.page-about {
  --about-rail: 168px;
  --about-track-pad: 1.6rem;
  --about-gap: 3rem;
  color: var(--white);
}

.page-about .about-crumb {
  padding-block: 1.1rem 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(1.5rem, 4vw, 2.75rem) 0 clamp(2.5rem, 5vw, 4rem);
  border-bottom: 1px solid var(--hair);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    repeating-linear-gradient(90deg, rgba(30, 92, 74, 0.26) 0 1px, transparent 1px 88px),
    repeating-linear-gradient(0deg, rgba(30, 92, 74, 0.16) 0 1px, transparent 1px 88px);
  -webkit-mask-image: linear-gradient(180deg, #000 0%, transparent 78%);
  mask-image: linear-gradient(180deg, #000 0%, transparent 78%);
}

.page-about .about-hero__grid {
  position: relative;
  display: grid;
  gap: clamp(1.75rem, 4vw, 3rem);
  align-items: end;
}

@media (min-width: 960px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }
}

.page-about h1 {
  font-family: var(--font-cond);
  font-size: clamp(2.1rem, 6.6vw, 4.2rem);
  font-weight: 800;
  line-height: 1.03;
  letter-spacing: -0.015em;
  margin: 0.5rem 0 0;
  max-width: 17ch;
}

.page-about .about-hero__copy .lede {
  margin-top: 1.15rem;
  max-width: 52ch;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.75rem;
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  background: var(--hair);
  border: 1px solid var(--hair);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .stat {
  display: flex;
  flex-direction: column-reverse;
  padding: 1rem 1.05rem 1.1rem;
  background: var(--glass-fill);
}

.page-about .stat__label {
  margin-top: 0.4rem;
  font-size: 0.76rem;
  letter-spacing: 0.06em;
  color: var(--muted);
}

.page-about .stat__value {
  margin: 0;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.5rem, 4vw, 2.1rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--cyan);
}

.page-about .stat__unit {
  margin-left: 0.28em;
  font-size: 0.46em;
  color: var(--muted);
  letter-spacing: 0;
}

/* ---------- 通用标题 ---------- */
.page-about h2 {
  font-family: var(--font-cond);
  font-size: clamp(1.55rem, 4.4vw, 2.5rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.015em;
  margin: 0.4rem 0 0.7rem;
  max-width: 26ch;
}

.page-about h3 {
  font-family: var(--font-cond);
  font-weight: 700;
  letter-spacing: -0.005em;
}

/* ---------- 运营年轮 ---------- */
.page-about .about-archive {
  border-bottom: 1px solid var(--hair);
}

.page-about .about-archive__plate {
  margin: 0 0 clamp(2rem, 4vw, 3rem);
}

.page-about .about-timeline {
  display: grid;
  gap: 2rem;
}

@media (min-width: 1024px) {
  .page-about .about-timeline {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: var(--about-gap);
  }
}

.page-about .year-rail__title {
  margin: 0 0 0.7rem;
  font-size: 0.72rem;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .year-rail__list {
  display: flex;
  gap: 0.45rem;
  margin: 0;
  padding: 0 0 0.4rem;
  list-style: none;
  overflow-x: auto;
}

.page-about .year-rail__link {
  display: inline-block;
  padding: 0.32rem 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  letter-spacing: 0.06em;
  color: var(--muted);
  text-decoration: none;
  white-space: nowrap;
  border: 1px solid var(--hair);
  border-radius: 999px;
  transition: color 0.22s var(--ease), background-color 0.22s var(--ease), border-color 0.22s var(--ease);
}

.page-about .year-rail__link:hover,
.page-about .year-rail__link:focus-visible {
  color: var(--ink);
  background: var(--cyan);
  border-color: var(--cyan);
}

@media (min-width: 1024px) {
  .page-about .year-rail {
    position: sticky;
    top: calc(var(--header-h) + 1.75rem);
    align-self: start;
  }

