.page-about {
  --about-fg: #F4EBDD;
  --about-muted: rgba(244, 235, 221, 0.62);
  --about-line: rgba(140, 107, 47, 0.5);
  --about-ink-muted: rgba(14, 27, 44, 0.72);
  background: var(--ink);
  color: var(--paper);
  font-family: var(--font-body);
  overflow-x: hidden;
  padding-bottom: 0;
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-top: 26px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--about-muted);
}

.page-about .about-crumb a {
  color: var(--gold);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 180ms var(--ease);
}

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

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: 36px;
  padding-top: clamp(28px, 4vw, 44px);
  padding-bottom: clamp(40px, 6vw, 64px);
}

.page-about .about-eyebrow {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--gold);
}

.page-about .about-h1 {
  margin: 0 0 22px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(30px, 5.4vw, 60px);
  line-height: 1.16;
  letter-spacing: -0.02em;
  max-width: 15em;
}

.page-about .about-lede {
  margin: 0 0 28px;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.9;
  color: var(--about-muted);
  max-width: 34em;
}

.page-about .about-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-hero-fig {
  margin: 0;
  position: relative;
  border: 1px solid var(--about-line);
  padding: 10px;
  background: rgba(27, 58, 75, 0.35);
  box-shadow: 10px 10px 0 rgba(7, 17, 28, 0.55);
}

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

.page-about .about-fig img,
.page-about .about-hero-fig img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-hero-fig img {
  aspect-ratio: 3 / 2;
}

/* ---------- 数字条 ---------- */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0 0 clamp(40px, 6vw, 72px);
  padding: 0;
  list-style: none;
  background: var(--about-line);
  border: 1px solid var(--about-line);
}

.page-about .about-stats li {
  background: var(--ink);
  padding: 20px 16px;
}

.page-about .about-stat-num {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: clamp(22px, 3vw, 30px);
  line-height: 1.1;
  color: var(--gold);
  letter-spacing: -0.01em;
}

.page-about .about-stat-label {
  display: block;
  font-size: 13px;
  line-height: 1.6;
  color: var(--about-muted);
}

/* ---------- 章节标题 ---------- */
.page-about .about-sec-head {
  max-width: 46em;
  margin-bottom: clamp(26px, 4vw, 42px);
}

.page-about .about-sec-head h2 {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(25px, 3.4vw, 38px);
  line-height: 1.28;
  letter-spacing: -0.01em;
}

.page-about .about-sec-desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--about-muted);
  max-width: 38em;
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  padding-top: clamp(40px, 6vw, 72px);
  padding-bottom: clamp(48px, 7vw, 88px);
}

.page-about .about-filter {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin: 0 0 36px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--about-line);
}

.page-about .about-filter-btn {
  font-family: var(--font-body);
  font-size: 13px;
  line-height: 1.4;
  padding: 8px 16px;
  border: 1px solid var(--about-line);
  border-radius: 999px;
  background: transparent;
  color: var(--paper);
  cursor: pointer;
  transition: background 180ms var(--ease), color 180ms var(--ease), border-color 180ms var(--ease);
}

.page-about .about-filter-btn:hover {
  border-color: var(--gold);
  color: var(--gold-light);
}

.page-about .about-filter-btn:focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: 2px;
}

.page-about .about-filter-btn[aria-pressed="true"] {
  background: var(--cinnabar);
  border-color: var(--cinnabar);
  color: #FFFFFF;
}

.page-about .about-filter-count {
  margin: 0 0 0 auto;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--about-muted);
}

.page-about .about-tl {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-tl::before {
  content: "";
  position: absolute;
  left: 11px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(180deg, var(--gold) 0%, rgba(212, 162, 76, 0.4) 58%, rgba(212, 162, 76, 0) 100%);
}

.page-about .about-tl-item {
  position: relative;
  padding-left: 38px;
  padding-bottom: 46px;
}

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

.page-about .about-tl-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 3px;
  width: 23px;
  height: 23px;
  box-sizing: border-box;
  border-radius: 50%;
  border: 1px solid var(--gold);
  background: var(--ink);
  box-shadow: 0 0 0 4px rgba(212, 162, 76, 0.1);
  transition: box-shadow 200ms var(--ease), background 200ms var(--ease);
}

