.page-about {
  --about-rail: 236px;
  --about-gap: clamp(28px, 4vw, 60px);
  display: block;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-top: clamp(14px, 2vw, 22px);
  font-size: 0.82rem;
  color: var(--moss);
  letter-spacing: 0.02em;
}
.page-about .breadcrumbs a {
  color: var(--moss);
  text-decoration: none;
  transition: color var(--dur-fast) ease;
}
.page-about .breadcrumbs a:hover,
.page-about .breadcrumbs a:focus-visible {
  color: var(--cyan);
}
.page-about .breadcrumbs .crumb-sep {
  color: var(--line);
}
.page-about .breadcrumbs [aria-current="page"] {
  color: var(--mist);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  margin-top: clamp(14px, 2vw, 22px);
  padding: clamp(32px, 5vw, 72px) 0 clamp(26px, 3.6vw, 52px);
  background:
    radial-gradient(circle at 84% 8%, rgba(56, 242, 208, 0.13), transparent 56%),
    linear-gradient(168deg, var(--forest) 0%, var(--ink) 76%);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
}
.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(90deg, rgba(56, 242, 208, 0.055) 0 1px, transparent 1px 86px),
    repeating-linear-gradient(0deg, rgba(56, 242, 208, 0.035) 0 1px, transparent 1px 86px);
}
.page-about .about-hero-inner {
  position: relative;
  z-index: 1;
}
.page-about .about-hero .eyebrow {
  color: var(--cyan);
  letter-spacing: 0.18em;
  margin: 0 0 clamp(12px, 1.8vw, 20px);
}
.page-about .about-hero h1 {
  margin: 0 0 clamp(16px, 2.2vw, 26px);
  max-width: 17ch;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.1rem, 5.4vw, 4.4rem);
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--mist);
}
.page-about .about-lede {
  margin: 0;
  max-width: 62ch;
  font-size: clamp(0.96rem, 1.3vw, 1.08rem);
  line-height: 1.85;
  color: rgba(232, 244, 239, 0.82);
}
.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px 18px;
  margin: clamp(24px, 3.2vw, 38px) 0 0;
  padding: clamp(16px, 2vw, 24px) 0 0;
  border-top: 1px solid var(--line);
}
.page-about .about-facts div {
  min-width: 0;
}
.page-about .about-facts dt {
  margin: 0 0 5px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.14em;
  color: var(--moss);
}
.page-about .about-facts dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(1.15rem, 2vw, 1.5rem);
  font-weight: 600;
  color: var(--mist);
  letter-spacing: -0.01em;
}
.page-about .about-facts dd span {
  margin-left: 4px;
  font-size: 0.68rem;
  font-weight: 400;
  color: var(--moss);
}

/* ---------- 主体双栏 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  padding-block: clamp(34px, 4.4vw, 70px);
}

/* ---------- 左栏索引 ---------- */
.page-about .about-rail {
  min-width: 0;
  padding: 16px 16px 18px;
  background: var(--forest);
  border: 1px solid var(--line);
  border-radius: var(--r-l);
}
.page-about .rail-label {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.16em;
  color: var(--cyan);
}
.page-about .rail-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 2px;
}
.page-about .rail-list a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 8px 10px;
  border-left: 2px solid transparent;
  border-radius: var(--r-s);
  font-size: 0.88rem;
  line-height: 1.5;
  color: var(--moss);
  text-decoration: none;
  transition: color var(--dur-fast) ease, background var(--dur-fast) ease, border-color var(--dur-fast) ease;
}
.page-about .rail-list a:hover,
.page-about .rail-list a:focus-visible {
  color: var(--mist);
  background: rgba(56, 242, 208, 0.07);
  border-left-color: var(--cyan);
}
.page-about .rail-num {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--line);
}
.page-about .rail-list a:hover .rail-num,
.page-about .rail-list a:focus-visible .rail-num {
  color: var(--cyan);
}
.page-about .rail-note {
  margin: 16px 0 0;
  padding-top: 14px;
  border-top: 1px solid var(--line);
  font-size: 0.78rem;
  line-height: 1.75;
  color: var(--moss);
}

/* ---------- 右侧内容流 ---------- */
.page-about .about-flow {
  min-width: 0;
}
.page-about .about-section {
  padding-block: clamp(28px, 3.6vw, 54px);
  border-top: 1px solid var(--line);
}
.page-about .about-section:first-child {
  border-top: 0;
  padding-top: 0;
}
.page-about .about-section .section-head {
  margin-bottom: clamp(16px, 2.2vw, 26px);
}
.page-about .about-section .eyebrow {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  color: var(--moss);
  margin: 0 0 10px;
}
.page-about .about-section h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.45rem, 2.8vw, 2.25rem);
  line-height: 1.22;
  letter-spacing: -0.015em;
  color: var(--mist);
}
.page-about .about-section-lede {
  margin: 0 0 clamp(18px, 2.4vw, 28px);
  max-width: 64ch;
  font-size: 0.96rem;
  line-height: 1.8;
  color: rgba(232, 244, 239, 0.74);
}
.page-about .prose p {
  margin: 0 0 1.05em;
  max-width: 66ch;
  font-size: 0.97rem;
  line-height: 1.82;
  color: rgba(232, 244, 239, 0.84);
}
.page-about .prose p:last-child {
  margin-bottom: 0;
}

