.page-about {
  --about-side-w: 220px;
  background: var(--ink);
  color: var(--mist);
}

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

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: 28px 0 48px;
  border-bottom: 1px solid var(--line);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: -10%;
  bottom: -70%;
  width: 70%;
  height: 340px;
  background: radial-gradient(60% 100% at 50% 0%, rgba(53, 208, 196, .16), transparent 72%);
  pointer-events: none;
}

.page-about .about-hero__grid {
  position: relative;
  display: grid;
  gap: 28px;
}

.page-about .about-hero__lead {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.page-about h1 {
  margin: 0;
  font-family: var(--serif);
  font-weight: 700;
  font-size: clamp(30px, 7vw, 52px);
  line-height: 1.15;
  letter-spacing: -0.01em;
  color: var(--mist);
}

.page-about .lede {
  margin: 0;
  max-width: 58ch;
  font-size: 17px;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin: 6px 0 0;
  padding: 16px 0 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.page-about .about-facts li {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.page-about .about-facts .num {
  font-family: var(--mono);
  font-size: 22px;
  line-height: 1.2;
  color: var(--amber);
}

.page-about .about-facts__label {
  font-size: 13px;
  color: var(--muted);
}

.page-about .about-hero__media {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--indigo);
}

.page-about .about-hero__media img {
  width: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .about-hero__media figcaption {
  padding: 10px 14px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 主体骨架：左索引 + 右侧纵向叙事 ---------- */
.page-about .about-body {
  padding: 34px 0 72px;
}

.page-about .about-layout {
  display: grid;
  gap: 34px;
}

.page-about .about-side__title {
  margin: 0 0 10px;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--muted);
}

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

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

.page-about .about-nav a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: 1px solid var(--line);
  background: rgba(18, 40, 62, .6);
  color: var(--mist);
  font-size: 14px;
  line-height: 1.3;
  text-decoration: none;
  white-space: nowrap;
  transition: border-color .16s var(--ease), color .16s var(--ease), background-color .16s var(--ease);
}

.page-about .about-nav a .mono {
  font-size: 12px;
  color: var(--amber);
}

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

.page-about .about-side__foot {
  display: none;
  margin-top: 18px;
}

.page-about .about-flow {
  min-width: 0;
}

/* ---------- 章节 ---------- */
.page-about .about-chapter {
  padding: 40px 0;
  border-top: 1px solid var(--line);
}

.page-about .about-chapter:first-child {
  padding-top: 8px;
  border-top: 0;
}

.page-about .about-chapter--band {
  margin: 8px 0;
  padding: 28px 20px;
  border: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(23, 52, 80, .92), rgba(18, 40, 62, .72));
}

.page-about .about-chapter__head {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 22px;
}

.page-about .about-chapter h2 {
  margin: 0;
  font-family: var(--serif);
  font-weight: 700;
  font-size: clamp(23px, 4.4vw, 34px);
  line-height: 1.22;
  color: var(--mist);
}

.page-about .about-prose p,
.page-about .prose p {
  margin: 0 0 1.15em;
  max-width: 66ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .about-prose p:last-child,
.page-about .prose p:last-child {
  margin-bottom: 0;
}

.page-about .tag-flow {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-quote {
  margin: 22px 0 0;
  padding: 20px 22px;
  border-left: 3px solid var(--amber);
  background: var(--ivory);
  color: var(--ink);
}

.page-about .about-quote p {
  margin: 0;
  max-width: 60ch;
  font-family: var(--serif);
  font-size: 17px;
  line-height: 1.7;
}

/* ---------- 时间轴 ---------- */
.page-about .about-track {
  position: relative;
  margin-top: 8px;
}

.page-about .about-track::before {
  content: "";
  position: absolute;
  left: 14px;
  top: 12px;
  bottom: 12px;
  width: 1px;
  background: linear-gradient(180deg, var(--line), rgba(36, 66, 92, .25));
}

.page-about .stage {
  position: relative;
  display: grid;
  grid-template-columns: 30px minmax(0, 1fr);
  margin-bottom: 20px;
}

.page-about .stage:last-child {
  margin-bottom: 0;
}

.page-about .stage__node {
  grid-column: 1;
  justify-self: center;
  width: 15px;
  height: 15px;
  margin-top: 24px;
  border: 1px solid var(--line);
  border-radius: 50%;
  background: var(--ink);
  z-index: 1;
  transition: transform .16s var(--ease), border-color .16s var(--ease), box-shadow .16s var(--ease);
}

