.page-about {
  --about-gap: clamp(18px, 3vw, 32px);
  --about-radius: 18px;
  --about-sticky: 104px;
  color: var(--mist);
  background:
    radial-gradient(120% 55% at 84% -6%, rgba(47, 243, 208, 0.10), transparent 62%),
    radial-gradient(88% 46% at 2% 4%, rgba(255, 90, 54, 0.07), transparent 58%),
    var(--ink);
  padding-top: clamp(84px, 10vw, 112px);
  padding-bottom: clamp(48px, 7vw, 88px);
  overflow-x: clip;
}

.page-about h2 {
  font-family: var(--font-display);
  font-size: clamp(1.55rem, 4vw, 2.25rem);
  line-height: 1.22;
  letter-spacing: -0.01em;
  font-weight: 700;
  margin: 8px 0 10px;
  max-width: 24ch;
}

.page-about p {
  line-height: 1.8;
}

.page-about .about-crumb {
  margin-bottom: clamp(6px, 1.6vw, 14px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-bottom: clamp(30px, 5vw, 54px);
}

.page-about .hero-grid {
  display: grid;
  gap: var(--about-gap);
}

.page-about .hero-title {
  font-family: var(--font-display);
  font-size: clamp(2.05rem, 6.4vw, 3.5rem);
  line-height: 1.1;
  letter-spacing: -0.025em;
  font-weight: 700;
  margin: 10px 0 16px;
  color: var(--mist);
}

.page-about .hero-lede {
  max-width: 48ch;
  font-size: clamp(1rem, 2.1vw, 1.0625rem);
  color: var(--mist-72);
  margin: 0;
}

.page-about .hero-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 1px;
  margin: clamp(22px, 4vw, 34px) 0 0;
  padding: 0;
  list-style: none;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.page-about .hero-stat {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 16px 18px;
  background: var(--ink-2);
}

.page-about .hero-stat-num {
  font-family: var(--font-mono);
  font-size: clamp(1.35rem, 4vw, 1.85rem);
  font-weight: 600;
  line-height: 1.1;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .hero-stat-label {
  font-size: 0.8125rem;
  line-height: 1.55;
  color: var(--mist-56);
}

.page-about .hero-card {
  position: relative;
  overflow: hidden;
  padding: clamp(20px, 3.4vw, 30px);
  border: 1px solid var(--line-cyan);
  border-radius: var(--radius-lg);
  background: linear-gradient(158deg, rgba(30, 48, 59, 0.92), rgba(16, 26, 34, 0.74));
  align-self: start;
}

.page-about .hero-card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: linear-gradient(90deg, var(--cyan), rgba(47, 243, 208, 0) 72%);
}

.page-about .hero-card::after {
  content: "2019 / 2025";
  position: absolute;
  right: 10px;
  bottom: -10px;
  font-family: var(--font-mono);
  font-size: clamp(1.9rem, 6.4vw, 3rem);
  letter-spacing: 0.04em;
  color: rgba(47, 243, 208, 0.10);
  pointer-events: none;
}

.page-about .hero-card-quote {
  position: relative;
  z-index: 1;
  margin: 0 0 18px;
  font-family: var(--font-display);
  font-size: clamp(1.0625rem, 2.6vw, 1.3rem);
  line-height: 1.65;
  color: var(--mist);
}

.page-about .hero-tags {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

/* ---------- 年表层叠目录 ---------- */
.page-about .dossier {
  display: grid;
  gap: clamp(22px, 4vw, 44px);
  padding-block: clamp(30px, 5vw, 52px);
  border-top: 1px solid var(--line);
}

.page-about .index-title {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.page-about .index-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 6px;
  margin: 12px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .index-link {
  display: flex;
  gap: 8px;
  align-items: baseline;
  padding: 9px 10px;
  border: 1px solid transparent;
  border-radius: 10px;
  font-size: 0.8125rem;
  line-height: 1.45;
  color: var(--mist-72);
  text-decoration: none;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease), background 0.18s var(--ease);
}

.page-about .index-link:hover,
.page-about .index-link:focus-visible {
  color: var(--cyan);
  border-color: var(--line-cyan);
  background: rgba(47, 243, 208, 0.07);
}

.page-about .index-num {
  flex: none;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--ember);
  font-variant-numeric: tabular-nums;
}

.page-about .dossier-body {
  display: grid;
  gap: clamp(26px, 4vw, 42px);
}

.page-about .chronicle {
  scroll-margin-top: var(--about-sticky);
  padding-bottom: clamp(24px, 3.6vw, 38px);
  border-bottom: 1px solid var(--line);
}

