.page-about {
  --about-amber-ink: #8a5a08;
  --about-ink-soft: rgba(20, 17, 12, .68);
  --about-line: 1px solid var(--hairline);
  background: var(--ink);
  color: var(--paper);
  font-family: var(--font-body);
  padding-bottom: 72px;
}

.page-about a:focus-visible,
.page-about button:focus-visible,
.page-about .tl__item:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 6px;
}

.page-about .eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--cyan);
}

/* ---------- 面包屑 ---------- */
.page-about .crumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: 28px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .crumb a {
  color: var(--mist);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

.page-about .crumb a:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.page-about .crumb__sep {
  color: var(--hairline);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-top: 24px;
}

.page-about .about-hero__grid {
  display: grid;
  gap: 28px;
}

.page-about .about-hero__title {
  margin: 14px 0 18px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(40px, 11vw, 96px);
  line-height: .94;
  letter-spacing: -.02em;
}

.page-about .about-hero__lede {
  max-width: 46ch;
  margin: 0;
  color: var(--mist);
  font-size: 16px;
  line-height: 1.8;
}

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

.page-about .about-hero__fig {
  margin: 0;
}

/* ---------- 图片容器 ---------- */
.page-about .media-frame {
  position: relative;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border-radius: var(--r-lg);
  border: var(--about-line);
  background: var(--slate);
}

.page-about .media-frame--tall {
  aspect-ratio: 4 / 5;
}

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

.page-about .media-frame__cap {
  display: block;
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--mist);
}

/* ---------- 章节标题 ---------- */
.page-about .about-head {
  max-width: 720px;
  margin-bottom: 28px;
}

.page-about .about-head__title {
  margin: 12px 0 12px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(28px, 5.4vw, 44px);
  line-height: 1.06;
  letter-spacing: -.01em;
}

.page-about .about-head__text {
  margin: 0;
  color: var(--mist);
  font-size: 16px;
  line-height: 1.75;
}

/* ---------- 能力三卡 ---------- */
.page-about .about-cards {
  display: grid;
  gap: 14px;
}

.page-about .about-card {
  position: relative;
  padding: 24px 22px 26px;
  border: var(--about-line);
  border-radius: var(--r-xl);
  background: var(--panel);
  overflow: hidden;
}

.page-about .about-card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: var(--cyan);
}

.page-about .about-card:nth-child(2) {
  background: var(--slate);
}

.page-about .about-card:nth-child(2)::before {
  background: var(--amber);
}

.page-about .about-card:nth-child(3)::before {
  background: var(--orange);
}

.page-about .about-card__tag {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--amber);
  text-transform: uppercase;
}

.page-about .about-card__title {
  margin: 10px 0 10px;
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 800;
  line-height: 1.2;
}

.page-about .about-card p {
  margin: 0;
  color: var(--mist);
  font-size: 14px;
  line-height: 1.75;
}

/* ---------- 数字条 ---------- */
.page-about .about-stats {
  list-style: none;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1px;
  margin: 26px 0 0;
  padding: 0;
  background: var(--hairline);
  border-radius: var(--r-lg);
  overflow: hidden;
}

.page-about .about-stats .stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 18px 16px;
  background: var(--ink);
}

.page-about .about-stats .stat__num {
  font-family: var(--font-mono);
  font-size: clamp(24px, 6vw, 38px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--amber);
}

.page-about .about-stats .stat__label {
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--mist);
}

/* ---------- 时间轴 ---------- */
.page-about .tl {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 34px;
}

.page-about .tl::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--cyan), var(--hairline) 72%, transparent);
}

.page-about .tl__item {
  position: relative;
  margin-bottom: 16px;
}

.page-about .tl__item::before {
  content: "";
  position: absolute;
  left: -31px;
  top: 20px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--amber);
  box-shadow: 0 0 0 4px var(--ink), 0 0 0 5px var(--hairline);
}

.page-about .tl__item:last-child::before {
  background: var(--cyan);
}

.page-about .tl__card {
  padding: 20px 20px 22px;
  border: var(--about-line);
  border-radius: var(--r-xl);
  background: var(--panel);
  transition: transform .4s var(--ease), border-color .3s var(--ease), background .3s var(--ease);
}

.page-about .tl__item:last-child .tl__card {
  background: linear-gradient(140deg, var(--slate), var(--panel));
  border-color: rgba(59, 240, 206, .45);
}

.page-about .tl__item:hover .tl__card,
.page-about .tl__item:focus-within .tl__card {
  transform: translateY(-4px);
  border-color: var(--cyan);
  background: var(--slate);
}

.page-about .tl__year {
  display: block;
  margin-bottom: 6px;
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--amber);
}

