.page-about {
  position: relative;
  isolation: isolate;
  overflow-x: clip;
  background:
    linear-gradient(180deg, rgba(11, 20, 48, .92) 0%, rgba(6, 10, 24, 1) 46%),
    var(--deep);
  color: var(--glass);
}

.page-about::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(42, 53, 96, .34) 1px, transparent 1px),
    linear-gradient(90deg, rgba(42, 53, 96, .34) 1px, transparent 1px);
  background-size: 72px 72px;
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, .7), transparent 72%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, .7), transparent 72%);
}

.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(18px, 3.5vw, 44px);
  padding-block: clamp(18px, 4vw, 44px) clamp(56px, 9vw, 120px);
}

/* ---------- 左侧等宽索引栏 ---------- */
.page-about .about-rail {
  position: relative;
  min-width: 0;
}

.page-about .rail-title {
  margin: 0 0 10px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .2em;
  color: var(--mist);
}

.page-about .rail-list {
  list-style: none;
  margin: 0;
  padding: 0 0 6px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  scrollbar-width: none;
}

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

.page-about .rail-list li { flex: 0 0 auto; }

.page-about .rail-list a {
  display: flex;
  align-items: baseline;
  gap: 8px;
  white-space: nowrap;
  padding: 8px 14px;
  border: 1px solid var(--line-soft);
  border-radius: 999px;
  background: var(--glass-2);
  color: var(--mist);
  font-size: 13px;
  text-decoration: none;
  transition: color .3s var(--ease), border-color .3s var(--ease), background .3s var(--ease);
}

.page-about .rail-list a:hover,
.page-about .rail-list a:focus-visible {
  color: var(--glass);
  border-color: rgba(34, 211, 238, .55);
  background: rgba(27, 31, 75, .8);
}

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

.page-about .rail-year {
  font-family: var(--mono);
  font-size: 11px;
  color: rgba(154, 166, 201, .82);
}

/* ---------- 首屏 ---------- */
.page-about .about-body { min-width: 0; }

.page-about .about-hero {
  padding-bottom: clamp(26px, 4.5vw, 48px);
  border-bottom: 1px solid var(--line-soft);
}

.page-about .hero-kicker {
  margin: 0 0 16px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--cyan);
}

.page-about h1 {
  margin: 0;
  max-width: 18ch;
  font-size: clamp(34px, 7vw, 68px);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: -.02em;
}

.page-about .hero-lead {
  margin: 22px 0 0;
  max-width: 62ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--mist);
}

.page-about .hero-facts {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 26px;
  margin: 26px 0 0;
  padding: 0;
  font-size: 14px;
}

.page-about .hero-facts li {
  display: flex;
  align-items: baseline;
  gap: 8px;
}

.page-about .hero-facts .mono-num {
  font-family: var(--mono);
  font-size: 15px;
  color: var(--cyan);
}

.page-about .hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

/* ---------- 通用章节 ---------- */
.page-about .about-sec {
  padding-block: clamp(42px, 6.5vw, 84px);
  border-bottom: 1px solid var(--line-soft);
  scroll-margin-top: 108px;
}

.page-about .about-sec:last-of-type { border-bottom: 0; }

.page-about .sec-head { margin-bottom: clamp(14px, 2vw, 20px); }

.page-about .sec-lead {
  margin: 0;
  max-width: 64ch;
  font-size: clamp(15px, 1.5vw, 16.5px);
  line-height: 1.9;
  color: var(--mist);
}

.page-about .about-link {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(34, 211, 238, .45);
  transition: color .3s var(--ease), border-color .3s var(--ease);
}

.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  color: var(--glass);
  border-color: var(--glass);
}

/* ---------- 图片 ---------- */
.page-about .figure { margin: 0; }

.page-about .figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: var(--indigo);
  object-fit: cover;
}

.page-about .fig-caption {
  margin-top: 10px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .02em;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .about-banner { margin-block: clamp(24px, 4vw, 40px) 0; }

.page-about .about-banner img { aspect-ratio: 16 / 9; }

.page-about .about-strip { margin-top: clamp(30px, 5vw, 52px); }

.page-about .about-strip img { aspect-ratio: 8 / 3; }

/* ---------- 历程轴 ---------- */
.page-about .tl {
  list-style: none;
  position: relative;
  margin: clamp(28px, 4vw, 46px) 0 0;
  padding: 0;
}

.page-about .tl::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 6px;
  bottom: 6px;
  width: 1px;
  background: linear-gradient(180deg, var(--line-accent), var(--line-soft));
}

.page-about .tl-item {
  position: relative;
  padding: 0 0 clamp(26px, 3.6vw, 40px) 32px;
}

