.page-about {
  background: var(--ink-blue);
  color: var(--text-soft);
  font-family: var(--font-sans);
  overflow-x: clip;
}

.page-about h1,
.page-about h2,
.page-about h3 {
  color: var(--paper);
  font-weight: 800;
  letter-spacing: .04em;
  line-height: 1.22;
  margin: 0;
}

.page-about h1 { font-size: clamp(1.75rem, 5.2vw, 2.75rem); }
.page-about h2 { font-size: clamp(1.375rem, 3.6vw, 1.875rem); }
.page-about h3 { font-size: clamp(1.0625rem, 2.4vw, 1.1875rem); }

.page-about p { margin: 0; }

.page-about .kicker {
  font-family: var(--font-serif);
  font-size: .8125rem;
  letter-spacing: .24em;
  color: var(--gold);
  margin: 0 0 .9rem;
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb-wrap { padding-top: 1.5rem; }

.page-about .breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .5rem;
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: .8125rem;
  color: var(--steel);
}

.page-about .breadcrumb-list a {
  color: var(--snow);
  text-decoration: none;
  transition: color .2s var(--ease);
}

.page-about .breadcrumb-list a:hover { color: var(--teal); }

.page-about .breadcrumb-list li + li::before {
  content: "/";
  margin-right: .5rem;
  color: var(--steel);
}

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

/* ---------- 首屏 ---------- */
.about-hero {
  position: relative;
  overflow: hidden;
  isolation: isolate;
  padding: 2rem 0 3rem;
}

.about-hero::before {
  content: "";
  position: absolute;
  top: -7rem;
  left: 26%;
  right: -14%;
  height: 24rem;
  background: linear-gradient(112deg, rgba(168, 216, 232, .16), rgba(217, 164, 65, .12) 56%, rgba(18, 179, 154, .09));
  transform: skewY(-6deg);
  transform-origin: left top;
  pointer-events: none;
  z-index: -1;
}

.about-hero-grid {
  display: grid;
  gap: 2.25rem;
}

.about-lede {
  margin-top: 1.15rem;
  font-size: 1.0625rem;
  line-height: 1.85;
  color: var(--text-soft);
  max-width: 36em;
}

.about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line-dark);
  border: 1px solid var(--line-dark);
  border-radius: var(--radius-card);
  overflow: hidden;
  margin-top: 2rem;
}

.about-fact {
  background: var(--ink-night);
  padding: .9rem 1rem 1rem;
  display: flex;
  flex-direction: column;
  gap: .3rem;
  min-width: 0;
}

.about-fact-num {
  font-family: var(--font-mono);
  font-size: 1.375rem;
  letter-spacing: .02em;
  color: var(--gold);
  line-height: 1.1;
}

.about-fact-label {
  font-size: .75rem;
  line-height: 1.55;
  color: var(--steel);
}

/* ---------- 侧栏目录 ---------- */
.about-hero-side {
  border-top: 1px solid var(--line-dark);
  padding-top: 1.35rem;
}

.about-side-title {
  font-family: var(--font-serif);
  font-size: .8125rem;
  letter-spacing: .2em;
  color: var(--snow);
  margin: 0 0 1rem;
}

.about-toc {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: .125rem;
}

.about-toc a {
  display: flex;
  align-items: baseline;
  gap: .7rem;
  padding: .58rem .8rem;
  border-left: 2px solid transparent;
  border-radius: 0 var(--radius-card) var(--radius-card) 0;
  color: var(--text-soft);
  text-decoration: none;
  font-size: .9375rem;
  line-height: 1.5;
  transition: color .2s var(--ease), background .2s var(--ease), border-color .2s var(--ease);
}

.about-toc .toc-num {
  font-family: var(--font-mono);
  font-size: .6875rem;
  color: var(--steel);
  transition: color .2s var(--ease);
}

.about-toc a:hover {
  color: var(--paper);
  background: rgba(168, 216, 232, .07);
}

.about-toc a:hover .toc-num { color: var(--gold); }

.about-toc a[aria-current="true"] {
  color: var(--teal);
  border-left-color: var(--teal);
  background: rgba(18, 179, 154, .08);
}

.about-toc a[aria-current="true"] .toc-num { color: var(--teal); }

/* ---------- 章节骨架 ---------- */
.about-chapter {
  position: relative;
  padding: 3rem 0;
  border-top: 1px solid var(--line-dark);
}

.about-chapter-grid {
  display: grid;
  gap: 1.35rem;
}

.about-chapter-rail {
  display: flex;
  align-items: baseline;
  gap: .75rem;
}

.about-chapter-num {
  font-family: var(--font-mono);
  font-size: 1.375rem;
  letter-spacing: .06em;
  color: var(--gold);
  line-height: 1;
}

.about-chapter-label {
  font-family: var(--font-serif);
  font-size: .8125rem;
  letter-spacing: .2em;
  color: var(--steel);
  margin: 0;
}

.about-chapter-body p {
  margin-top: 1rem;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--text-soft);
  max-width: 38em;
}

.about-chapter-lead {
  font-family: var(--font-serif);
  color: var(--snow) !important;
}