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

.page-about .chronicle-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 16px;
  margin-bottom: 12px;
}

.page-about .chronicle-year {
  font-family: var(--font-mono);
  font-size: clamp(1.4rem, 4vw, 1.95rem);
  font-weight: 600;
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--ember);
  font-variant-numeric: tabular-nums;
}

.page-about .chronicle h2 {
  margin: 0;
  font-size: clamp(1.35rem, 3.4vw, 1.85rem);
  max-width: 20ch;
}

.page-about .chronicle p {
  max-width: 62ch;
  margin: 0 0 14px;
  color: var(--mist-72);
  font-size: 0.975rem;
}

.page-about .chronicle-link-row {
  margin-top: 6px;
}

.page-about .text-link {
  color: var(--cyan);
  font-weight: 600;
  text-decoration: none;
  border-bottom: 1px solid rgba(47, 243, 208, 0.4);
  padding-bottom: 2px;
  transition: border-color 0.18s var(--ease), color 0.18s var(--ease);
}

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

.page-about .about-figure {
  margin: 18px 0 22px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--ink-2);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-figure figcaption {
  padding: 12px 16px;
  background: var(--mist);
  color: #16212a;
  font-size: 0.8125rem;
  line-height: 1.65;
  border-left: 3px solid var(--moss);
}

.page-about .chronicle-more {
  margin-top: 4px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(16, 26, 34, 0.7);
}

.page-about .chronicle-more summary {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--cyan);
  cursor: pointer;
  list-style: none;
}

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

.page-about .chronicle-more summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 1rem;
}

.page-about .chronicle-more[open] summary::after {
  content: "−";
}

.page-about .chronicle-more-body {
  padding: 0 16px 16px;
}

.page-about .chronicle-more-body p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--mist-56);
}

/* ---------- 团队 ---------- */
.page-about .team-block,
.page-about .partners,
.page-about .reach,
.page-about .credentials {
  padding-block: clamp(34px, 5.6vw, 60px);
}

.page-about .section-head {
  margin-bottom: clamp(20px, 3vw, 32px);
}

.page-about .section-lede {
  max-width: 58ch;
  margin: 0;
  color: var(--mist-56);
  font-size: 0.95rem;
}

.page-about .team-grid {
  display: grid;
  gap: var(--about-gap);
}

.page-about .team-cards {
  display: grid;
  gap: 12px;
}

.page-about .team-card {
  position: relative;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--ink-2);
  transition: transform 0.16s var(--ease), border-color 0.16s var(--ease);
}

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

.page-about .team-card h3 {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 600;
  color: var(--mist);
}

.page-about .team-card h3::before {
  content: "";
  flex: none;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--moss);
}

.page-about .team-card:nth-child(2) h3::before { background: var(--cyan); }
.page-about .team-card:nth-child(3) h3::before { background: var(--gold); }
.page-about .team-card:nth-child(4) h3::before { background: var(--clay); }

.page-about .team-card p {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--mist-56);
}

.page-about .team-figure {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
  background: rgba(30, 48, 59, 0.5);
  align-self: start;
}

.page-about .team-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .team-figure figcaption {
  padding: 12px 16px;
  background: var(--mist);
  color: #16212a;
  font-size: 0.8125rem;
  line-height: 1.65;
  border-left: 3px solid var(--cyan);
}

.page-about .rhythm-list {
  display: grid;
  gap: 14px;
  margin: clamp(24px, 4vw, 40px) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .rhythm-step {
  padding-top: 12px;
  border-top: 2px solid var(--slate);
}

.page-about .rhythm-step:nth-child(1) { border-top-color: var(--cyan); }
.page-about .rhythm-step:nth-child(2) { border-top-color: var(--ember); }
.page-about .rhythm-step:nth-child(3) { border-top-color: var(--gold); }
.page-about .rhythm-step:nth-child(4) { border-top-color: var(--moss); }

.page-about .rhythm-num {
  display: block;
  margin-bottom: 6px;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.1em;
  color: var(--neutral);
}

.page-about .rhythm-title {
  display: block;
  font-weight: 600;
  font-size: 0.975rem;
  color: var(--mist);
}

.page-about .rhythm-text {
  margin: 5px 0 0;
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--mist-56);
}

/* ---------- 资料协作 ---------- */
.page-about .partner-grid {
  display: grid;
  gap: var(--about-gap);
}

