.page-about {
  --about-rail: 200px;
  --about-cut: 18px;
  display: block;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(24px, 4vw, 52px) 0 clamp(30px, 5vw, 56px);
  border-bottom: 1px solid var(--line);
  background-image: repeating-linear-gradient(
    115deg,
    transparent 0 48px,
    rgba(78, 242, 195, 0.055) 48px 49px
  );
}

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

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(20px, 3vw, 40px);
  margin-top: clamp(16px, 2.4vw, 26px);
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(34px, 5.4vw, 66px);
  line-height: 1.03;
  letter-spacing: -0.015em;
  color: var(--warm);
  margin: 12px 0 16px;
  max-width: 15em;
}

.page-about .about-hero .lede {
  font-size: clamp(15.5px, 1.6vw, 18px);
  line-height: 1.78;
  color: var(--muted);
  max-width: 46ch;
  margin: 0 0 22px;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-hero__media {
  margin: 0;
  padding: 9px;
  background: var(--board);
  border: 1px solid var(--line);
}

.page-about .about-hero__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.page-about .about-hero__media figcaption {
  padding: 10px 2px 1px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.page-about .about-hero__stats {
  display: grid;
  gap: 1px;
  margin: clamp(22px, 4vw, 38px) 0 0;
  padding: 0;
  list-style: none;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-hero__stats li {
  background: var(--night);
  padding: 15px 16px;
}

.page-about .about-stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(23px, 3vw, 30px);
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-stat__key {
  display: block;
  margin-top: 7px;
  font-size: 12.5px;
  line-height: 1.55;
  color: var(--muted);
}

/* ---------- 主体骨架 ---------- */
.page-about .about-body {
  display: grid;
  gap: 0;
  padding-top: clamp(20px, 3vw, 40px);
  padding-bottom: clamp(40px, 6vw, 72px);
}

.page-about .about-rail {
  position: sticky;
  top: 0;
  z-index: 6;
  background: var(--night);
  border-bottom: 1px solid var(--line);
  padding: 10px 0 8px;
  margin-bottom: 6px;
}

.page-about .about-rail__title {
  margin: 0 0 7px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--muted);
}

.page-about .about-rail__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 3px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
}

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

.page-about .about-rail__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 40px;
  padding: 8px 12px;
  font-size: 13.5px;
  color: var(--muted);
  text-decoration: none;
  white-space: nowrap;
  border: 1px solid var(--line);
  transition: color 160ms ease, background-color 160ms ease, border-color 160ms ease;
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--warm);
  border-color: var(--cyan);
  background: rgba(78, 242, 195, 0.08);
  outline: none;
}

.page-about .about-rail__num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--cyan);
}

.page-about .about-flow {
  display: grid;
  gap: clamp(18px, 2.6vw, 30px);
  padding-top: clamp(18px, 3vw, 30px);
}

/* ---------- 章节画板 ---------- */
.page-about .about-chapter {
  position: relative;
  padding: clamp(20px, 3vw, 34px);
  background: var(--board);
  box-shadow: inset 0 0 0 1px var(--line);
  clip-path: polygon(
    0 0,
    calc(100% - var(--about-cut)) 0,
    100% var(--about-cut),
    100% 100%,
    var(--about-cut) 100%,
    0 calc(100% - var(--about-cut))
  );
  scroll-margin-top: 92px;
}

.page-about .about-chapter__head {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 14px;
}

.page-about .about-chapter__num {
  flex: 0 0 auto;
  padding: 3px 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--night);
  background: var(--cyan);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 6px 100%, 0 calc(100% - 6px));
}

.page-about .about-chapter h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(22px, 3vw, 34px);
  line-height: 1.14;
  letter-spacing: -0.01em;
  color: var(--warm);
}

.page-about .about-chapter > p {
  margin: 0 0 14px;
  max-width: 66ch;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-chapter > p:last-child {
  margin-bottom: 0;
}

.page-about .about-chapter a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(78, 242, 195, 0.45);
  transition: color 160ms ease, border-color 160ms ease;
}

.page-about .about-chapter a:hover,
.page-about .about-chapter a:focus-visible {
  color: var(--warm);
  border-bottom-color: var(--warm);
  outline: none;
}

/* ---------- 01 起步 ---------- */
.page-about .about-steps {
  display: grid;
  gap: 20px;
  margin: 20px 0 0;
  padding: 0 0 0 18px;
  list-style: none;
  border-left: 1px solid var(--line);
}

.page-about .about-step {
  position: relative;
}

.page-about .about-step::before {
  content: "";
  position: absolute;
  left: -24px;
  top: 6px;
  width: 9px;
  height: 9px;
  background: var(--night);
  border: 2px solid var(--cyan);
  transform: rotate(45deg);
}