.page-about .stage:hover .stage__node,
.page-about .stage:focus-within .stage__node,
.page-about .stage:target .stage__node {
  transform: scale(1.1);
  border-color: var(--cyan);
  box-shadow: 0 0 0 4px rgba(53, 208, 196, .14);
}

.page-about .stage__card {
  grid-column: 2;
  min-width: 0;
  padding: 18px 18px 20px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--line);
  background: var(--indigo);
  transition: border-color .16s var(--ease), transform .16s var(--ease), box-shadow .16s var(--ease);
}

.page-about .stage:hover .stage__card {
  transform: translateY(-1px);
  box-shadow: 0 12px 26px rgba(0, 0, 0, .3);
}

.page-about .stage:target .stage__card {
  border-color: var(--cyan);
  border-left-color: var(--cyan);
}

.page-about .stage--wine .stage__card { border-left-color: var(--wine); }
.page-about .stage--violet .stage__card { border-left-color: var(--violet); }
.page-about .stage--pine .stage__card { border-left-color: var(--pine); }
.page-about .stage--ochre .stage__card { border-left-color: var(--ochre); }
.page-about .stage--amber .stage__card { border-left-color: var(--amber); }

.page-about .stage__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: 10px;
}

.page-about .stage__year {
  font-size: 15px;
  letter-spacing: 0.04em;
  color: var(--amber);
}

.page-about .stage__batch {
  padding: 2px 8px;
  border: 1px solid var(--line);
  font-size: 12px;
  color: var(--muted);
}

.page-about .stage__card h3 {
  margin: 0 0 8px;
  font-family: var(--geo);
  font-weight: 700;
  font-size: 18px;
  line-height: 1.4;
  color: var(--mist);
}

.page-about .stage__card > p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .stage__hint {
  display: grid;
  grid-template-rows: 1fr;
  margin-top: 14px;
}

.page-about .stage__hint > span {
  display: block;
  min-height: 0;
  overflow: hidden;
  padding: 0 0 0 10px;
  border-left: 2px solid var(--amber);
  font-size: 13.5px;
  line-height: 1.65;
  color: var(--amber);
}

.page-about .stage-more {
  margin-top: 14px;
  padding-top: 10px;
  border-top: 1px dashed var(--line);
}

.page-about .stage-more summary {
  display: flex;
  align-items: center;
  gap: 6px;
  list-style: none;
  cursor: pointer;
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--cyan);
}

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

.page-about .stage-more summary::before {
  content: "+";
  font-size: 15px;
  line-height: 1;
}

.page-about .stage-more[open] summary::before {
  content: "–";
}

.page-about .stage-more__body {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-top: 10px;
  font-size: 14px;
  line-height: 1.72;
  color: var(--muted);
}

.page-about .stage-more__body p {
  margin: 0;
}

.page-about .stage-more__body strong {
  color: var(--mist);
  font-weight: 600;
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  display: grid;
  gap: 22px;
}

.page-about .about-team__media {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--indigo);
}

.page-about .about-team__media img {
  width: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .about-team__media figcaption {
  padding: 10px 14px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .team-list {
  display: grid;
  gap: 1px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
  border: 1px solid var(--line);
  background: var(--line);
}

.page-about .team-list li {
  display: grid;
  grid-template-columns: 3.2rem minmax(0, 1fr);
  gap: 4px 12px;
  padding: 14px 16px;
  background: var(--ink);
}

.page-about .team-list .num {
  grid-row: span 2;
  align-self: start;
  font-family: var(--mono);
  font-size: 22px;
  line-height: 1.2;
  color: var(--cyan);
}

.page-about .team-list__name {
  font-family: var(--geo);
  font-weight: 700;
  font-size: 15px;
  color: var(--mist);
}

.page-about .team-list__desc {
  font-size: 13.5px;
  line-height: 1.65;
  color: var(--muted);
}

.page-about .team-list__note {
  margin: 12px 0 0;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 资质与合作 ---------- */
.page-about .about-credits {
  display: grid;
  gap: 22px;
}

.page-about .about-credits__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 18px 0 0;
}

.page-about .credit-cards {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  border: 1px solid var(--line);
  background: var(--line);
}

.page-about .credit-card {
  padding: 16px;
  background: var(--card);
}

.page-about .credit-card .num {
  display: block;
  font-family: var(--mono);
  font-size: 26px;
  line-height: 1.15;
  color: var(--amber);
}

.page-about .credit-card p {
  margin: 8px 0 0;
  font-size: 13.5px;
  line-height: 1.65;
  color: var(--muted);
}

/* ---------- 服务网络 ---------- */
.page-about .about-network {
  display: grid;
  gap: 22px;
}

