.page-about {
  --about-rail: 30px;
  display: block;
  background: var(--ink);
  color: var(--paper);
}

/* ---------- 面包屑上下文 ---------- */
.page-about .breadcrumbs {
  margin: 20px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: 34px 0 30px;
  border-bottom: 1px solid var(--line);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: -60px;
  right: -70px;
  width: 280px;
  height: 280px;
  background: linear-gradient(150deg, rgba(201, 162, 75, 0.18), rgba(192, 52, 43, 0.06) 55%, transparent 74%);
  clip-path: polygon(32% 0, 100% 0, 100% 100%, 0 100%);
  pointer-events: none;
}

.page-about .about-hero__kicker {
  position: relative;
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--gold);
}

.page-about .about-hero__title {
  position: relative;
  margin: 0 0 18px;
  max-width: 18em;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(28px, 6.4vw, 52px);
  line-height: 1.16;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .about-hero__lede {
  position: relative;
  margin: 0;
  max-width: 66ch;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(237, 231, 218, 0.82);
}

.page-about .about-facts {
  list-style: none;
  margin: 28px 0 0;
  padding: 1px;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-facts li {
  display: flex;
  flex-direction: column;
  gap: 7px;
  padding: 14px 16px;
  background: var(--deep);
}

.page-about .about-facts__k {
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--jade);
}

.page-about .about-facts__v {
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--gold);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-sec {
  padding: 46px 0;
  border-bottom: 1px solid var(--line);
  scroll-margin-top: 92px;
}

.page-about .about-sec__head {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 26px;
}

.page-about .section-number {
  flex: none;
  font-family: var(--font-mono);
  font-size: clamp(24px, 5.6vw, 38px);
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--gold);
}

.page-about .about-sec__titles {
  min-width: 0;
}

.page-about .about-sec__titles h2 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(20px, 3.6vw, 28px);
  line-height: 1.25;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .about-sec p {
  margin: 0 0 14px;
  font-size: 15px;
  line-height: 1.82;
  color: rgba(237, 231, 218, 0.82);
}

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

.page-about .about-sec .about-sec__sub {
  margin: 0;
  max-width: 64ch;
  font-size: 14px;
  line-height: 1.78;
  color: var(--jade);
}

.page-about .about-sec .num {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-about .about-sec a {
  color: var(--gold);
  text-decoration: none;
  border-bottom: 1px solid rgba(201, 162, 75, 0.35);
}

.page-about .about-sec a:hover,
.page-about .about-sec a:focus-visible {
  color: var(--gold-hi);
  border-bottom-color: var(--gold-hi);
}

/* ---------- 01 时间线 ---------- */
.page-about .about-timeline-wrap {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
}

.page-about .about-timeline__media {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--deep);
}

.page-about .about-timeline__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.page-about .about-timeline__media figcaption {
  padding: 10px 12px;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  line-height: 1.6;
  color: var(--jade);
}

.page-about .stage-ticks {
  list-style: none;
  margin: 0 0 24px;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .stage-ticks a {
  display: inline-block;
  padding: 5px 12px;
  border: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--jade);
  text-decoration: none;
  transition: background 160ms ease, color 160ms ease, border-color 160ms ease;
}

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

.page-about .timeline {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 var(--about-rail);
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 6px;
  bottom: 6px;
  width: 1px;
  background: var(--line);
}

.page-about .timeline__item {
  position: relative;
  padding: 0 0 34px;
  opacity: 0.4;
  transition: opacity 420ms ease;
}

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

.page-about .timeline__item.is-visible {
  opacity: 1;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 6px;
  width: 11px;
  height: 11px;
  background: var(--ink);
  border: 1px solid var(--gold);
  transition: background 320ms ease;
}

.page-about .timeline__item.is-visible::before {
  background: var(--gold);
}

.page-about .timeline__year {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.16em;
  color: var(--gold);
}

.page-about .timeline__item h3 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 18px;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .about-sec .timeline__meta {
  margin: 0 0 8px;
  font-size: 13px;
  line-height: 1.72;
  color: var(--jade);
}