.page-about .tl__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 800;
  line-height: 1.2;
}

.page-about .tl__base {
  margin: 0;
  color: var(--mist);
  font-size: 14px;
  line-height: 1.75;
}

.page-about .tl__more {
  margin: 10px 0 0;
  overflow: hidden;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.7;
  color: var(--cyan);
  transition: max-height .35s var(--ease), opacity .3s var(--ease), margin .3s var(--ease);
}

/* ---------- 纸白反转区 ---------- */
.page-about .about-paper {
  padding: 26px 20px 30px;
  border-radius: var(--r-xl);
  background-color: var(--paper);
  color: var(--paper-ink);
  box-shadow: var(--shadow-panel);
  background-image:
    linear-gradient(to right, rgba(20, 17, 12, .055) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(20, 17, 12, .055) 1px, transparent 1px);
  background-size: 30px 30px;
  overflow: hidden;
}

.page-about .about-paper__grid {
  display: grid;
  gap: 22px;
}

.page-about .about-paper__grid + .about-paper__grid {
  margin-top: 34px;
  padding-top: 30px;
  border-top: 1px dashed rgba(20, 17, 12, .3);
}

.page-about .about-paper__fig {
  margin: 0;
}

.page-about .about-paper .media-frame {
  border-color: rgba(20, 17, 12, .22);
  background: #d9d2c2;
}

.page-about .about-paper .media-frame__cap {
  color: var(--about-ink-soft);
}

.page-about .about-paper .about-paper__num {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--about-amber-ink);
}

.page-about .about-paper__title {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-size: clamp(24px, 5.2vw, 34px);
  font-weight: 900;
  line-height: 1.06;
  letter-spacing: -.01em;
  color: var(--paper-ink);
}

.page-about .about-paper__body p {
  margin: 0 0 12px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--about-ink-soft);
}

.page-about .about-paper .about-steps {
  list-style: none;
  display: grid;
  gap: 12px;
  margin: 18px 0 16px;
  padding: 0;
}

.page-about .about-paper .about-steps li {
  padding-left: 14px;
  border-left: 2px solid rgba(20, 17, 12, .18);
  font-size: 14px;
  line-height: 1.75;
  color: var(--about-ink-soft);
}

.page-about .about-steps__t {
  display: block;
  margin-bottom: 2px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .08em;
  color: var(--paper-ink);
}

.page-about .about-paper .about-paper__aside {
  margin: 0;
  padding: 12px 14px;
  border-radius: var(--r-md);
  background: rgba(20, 17, 12, .06);
  font-size: 13px;
  line-height: 1.75;
  color: var(--paper-ink);
}

.page-about .about-paper .about-team {
  list-style: none;
  display: grid;
  gap: 14px;
  margin: 18px 0 14px;
  padding: 0;
}

.page-about .about-paper .about-team li {
  display: grid;
  grid-template-columns: auto 1fr;
  grid-template-areas:
    "num label"
    "num desc";
  column-gap: 14px;
  align-items: baseline;
  padding-bottom: 12px;
  border-bottom: 1px solid rgba(20, 17, 12, .14);
}

.page-about .about-team__num {
  grid-area: num;
  font-family: var(--font-mono);
  font-size: 34px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--paper-ink);
}

.page-about .about-team__label {
  grid-area: label;
  font-size: 15px;
  font-weight: 700;
  color: var(--paper-ink);
}

.page-about .about-paper .about-team li p {
  grid-area: desc;
  margin: 3px 0 0;
  font-size: 13px;
  line-height: 1.65;
  color: var(--about-ink-soft);
}

.page-about .about-paper .about-team__note {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.8;
  color: var(--about-amber-ink);
}

/* ---------- 合作生态 ---------- */
.page-about .about-eco__acc {
  display: grid;
  gap: 12px;
}

.page-about .about-eco__acc .accordion__item {
  background: var(--panel);
  border: var(--about-line);
  border-radius: var(--r-lg);
  overflow: hidden;
}

.page-about .about-eco__h {
  margin: 0;
  font-size: inherit;
  font-weight: inherit;
}

.page-about .accordion__trigger {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 14px;
  width: 100%;
  padding: 20px;
  border: 0;
  background: none;
  color: var(--paper);
  font-family: inherit;
  text-align: left;
  cursor: pointer;
  transition: background .25s var(--ease);
}

.page-about .accordion__trigger:hover {
  background: var(--slate);
}

.page-about .about-eco__num {
  font-family: var(--font-mono);
  font-size: clamp(30px, 8vw, 48px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--amber);
}

.page-about .about-eco__num--sm {
  font-size: clamp(20px, 5vw, 28px);
}

.page-about .about-eco__label {
  flex: 1 1 150px;
  min-width: 0;
  font-size: 15px;
  font-weight: 600;
  line-height: 1.45;
}