.page-about .network-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 28px;
  margin: 20px 0 0;
}

.page-about .network-stat {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding-left: 14px;
  border-left: 2px solid var(--cyan);
}

.page-about .network-stat .num {
  font-family: var(--mono);
  font-size: 38px;
  line-height: 1.1;
  color: var(--cyan);
}

.page-about .network-stat span:last-child {
  font-size: 13px;
  color: var(--muted);
}

.page-about .about-network__link {
  margin: 18px 0 0;
}

.page-about .about-network__media {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--indigo);
}

.page-about .about-network__media img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.page-about .about-network__media figcaption {
  padding: 10px 14px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 长期合作 ---------- */
.page-about .about-trust {
  display: grid;
  gap: 20px;
}

.page-about .trust-figure {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 20px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--amber);
  background: var(--indigo);
}

.page-about .trust-figure .num {
  font-family: var(--mono);
  font-size: 44px;
  line-height: 1;
  color: var(--amber);
}

.page-about .trust-figure__label {
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .about-trust__link {
  margin: 16px 0 0;
}

.page-about a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 208, 196, .35);
  transition: border-color .16s var(--ease), color .16s var(--ease);
}

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

.page-about .btn {
  border-bottom: 0;
}

/* ---------- 下一步 ---------- */
.page-about .about-cta {
  padding: 48px 0 56px;
  border-top: 1px solid var(--line);
  background: var(--indigo);
}

.page-about .about-cta__head {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 26px;
}

.page-about .about-cta h2 {
  margin: 0;
  font-family: var(--serif);
  font-weight: 700;
  font-size: clamp(22px, 4.2vw, 32px);
  line-height: 1.25;
  color: var(--mist);
}

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

.page-about .cta-card {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 20px;
  border: 1px solid var(--line);
  background: var(--ink);
  text-decoration: none;
  transition: border-color .16s var(--ease), transform .16s var(--ease);
}

.page-about .cta-card:hover,
.page-about .cta-card:focus-visible {
  border-color: var(--cyan);
  transform: translateY(-1px);
}

.page-about .cta-card h3 {
  margin: 0;
  font-family: var(--geo);
  font-weight: 700;
  font-size: 17px;
  color: var(--mist);
}

.page-about .cta-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .cta-card__go {
  margin-top: auto;
  padding-top: 6px;
  font-size: 12px;
  letter-spacing: 0.02em;
  color: var(--cyan);
}

/* ---------- 响应式 ---------- */
@media (min-width: 700px) {
  .page-about .about-hero {
    padding: 36px 0 56px;
  }

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

  .page-about .about-chapter {
    padding: 48px 0;
  }

  .page-about .about-chapter--band {
    padding: 34px 28px;
  }

  .page-about .stage__card {
    padding: 22px 24px 24px;
  }

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

@media (min-width: 880px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.06fr) minmax(0, .94fr);
    align-items: end;
    gap: 44px;
  }

  .page-about .about-team {
    grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr);
    gap: 32px;
    align-items: start;
  }

  .page-about .about-credits {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
    gap: 36px;
    align-items: start;
  }

  .page-about .about-network {
    grid-template-columns: minmax(0, 1.02fr) minmax(0, .98fr);
    gap: 34px;
    align-items: center;
  }

  .page-about .about-trust {
    grid-template-columns: 220px minmax(0, 1fr);
    gap: 34px;
    align-items: start;
  }
}

@media (min-width: 1000px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-side-w) minmax(0, 1fr);
    gap: 56px;
  }

  .page-about .about-side__inner {
    position: sticky;
    top: 96px;
  }

  .page-about .about-nav {
    flex-direction: column;
    gap: 2px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-nav li {
    width: 100%;
  }

  .page-about .about-nav a {
    display: flex;
    width: 100%;
    padding: 10px 12px;
    border: 0;
    border-left: 2px solid var(--line);
    background: none;
  }

  .page-about .about-nav a:hover,
  .page-about .about-nav a:focus-visible {
    border-left-color: var(--cyan);
    background: rgba(53, 208, 196, .07);
  }

  .page-about .about-side {
    display: block;
  }

  .page-about .about-side__foot {
    display: block;
  }

  .page-about .about-chapter:first-child {
    padding-top: 0;
  }
}

@media (hover: hover) and (pointer: fine) {
  .page-about .stage__hint {
    grid-template-rows: 0fr;
    transition: grid-template-rows .2s var(--ease);
  }

  .page-about .stage:hover .stage__hint,
  .page-about .stage:focus-within .stage__hint {
    grid-template-rows: 1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    transition: none !important;
    animation: none !important;
  }
}