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

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 5px;
  width: 15px;
  height: 15px;
  background: var(--deep);
  border: 1px solid var(--violet);
}

.page-about .tl-item:last-child::before {
  background: var(--violet);
  box-shadow: 0 0 0 4px rgba(139, 92, 246, .16), 0 0 20px rgba(139, 92, 246, .55);
}

.page-about .tl-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 14px;
}

.page-about .tl-year {
  font-family: var(--mono);
  font-size: clamp(19px, 3vw, 25px);
  letter-spacing: .02em;
  color: var(--glass);
}

.page-about .tl-code {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--cyan);
  padding: 3px 9px;
  border: 1px solid rgba(34, 211, 238, .36);
  border-radius: 999px;
}

.page-about .tl-body h3 {
  margin: 10px 0 8px;
  font-size: clamp(17px, 2vw, 20px);
  font-weight: 800;
  line-height: 1.4;
}

.page-about .tl-body p {
  margin: 0;
  max-width: 64ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--mist);
}

/* ---------- 内容矩阵 ---------- */
.page-about .cat-list {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 1px;
  margin: clamp(24px, 4vw, 38px) 0 0;
  padding: 0;
  border: 1px solid var(--line-soft);
  background: var(--line-soft);
}

.page-about .cat-list li {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 14px 16px;
  background: var(--deep);
  font-size: 14px;
  color: var(--glass);
}

.page-about .cat-idx {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--violet);
}

.page-about .matrix-meta {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px 16px;
  margin: clamp(26px, 4vw, 38px) 0 0;
}

.page-about .matrix-meta div {
  padding-left: 14px;
  border-left: 2px solid var(--line-accent);
}

.page-about .matrix-meta dt {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--mist);
  margin-bottom: 6px;
}

.page-about .matrix-meta dd {
  margin: 0;
  font-size: 15px;
  color: var(--glass);
}

.page-about .matrix-meta .mono-num {
  font-family: var(--mono);
  font-size: 17px;
  color: var(--cyan);
}

.page-about .matrix-note {
  margin: clamp(22px, 3.5vw, 32px) 0 0;
  max-width: 66ch;
  font-size: 15.5px;
  line-height: 1.9;
  color: var(--mist);
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: clamp(26px, 4vw, 40px);
}

.page-about .team-card {
  padding: 20px 18px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: linear-gradient(180deg, var(--glass-1), rgba(11, 20, 48, .55));
  transition: transform .35s var(--ease), border-color .35s var(--ease), box-shadow .35s var(--ease);
}

.page-about .team-card:hover,
.page-about .team-card:focus-within {
  transform: translateY(-4px);
  border-color: rgba(34, 211, 238, .5);
  box-shadow: var(--shadow-lift);
}

.page-about .team-card__code {
  margin: 0;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--mist);
}

.page-about .team-card__name {
  margin: 12px 0 0;
  font-size: 21px;
  font-weight: 800;
}

.page-about .team-card__num {
  margin: 6px 0 12px;
  font-family: var(--mono);
  font-size: 13px;
  color: var(--mist);
}

.page-about .team-card__num .mono-num {
  font-size: 24px;
  color: var(--cyan);
  margin-right: 4px;
}

.page-about .team-card__desc {
  margin: 0 0 16px;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--glass);
}

.page-about .team-duties {
  padding-top: 14px;
  border-top: 1px dashed var(--line);
}

.page-about .team-duties__label {
  margin: 0 0 8px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--violet);
}

.page-about .team-duties ul {
  margin: 0;
  padding-left: 16px;
  display: grid;
  gap: 6px;
}

.page-about .team-duties li {
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .team-band {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  margin-top: clamp(30px, 5vw, 52px);
}

.page-about .team-figure img { aspect-ratio: 3 / 2; }

.page-about .team-band__note { min-width: 0; }

.page-about .band-kicker {
  margin: 0 0 10px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--cyan);
}

.page-about .team-band__note > p {
  margin: 0;
  max-width: 58ch;
  font-size: 15.5px;
  line-height: 1.9;
  color: var(--mist);
}

.page-about .band-list {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .band-list li {
  position: relative;
  padding-left: 20px;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--glass);
}

.page-about .band-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 8px;
  height: 1px;
  background: var(--cyan);
}

/* ---------- 高峰保障 ---------- */
.page-about .stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1px;
  margin-top: clamp(26px, 4vw, 40px);
  border: 1px solid var(--line-soft);
  background: var(--line-soft);
}

.page-about .stat {
  padding: 22px 18px;
  background: var(--night);
}

.page-about .stat-num {
  margin: 0 0 8px;
  font-family: var(--mono);
  font-size: clamp(22px, 3.2vw, 32px);
  letter-spacing: .01em;
  color: var(--glass);
}