  .page-about .year-rail__list {
    flex-direction: column;
    gap: 0.15rem;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .year-rail__link {
    display: block;
    padding: 0.3rem 0 0.3rem 0.85rem;
    border: 0;
    border-left: 1px solid var(--hair);
    border-radius: 0;
    background: transparent;
  }

  .page-about .year-rail__link:hover,
  .page-about .year-rail__link:focus-visible {
    color: var(--cyan);
    background: transparent;
    border-left-color: var(--cyan);
  }
}

.page-about .timeline-track {
  position: relative;
  padding-left: var(--about-track-pad);
}

.page-about .timeline-track::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.35rem;
  bottom: 0.4rem;
  width: 2px;
  background: linear-gradient(180deg, var(--cyan) 0%, rgba(25, 227, 194, 0.25) 38%, var(--line) 100%);
}

.page-about .tl-item {
  position: relative;
  padding-bottom: 2.1rem;
  scroll-margin-top: calc(var(--header-h) + 1.5rem);
}

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

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: calc(var(--about-track-pad) * -1);
  top: 0.42rem;
  width: 9px;
  height: 9px;
  transform: translateX(-50%);
  background: var(--ink);
  border: 2px solid var(--cyan);
  border-radius: 50%;
  box-shadow: 0 0 0 4px rgba(25, 227, 194, 0.12);
}

.page-about .tl-item__year {
  margin: 0 0 0.3rem;
  font-size: 0.95rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.page-about .tl-item__title {
  margin: 0 0 0.45rem;
  font-size: clamp(1.12rem, 3vw, 1.42rem);
}

.page-about .tl-item__text {
  margin: 0;
  max-width: 58ch;
  font-size: 0.95rem;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .tl-item--current::before {
  background: var(--signal);
  border-color: var(--signal);
  box-shadow: 0 0 0 5px rgba(255, 122, 26, 0.18);
}

.page-about .tl-item--current .tl-item__year {
  color: var(--signal);
}

/* ---------- 联赛覆盖 ---------- */
.page-about .coverage-grid {
  display: grid;
  gap: clamp(1.75rem, 4vw, 3rem);
  align-items: start;
}

@media (min-width: 900px) {
  .page-about .coverage-grid {
    grid-template-columns: minmax(0, 4fr) minmax(0, 6fr);
  }
}

.page-about .coverage-copy p {
  margin: 0 0 1rem;
  font-size: 0.96rem;
  line-height: 1.85;
  color: var(--muted);
  max-width: 54ch;
}

.page-about .coverage-copy p:first-child {
  color: var(--white);
}

.page-about .coverage-facts {
  display: grid;
  gap: 0;
  margin: 1.6rem 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--hair);
}

.page-about .coverage-facts li {
  display: flex;
  align-items: baseline;
  gap: 0.85rem;
  padding: 0.75rem 0;
  border-bottom: 1px solid var(--hair);
}

.page-about .coverage-facts .num {
  min-width: 3.6rem;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--amber);
  letter-spacing: -0.02em;
}

.page-about .coverage-facts__label {
  font-size: 0.9rem;
  color: var(--muted);
}

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

.page-about .partner-strip {
  margin-top: clamp(2rem, 4vw, 3rem);
  padding: 1.4rem clamp(1.1rem, 3vw, 2rem);
  background: var(--pitch);
  border: 1px solid var(--hair);
  border-radius: var(--radius);
}

.page-about .partner-strip__title {
  margin: 0 0 0.9rem;
  font-size: 0.72rem;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .partner-strip__list {
  display: grid;
  gap: 1rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

@media (min-width: 700px) {
  .page-about .partner-strip__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .partner-strip__list li {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  font-size: 0.92rem;
  color: var(--muted);
}

.page-about .partner-strip__list .num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 1.6rem;
  font-weight: 700;
  line-height: 1;
  color: var(--white);
  letter-spacing: -0.03em;
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  border-top: 1px solid var(--hair);
}

.page-about .role-grid {
  display: grid;
  gap: 1.15rem;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 250px), 1fr));
}