.page-about .about-eco__hint {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .accordion__panel-inner {
  padding: 0 20px 20px;
  color: var(--mist);
  font-size: 14px;
  line-height: 1.8;
}

.page-about .accordion__panel-inner p {
  margin: 0 0 10px;
}

.page-about .accordion__panel-inner p:last-child {
  margin-bottom: 0;
}

.page-about .about-eco__tools {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px;
  margin-top: 20px;
}

.page-about .about-eco__link {
  color: var(--cyan);
  font-size: 14px;
  text-decoration: none;
  border-bottom: 1px solid rgba(59, 240, 206, .45);
}

.page-about .about-eco__link:hover {
  border-bottom-color: var(--cyan);
}

/* ---------- 服务范围胶囊 ---------- */
.page-about .about-scope__title {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(26px, 5.6vw, 40px);
  line-height: 1.08;
  letter-spacing: -.01em;
}

.page-about .about-scope__text {
  max-width: 56ch;
  margin: 0;
  color: var(--mist);
  font-size: 15px;
  line-height: 1.8;
}

.page-about .about-caps {
  display: grid;
  gap: 12px;
  margin-top: 24px;
}

.page-about .about-cap {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 22px 26px;
  border-radius: var(--r-pill);
  border: 1px solid var(--hairline);
  background: var(--panel);
  color: var(--paper);
  text-decoration: none;
  transition: transform .3s var(--ease), background .3s var(--ease), border-color .3s var(--ease);
}

.page-about .about-cap:hover {
  transform: translateY(-3px);
  background: var(--slate);
}

.page-about .about-cap__k {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .about-cap__t {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.45;
}

.page-about .about-cap--cyan {
  border-color: rgba(59, 240, 206, .5);
}

.page-about .about-cap--cyan .about-cap__k {
  color: var(--cyan);
}

.page-about .about-cap--amber {
  border-color: rgba(245, 185, 74, .48);
}

.page-about .about-cap--amber .about-cap__k {
  color: var(--amber);
}

.page-about .about-cap--orange {
  border-color: rgba(255, 107, 53, .52);
}

.page-about .about-cap--orange .about-cap__k {
  color: var(--orange);
}

.page-about .about-scope__foot {
  margin: 22px 0 0;
  font-size: 13px;
  color: var(--mist);
}

.page-about .about-scope__foot a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(59, 240, 206, .45);
}

/* ---------- 平板 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    align-items: end;
    gap: 32px;
  }

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

  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

  .page-about .about-paper .about-team li {
    grid-template-areas:
      "num"
      "label"
      "desc";
    grid-template-columns: minmax(0, 1fr);
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .page-about {
    padding-bottom: 104px;
  }

  .page-about .about-head {
    margin-bottom: 42px;
  }

  .page-about .about-paper {
    padding: 48px 44px 52px;
  }

  .page-about .about-paper__grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
    gap: 40px;
    align-items: start;
  }

  .page-about .about-paper__grid--alt {
    grid-template-columns: minmax(0, 6fr) minmax(0, 5fr);
    align-items: start;
  }

  .page-about .about-paper__fig--right {
    margin-right: -64px;
    margin-top: -12px;
  }

  /* 时间轴错位排版 */
  .page-about .tl {
    padding-left: 0;
    padding-top: 4px;
  }

  .page-about .tl::before {
    left: 118px;
  }

  .page-about .tl__item {
    display: grid;
    grid-template-columns: 100px minmax(0, 1fr);
    gap: 40px;
    align-items: start;
    margin-bottom: 22px;
  }

  .page-about .tl__item::before {
    left: 112px;
    top: 32px;
  }

  .page-about .tl__year {
    margin: 0;
    padding-top: 22px;
    font-size: 30px;
    text-align: right;
  }

  .page-about .tl__card {
    padding: 24px 26px 26px;
  }

  .page-about .tl__item:nth-child(even) .tl__card {
    margin-left: 32px;
  }

  /* 悬停/聚焦展开一句话说明 */
  .page-about .tl__more {
    max-height: 0;
    margin-top: 0;
    opacity: 0;
  }

  .page-about .tl__item:hover .tl__more,
  .page-about .tl__item:focus-within .tl__more {
    max-height: 140px;
    margin-top: 10px;
    opacity: 1;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tl__card,
  .page-about .about-cap,
  .page-about .tl__more,
  .page-about .accordion__trigger {
    transition: none;
  }

  .page-about .tl__item:hover .tl__card,
  .page-about .tl__item:focus-within .tl__card,
  .page-about .about-cap:hover {
    transform: none;
  }
}
<<<END>>>