}

.page-about .about-contact__title {
  margin: 0;
  font-family: var(--font-serif);
  font-size: clamp(20px, 2.6vw, 26px);
  font-weight: 700;
  line-height: 1.4;
  color: var(--ink);
}

.page-about .about-contact__text {
  margin: 10px 0 0;
  max-width: 58ch;
  font-size: 13.8px;
  line-height: 1.8;
  color: var(--ink);
  opacity: .82;
}

.page-about .contact-list {
  margin: 20px 0 0;
  display: grid;
  gap: 14px;
}

.page-about .contact-list > div {
  padding-top: 12px;
  border-top: 1px dashed rgba(10, 26, 43, .22);
}

.page-about .contact-list dt {
  margin: 0 0 5px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--ink);
  opacity: .55;
}

.page-about .contact-list dd {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.6;
  color: var(--ink);
  word-break: break-word;
}

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

.page-about .copy-btn {
  font: inherit;
  font-size: 13.5px;
  font-weight: 600;
  padding: 11px 20px;
  border-radius: var(--r-pill);
  border: 1px solid var(--ink);
  background: transparent;
  color: var(--ink);
  cursor: pointer;
  transition: background .25s var(--ease), color .25s var(--ease), border-color .25s var(--ease);
}

.page-about .copy-btn:hover,
.page-about .copy-btn:focus-visible {
  background: var(--ink);
  color: var(--paper);
}

.page-about .copy-btn.is-copied {
  background: var(--green);
  border-color: var(--green);
  color: #04121F;
}

.page-about .about-contact__cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 22px;
  border-radius: var(--r-pill);
  background: var(--ink);
  border: 1px solid var(--ink);
  color: var(--paper);
  font-size: 13.5px;
  font-weight: 600;
  text-decoration: none;
  transition: background .25s var(--ease), color .25s var(--ease);
}

.page-about .about-contact__cta::after {
  content: "→";
  font-family: var(--font-mono);
  line-height: 1;
}

.page-about .about-contact__cta:hover,
.page-about .about-contact__cta:focus-visible {
  background: var(--blue);
  border-color: var(--blue);
  color: var(--white);
}

/* ---------- 触屏与动效偏好 ---------- */
@media (hover: none) {
  .page-about .role__duties {
    max-height: none;
    margin-top: 12px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .role,
  .page-about .role__duties,
  .page-about .timeline__node::before,
  .page-about .about-rail__years a,
  .page-about .system-card__link {
    transition: none;
  }

  .page-about .role:hover,
  .page-about .role:focus,
  .page-about .role:focus-within {
    transform: none;
  }
}

/* ---------- 平板 ---------- */
@media (min-width: 640px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

  .page-about .contact-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px 24px;
  }
}

@media (min-width: 820px) {
  .page-about .system-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: clamp(16px, 2vw, 24px);
  }

  .page-about .system-card:nth-child(even) {
    margin-top: clamp(22px, 4vw, 46px);
  }
}

/* ---------- 桌面分屏 ---------- */
@media (min-width: 900px) {
  .page-about .about-shell {
    display: grid;
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(28px, 3.6vw, 60px);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: clamp(20px, 4vh, 44px);
    z-index: 1;
    margin-bottom: 0;
    padding: 22px 18px 24px;
    border-radius: var(--r-xl);
  }

  .page-about .about-rail__years {
    flex-direction: column;
    gap: 6px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-rail__years a {
    white-space: normal;
    padding: 9px 11px;
  }

  .page-about .timeline {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: clamp(14px, 2vw, 24px);
  }

  .page-about .timeline__node {
    padding: clamp(18px, 2vw, 26px) 0 0;
    border-left: 0;
    border-top: 1px solid var(--about-line);
  }

  .page-about .timeline__node:last-child {
    border-top-color: var(--about-line);
  }

  .page-about .timeline__node::before {
    left: 0;
    top: -5px;
  }

  .page-about .timeline__node {
    scroll-margin-top: 90px;
  }
}

@media (min-width: 1000px) {
  .page-about .origin-grid {
    grid-template-columns: minmax(0, .84fr) minmax(0, 1.16fr);
    align-items: start;
  }

  .page-about .team-grid {
    grid-template-columns: minmax(0, .78fr) minmax(0, 1.22fr);
    align-items: start;
  }
}

@media (min-width: 1180px) {
  .page-about {
    --about-rail: 236px;
  }

  .page-about .about-hero h1 {
    font-size: clamp(48px, 4.6vw, 66px);
  }
}
<<<END>>>