.page-about {
  background: var(--ink);
  color: var(--text);
  overflow-x: hidden;
}

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

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

.page-about .visually-hidden-title {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(22px, 4vw, 40px) 0 clamp(30px, 6vw, 66px);
  background:
    radial-gradient(88% 72% at 88% 4%, rgba(11, 58, 46, 0.92) 0%, rgba(11, 58, 46, 0) 64%),
    radial-gradient(64% 48% at 2% 96%, rgba(56, 242, 200, 0.07) 0%, rgba(56, 242, 200, 0) 70%);
  border-bottom: 2px solid var(--line-soft);
}

.page-about .about-crumb {
  margin-bottom: clamp(20px, 4vw, 38px);
}

.page-about .breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.page-about .breadcrumb-item + .breadcrumb-item::before {
  content: "/";
  margin-right: 8px;
  color: var(--line);
}

.page-about .breadcrumb-item a {
  color: var(--muted);
  text-decoration: none;
  transition: color var(--dur) var(--ease);
}

.page-about .breadcrumb-item a:hover {
  color: var(--cyan);
}

.page-about .breadcrumb-item[aria-current="page"] {
  color: var(--text);
}

.page-about .about-hero-grid {
  display: grid;
  gap: clamp(22px, 4vw, 46px);
  align-items: center;
}

.page-about .about-eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-hero h1 {
  margin: 16px 0 0;
  font-size: clamp(2.15rem, 7.2vw, 5.2rem);
  font-weight: 250;
  line-height: 1.05;
  letter-spacing: -0.02em;
  max-width: 16ch;
}

.page-about .about-lede {
  margin: clamp(18px, 3vw, 26px) 0 0;
  font-size: clamp(0.98rem, 1.5vw, 1.1rem);
  line-height: 1.85;
  color: var(--muted);
  max-width: 46ch;
}

.page-about .about-hero-figure {
  margin: 0;
}

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

.page-about .about-index {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: clamp(26px, 4vw, 44px);
  padding-top: clamp(16px, 3vw, 24px);
  border-top: 1px solid var(--line-soft);
}

.page-about .about-index a {
  display: inline-block;
  padding: 7px 13px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--muted);
  text-decoration: none;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-index a:hover,
.page-about .about-index a:focus-visible {
  color: var(--cyan);
  border-color: var(--cyan);
  background: var(--cyan-soft);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-section {
  padding: clamp(44px, 8vw, 94px) 0;
  position: relative;
}

.page-about .about-section--plain {
  background: var(--ink);
}

.page-about .about-section--band {
  background:
    linear-gradient(180deg, rgba(14, 31, 26, 0.9), rgba(14, 31, 26, 0.55)),
    var(--ink-2);
  border-top: 2px solid var(--line-soft);
  border-bottom: 2px solid var(--line-soft);
}

.page-about .about-section--close {
  background:
    radial-gradient(80% 90% at 50% 0%, rgba(11, 58, 46, 0.75) 0%, rgba(11, 58, 46, 0) 70%),
    var(--ink);
}

.page-about .about-sec-head {
  display: grid;
  gap: clamp(22px, 4vw, 40px);
  align-items: center;
  margin-bottom: clamp(28px, 5vw, 52px);
}

.page-about .about-sec-head--simple {
  margin-bottom: clamp(24px, 4vw, 44px);
}

.page-about .about-sec-copy {
  max-width: 62ch;
}

.page-about .sec-num {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.24em;
  color: var(--cyan);
}

.page-about h2 {
  margin: 0;
  font-size: clamp(1.6rem, 4.2vw, 2.9rem);
  font-weight: 300;
  line-height: 1.18;
  letter-spacing: -0.015em;
}

.page-about .sec-lede {
  margin: 16px 0 0;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--muted);
}

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

.page-about .about-orb img {
  width: 100%;
  aspect-ratio: 1 / 1;
  object-fit: cover;
}

/* ---------- 时间线 ---------- */
.page-about .tl {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: clamp(18px, 3vw, 26px);
}

.page-about .tl::before {
  content: "";
  position: absolute;
  top: 6px;
  bottom: 6px;
  left: 9px;
  width: 2px;
  background: linear-gradient(180deg, var(--line), rgba(31, 111, 92, 0.15));
}

.page-about .tl-item {
  position: relative;
  padding-left: 44px;
  box-sizing: border-box;
}

.page-about .tl-dot {
  position: absolute;
  top: 20px;
  left: 1px;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  border: 2px solid var(--amber);
  background: var(--ink);
  box-shadow: 0 0 0 4px rgba(7, 18, 15, 0.9);
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease), background var(--dur) var(--ease);
  z-index: 1;
}

