.page-about {
  --about-rail: 168px;
  --about-gutter: clamp(20px, 3.6vw, 52px);
  --about-cut: 22px;
  background: var(--paper);
  color: var(--graphite);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-top: clamp(20px, 3vw, 34px);
  padding-bottom: clamp(34px, 5vw, 60px);
  border-bottom: 1px solid var(--line);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: -35%;
  right: -12%;
  width: 48%;
  height: 180%;
  background: linear-gradient(165deg, rgba(18, 49, 79, 0) 0%, rgba(18, 49, 79, .07) 42%, rgba(242, 107, 42, .09) 100%);
  clip-path: polygon(46% 0, 100% 0, 54% 100%, 0 100%);
  pointer-events: none;
}

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

.page-about .about-hero .eyebrow {
  margin-top: clamp(18px, 2.6vw, 30px);
  color: var(--orange);
}

.page-about .about-title {
  margin: 12px 0 0;
  max-width: 15ch;
  font-size: clamp(30px, 6.2vw, 72px);
  line-height: 1.06;
  letter-spacing: -.035em;
  font-weight: 900;
  color: var(--ink);
}

.page-about .about-title em {
  font-style: italic;
  letter-spacing: -.03em;
  color: var(--orange);
}

.page-about .about-lead {
  margin: clamp(18px, 2.4vw, 26px) 0 0;
  max-width: 58ch;
  font-size: clamp(15.5px, 1.5vw, 18px);
  line-height: 1.78;
  color: var(--graphite);
}

/* ---------- 版式骨架 ---------- */
.page-about .about-layout {
  padding-top: clamp(26px, 4vw, 52px);
  padding-bottom: clamp(44px, 7vw, 88px);
}

.page-about .about-rail {
  margin-bottom: clamp(22px, 3.5vw, 32px);
}

.page-about .rail-eyebrow {
  margin: 0 0 10px;
  color: var(--mist);
}

.page-about .rail-list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 2px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

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

.page-about .rail-link {
  display: block;
  padding: 7px 13px;
  font-size: 13px;
  line-height: 1.2;
  white-space: nowrap;
  color: var(--graphite);
  text-decoration: none;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  transition: color .2s var(--ease), border-color .2s var(--ease), background .2s var(--ease);
}

.page-about .rail-link:hover {
  border-color: var(--orange);
  color: var(--ink);
}

.page-about .rail-link[aria-current="true"] {
  background: var(--ink);
  border-color: var(--ink);
  color: var(--white);
}

/* ---------- 章节 ---------- */
.page-about .about-sec {
  padding: clamp(30px, 4.4vw, 58px) 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-sec:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .sec-side {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
}

.page-about .sec-num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--orange);
}

.page-about .sec-note {
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--mist);
}

.page-about .sec-title {
  margin: 0 0 clamp(14px, 1.8vw, 20px);
  font-size: clamp(22px, 3vw, 34px);
  line-height: 1.22;
  letter-spacing: -.02em;
  font-weight: 900;
  color: var(--ink);
}

.page-about .sec-main p {
  margin: 0 0 15px;
  max-width: 62ch;
  font-size: 15.8px;
  line-height: 1.8;
}

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

.page-about .sec-main a {
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--orange);
  padding-bottom: 1px;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.page-about .sec-main a:hover {
  color: var(--orange);
}

/* ---------- 要点列表 ---------- */
.page-about .point-list {
  display: grid;
  gap: 13px;
  margin: 20px 0 0;
  padding: 0;
  max-width: 62ch;
  list-style: none;
}

.page-about .point-list li {
  position: relative;
  padding-left: 20px;
  font-size: 15.4px;
  line-height: 1.75;
}

.page-about .point-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .78em;
  width: 10px;
  height: 2px;
  background: var(--orange);
}

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

/* ---------- 图文错位 ---------- */
.page-about .sec-split {
  display: grid;
  gap: clamp(20px, 3vw, 34px);
  align-items: start;
  margin-top: 4px;
}

.page-about .about-figure {
  margin: 0;
  min-width: 0;
}

.page-about .sec-figure {
  margin-top: clamp(20px, 2.8vw, 30px);
  max-width: 640px;
}

