.page-about {
  --about-rail-w: 176px;
  --about-sticky-top: 92px;
  background: var(--ink);
  color: var(--paper);
  font-family: var(--font-body);
  overflow-x: clip;
}

.page-about .mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb {
  padding: 18px 0 0;
}
.page-about .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.06em;
}
.page-about .breadcrumb__link {
  color: var(--muted);
  text-decoration: none;
  transition: color var(--dur) var(--ease);
}
.page-about .breadcrumb__link:hover,
.page-about .breadcrumb__link:focus-visible {
  color: var(--lime);
}
.page-about .breadcrumb__sep {
  color: var(--line-strong);
}
.page-about .breadcrumb__item span[aria-current="page"] {
  color: var(--paper);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: 30px 0 36px;
  border-bottom: 1px solid var(--line);
}
.page-about .about-hero__kicker {
  color: var(--amber);
  margin: 0 0 12px;
}
.page-about .about-hero__title {
  margin: 0;
  font-size: clamp(2rem, 8vw, 3.5rem);
  line-height: 1.12;
  font-weight: 800;
  letter-spacing: -0.025em;
  max-width: 15em;
}
.page-about .about-hero__title em {
  font-style: normal;
  color: var(--lime);
  border-bottom: 2px solid rgba(200, 255, 77, 0.42);
  padding-bottom: 2px;
}
.page-about .about-hero__lede {
  margin: 20px 0 0;
  max-width: 36em;
  color: var(--muted);
  font-size: var(--fs-17);
  line-height: 1.8;
}
.page-about .about-hero__stats {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}
.page-about .about-hero__stat {
  background: var(--ink-2);
  padding: 14px 16px;
}
.page-about .about-hero__num {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--fs-28);
  line-height: 1.1;
  color: var(--lime);
  letter-spacing: -0.02em;
}
.page-about .about-hero__cap {
  display: block;
  margin-top: 6px;
  font-size: var(--fs-12);
  letter-spacing: 0.1em;
  color: var(--muted);
}

/* ---------- 主体骨架：竖排索引 + 连续长文 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 32px;
  padding-top: 32px;
}
.page-about .about-rail {
  border-top: 1px solid var(--line-strong);
  padding-top: 12px;
}
.page-about .about-rail__title {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--muted);
}
.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 8px;
  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: baseline;
  gap: 8px;
  white-space: nowrap;
  padding: 9px 12px;
  border: 1px solid var(--line);
  color: var(--muted);
  text-decoration: none;
  font-size: var(--fs-14);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease),
    background-color var(--dur) var(--ease);
}
.page-about .about-rail__idx {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  color: var(--amber);
}
.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--lime);
  border-color: var(--lime);
  background: rgba(200, 255, 77, 0.06);
}

/* ---------- 章节通用 ---------- */
.page-about .about-main {
  min-width: 0;
}
.page-about .about-sec {
  position: relative;
  padding: 34px 0;
  border-top: 1px solid var(--line);
  scroll-margin-top: var(--about-sticky-top);
}
.page-about .about-sec:first-child {
  border-top: 0;
  padding-top: 0;
}
.page-about .about-sec:target {
  border-top-color: var(--amber);
}
.page-about .about-sec__num {
  display: block;
  font-size: var(--fs-12);
  letter-spacing: 0.18em;
  color: var(--amber);
  margin-bottom: 10px;
}
.page-about .about-h2 {
  margin: 0 0 14px;
  font-size: clamp(1.375rem, 4.6vw, 1.75rem);
  line-height: 1.32;
  font-weight: 800;
  letter-spacing: -0.01em;
}
.page-about p {
  margin: 0 0 14px;
  font-size: var(--fs-17);
  line-height: 1.78;
  max-width: 36em;
}
.page-about p:last-child {
  margin-bottom: 0;
}

/* ---------- 引述 ---------- */
.page-about .about-quote {
  margin: 24px 0 0;
  padding: 20px 20px 20px 22px;
  background: var(--gem-wine);
  border-left: 2px solid var(--lime);
  font-size: var(--fs-21);
  line-height: 1.58;
  color: var(--paper);
  max-width: 32em;
}