.page-about .tl-item:hover .tl-dot,
.page-about .tl-item:focus-within .tl-dot {
  transform: scale(1.15);
  background: var(--amber);
  box-shadow: 0 0 0 6px rgba(255, 162, 58, 0.16);
}

.page-about .tl-card {
  border: 2px solid var(--line-soft);
  border-radius: var(--radius-md);
  background: var(--ink-2);
  padding: clamp(16px, 2.6vw, 24px);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .tl-item:hover .tl-card,
.page-about .tl-item:focus-within .tl-card {
  transform: translateY(-3px);
  border-color: var(--line);
  box-shadow: var(--shadow-2);
}

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

.page-about .tl-year {
  font-family: var(--font-mono);
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--cyan);
}

.page-about .tl-ver {
  display: inline-block;
  padding: 3px 10px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--muted-dim);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .tl-item:hover .tl-ver,
.page-about .tl-item:focus-within .tl-ver {
  color: var(--amber);
  border-color: var(--amber);
}

.page-about .tl-title {
  margin: 12px 0 8px;
  font-size: clamp(1.12rem, 2vw, 1.32rem);
  font-weight: 500;
  line-height: 1.4;
}

.page-about .tl-text {
  margin: 0;
  font-size: 0.95rem;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .tl-more {
  margin: 14px 0 0;
}

.page-about .tl-more a {
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(56, 242, 200, 0.35);
  padding-bottom: 2px;
  transition: border-color var(--dur) var(--ease);
}

.page-about .tl-more a:hover {
  border-bottom-color: var(--cyan);
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  gap: 16px;
}

.page-about .team-card {
  border: 2px solid var(--line-soft);
  border-radius: var(--radius-md);
  background: linear-gradient(180deg, var(--ink-3), var(--ink-2));
  padding: clamp(18px, 3vw, 28px);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .team-card:hover,
.page-about .team-card:focus-within {
  border-color: var(--cyan);
  transform: translateY(-3px);
  box-shadow: var(--shadow-2);
}

.page-about .team-num {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.22em;
  color: var(--amber);
}

.page-about .team-card h3 {
  margin: 0 0 10px;
  font-size: 1.18rem;
  font-weight: 500;
}

.page-about .team-text {
  margin: 0;
  font-size: 0.93rem;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-fold {
  margin-top: 18px;
  border-top: 1px solid var(--line-soft);
  padding-top: 10px;
}

.page-about .about-fold summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 6px 0;
  font-size: 13px;
  letter-spacing: 0.05em;
  color: var(--cyan);
}

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

.page-about .about-fold summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 16px;
  line-height: 1;
  color: var(--muted);
}

.page-about .about-fold[open] summary::after {
  content: "−";
  color: var(--cyan);
}

.page-about .fold-list {
  list-style: none;
  margin: 8px 0 0;
  padding: 0;
  display: grid;
  gap: 8px;
}

.page-about .fold-list li {
  position: relative;
  padding-left: 16px;
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--muted-dim);
}

.page-about .fold-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  border: 1.5px solid var(--line);
}

.page-about .team-note {
  margin: clamp(24px, 4vw, 38px) 0 0;
  max-width: 68ch;
  font-size: 0.95rem;
  line-height: 1.9;
  color: var(--muted-dim);
  border-left: 2px solid var(--line);
  padding-left: 16px;
}

/* ---------- 刷新节奏 ---------- */
.page-about .ruler {
  margin: 0 0 clamp(24px, 4vw, 40px);
  padding: clamp(16px, 3vw, 26px);
  border: 2px solid var(--line-soft);
  border-radius: var(--radius-md);
  background: var(--ink-2);
}

.page-about .ruler-svg {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .ruler-svg text {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  fill: var(--muted);
}

.page-about .ruler-svg .rail {
  stroke: var(--line);
  stroke-width: 2;
}

.page-about .ruler-svg .ticks line {
  stroke: var(--cyan);
  stroke-width: 2;
}

.page-about .ruler-svg .ticks--slow line {
  stroke: var(--amber);
  stroke-width: 2;
}

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

.page-about .rhythm-item {
  padding: 16px 0 0;
  border-top: 2px solid var(--line-soft);
}

.page-about .rhythm-item h3 {
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 500;
  letter-spacing: 0.02em;
}

.page-about .rhythm-item p {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.85;
  color: var(--muted);
}

/* ---------- 三条主张 ---------- */
.page-about .claims-box {
  position: relative;
  overflow: hidden;
  border: 2px solid var(--line);
  border-radius: 14px;
  padding: clamp(26px, 5vw, 54px);
  background: linear-gradient(155deg, rgba(11, 58, 46, 0.6), rgba(7, 18, 15, 0.25));
}