/* ---------- 第二节：主张 ---------- */
.about-principles { overflow: hidden; }

.about-principles-bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: .34;
  pointer-events: none;
  z-index: 0;
}

.about-principles::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(14, 27, 51, .82), rgba(22, 35, 63, .92));
  pointer-events: none;
  z-index: 0;
}

.about-principles .shell {
  position: relative;
  z-index: 1;
}

.claim-stack {
  display: grid;
  gap: 1rem;
  margin-top: 1.9rem;
}

.claim-card {
  position: relative;
  background: var(--paper);
  color: var(--ink-brown);
  border: 1px solid var(--sand);
  border-radius: var(--radius-card);
  padding: 1.35rem 1.2rem 1.25rem;
  box-shadow: 4px 4px 0 rgba(201, 194, 180, .16), 8px 8px 0 rgba(201, 194, 180, .07);
  transition: transform .22s var(--ease), box-shadow .22s var(--ease);
}

.claim-card:hover {
  transform: translateY(-4px);
  box-shadow: 6px 8px 0 rgba(217, 164, 65, .26), 11px 15px 0 rgba(201, 194, 180, .08);
}

.claim-index {
  font-family: var(--font-mono);
  font-size: .75rem;
  letter-spacing: .14em;
  color: var(--gold-ink);
  margin: 0 0 .55rem;
}

.page-about .claim-card h3 {
  color: var(--ink-brown);
  font-size: 1.125rem;
  letter-spacing: .03em;
  margin: 0 0 .6rem;
}

.claim-card > p {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.78;
  color: rgba(36, 28, 24, .82);
  max-width: none;
}

.claim-scene {
  margin-top: .85rem !important;
  padding: .7rem .85rem;
  background: rgba(217, 164, 65, .15);
  border-left: 2px solid var(--gold);
  border-radius: 0 4px 4px 0;
  font-size: .875rem !important;
  line-height: 1.72 !important;
  color: rgba(36, 28, 24, .86) !important;
  transition: max-height .28s var(--ease), opacity .24s var(--ease), margin-top .24s var(--ease), padding .24s var(--ease);
}

/* ---------- 第三节：节点（纸面区段） ---------- */
.page-about .about-milestones {
  background: var(--paper);
  color: var(--ink-brown);
  border-top-color: var(--sand);
}

.page-about .about-milestones h2 { color: var(--ink-brown); }
.page-about .about-milestones h3 { color: var(--ink-brown); }

.about-chapter-rail--dark .about-chapter-num { color: var(--gold-ink); }

.page-about .about-milestones .about-chapter-label { color: var(--gold-ink); }
.page-about .about-milestones .about-chapter-lead { color: rgba(36, 28, 24, .74) !important; }

.milestones-figure {
  margin: 1.75rem 0 0;
  border: 1px solid var(--sand);
  border-radius: var(--radius-card);
  overflow: hidden;
  background: var(--ink-night);
}

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

.milestone-scale {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  list-style: none;
  margin: 2rem 0 0;
  padding: 0;
  border-top: 1px solid var(--sand);
}

.milestone-scale li { position: relative; min-width: 0; }

.milestone-scale a {
  position: relative;
  display: block;
  padding: 1.15rem .35rem .8rem;
  font-family: var(--font-mono);
  font-size: .875rem;
  letter-spacing: .04em;
  color: var(--gold-ink);
  text-decoration: none;
  transition: color .2s var(--ease);
}

.milestone-scale a::before {
  content: "";
  position: absolute;
  top: -5px;
  left: .35rem;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--paper);
  border: 2px solid var(--gold);
  transition: background .2s var(--ease), border-color .2s var(--ease), transform .2s var(--ease);
}

.milestone-scale a:hover { color: var(--ink-brown); }

.milestone-scale a:hover::before {
  background: var(--teal);
  border-color: var(--teal);
  transform: scale(1.22);
}

.milestone-list {
  margin-top: .5rem;
  display: grid;
}

.milestone {
  display: grid;
  gap: .4rem;
  padding: 1.3rem 0;
  border-bottom: 1px dashed var(--sand);
  scroll-margin-top: 6rem;
}

.milestone:last-child { border-bottom: 0; padding-bottom: 0; }

.milestone-year {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  letter-spacing: .04em;
  color: var(--gold-ink);
  margin: 0;
  line-height: 1.1;
}

.milestone-content h3 {
  font-size: 1.0625rem;
  letter-spacing: .03em;
  margin: 0 0 .45rem;
}

.page-about .milestone-content p {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.78;
  color: rgba(36, 28, 24, .78);
  max-width: 40em;
}

/* ---------- 第四节：团队 ---------- */
.team-layout {
  display: grid;
  gap: 1.75rem;
  margin-top: 1.8rem;
}

.team-grid {
  display: grid;
  gap: 1rem;
}

.team-card {
  background: var(--ink-night);
  border: 1px solid var(--line-dark);
  border-top: 3px solid var(--gold);
  border-radius: 0 0 var(--radius-card) var(--radius-card);
  padding: 1.15rem 1.1rem 1.25rem;
  min-width: 0;
}