.page-about .stat-num .mono-num { color: inherit; }

.page-about .stat--key .stat-num { color: var(--cyan); }

.page-about .stat-label {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.65;
  color: var(--mist);
}

.page-about .peak-notes {
  list-style: none;
  margin: clamp(26px, 4vw, 38px) 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .peak-notes li {
  padding: 14px 18px;
  border-left: 2px solid var(--violet);
  background: linear-gradient(90deg, rgba(27, 31, 75, .55), rgba(6, 10, 24, 0));
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .peak-notes strong {
  color: var(--glass);
  font-weight: 800;
}

/* ---------- 备案与合规 ---------- */
.page-about .cert-list {
  display: grid;
  gap: 12px;
  margin-top: clamp(26px, 4vw, 40px);
}

.page-about .cert {
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: var(--glass-2);
  overflow: hidden;
  transition: border-color .3s var(--ease);
}

.page-about .cert:hover { border-color: rgba(139, 92, 246, .45); }

.page-about .cert summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px 18px;
  font-size: 15.5px;
  font-weight: 700;
  color: var(--glass);
}

.page-about .cert summary::-webkit-details-marker { display: none; }

.page-about .cert summary::after {
  content: "＋";
  font-family: var(--mono);
  font-size: 14px;
  color: var(--cyan);
}

.page-about .cert[open] summary::after { content: "－"; }

.page-about .cert summary:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: -3px;
}

.page-about .cert-tag {
  margin-left: auto;
  padding: 3px 10px;
  border: 1px solid rgba(61, 220, 151, .38);
  border-radius: 999px;
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 400;
  letter-spacing: .04em;
  color: var(--mint);
  white-space: nowrap;
}

.page-about .cert p {
  margin: 0;
  padding: 0 18px 18px;
  max-width: 66ch;
  font-size: 15px;
  line-height: 1.9;
  color: var(--mist);
}

/* ---------- 联系 ---------- */
.page-about .talk-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: clamp(26px, 4vw, 40px);
}

.page-about .talk-card {
  padding: clamp(20px, 3vw, 28px);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-lg);
  background: linear-gradient(160deg, rgba(27, 31, 75, .78), rgba(11, 20, 48, .92));
}

.page-about .talk-card__kicker {
  margin: 0 0 12px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--violet);
}

.page-about .talk-card h3 {
  margin: 0 0 12px;
  font-size: clamp(18px, 2.2vw, 22px);
  font-weight: 800;
  line-height: 1.4;
}

.page-about .talk-card p {
  margin: 0 0 20px;
  max-width: 52ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .talk-contact {
  margin-top: 22px;
  padding: 18px 20px;
  border: 1px dashed var(--line);
  border-radius: var(--radius);
  font-family: var(--mono);
  font-size: 12.5px;
  line-height: 2;
  color: var(--mist);
  word-break: break-word;
  overflow-wrap: anywhere;
}

.page-about .talk-contact p { margin: 0; }

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .matrix-meta { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .page-about .cat-list { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .page-about .team-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .page-about .talk-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 768px) {
  .page-about .tl::before { left: 119px; }
  .page-about .tl-item { padding-left: 152px; }
  .page-about .tl-item::before { left: 112px; }
  .page-about .tl-year {
    position: absolute;
    left: 0;
    top: 0;
    width: 100px;
    text-align: right;
    font-size: 24px;
  }
  .page-about .team-band { grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr); align-items: center; }
}

@media (min-width: 1024px) {
  .page-about .about-shell {
    grid-template-columns: 208px minmax(0, 1fr);
    align-items: start;
    gap: clamp(28px, 4vw, 56px);
  }

  .page-about .about-rail {
    position: sticky;
    top: 108px;
  }

  .page-about .rail-title {
    padding-bottom: 12px;
    border-bottom: 1px solid var(--line-soft);
  }

  .page-about .rail-list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .rail-list li { flex: 1 1 auto; }

  .page-about .rail-list a {
    display: grid;
    grid-template-columns: auto 1fr;
    grid-template-areas:
      "num name"
      "num year";
    gap: 2px 10px;
    padding: 10px 0 10px 14px;
    border: 0;
    border-left: 2px solid var(--line-soft);
    border-radius: 0;
    background: transparent;
  }

  .page-about .rail-list a:hover,
  .page-about .rail-list a:focus-visible {
    border-left-color: var(--cyan);
    background: linear-gradient(90deg, rgba(34, 211, 238, .1), transparent 80%);
  }

  .page-about .rail-num { grid-area: num; align-self: center; }
  .page-about .rail-name { grid-area: name; color: var(--glass); font-size: 14px; }
  .page-about .rail-year { grid-area: year; }
}