.page-about {
  --about-rail: 208px;
  --about-paper: rgba(255, 255, 255, 0.035);
  position: relative;
  overflow-x: hidden;
  color: var(--mist);
  background: var(--ink);
  padding-bottom: clamp(40px, 6vw, 84px);
}

.page-about img {
  display: block;
  max-width: 100%;
  height: auto;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  padding: clamp(18px, 4vw, 34px) 0 clamp(32px, 6vw, 62px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(1100px 420px at 84% -12%, rgba(67, 224, 206, 0.14), transparent 62%),
    radial-gradient(720px 380px at 2% 8%, rgba(108, 99, 232, 0.16), transparent 68%),
    radial-gradient(900px 520px at 50% 120%, rgba(62, 85, 104, 0.34), transparent 72%);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(22px, 4vw, 44px);
  margin-top: clamp(16px, 3vw, 26px);
}

.page-about .about-hero__eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .about-hero__title {
  margin: 16px 0 0;
  font-size: clamp(32px, 7vw, 60px);
  line-height: 1.06;
  letter-spacing: -0.038em;
  font-weight: 800;
  color: var(--glass);
  text-wrap: balance;
}

.page-about .about-hero__title-sub {
  display: block;
  margin-top: 0.14em;
  font-size: 0.72em;
  letter-spacing: -0.03em;
  color: var(--gold);
}

.page-about .about-hero__lead {
  margin: 18px 0 0;
  max-width: 34em;
  font-size: clamp(15px, 1.7vw, 16.5px);
  line-height: 1.85;
  color: var(--mist);
}

.page-about .about-hero__visual {
  position: relative;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line-soft);
  box-shadow: var(--shadow-float);
}

.page-about .about-hero__visual img {
  width: 100%;
  aspect-ratio: 14 / 9;
  object-fit: cover;
}

.page-about .about-hero__visual::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(180deg, rgba(8, 11, 16, 0) 38%, rgba(8, 11, 16, 0.78) 100%);
}

.page-about .about-hero__badge {
  position: absolute;
  left: 14px;
  bottom: 14px;
  z-index: 2;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--glass);
  padding: 5px 10px;
  border: 1px solid rgba(244, 247, 249, 0.26);
  border-radius: 3px;
  background: rgba(8, 11, 16, 0.52);
  backdrop-filter: blur(6px);
}

.page-about .about-hero__facts {
  list-style: none;
  margin: clamp(24px, 3.4vw, 34px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line-faint);
  border: 1px solid var(--line-faint);
  border-radius: 10px;
  overflow: hidden;
}

.page-about .about-hero__facts li {
  background: var(--ink-soft);
  padding: 14px 14px 16px;
}

.page-about .about-hero__fact-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(20px, 2.7vw, 26px);
  font-weight: 500;
  letter-spacing: -0.02em;
  color: var(--glass);
}

.page-about .about-hero__fact-num small {
  font-size: 0.55em;
  margin-left: 2px;
  color: var(--cyan);
}

.page-about .about-hero__fact-label {
  display: block;
  margin-top: 4px;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--mist);
  opacity: 0.7;
}

/* ---------- 章节导航 + 长卷 ---------- */
.page-about .about-flow {
  display: grid;
  gap: clamp(26px, 4vw, 42px);
  padding-top: clamp(30px, 5vw, 56px);
}

.page-about .about-rail {
  align-self: start;
}

.page-about .about-rail__title {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--line);
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0 0 2px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  scrollbar-width: none;
}

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

.page-about .about-rail__list a {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding: 7px 12px;
  border: 1px solid var(--line-faint);
  border-radius: 999px;
  font-size: 13px;
  line-height: 1.4;
  color: var(--mist);
  text-decoration: none;
  white-space: nowrap;
  transition: border-color 0.18s var(--ease), color 0.18s var(--ease), background-color 0.18s var(--ease);
}

.page-about .about-rail__list a span {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--gold);
}

.page-about .about-rail__list a:hover,
.page-about .about-rail__list a:focus-visible {
  border-color: rgba(230, 180, 94, 0.5);
  background: rgba(230, 180, 94, 0.08);
  color: var(--glass);
}

.page-about .about-chapters {
  display: grid;
  gap: clamp(34px, 5vw, 62px);
  min-width: 0;
}

.page-about .chapter {
  position: relative;
  scroll-margin-top: 108px;
  min-width: 0;
}