.page-about .about-figure-frame {
  position: relative;
  overflow: hidden;
  background: var(--space);
  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-frame img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-figure-cap {
  display: block;
  margin-top: 10px;
  padding-left: 2px;
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: .06em;
  color: var(--mist);
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  position: relative;
  display: grid;
  gap: 0;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .tl-item {
  position: relative;
  padding: 0 0 26px 26px;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 8px;
  bottom: 0;
  width: 1px;
  background: var(--line-strong);
}

.page-about .tl-item:last-child::before {
  display: none;
}

.page-about .tl-dot {
  position: absolute;
  left: 0;
  top: 4px;
  z-index: 1;
  width: 9px;
  height: 9px;
  border: 2px solid var(--orange);
  border-radius: 50%;
  background: var(--paper);
}

.page-about .tl-year {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  font-style: italic;
  font-weight: 700;
  letter-spacing: .04em;
  line-height: 1.2;
  color: var(--orange);
}

.page-about .tl-title {
  margin: 4px 0 6px;
  font-size: 16px;
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--ink);
}

.page-about .tl-text {
  margin: 0;
  max-width: 34ch;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--graphite);
}

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

/* ---------- 数据带 ---------- */
.page-about .about-stats {
  position: relative;
  overflow: hidden;
  padding: clamp(34px, 5vw, 62px) 0;
  background: var(--ink);
  color: var(--white);
}

.page-about .about-stats::before {
  content: "";
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(115deg, transparent 0 26px, rgba(185, 255, 57, .07) 26px 27px);
  pointer-events: none;
}

.page-about .about-stats .wrap {
  position: relative;
  z-index: 1;
}

.page-about .stats-title {
  margin: 0 0 clamp(20px, 3vw, 32px);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: .2em;
  color: rgba(255, 255, 255, .55);
}

.page-about .stat-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(20px, 3vw, 34px);
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(28px, 4vw, 44px);
  font-style: italic;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--neon);
}

.page-about .stat-label {
  display: block;
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.5;
  letter-spacing: .04em;
  color: rgba(255, 255, 255, .7);
}

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

@media (min-width: 760px) {
  .page-about .about-sec {
    display: grid;
    grid-template-columns: 106px minmax(0, 1fr);
    column-gap: clamp(16px, 2.4vw, 32px);
  }

  .page-about .sec-side {
    display: block;
    align-self: start;
    margin-bottom: 0;
    padding-top: 7px;
    padding-left: 12px;
    border-left: 2px solid var(--orange);
  }

  .page-about .sec-num,
  .page-about .sec-note {
    display: block;
  }

  .page-about .sec-note {
    margin-top: 7px;
  }
}

@media (min-width: 820px) {
  .page-about .about-timeline {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    margin-top: 34px;
  }

  .page-about .about-timeline::before {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    top: 36px;
    height: 1px;
    background: var(--line-strong);
  }

  .page-about .tl-item {
    padding: 0 18px 0 0;
  }

  .page-about .tl-item::before {
    display: none;
  }

  .page-about .tl-dot {
    position: relative;
    top: auto;
    left: auto;
    z-index: 1;
    display: block;
    margin: 14px 0 0;
  }

  .page-about .tl-title {
    margin: 18px 0 6px;
  }
}

/* ---------- 桌面框架式侧栏 ---------- */
@media (min-width: 960px) {
  .page-about .about-layout {
    display: grid;
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 26px);
    align-self: start;
    margin-bottom: 0;
    padding-right: 18px;
  }

  .page-about .rail-eyebrow {
    padding-left: 2px;
  }

  .page-about .rail-list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .rail-link {
    padding: 10px 0 10px 14px;
    font-size: 13.5px;
    white-space: normal;
    border: 0;
    border-left: 2px solid transparent;
    border-radius: 0;
  }

  .page-about .rail-link[aria-current="true"] {
    background: rgba(242, 107, 42, .09);
    border-left-color: var(--orange);
    color: var(--ink);
    font-weight: 700;
  }

  .page-about .about-body {
    min-width: 0;
    padding-left: var(--about-gutter);
    border-left: 1px solid var(--line);
  }
}

@media (min-width: 1024px) {
  .page-about .sec-split {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, .88fr);
    gap: clamp(22px, 3vw, 40px);
  }
}
<<<END>>>