/* ---------- 分栏与图 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 2.8vw, 34px);
  align-items: start;
}
.page-about .about-figure,
.page-about .about-wide-figure {
  margin: 0;
  min-width: 0;
}
.page-about .about-figure img,
.page-about .about-wide-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border-radius: var(--r-m);
  background: var(--forest-lift);
}
.page-about .about-figure img {
  aspect-ratio: 4 / 5;
}
.page-about .about-wide-figure {
  margin-top: clamp(20px, 2.6vw, 32px);
}
.page-about .about-wide-figure img {
  aspect-ratio: 12 / 5;
}
.page-about .media-caption {
  margin: 10px 0 0;
  font-size: 0.76rem;
  line-height: 1.7;
  color: var(--moss);
}

/* ---------- 引文块 ---------- */
.page-about .pull {
  margin: clamp(20px, 2.6vw, 30px) 0;
  padding: clamp(18px, 2.4vw, 26px) clamp(18px, 2.6vw, 30px);
  background: linear-gradient(120deg, var(--forest), var(--forest-lift));
  border-left: 3px solid var(--cyan);
  border-radius: 0 var(--r-m) var(--r-m) 0;
}
.page-about .pull p {
  margin: 0 0 12px;
  max-width: 34ch;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.05rem, 1.8vw, 1.32rem);
  line-height: 1.55;
  color: var(--mist);
}
.page-about .pull cite {
  font-style: normal;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--moss);
}

/* ---------- 角色卡 ---------- */
.page-about .role-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: clamp(18px, 2.4vw, 26px);
}
.page-about .role-card {
  position: relative;
  padding: 20px 20px 22px;
  background: var(--forest-lift);
  border: 1px solid var(--line);
  border-radius: var(--r-l);
  overflow: hidden;
  transition: transform var(--dur) ease, border-color var(--dur) ease, box-shadow var(--dur) ease;
}
.page-about .role-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--cyan);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--dur) ease;
}
.page-about .role-card:hover,
.page-about .role-card:focus-within {
  transform: translateY(-3px);
  border-color: rgba(56, 242, 208, 0.45);
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.32);
}
.page-about .role-card:hover::before,
.page-about .role-card:focus-within::before {
  transform: scaleX(1);
}
.page-about .role-num {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: clamp(1.55rem, 2.6vw, 2rem);
  font-weight: 600;
  line-height: 1;
  color: var(--cyan);
  letter-spacing: -0.02em;
}
.page-about .role-card h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1rem;
  letter-spacing: 0.01em;
  color: var(--mist);
}
.page-about .role-duty {
  margin: 0;
  font-size: 0.86rem;
  line-height: 1.75;
  color: var(--moss);
  opacity: 0.8;
  transition: opacity var(--dur) ease, color var(--dur) ease;
}
.page-about .role-card:hover .role-duty,
.page-about .role-card:focus-within .role-duty {
  opacity: 1;
  color: rgba(232, 244, 239, 0.9);
}

/* ---------- 流程折叠 ---------- */
.page-about .flow {
  display: grid;
  gap: 10px;
}
.page-about .flow-step {
  background: var(--forest);
  border: 1px solid var(--line);
  border-radius: var(--r-l);
  overflow: hidden;
  transition: border-color var(--dur) ease, background var(--dur) ease;
}
.page-about .flow-step[open] {
  border-color: rgba(56, 242, 208, 0.38);
  background: var(--forest-lift);
}
.page-about .flow-step summary {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 0.98rem;
  color: var(--mist);
  transition: background var(--dur-fast) ease;
}
.page-about .flow-step summary::-webkit-details-marker {
  display: none;
}
.page-about .flow-step summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-weight: 400;
  font-size: 1.1rem;
  color: var(--cyan);
}
.page-about .flow-step[open] summary::after {
  content: "–";
}
.page-about .flow-step summary:hover {
  background: rgba(56, 242, 208, 0.06);
}
.page-about .flow-step summary:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: -2px;
}
.page-about .flow-index {
  flex: none;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--cyan);
}
.page-about .flow-title {
  min-width: 0;
}
.page-about .flow-body {
  padding: 0 18px 18px;
}
.page-about .flow-body p {
  margin: 0 0 10px;
  max-width: 64ch;
  font-size: 0.9rem;
  line-height: 1.8;
  color: rgba(232, 244, 239, 0.8);
}
.page-about .flow-body p:last-child {
  margin-bottom: 0;
}
.page-about .flow-body .meta {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.04em;
  color: var(--moss);
}