/* ---------- 团队分工 ---------- */
.page-about .about-team {
  display: grid;
  gap: 26px;
  margin-top: 22px;
}
.page-about .about-roles {
  list-style: none;
  margin: 0;
  padding: 0;
}
.page-about .about-roles__item {
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  gap: 14px;
  padding: 16px 0;
  border-top: 1px solid var(--line);
}
.page-about .about-roles__item:first-child {
  border-top: 1px solid var(--line-strong);
}
.page-about .about-roles__num {
  font-family: var(--font-mono);
  font-size: var(--fs-28);
  line-height: 1;
  color: var(--lime);
  letter-spacing: -0.03em;
}
.page-about .about-roles__name {
  margin: 0 0 6px;
  font-size: var(--fs-17);
  font-weight: 700;
}
.page-about .about-roles__item p {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.72;
  color: var(--muted);
  max-width: 34em;
}
.page-about .about-team__fig {
  margin: 0;
}
.page-about .about-team__fig .media__frame {
  border: 1px solid var(--line);
  background: var(--ink-2);
  overflow: hidden;
}
.page-about .about-team__fig .media__img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  filter: saturate(0.82) contrast(1.06);
}
.page-about .about-team__fig .media__cap {
  margin-top: 8px;
  font-size: var(--fs-12);
  color: var(--muted);
  letter-spacing: 0.04em;
}

/* ---------- 赛季节奏（深色图文带） ---------- */
.page-about .about-rhythm {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  margin: 12px 0 0;
  padding: 40px 20px;
  background: var(--ink-2);
  border-top: 0;
}
.page-about .about-rhythm__img {
  position: absolute;
  inset: 0;
  z-index: -1;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.26;
  filter: grayscale(0.35) contrast(1.1);
}
.page-about .about-rhythm__inner {
  position: relative;
  max-width: 62em;
}
.page-about .about-rhythm p {
  color: var(--paper);
}
.page-about .about-phases {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}
.page-about .about-phase {
  background: rgba(10, 21, 18, 0.88);
  padding: 20px 18px;
  border-top: 2px solid transparent;
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}
.page-about .about-phase:hover {
  border-top-color: var(--amber);
  background: rgba(16, 36, 29, 0.94);
}
.page-about .about-phase__time {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.12em;
  color: var(--amber);
  text-transform: uppercase;
}
.page-about .about-phase__name {
  margin: 10px 0 8px;
  font-size: var(--fs-21);
  font-weight: 700;
  line-height: 1.35;
}
.page-about .about-phase p {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.72;
  color: var(--muted);
}

/* ---------- 校对与数字 ---------- */
.page-about .about-check {
  margin: 36px 0 0;
  padding: 30px 20px;
  background: var(--gem-teal);
  border-top: 2px solid var(--lime);
}
.page-about .about-check p {
  color: var(--paper);
}
.page-about .about-stats {
  list-style: none;
  margin: 26px 0 0;
  padding: 22px 0 0;
  border-top: 1px solid var(--line-strong);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px 18px;
}
.page-about .about-stats__num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.75rem, 6vw, 2.5rem);
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--lime);
}
.page-about .about-stats__unit {
  display: block;
  margin-top: 8px;
  font-size: var(--fs-12);
  letter-spacing: 0.1em;
  color: var(--muted);
}