.page-about .about-step__year {
  display: block;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.1em;
  color: var(--orange);
}

.page-about .about-step h3 {
  margin: 3px 0 5px;
  font-family: var(--font-display);
  font-size: 19px;
  line-height: 1.2;
  color: var(--warm);
}

.page-about .about-step p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 02 生产流程 ---------- */
.page-about .about-craft {
  display: grid;
  gap: 10px;
  margin: 20px 0 18px;
  padding: 0;
  list-style: none;
}

.page-about .about-craft li {
  padding: 14px 16px;
  background: var(--night);
  border-left: 2px solid var(--line);
  transition: border-color 160ms ease, background-color 160ms ease;
}

.page-about .about-craft li:hover,
.page-about .about-craft li:focus-within {
  border-left-color: var(--cyan);
  background: rgba(78, 242, 195, 0.06);
}

.page-about .about-craft h3 {
  margin: 0 0 4px;
  font-family: var(--font-display);
  font-size: 17px;
  line-height: 1.2;
  color: var(--warm);
}

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

.page-about .about-rhythm {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 14px;
}

/* ---------- 03 版本时间轴 ---------- */
.page-about .about-timeline {
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .tl-item {
  position: relative;
  padding: 0 0 22px 26px;
  border-left: 2px solid var(--line);
}

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

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -8px;
  top: 3px;
  width: 12px;
  height: 12px;
  background: var(--board);
  border: 2px solid var(--cyan);
  transform: rotate(45deg);
  transition: background-color 160ms ease, border-color 160ms ease;
}

.page-about .tl-item:hover::before,
.page-about .tl-item:focus-within::before {
  background: var(--cyan);
}

.page-about .tl-item--now::before {
  background: var(--orange);
  border-color: var(--orange);
}

.page-about .tl-item__ver {
  display: block;
  margin-bottom: 3px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--cyan);
}

.page-about .tl-item--now .tl-item__ver {
  color: var(--orange);
}

.page-about .tl-item h3 {
  margin: 0 0 4px;
  font-family: var(--font-display);
  font-size: 18.5px;
  line-height: 1.2;
  color: var(--warm);
}

.page-about .tl-item__brief {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .tl-item__more {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 180ms ease;
}

.page-about .tl-item__more > p {
  overflow: hidden;
  margin: 0;
  padding-top: 7px;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--pale);
  border-top: 1px dashed transparent;
  transition: border-color 180ms ease;
}

.page-about .tl-item:hover .tl-item__more,
.page-about .tl-item:focus-within .tl-item__more {
  grid-template-rows: 1fr;
}

.page-about .tl-item:hover .tl-item__more > p,
.page-about .tl-item:focus-within .tl-item__more > p {
  border-top-color: var(--line);
}

/* ---------- 图片块 ---------- */
.page-about .about-shot {
  margin: 20px 0;
  padding: 8px;
  background: var(--night);
  border: 1px solid var(--line);
}

.page-about .about-shot img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .about-shot figcaption {
  padding: 9px 4px 2px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: 0.03em;
  color: var(--muted);
}

/* ---------- 04 团队 ---------- */
.page-about .about-team {
  display: grid;
  gap: 20px;
  margin-top: 18px;
}

.page-about .about-bars {
  display: grid;
  gap: 16px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-bar {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 5px 12px;
  align-items: baseline;
}

.page-about .about-bar__label {
  font-size: 14.5px;
  color: var(--warm);
}

.page-about .about-bar__num {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--cyan);
}

.page-about .about-bar__track {
  grid-column: 1 / -1;
  display: block;
  height: 6px;
  background: var(--line);
  overflow: hidden;
}

.page-about .about-bar__fill {
  display: block;
  height: 100%;
  background: var(--cyan);
  transition: background-color 160ms ease;
}

.page-about .about-bar:nth-child(1) .about-bar__fill { width: 34.6%; }
.page-about .about-bar:nth-child(2) .about-bar__fill { width: 30.8%; }
.page-about .about-bar:nth-child(3) .about-bar__fill { width: 19.2%; }
.page-about .about-bar:nth-child(4) .about-bar__fill { width: 15.4%; background: var(--orange); }

.page-about .about-bar__note {
  grid-column: 1 / -1;
  font-size: 12.5px;
  line-height: 1.65;
  color: var(--muted);
  opacity: 0.55;
  transition: opacity 160ms ease, color 160ms ease;
}

.page-about .about-bar:hover .about-bar__note,
.page-about .about-bar:focus-within .about-bar__note {
  opacity: 1;
  color: var(--pale);
}

.page-about .about-facts {
  margin: 0;
  padding: 16px 18px;
  background: var(--night);
  box-shadow: inset 0 0 0 1px var(--line);
}