.page-about .role-card {
  position: relative;
  padding: 1.5rem 1.35rem 1.6rem;
  background: var(--glass-fill);
  border: 1px solid var(--hair);
  border-top: 2px solid var(--line);
  border-radius: var(--radius);
  transition: border-top-color 0.25s var(--ease), background-color 0.25s var(--ease), transform 0.25s var(--ease);
}

.page-about .role-card:hover {
  border-top-color: var(--cyan);
  background: rgba(18, 51, 43, 0.78);
  transform: translateY(-3px);
}

.page-about .role-card__seats {
  margin: 0 0 0.6rem;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 1.75rem;
  font-weight: 700;
  line-height: 1;
  color: var(--cyan);
  letter-spacing: -0.04em;
}

.page-about .role-card__title {
  margin: 0 0 0.55rem;
  font-size: clamp(1.05rem, 2.6vw, 1.25rem);
}

.page-about .role-card__desc {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 版本演进 ---------- */
.page-about .version-grid {
  display: grid;
  gap: 1.15rem;
}

@media (min-width: 760px) {
  .page-about .version-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .version-card {
  padding: 1.5rem 1.35rem 1.7rem;
  background: var(--pitch);
  border: 1px solid var(--hair);
  border-left: 3px solid var(--cyan);
  border-radius: var(--radius);
}

.page-about .version-card--signal {
  border-left-color: var(--signal);
}

.page-about .version-card--amber {
  border-left-color: var(--amber);
}

.page-about .version-card .tag {
  margin-bottom: 0.85rem;
}

.page-about .version-card__title {
  margin: 0 0 0.55rem;
  font-size: clamp(1.05rem, 2.6vw, 1.25rem);
}

.page-about .version-card__text {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-versions__foot {
  margin: clamp(1.5rem, 3vw, 2rem) 0 0;
  font-size: 0.92rem;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-versions__foot a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(25, 227, 194, 0.4);
}

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

/* ---------- 复核流程 ---------- */
.page-about .about-quality {
  border-top: 1px solid var(--hair);
  background: linear-gradient(180deg, rgba(14, 36, 30, 0.55), rgba(6, 17, 14, 0) 72%);
}

.page-about .quality-grid {
  display: grid;
  gap: clamp(1.75rem, 4vw, 3rem);
  align-items: start;
}

@media (min-width: 900px) {
  .page-about .quality-grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
  }
}

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

.page-about .quality-steps {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: qs;
  display: grid;
  gap: 1.6rem;
}

.page-about .quality-steps li {
  position: relative;
  padding-left: 3.1rem;
  counter-increment: qs;
}

.page-about .quality-steps li::before {
  content: counter(qs, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 0.05rem;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 1.5rem;
  font-weight: 700;
  line-height: 1;
  color: rgba(25, 227, 194, 0.6);
}

.page-about .quality-steps__title {
  margin: 0 0 0.4rem;
  font-size: 1.1rem;
}

.page-about .quality-steps p {
  margin: 0;
  font-size: 0.93rem;
  line-height: 1.85;
  color: var(--muted);
  max-width: 52ch;
}

/* ---------- 运营与协作 ---------- */
.page-about .about-base__inner {
  position: relative;
  padding: clamp(1.6rem, 4vw, 3rem);
  background:
    linear-gradient(135deg, rgba(18, 51, 43, 0.9), rgba(6, 17, 14, 0.75) 70%),
    repeating-linear-gradient(45deg, rgba(30, 92, 74, 0.22) 0 1px, transparent 1px 22px);
  border: 1px solid var(--hair);
  border-left: 3px solid var(--signal);
  border-radius: var(--radius);
}

.page-about .about-base__inner p {
  margin: 0 0 1rem;
  max-width: 62ch;
  font-size: 0.96rem;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-base__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin: 1.5rem 0 0.5rem;
}

.page-about .about-base__note {
  margin: 0;
  font-size: 0.88rem;
  color: var(--muted);
}

@media (max-width: 599px) {
  .page-about {
    --about-gap: 2rem;
    --about-track-pad: 1.25rem;
  }

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

  .page-about .about-base__actions .btn {
    width: 100%;
    justify-content: center;
  }
}