/* ---------- 时间线 ---------- */
.page-about .timeline {
  margin: 0;
  padding: 0;
  list-style: none;
}
.page-about .tl-item {
  position: relative;
  padding-left: 26px;
  padding-bottom: 6px;
}
.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 16px;
  bottom: -2px;
  width: 1px;
  background: linear-gradient(var(--line), rgba(31, 90, 78, 0.15));
}
.page-about .tl-item:last-child::before {
  display: none;
}
.page-about .tl-node summary {
  position: relative;
  display: block;
  padding: 4px 0 12px;
  cursor: pointer;
  list-style: none;
}
.page-about .tl-node summary::-webkit-details-marker {
  display: none;
}
.page-about .tl-node summary::before {
  content: "";
  position: absolute;
  left: -27px;
  top: 11px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--ink);
  border: 2px solid var(--line);
  transition: border-color var(--dur) ease, box-shadow var(--dur) ease;
}
.page-about .tl-node[open] summary::before {
  border-color: var(--cyan);
  box-shadow: 0 0 0 4px rgba(56, 242, 208, 0.14);
}
.page-about .tl-node summary:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 4px;
  border-radius: var(--r-s);
}
.page-about .tl-year {
  display: inline-block;
  margin-right: 12px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--cyan);
}
.page-about .tl-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(0.98rem, 1.5vw, 1.12rem);
  color: var(--mist);
}
.page-about .tl-body {
  padding: 0 0 14px;
}
.page-about .tl-body p {
  margin: 0;
  max-width: 62ch;
  font-size: 0.9rem;
  line-height: 1.8;
  color: rgba(232, 244, 239, 0.78);
}

/* ---------- 规模网格 ---------- */
.page-about .scale-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: clamp(18px, 2.4vw, 26px);
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--r-l);
  overflow: hidden;
}
.page-about .scale-cell {
  padding: 18px 16px;
  background: var(--forest);
  min-width: 0;
  transition: background var(--dur-fast) ease;
}
.page-about .scale-cell:hover {
  background: var(--forest-lift);
}
.page-about .scale-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.1rem, 2.1vw, 1.6rem);
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--mist);
  word-break: break-word;
}
.page-about .scale-label {
  display: block;
  margin-top: 6px;
  font-size: 0.76rem;
  line-height: 1.6;
  color: var(--moss);
}
.page-about .about-footnote {
  margin: clamp(18px, 2.4vw, 26px) 0 0;
  max-width: 64ch;
  font-size: 0.88rem;
  line-height: 1.8;
  color: rgba(232, 244, 239, 0.7);
}

/* ---------- 联系 ---------- */
.page-about .contact-panel {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 2.8vw, 34px);
  margin-top: clamp(16px, 2.2vw, 22px);
  padding: clamp(22px, 3vw, 38px);
  background:
    radial-gradient(circle at 92% 4%, rgba(56, 242, 208, 0.1), transparent 58%),
    linear-gradient(150deg, var(--forest), var(--ink));
  border: 1px solid var(--line);
  border-radius: var(--r-xl);
}
.page-about .contact-copy p {
  margin: 0 0 1em;
  max-width: 56ch;
  font-size: 0.94rem;
  line-height: 1.82;
  color: rgba(232, 244, 239, 0.82);
}
.page-about .contact-copy p:last-child {
  margin-bottom: 0;
}
.page-about .contact-list {
  margin: 0;
  display: grid;
  gap: 14px;
  align-content: start;
}
.page-about .contact-list div {
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line);
  min-width: 0;
}
.page-about .contact-list div:last-child {
  padding-bottom: 0;
  border-bottom: 0;
}
.page-about .contact-list dt {
  margin: 0 0 4px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  color: var(--moss);
}
.page-about .contact-list dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  line-height: 1.6;
  color: var(--mist);
  word-break: break-word;
}

/* ---------- 按钮组 ---------- */
.page-about .about-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: clamp(20px, 2.6vw, 30px);
}

/* ---------- 平板与桌面 ---------- */
@media (min-width: 720px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .about-split {
    grid-template-columns: minmax(0, 1fr) minmax(200px, 0.54fr);
  }
  .page-about .role-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .scale-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 960px) {
  .page-about .about-body {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    align-items: start;
  }
  .page-about .about-rail {
    position: sticky;
    top: 104px;
    align-self: start;
  }
  .page-about .contact-panel {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
  }
}

@media (min-width: 1180px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 1fr) minmax(240px, 0.5fr);
    gap: clamp(28px, 3.4vw, 48px);
  }
  .page-about .prose p {
    font-size: 1rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .role-card,
  .page-about .role-card::before,
  .page-about .role-duty,
  .page-about .tl-node summary::before,
  .page-about .rail-list a,
  .page-about .scale-cell {
    transition: opacity var(--dur-fast) ease;
  }
  .page-about .role-card:hover,
  .page-about .role-card:focus-within {
    transform: none;
  }
  .page-about .role-card:hover::before,
  .page-about .role-card:focus-within::before {
    transform: scaleX(1);
  }
}