.page-about .about-tl-item:hover::before {
  background: var(--tide);
  box-shadow: 0 0 0 7px rgba(212, 162, 76, 0.22);
}

.page-about .about-tl-item::after {
  content: attr(data-year);
  position: absolute;
  right: 0;
  top: -12px;
  font-family: var(--font-mono);
  font-size: clamp(50px, 8vw, 88px);
  line-height: 1;
  color: var(--gold);
  opacity: 0.08;
  pointer-events: none;
  user-select: none;
}

.page-about .about-tl-top {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
}

.page-about .about-tl-year {
  font-family: var(--font-mono);
  font-size: 15px;
  letter-spacing: 0.06em;
  color: var(--gold);
}

.page-about .about-tl-tag {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  padding: 3px 9px;
  border: 1px solid var(--about-line);
  color: var(--about-muted);
}

.page-about .about-tl-title {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(19px, 2.4vw, 25px);
  line-height: 1.4;
}

.page-about .about-tl-text {
  margin: 0 0 14px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--about-muted);
  max-width: 34em;
}

.page-about .about-tl-out {
  margin: 0;
  padding: 12px 16px;
  border-left: 2px solid var(--gold);
  background: rgba(27, 58, 75, 0.5);
  font-size: 14px;
  line-height: 1.75;
  color: var(--paper);
  max-width: 36em;
}

/* ---------- 业务版图 ---------- */
.page-about .about-lines {
  background: var(--tide);
  border-top: 1px solid var(--about-line);
  border-bottom: 1px solid var(--about-line);
  padding-top: clamp(44px, 6vw, 76px);
  padding-bottom: clamp(44px, 6vw, 76px);
}

.page-about .about-line-grid {
  display: grid;
  gap: 20px;
}

.page-about .about-line {
  position: relative;
  padding: 24px 20px 22px;
  background: rgba(7, 17, 28, 0.52);
  border: 1px solid rgba(140, 107, 47, 0.45);
  box-shadow: 6px 6px 0 rgba(7, 17, 28, 0.42);
  transition: transform 200ms var(--ease), border-color 200ms var(--ease);
}

.page-about .about-line:hover {
  transform: translateY(-2px);
  border-color: var(--gold);
}

.page-about .about-line-no {
  display: block;
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--gold);
}

.page-about .about-line h3 {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 21px;
  line-height: 1.35;
}

.page-about .about-line p {
  margin: 0 0 12px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--about-muted);
}

.page-about .about-line p.about-line-for {
  color: var(--gold-light);
  font-size: 13px;
  line-height: 1.7;
  padding-left: 12px;
  border-left: 1px solid var(--about-line);
}

.page-about .about-line-link {
  display: inline-block;
  margin-top: 4px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--gold);
  text-decoration: none;
  border-bottom: 1px solid rgba(212, 162, 76, 0.4);
  transition: color 180ms var(--ease), border-color 180ms var(--ease);
}

.page-about .about-line-link:hover {
  color: var(--gold-light);
  border-bottom-color: var(--gold-light);
}

/* ---------- 团队（浅色翻页） ---------- */
.page-about .about-team {
  --about-muted: rgba(14, 27, 44, 0.72);
  --about-line: rgba(140, 107, 47, 0.4);
  background: var(--paper);
  color: var(--ink);
  padding-top: clamp(48px, 7vw, 88px);
  padding-bottom: clamp(48px, 7vw, 88px);
}

.page-about .about-team .about-eyebrow {
  color: var(--bronze);
}

.page-about .about-team-grid {
  display: grid;
  gap: 32px;
}

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

.page-about .about-team-list li {
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  gap: 16px;
  padding-top: 18px;
  border-top: 1px solid var(--about-line);
}

.page-about .about-team-num {
  font-family: var(--font-mono);
  font-size: 26px;
  line-height: 1;
  color: var(--bronze);
}

.page-about .about-team-list h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 18px;
  line-height: 1.4;
  color: var(--ink);
}