/* ---------- 版本历程：横向斜切时间轴 ---------- */
.page-about .about-versions {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  margin-top: 44px;
  padding: 48px 0 44px;
  background: var(--structure);
}
.page-about .about-versions::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background: linear-gradient(112deg, rgba(20, 50, 43, 0.92) 0%, rgba(62, 18, 32, 0.55) 58%, rgba(10, 21, 18, 0) 100%);
  clip-path: polygon(0 5%, 100% 0, 100% 95%, 0 100%);
}
.page-about .about-versions__back {
  position: absolute;
  inset: 0;
  z-index: -2;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.16;
  filter: grayscale(0.4) contrast(1.05);
}
.page-about .about-versions__inner {
  position: relative;
}
.page-about .about-versions__lede {
  color: var(--muted);
  max-width: 34em;
}
.page-about .about-tl__list {
  list-style: none;
  margin: 30px 0 0;
  padding: 0 0 12px;
  display: flex;
  gap: 16px;
  overflow-x: auto;
  scroll-snap-type: x proximity;
}
.page-about .about-tl__item {
  flex: 0 0 76vw;
  max-width: 320px;
  scroll-snap-align: start;
}
.page-about .about-tl__node {
  border-top: 1px solid var(--line-strong);
  position: relative;
}
.page-about .about-tl__sum {
  display: block;
  position: relative;
  padding: 18px 0 0;
  cursor: pointer;
  list-style: none;
}
.page-about .about-tl__sum::-webkit-details-marker {
  display: none;
}
.page-about .about-tl__dot {
  position: absolute;
  top: -5px;
  left: 0;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--amber);
  box-shadow: 0 0 0 4px rgba(255, 162, 58, 0.16);
  transition: background-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
.page-about .about-tl__node[open] .about-tl__dot {
  background: var(--lime);
  box-shadow: 0 0 0 5px rgba(200, 255, 77, 0.18);
}
.page-about .about-tl__v {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--amber);
}
.page-about .about-tl__name {
  display: block;
  margin-top: 8px;
  font-size: var(--fs-14);
  font-weight: 700;
  line-height: 1.5;
  color: var(--paper);
  transition: color var(--dur) var(--ease);
}
.page-about .about-tl__sum:hover .about-tl__name,
.page-about .about-tl__sum:focus-visible .about-tl__name {
  color: var(--lime);
}
.page-about .about-tl__desc {
  margin: 10px 0 0;
  font-size: var(--fs-14);
  line-height: 1.72;
  color: var(--muted);
  max-width: 30em;
}
.page-about .about-versions__note {
  margin: 24px 0 0;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  font-size: var(--fs-14);
  color: var(--muted);
  max-width: 40em;
}

/* ---------- 出口导航 ---------- */
.page-about .about-next {
  padding: 48px 0 56px;
}
.page-about .about-next__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: 22px;
  background: var(--line);
  border: 1px solid var(--line);
}
.page-about .about-next__link {
  display: block;
  padding: 20px 18px;
  background: var(--ink-2);
  color: var(--paper);
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: background-color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  background: var(--gem-teal);
  border-left-color: var(--lime);
}
.page-about .about-next__k {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--amber);
}
.page-about .about-next__t {
  display: block;
  margin: 8px 0 6px;
  font-size: var(--fs-17);
  font-weight: 700;
}
.page-about .about-next__d {
  display: block;
  font-size: var(--fs-14);
  line-height: 1.65;
  color: var(--muted);
}

/* ---------- 断点 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .about-phases {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .about-next__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 860px) {
  .page-about .about-body {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: 52px;
    padding-top: 40px;
  }
  .page-about .about-rail {
    position: sticky;
    top: var(--about-sticky-top);
    align-self: start;
    padding-top: 6px;
  }
  .page-about .about-rail__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
  }
  .page-about .about-rail__link {
    border: 0;
    border-left: 1px solid var(--line);
    padding: 10px 0 10px 14px;
    white-space: normal;
    background: none;
  }
  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    border-left-color: var(--lime);
    background: none;
  }
  .page-about .about-team {
    grid-template-columns: minmax(0, 1fr) 320px;
    gap: 36px;
    align-items: start;
  }
  .page-about .about-rhythm {
    padding: 48px 32px;
  }
  .page-about .about-check {
    padding: 36px 30px;
  }
}

@media (min-width: 1000px) {
  .page-about .about-tl__list {
    display: grid;
    grid-template-columns: repeat(7, minmax(0, 1fr));
    gap: 14px;
    overflow: visible;
    padding-bottom: 0;
  }
  .page-about .about-tl__item {
    flex: none;
    max-width: none;
  }
  .page-about .about-versions {
    padding: 64px 0 56px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-phase,
  .page-about .about-tl__dot,
  .page-about .about-tl__name,
  .page-about .about-next__link,
  .page-about .about-rail__link {
    transition-duration: 1ms;
  }
}
<<<END>>>