.page-about .about-sec .timeline__meta span {
  display: inline-block;
  margin-right: 8px;
  padding-bottom: 1px;
  border-bottom: 1px solid rgba(201, 162, 75, 0.32);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--gold);
}

/* ---------- 02 分工 ---------- */
.page-about .crew-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .crew {
  padding: 24px 20px;
  background: var(--deep);
}

.page-about .crew__idx {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--gold);
}

.page-about .crew h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 19px;
  color: var(--paper);
}

.page-about .about-sec .crew__count {
  margin: 0 0 12px;
  font-size: 13px;
  color: var(--jade);
}

.page-about .about-sec .crew__count .num {
  font-size: 26px;
  letter-spacing: 0.04em;
  color: var(--gold);
}

.page-about .about-sec .crew__desc {
  margin: 0 0 14px;
  font-size: 14px;
  line-height: 1.78;
  color: rgba(237, 231, 218, 0.78);
}

.page-about .crew__list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .crew__list li {
  position: relative;
  padding: 9px 0 9px 16px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--jade);
  border-bottom: 1px solid rgba(46, 82, 69, 0.5);
}

.page-about .crew__list li:last-child {
  border-bottom: 0;
}

.page-about .crew__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 16px;
  width: 7px;
  height: 1px;
  background: var(--gold);
}

.page-about .about-workbench {
  margin: 26px 0 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  border: 1px solid var(--line);
  background: var(--panel);
}

.page-about .about-workbench img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 10 / 7;
  object-fit: cover;
}

.page-about .about-workbench figcaption {
  padding: 20px;
}

.page-about .about-workbench__label {
  display: inline-block;
  margin-bottom: 10px;
  padding: 3px 9px;
  border: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--gold);
}

.page-about .about-workbench figcaption p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: rgba(237, 231, 218, 0.8);
}

/* ---------- 03 校准 ---------- */
.page-about .cal-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  margin-bottom: 24px;
}

.page-about .cal-card {
  padding: 22px 20px;
  background: var(--deep);
}

.page-about .about-sec .cal-card__time {
  display: block;
  margin-bottom: 10px;
  font-size: 24px;
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-about .cal-card h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 17px;
  color: var(--paper);
}

.page-about .about-sec .cal-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--jade);
}

.page-about .cal-flow {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .cal-flow li {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
  font-size: 14px;
  line-height: 1.7;
  color: rgba(237, 231, 218, 0.82);
}

.page-about .about-sec .cal-flow .num {
  flex: none;
  min-width: 68px;
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--gold);
}

.page-about .about-sec .cal-note {
  padding-left: 14px;
  border-left: 2px solid var(--gold);
  font-size: 13px;
  line-height: 1.85;
  color: var(--jade);
}

/* ---------- 04 编号 ---------- */
.page-about .codes-wrap {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
}

.page-about .code-view {
  margin-top: 20px;
  padding-top: 22px;
  border-top: 1px solid var(--line);
}

.page-about .code-view:first-of-type {
  margin-top: 18px;
}

.page-about .code-view h3 {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 18px;
  color: var(--paper);
}

.page-about .code-view p {
  font-size: 14px;
  line-height: 1.8;
}

.page-about .code-svg {
  display: block;
  width: 100%;
  max-width: 460px;
  height: auto;
  margin: 0 0 18px;
}

.page-about .code-svg .box {
  fill: rgba(18, 41, 31, 0.9);
  stroke: var(--line);
  stroke-width: 1;
}

.page-about .code-svg .box--hi {
  fill: rgba(201, 162, 75, 0.08);
  stroke: var(--gold);
}

.page-about .code-svg .val {
  font-family: var(--font-mono);
  font-size: 26px;
  letter-spacing: 0.08em;
  fill: var(--gold);
}

.page-about .code-svg .val--hi {
  fill: var(--gold-hi);
}

.page-about .code-svg .lb {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  fill: var(--jade);
}