.page-about .about-facts__row {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 9px 0;
  border-bottom: 1px dashed rgba(30, 74, 61, 0.9);
}

.page-about .about-facts__row:first-child { padding-top: 0; }
.page-about .about-facts__row:last-child {
  padding-bottom: 0;
  border-bottom: 0;
}

.page-about .about-facts dt {
  flex: 0 0 auto;
  font-size: 13px;
  color: var(--muted);
}

.page-about .about-facts dd {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--warm);
  text-align: right;
}

/* ---------- 05 归档 ---------- */
.page-about .about-metrics {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 18px 0;
  padding: 0;
  list-style: none;
  background: var(--line);
  box-shadow: inset 0 0 0 1px var(--line);
}

.page-about .about-metrics li {
  padding: 14px;
  background: var(--night);
}

.page-about .about-metrics__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(20px, 2.6vw, 27px);
  line-height: 1.1;
  color: var(--orange);
}

.page-about .about-metrics__key {
  display: block;
  margin-top: 5px;
  font-size: 12.5px;
  line-height: 1.5;
  color: var(--muted);
}

.page-about .about-filters {
  margin: 20px 0;
  padding-top: 16px;
  border-top: 1px dashed var(--line);
}

.page-about .about-filters__title {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--muted);
}

.page-about .about-filters__list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-filters__list li {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 10px 12px;
  font-size: 14.5px;
  color: var(--warm);
  background: var(--night);
  border-left: 2px solid var(--line);
  transition: border-color 160ms ease, color 160ms ease;
}

.page-about .about-filters__list li:hover {
  border-left-color: var(--cyan);
  color: var(--cyan);
}

.page-about .about-filters__num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--cyan);
}

/* ---------- 06 合作 ---------- */
.page-about .about-partners {
  display: grid;
  gap: 12px;
  margin: 18px 0;
}

.page-about .about-partner {
  padding: 18px;
  background: var(--night);
  box-shadow: inset 0 0 0 1px var(--line);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 12px), calc(100% - 12px) 100%, 0 100%);
  transition: box-shadow 160ms ease;
}

.page-about .about-partner:hover {
  box-shadow: inset 0 0 0 1px var(--cyan);
}

.page-about .about-partner__num {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 30px;
  line-height: 1;
  color: var(--orange);
}

.page-about .about-partner h3 {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 18px;
  line-height: 1.2;
  color: var(--warm);
}

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

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  padding: clamp(22px, 4vw, 42px);
  background: linear-gradient(135deg, rgba(255, 138, 61, 0.16), rgba(78, 242, 195, 0.08));
  box-shadow: inset 0 0 0 1px var(--line);
  clip-path: polygon(
    0 0,
    calc(100% - 26px) 0,
    100% 26px,
    100% 100%,
    26px 100%,
    0 calc(100% - 26px)
  );
}

.page-about .about-cta__eyebrow {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: var(--orange);
}

.page-about .about-cta h2 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(22px, 3vw, 34px);
  line-height: 1.14;
  letter-spacing: -0.01em;
  color: var(--warm);
}

.page-about .about-cta p {
  margin: 0 0 18px;
  max-width: 60ch;
  font-size: 15px;
  line-height: 1.78;
  color: var(--pale);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .about-craft {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

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

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

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

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    align-items: end;
  }

  .page-about .about-body {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(28px, 4vw, 56px);
    align-items: start;
  }

  .page-about .about-rail {
    top: 24px;
    z-index: 2;
    margin-bottom: 0;
    padding: 4px 0 0;
    border-bottom: 0;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    gap: 2px;
    overflow: visible;
    padding: 0;
  }

  .page-about .about-rail__link {
    display: flex;
    width: 100%;
    padding: 10px 12px;
    border: 0;
    border-left: 2px solid var(--line);
    background: transparent;
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    border-left-color: var(--cyan);
    background: rgba(78, 242, 195, 0.06);
  }

  .page-about .about-flow {
    padding-top: 0;
  }

  .page-about .about-chapter {
    scroll-margin-top: 40px;
  }

  .page-about .about-team {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    align-items: start;
    gap: clamp(24px, 3vw, 36px);
  }
}

@media (hover: none) {
  .page-about .tl-item__more {
    grid-template-rows: 1fr;
  }

  .page-about .tl-item__more > p {
    border-top-color: var(--line);
  }

  .page-about .about-bar__note {
    opacity: 0.85;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .about-craft li,
  .page-about .about-bar__fill,
  .page-about .about-bar__note,
  .page-about .about-filters__list li,
  .page-about .tl-item::before,
  .page-about .tl-item__more,
  .page-about .tl-item__more > p,
  .page-about .about-partner,
  .page-about .about-chapter a {
    transition: none;
  }
}
<<<END>>>