.page-about .claims-mark {
  position: absolute;
  top: -34px;
  right: clamp(8px, 4vw, 46px);
  margin: 0;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(120px, 22vw, 220px);
  line-height: 1;
  color: rgba(56, 242, 200, 0.09);
  pointer-events: none;
  user-select: none;
}

.page-about .claims-box .sec-num {
  position: relative;
  color: var(--amber);
}

.page-about .claims-quote {
  position: relative;
  margin: 0 0 clamp(22px, 4vw, 38px);
  max-width: 24ch;
  font-size: clamp(1.35rem, 3.6vw, 2.35rem);
  font-weight: 300;
  line-height: 1.4;
  letter-spacing: -0.01em;
}

.page-about .claim-list {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .claim {
  border-top: 1px solid var(--line-soft);
  padding: 18px 0 4px;
}

.page-about .claim h3 {
  margin: 0 0 8px;
  font-size: 1.02rem;
  font-weight: 500;
  color: var(--cyan);
}

.page-about .claim p {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.85;
  color: var(--muted);
}

/* ---------- 观察网络 ---------- */
.page-about .network-grid {
  display: grid;
  gap: clamp(22px, 4vw, 44px);
  align-items: center;
}

.page-about .network-lede {
  margin: 16px 0 0;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .network-text {
  margin: 14px 0 0;
  font-size: 0.95rem;
  line-height: 1.9;
  color: var(--muted-dim);
}

.page-about .network-list {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
  border-top: 1px solid var(--line-soft);
  padding-top: 18px;
}

.page-about .network-list li {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: 0.92rem;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .about-network-figure {
  margin: 0;
}

.page-about .about-network-figure img {
  width: 100%;
  aspect-ratio: 12 / 7;
  object-fit: cover;
}

/* ---------- 收束入口 ---------- */
.page-about .about-next {
  max-width: 960px;
  margin: 0 auto;
}

.page-about .next-lede {
  margin: 14px 0 clamp(22px, 4vw, 34px);
  font-size: 0.98rem;
  line-height: 1.85;
  color: var(--muted);
}

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

.page-about .next-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: clamp(18px, 3vw, 24px);
  border: 2px solid var(--line-soft);
  border-radius: var(--radius-md);
  background: var(--ink-2);
  color: inherit;
  text-decoration: none;
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .next-card:hover,
.page-about .next-card:focus-visible {
  border-color: var(--cyan);
  transform: translateY(-3px);
  box-shadow: var(--shadow-2);
}

.page-about .next-tag {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--amber);
}

.page-about .next-title {
  font-size: 1.06rem;
  font-weight: 500;
  line-height: 1.4;
}

.page-about .next-text {
  font-size: 0.9rem;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .next-foot {
  margin: clamp(24px, 4vw, 36px) 0 0;
  font-size: 0.9rem;
  line-height: 1.8;
  color: var(--muted-dim);
}

.page-about .next-foot a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(56, 242, 200, 0.35);
}

.page-about .next-foot a:hover {
  border-bottom-color: var(--cyan);
}

/* ---------- 响应式 ---------- */
@media (min-width: 620px) {
  .page-about .rhythm-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px 28px;
  }

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

@media (min-width: 880px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }

  .page-about .about-sec-head {
    grid-template-columns: minmax(0, 1fr) minmax(0, 300px);
  }

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

  .page-about .tl::before {
    left: 50%;
    transform: translateX(-1px);
  }

  .page-about .tl-item {
    width: 50%;
    padding-left: 0;
  }

  .page-about .tl-item:nth-child(odd) {
    padding-right: 54px;
  }

  .page-about .tl-item:nth-child(even) {
    margin-left: 50%;
    padding-left: 54px;
  }

  .page-about .tl-item:nth-child(odd) .tl-dot {
    left: auto;
    right: -9px;
  }

  .page-about .tl-item:nth-child(even) .tl-dot {
    left: -9px;
  }

  .page-about .team-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
    align-items: start;
  }

  .page-about .team-card:nth-child(2) {
    margin-top: 42px;
  }

  .page-about .team-card:nth-child(3) {
    margin-top: 84px;
  }

  .page-about .claim-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0 30px;
  }

  .page-about .claim {
    border-top: 2px solid var(--line);
  }

  .page-about .network-grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  }
}

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

  .page-about .tl-item:hover .tl-card,
  .page-about .team-card:hover,
  .page-about .next-card:hover {
    transform: none;
  }
}