.page-about .chapter + .chapter::before {
  content: "";
  position: absolute;
  top: calc(-1 * clamp(17px, 2.5vw, 31px));
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--line-soft), rgba(111, 135, 153, 0.06) 72%, transparent);
}

.page-about .chapter__head {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.page-about .chapter__no {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.1em;
  color: var(--gold);
  padding: 3px 8px;
  border: 1px solid rgba(230, 180, 94, 0.36);
  border-radius: 3px;
  background: rgba(230, 180, 94, 0.07);
}

.page-about .chapter__kicker {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--line);
}

.page-about .chapter__title {
  margin: 14px 0 0;
  font-size: clamp(23px, 3.4vw, 34px);
  line-height: 1.24;
  letter-spacing: -0.026em;
  font-weight: 800;
  color: var(--glass);
  text-wrap: balance;
}

.page-about .chapter__text {
  margin: 16px 0 0;
  max-width: 40em;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .chapter__text a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(67, 224, 206, 0.4);
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .chapter__text a:hover,
.page-about .chapter__text a:focus-visible {
  color: var(--cyan-bright);
  border-bottom-color: var(--cyan-bright);
}

/* ---------- 双栏：时间轴 / 图片 ---------- */
.page-about .about-split {
  display: grid;
  gap: clamp(22px, 3.6vw, 38px);
  margin-top: clamp(22px, 3vw, 32px);
}

.page-about .about-timeline {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 2px 0 0 26px;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 5.5px;
  top: 8px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, var(--gold) 0%, var(--cyan) 52%, rgba(111, 135, 153, 0.12) 100%);
}

.page-about .about-timeline__item {
  position: relative;
  padding-bottom: 26px;
}

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

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 8px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--ink);
  border: 1px solid var(--cyan);
  transition: background-color 0.2s var(--ease), box-shadow 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-timeline__item:hover::before,
.page-about .about-timeline__item:focus-within::before {
  background: var(--gold);
  border-color: var(--gold-bright);
  box-shadow: 0 0 0 4px rgba(230, 180, 94, 0.14);
}

.page-about .about-timeline__year {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.1em;
  color: var(--cyan);
  margin-bottom: 5px;
}

.page-about .about-timeline__title {
  margin: 0;
  font-size: 16px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--glass);
}

.page-about .about-timeline__text {
  margin: 6px 0 0;
  max-width: 34em;
  font-size: 14px;
  line-height: 1.78;
  color: var(--mist);
  opacity: 0.88;
}

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

.page-about .about-shot img {
  width: 100%;
  border-radius: 10px;
  border: 1px solid var(--line-soft);
  object-fit: cover;
  box-shadow: 0 16px 44px -26px rgba(0, 0, 0, 0.9);
}

.page-about .about-shot--wide {
  margin-top: clamp(24px, 3.4vw, 34px);
}

.page-about .about-shot__cap {
  margin: 10px 0 0;
  font-size: 12.5px;
  line-height: 1.65;
  color: var(--line);
}

/* ---------- 会员层叠卡 ---------- */
.page-about .tier-stack {
  list-style: none;
  margin: clamp(22px, 3vw, 30px) 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .tier {
  position: relative;
  padding: clamp(16px, 2.6vw, 22px) clamp(16px, 2.6vw, 24px);
  border: 1px solid var(--line-soft);
  border-left-width: 3px;
  border-left-style: solid;
  border-radius: 10px 10px 12px 12px;
  background:
    repeating-linear-gradient(180deg, rgba(255, 255, 255, 0.022) 0 1px, transparent 1px 6px),
    linear-gradient(160deg, rgba(255, 255, 255, 0.075), rgba(255, 255, 255, 0.018));
  background-color: var(--ink-soft);
  transition: transform 0.22s var(--ease), box-shadow 0.22s var(--ease), border-color 0.22s var(--ease);
}

.page-about .tier:hover,
.page-about .tier:focus-within {
  transform: translateY(-4px);
  box-shadow: var(--shadow-glow);
}

.page-about .tier--01 { border-left-color: var(--mist); }
.page-about .tier--02 { border-left-color: var(--cyan); }
.page-about .tier--03 { border-left-color: var(--gold); }
.page-about .tier--04 { border-left-color: var(--violet-soft); }

.page-about .tier__top {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}

.page-about .tier__name {
  margin: 0;
  font-size: clamp(17px, 2.2vw, 19px);
  font-weight: 800;
  letter-spacing: -0.012em;
  color: var(--glass);
}