.page-about .code-svg .op {
  font-family: var(--font-mono);
  font-size: 20px;
  fill: var(--jade);
}

.page-about .code-svg .rule {
  stroke: var(--line);
  stroke-width: 1;
}

.page-about .code-svg .arrow {
  fill: var(--gold);
}

.page-about .about-plate {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--deep);
}

.page-about .about-plate img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 12 / 8;
  object-fit: cover;
}

.page-about .about-plate figcaption {
  padding: 10px 12px;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  line-height: 1.6;
  color: var(--jade);
}

.page-about .range-note {
  margin-top: 32px;
  padding: 24px 20px;
  background: var(--panel);
  border-left: 2px solid var(--cinnabar);
}

.page-about .range-note h3 {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 18px;
  color: var(--paper);
}

.page-about .range-scale {
  list-style: none;
  margin: 0 0 16px;
  padding: 0;
}

.page-about .range-scale li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 9px 0;
  border-bottom: 1px solid rgba(46, 82, 69, 0.6);
  font-size: 13px;
  line-height: 1.7;
  color: var(--jade);
}

.page-about .range-scale li:last-child {
  border-bottom: 0;
}

.page-about .range-dot {
  flex: none;
  width: 10px;
  height: 10px;
  background: var(--cinnabar);
}

.page-about .about-sec .range-note__link {
  margin: 0;
  font-size: 13px;
  color: var(--jade);
}

/* ---------- 05 归属与备案 ---------- */
.page-about .legal-list {
  margin: 0;
  border-top: 1px solid var(--line);
}

.page-about .legal-list__row {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 6px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .legal-list dt {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--gold);
}

.page-about .legal-list dd {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: rgba(237, 231, 218, 0.82);
}

.page-about .about-sec .legal-list dd .num {
  font-size: 15px;
  letter-spacing: 0.1em;
}

.page-about .about-sec .legal-note {
  margin-top: 22px;
  padding-left: 14px;
  border-left: 2px solid var(--line);
  font-size: 13px;
  line-height: 1.85;
  color: var(--jade);
}

/* ---------- 页尾索引链 ---------- */
.page-about .about-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 24px;
  padding: 28px 0 56px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
}

.page-about .about-links a {
  color: var(--gold);
  text-decoration: none;
  padding-bottom: 2px;
  border-bottom: 1px solid rgba(201, 162, 75, 0.35);
}

.page-about .about-links a:hover,
.page-about .about-links a:focus-visible {
  color: var(--gold-hi);
  border-bottom-color: var(--gold-hi);
}

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

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

@media (min-width: 860px) {
  .page-about .about-hero {
    padding: 46px 0 40px;
  }

  .page-about .about-sec {
    padding: 58px 0;
  }

  .page-about .about-sec__head {
    gap: 22px;
    margin-bottom: 32px;
  }

  .page-about .crew-grid {
    grid-template-columns: 5fr 4fr 3fr;
  }

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

  .page-about .about-workbench img {
    height: 100%;
    aspect-ratio: auto;
  }

  .page-about .about-workbench figcaption {
    padding: 28px 26px;
    display: flex;
    flex-direction: column;
    justify-content: center;
  }

  .page-about .legal-list__row {
    grid-template-columns: 130px minmax(0, 1fr);
    gap: 20px;
  }

  .page-about .legal-list dt {
    padding-top: 3px;
  }
}

@media (min-width: 1000px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-timeline-wrap {
    grid-template-columns: minmax(0, 4fr) minmax(0, 7fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .about-timeline__media {
    position: sticky;
    top: 92px;
  }

  .page-about .codes-wrap {
    grid-template-columns: minmax(0, 8fr) minmax(0, 5fr);
    gap: 44px;
    align-items: start;
  }

  .page-about .about-plate {
    position: sticky;
    top: 92px;
  }

  .page-about .range-note {
    padding: 28px 26px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .timeline__item,
  .page-about .timeline__item::before,
  .page-about .stage-ticks a {
    transition: none;
  }

  .page-about .timeline__item {
    opacity: 1;
  }
}
<<<END>>>