.page-about .team-card h3 {
  font-size: 1rem;
  letter-spacing: .04em;
  color: var(--snow);
  margin: 0 0 .5rem;
}

.page-about .team-card p {
  margin: 0;
  font-size: .875rem;
  line-height: 1.78;
  color: var(--text-soft);
  max-width: none;
}

.team-figure {
  margin: 0;
}

.team-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border-radius: var(--radius-card);
  border: 1px solid var(--line-dark);
}

.team-figure figcaption {
  margin-top: .65rem;
  font-size: .75rem;
  line-height: 1.65;
  color: var(--steel);
}

/* ---------- 第五节：地区 ---------- */
.region-grid {
  display: grid;
  gap: 1px;
  background: var(--line-dark);
  border: 1px solid var(--line-dark);
  border-radius: var(--radius-card);
  overflow: hidden;
  margin-top: 1.8rem;
}

.region-item {
  background: var(--ink-night);
  padding: 1.2rem 1.1rem 1.3rem;
  min-width: 0;
}

.page-about .region-item h3 {
  font-size: .9375rem;
  letter-spacing: .06em;
  color: var(--snow);
  margin: 0 0 .5rem;
}

.page-about .region-item p {
  margin: 0;
  font-size: .875rem;
  line-height: 1.78;
  color: var(--text-soft);
  max-width: none;
}

.region-meta {
  margin-top: 1.6rem;
  padding: 1.15rem 1.15rem 1.25rem;
  background: rgba(168, 216, 232, .06);
  border-left: 3px solid var(--gold);
  border-radius: 0 var(--radius-card) var(--radius-card) 0;
}

.region-meta-line {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: .6rem;
  margin: 0 0 .45rem !important;
  font-size: .875rem;
  line-height: 1.6;
  color: var(--snow);
}

.region-meta-line .key {
  font-family: var(--font-mono);
  font-size: .75rem;
  letter-spacing: .08em;
  color: var(--gold);
}

.region-meta-note {
  margin: .7rem 0 0 !important;
  font-size: .8125rem;
  line-height: 1.75;
  color: var(--steel);
  max-width: 42em;
}

/* ---------- 收束 ---------- */
.about-closing {
  border-top: 1px solid var(--line-dark);
  padding: 2.75rem 0 3.25rem;
  background: var(--ink-night);
}

.about-closing-inner {
  display: grid;
  gap: 1.4rem;
}

.page-about .about-closing-text h2 {
  font-size: clamp(1.25rem, 3vw, 1.625rem);
}

.page-about .about-closing-text p {
  margin-top: .7rem;
  font-size: .9375rem;
  line-height: 1.8;
  color: var(--text-soft);
  max-width: 34em;
}

.about-closing-actions {
  display: flex;
  flex-wrap: wrap;
  gap: .7rem;
}

.about-closing-note {
  font-size: .8125rem;
  line-height: 1.75;
  color: var(--steel);
  margin: 0;
}

.about-closing-note a {
  color: var(--teal);
  text-decoration: none;
  border-bottom: 1px solid rgba(18, 179, 154, .4);
}

.about-closing-note a:hover { border-bottom-color: var(--teal); }

/* ---------- 中等屏幕 ---------- */
@media (min-width: 640px) {
  .about-facts { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .team-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .region-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}

@media (min-width: 760px) {
  .claim-stack { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1.25rem; }

  .milestone {
    grid-template-columns: 118px minmax(0, 1fr);
    gap: 2rem;
    align-items: start;
  }

  @media (hover: hover) {
    .claim-scene {
      max-height: 0;
      opacity: 0;
      overflow: hidden;
      margin-top: 0 !important;
      padding-top: 0;
      padding-bottom: 0;
    }

    .claim-card:hover .claim-scene,
    .claim-card:focus-within .claim-scene {
      max-height: 12rem;
      opacity: 1;
      margin-top: .85rem !important;
      padding-top: .7rem;
      padding-bottom: .7rem;
    }
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .about-hero { padding: 2.5rem 0 4rem; }

  .about-hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: 3.5rem;
    align-items: start;
  }

  .about-hero-side {
    border-top: 0;
    border-left: 1px solid var(--line-dark);
    padding: .25rem 0 .25rem 1.85rem;
    margin-top: .4rem;
  }

  .about-chapter { padding: 3.75rem 0; }

  .about-chapter-grid {
    grid-template-columns: 140px minmax(0, 1fr);
    gap: 3rem;
  }

  .about-chapter-rail {
    flex-direction: column;
    gap: .7rem;
    position: sticky;
    top: 6.5rem;
    align-self: start;
  }

  .about-closing-inner {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 2rem 2.5rem;
  }

  .about-closing-note { grid-column: 1 / -1; }
}

@media (min-width: 1080px) {
  .team-layout {
    grid-template-columns: minmax(0, 1fr) 300px;
    gap: 2rem;
    align-items: start;
  }
}

/* ---------- 窄屏收尾 ---------- */
@media (max-width: 420px) {
  .about-hero::before { left: 10%; right: -30%; }

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

  .milestone-scale a { font-size: .75rem; padding-left: .2rem; }
  .milestone-scale a::before { left: .2rem; }
}