.page-about .tier__meta {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--line);
}

.page-about .tier__line {
  margin: 8px 0 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--mist);
  opacity: 0.9;
}

.page-about .tier__list {
  list-style: none;
  margin: 12px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.page-about .tier__list li {
  font-size: 12px;
  line-height: 1.5;
  padding: 4px 9px;
  border-radius: 4px;
  border: 1px solid var(--line-faint);
  background: rgba(255, 255, 255, 0.035);
  color: var(--mist);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  display: grid;
  gap: 1px;
  margin-top: clamp(22px, 3vw, 30px);
  background: var(--line-faint);
  border: 1px solid var(--line-faint);
  border-radius: 10px;
  overflow: hidden;
}

.page-about .about-team__cell {
  background: var(--ink-panel);
  padding: 16px 16px 18px;
}

.page-about .about-team__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(19px, 2.6vw, 24px);
  font-weight: 500;
  letter-spacing: -0.02em;
  color: var(--glass);
}

.page-about .about-team__num small {
  font-size: 0.5em;
  margin-left: 2px;
  color: var(--cyan);
}

.page-about .about-team__cap {
  display: block;
  margin-top: 5px;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--mist);
  opacity: 0.7;
}

/* ---------- 生态 ---------- */
.page-about .about-eco {
  display: grid;
  gap: 14px;
  margin-top: clamp(22px, 3vw, 30px);
}

.page-about .about-eco__item {
  position: relative;
  padding: 20px 18px 22px;
  border: 1px solid var(--line-faint);
  border-radius: 10px;
  background: linear-gradient(150deg, rgba(67, 224, 206, 0.07), rgba(255, 255, 255, 0.014) 62%);
}

.page-about .about-eco__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(28px, 4.4vw, 40px);
  font-weight: 500;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--cyan);
}

.page-about .about-eco__name {
  margin: 10px 0 0;
  font-size: 15px;
  font-weight: 700;
  color: var(--glass);
  letter-spacing: -0.01em;
}

.page-about .about-eco__text {
  margin: 8px 0 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--mist);
  opacity: 0.86;
}

.page-about .about-award {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  margin-top: 16px;
  padding: 16px 18px;
  border-left: 2px solid var(--gold);
  border-radius: 0 8px 8px 0;
  background: linear-gradient(90deg, rgba(230, 180, 94, 0.09), rgba(230, 180, 94, 0));
}

.page-about .about-award__label {
  flex: none;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--gold);
  padding: 2px 7px;
  border: 1px solid rgba(230, 180, 94, 0.34);
  border-radius: 3px;
}

.page-about .about-award__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist);
}

/* ---------- 收束 ---------- */
.page-about .chapter--end {
  padding-top: clamp(22px, 3vw, 32px);
}

.page-about .about-cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: clamp(20px, 3vw, 28px);
}

.page-about .about-cta-row .btn {
  flex: 0 1 auto;
}

/* ---------- 断点 ---------- */
@media (min-width: 620px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

@media (min-width: 760px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.6fr);
    align-items: start;
  }

  .page-about .about-shot:not(.about-shot--wide) {
    position: sticky;
    top: 96px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.04fr) minmax(0, 0.96fr);
    align-items: end;
  }

  .page-about .tier-stack {
    gap: 10px;
  }

  .page-about .tier--02 { margin-left: 36px; }
  .page-about .tier--03 { margin-left: 72px; }
  .page-about .tier--04 { margin-left: 108px; }
}

@media (min-width: 1024px) {
  .page-about .about-flow {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(32px, 4vw, 58px);
  }

  .page-about .about-rail {
    position: sticky;
    top: 96px;
  }

  .page-about .about-rail__list {
    display: block;
    overflow: visible;
  }

  .page-about .about-rail__list li + li {
    margin-top: 4px;
  }

  .page-about .about-rail__list a {
    display: flex;
    width: 100%;
    box-sizing: border-box;
    padding: 7px 0 7px 14px;
    border: 0;
    border-left: 1px solid var(--line-faint);
    border-radius: 0;
    white-space: normal;
    background: transparent;
  }

  .page-about .about-rail__list a:hover,
  .page-about .about-rail__list a:focus-visible {
    border-left-color: var(--gold);
    background: linear-gradient(90deg, rgba(230, 180, 94, 0.1), transparent 80%);
  }
}

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

  .page-about .tier:hover,
  .page-about .tier:focus-within {
    transform: none;
  }
}