.page-about .partner-copy p {
  max-width: 60ch;
  margin: 0 0 14px;
  color: var(--mist-72);
  font-size: 0.95rem;
}

.page-about .field-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(96px, 1fr));
  gap: 1px;
  margin: 18px 0 22px;
  padding: 0;
  list-style: none;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 12px;
  overflow: hidden;
}

.page-about .field-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 12px 10px;
  background: var(--slate);
}

.page-about .field-name {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.1em;
  color: var(--cyan);
}

.page-about .field-desc {
  font-size: 0.8125rem;
  color: var(--mist);
}

.page-about .metric-strip {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
  align-self: start;
}

.page-about .metric {
  padding: 18px 16px;
  background: var(--ink-2);
}

.page-about .metric-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.45rem, 4.4vw, 1.95rem);
  font-weight: 600;
  line-height: 1.1;
  color: var(--gold);
  font-variant-numeric: tabular-nums;
}

.page-about .metric-num small {
  margin-left: 3px;
  font-size: 0.5em;
  font-weight: 400;
  color: var(--mist-56);
}

.page-about .metric-label {
  display: block;
  margin-top: 6px;
  font-size: 0.8125rem;
  line-height: 1.55;
  color: var(--mist-56);
}

/* ---------- 服务范围 ---------- */
.page-about .reach {
  position: relative;
}

.page-about .reach-items {
  display: grid;
  gap: 14px;
}

.page-about .reach-item {
  padding-left: 14px;
  border-left: 2px solid var(--ember);
}

.page-about .reach-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 4.2vw, 2.1rem);
  font-weight: 600;
  line-height: 1.1;
  color: var(--mist);
  font-variant-numeric: tabular-nums;
}

.page-about .reach-item p {
  margin: 6px 0 0;
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--mist-56);
}

.page-about .reach-note {
  margin: clamp(20px, 3vw, 28px) 0 0;
  padding: 14px 16px;
  border: 1px dashed var(--line-cyan);
  border-radius: 12px;
  font-size: 0.9rem;
  color: var(--mist-72);
  background: rgba(47, 243, 208, 0.05);
}

/* ---------- 资质与联系 ---------- */
.page-about .cred-grid {
  display: grid;
  gap: var(--about-gap);
  padding-top: clamp(26px, 4vw, 42px);
  border-top: 1px solid var(--line);
}

.page-about .cred-main p {
  max-width: 54ch;
  color: var(--mist-72);
  font-size: 0.95rem;
}

.page-about .cred-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 20px;
}

.page-about .cred-list {
  margin: 0;
  padding: 0;
}

.page-about .cred-item {
  display: grid;
  gap: 4px;
  padding: 14px 0;
  border-bottom: 1px dashed var(--line);
}

.page-about .cred-item:last-child {
  border-bottom: 0;
}

.page-about .cred-item dt {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.1em;
  color: var(--neutral);
}

.page-about .cred-item dd {
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.65;
  color: var(--mist);
  overflow-wrap: anywhere;
}

.page-about .copy-btn {
  padding: 6px 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: transparent;
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  text-align: left;
  overflow-wrap: anywhere;
  cursor: pointer;
  transition: border-color 0.18s var(--ease), background 0.18s var(--ease);
}

.page-about .copy-btn:hover,
.page-about .copy-btn:focus-visible {
  border-color: var(--line-cyan);
  background: rgba(47, 243, 208, 0.08);
}

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .team-cards {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .cred-item {
    grid-template-columns: 96px minmax(0, 1fr);
    align-items: baseline;
    gap: 14px;
  }

  .page-about .rhythm-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
  }
}

@media (min-width: 880px) {
  .page-about .hero-grid {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, 0.75fr);
    align-items: start;
    gap: clamp(28px, 4vw, 48px);
  }

  .page-about .dossier {
    grid-template-columns: 176px minmax(0, 1fr);
    align-items: start;
  }

  .page-about .dossier-index {
    position: sticky;
    top: var(--about-sticky);
  }

  .page-about .index-list {
    grid-template-columns: 1fr;
    gap: 4px;
  }

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

  .page-about .partner-grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    align-items: start;
  }

  .page-about .reach-items {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 22px 26px;
  }

  .page-about .cred-grid {
    grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr);
    gap: clamp(28px, 4vw, 56px);
  }
}

@media (min-width: 1080px) {
  .page-about .rhythm-list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .reach-items {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }

  .page-about .team-card:hover {
    transform: none;
  }
}