.page-about .about-team-list p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--about-muted);
}

.page-about .about-team-fig {
  border: 1px solid var(--about-line);
  padding: 10px;
  background: #FFFFFF;
  box-shadow: 10px 10px 0 rgba(140, 107, 47, 0.16);
}

.page-about .about-team-fig img {
  aspect-ratio: 4 / 3;
}

/* ---------- 资质 ---------- */
.page-about .about-trust {
  padding-top: clamp(48px, 7vw, 88px);
  padding-bottom: clamp(48px, 7vw, 88px);
}

.page-about .about-certs {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .about-cert {
  position: relative;
  display: grid;
  gap: 10px;
  padding: 22px 20px 20px;
  background: var(--abyss);
  border: 1px solid var(--about-line);
  clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 14px, 100% 100%, 0 100%);
  transition: border-color 200ms var(--ease);
}

.page-about .about-cert:hover {
  border-color: var(--gold);
}

.page-about .about-cert-year {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.18em;
  color: var(--gold);
}

.page-about .about-cert-name {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 17px;
  line-height: 1.45;
  color: var(--paper);
}

.page-about .about-cert-note {
  font-size: 13px;
  line-height: 1.7;
  color: var(--about-muted);
}

/* ---------- 本地协作 ---------- */
.page-about .about-net {
  padding-top: clamp(48px, 7vw, 88px);
  padding-bottom: clamp(48px, 7vw, 88px);
  border-top: 1px solid var(--about-line);
  background: linear-gradient(180deg, var(--ink) 0%, var(--abyss) 100%);
}

.page-about .about-net-grid {
  display: grid;
  gap: 32px;
}

.page-about .about-net-fig {
  border: 1px solid var(--about-line);
  padding: 10px;
  background: rgba(27, 58, 75, 0.28);
}

.page-about .about-net-fig img {
  aspect-ratio: 12 / 7;
}

.page-about .about-net-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .about-net-list li {
  display: grid;
  gap: 6px;
  padding: 16px 18px;
  border: 1px solid var(--about-line);
  background: rgba(7, 17, 28, 0.45);
  transition: border-color 200ms var(--ease);
}

.page-about .about-net-list li:hover {
  border-color: var(--gold);
}

.page-about .about-net-list strong {
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.04em;
  color: var(--gold);
  font-weight: 500;
}

.page-about .about-net-list span {
  font-size: 14px;
  line-height: 1.8;
  color: var(--about-muted);
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  background: var(--abyss);
  border-top: 1px solid var(--about-line);
  padding-top: clamp(48px, 7vw, 80px);
  padding-bottom: clamp(48px, 7vw, 80px);
}

.page-about .about-cta-inner {
  max-width: 62em;
}

.page-about .about-cta h2 {
  margin: 0 0 16px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(24px, 3.2vw, 36px);
  line-height: 1.3;
  letter-spacing: -0.01em;
}

.page-about .about-cta p {
  margin: 0 0 26px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--about-muted);
  max-width: 34em;
}

/* ---------- 响应式 ---------- */
@media (min-width: 700px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: end;
    gap: 56px;
  }

  .page-about .about-team-grid {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    gap: 56px;
    align-items: start;
  }

  .page-about .about-net-grid {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
    gap: 56px;
    align-items: center;
  }

  .page-about .about-tl-item {
    padding-left: 44px;
    padding-bottom: 56px;
  }

  .page-about .about-tl-body {
    display: grid;
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
    gap: 0 36px;
  }

  .page-about .about-tl-title {
    grid-column: 1 / -1;
  }

  .page-about .about-tl-text {
    margin-bottom: 0;
  }

  .page-about .about-tl-out {
    align-self: start;
    margin-top: 2px;
  }
}

@media (min-width: 1040px) {
  .page-about .about-certs {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-line:hover,
  .page-about .about-filter-btn,
  .page-about .about-line-link,
  .page-about .about-cert,
  .page-about .about-tl-item::before {
    transition: none;
  }

  .page-about .about-line:hover {
    transform: none;
  }
}