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

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

.page-about .mono {
  font-variant-numeric: tabular-nums;
}

/* ============ 面包屑 ============ */
.page-about .about-crumbs {
  padding-top: clamp(16px, 3vw, 28px);
}

/* ============ 首屏档案封面 ============ */
.page-about .about-hero {
  position: relative;
  border-bottom: 1px solid var(--line);
  padding: clamp(26px, 5vw, 52px) 0 clamp(34px, 6vw, 72px);
  background:
    radial-gradient(120% 90% at 86% -20%, rgba(30, 127, 194, 0.38), transparent 62%),
    linear-gradient(180deg, var(--ink-3) 0%, var(--ink) 100%);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(to right, rgba(42, 50, 58, 0.55) 0 1px, transparent 1px 64px),
    repeating-linear-gradient(to bottom, rgba(42, 50, 58, 0.4) 0 1px, transparent 1px 64px);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.85), transparent 90%);
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.85), transparent 90%);
}

.page-about .hero-grid {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 48px);
  align-items: start;
}

.page-about .hero-main {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.page-about .hero-kicker {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--lake-soft);
}

.page-about h1 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(30px, 7.4vw, 62px);
  line-height: 1.1;
  letter-spacing: -0.015em;
  color: var(--paper);
  max-width: 20ch;
}

.page-about .hero-lede {
  margin: 0;
  max-width: 42ch;
  font-size: 16px;
  line-height: 1.75;
  color: #C6CDD4;
}

.page-about .hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 6px;
}

.page-about .hero-actions .btn {
  min-height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

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

.page-about .fact {
  background: var(--ink-2);
  padding: 16px 18px;
  display: grid;
  gap: 4px;
}

.page-about .fact dt {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--mist);
}

.page-about .fact dd {
  margin: 0;
  font-size: 15px;
  line-height: 1.6;
  color: var(--text);
}

.page-about .fact dd .mono {
  color: var(--v-yellow);
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}

/* ============ 章节索引条 ============ */
.page-about .about-index {
  border-bottom: 1px solid var(--line);
  background: rgba(16, 23, 32, 0.92);
  padding: 12px 0;
}

.page-about .about-index .index-strip {
  display: flex;
  gap: 10px;
  overflow-x: auto;
  scroll-snap-type: x proximity;
  padding-bottom: 4px;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-index .index-link {
  flex: 0 0 auto;
  scroll-snap-align: start;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 16px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--text);
  font-size: 14px;
  text-decoration: none;
  white-space: nowrap;
  transition: transform 160ms var(--ease), border-color 160ms var(--ease), color 160ms var(--ease);
}

.page-about .about-index .index-link:hover,
.page-about .about-index .index-link[data-active] {
  transform: translateY(-2px);
  border-color: var(--lake);
  color: var(--lake-soft);
}

/* ============ 章节骨架 ============ */
.page-about .about-chapter {
  padding: clamp(38px, 7vw, 92px) 0;
  border-bottom: 1px solid var(--line);
}

.page-about .chapter-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
}

.page-about .chapter-num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.2em;
  color: var(--sunset);
}

.page-about .chapter-body {
  display: flex;
  flex-direction: column;
  gap: clamp(20px, 3vw, 32px);
}

.page-about .chapter-body h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(24px, 5vw, 40px);
  line-height: 1.2;
  color: var(--paper);
  max-width: 22ch;
}

.page-about .chapter-lede {
  margin: 0;
  max-width: 40ch;
  font-size: 16px;
  line-height: 1.8;
  color: #BEC6CE;
}

/* ============ 时间轴 ============ */
.page-about .timeline-track {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: 82%;
  gap: 16px;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  padding: 4px 0 16px;
  -webkit-overflow-scrolling: touch;
}

.page-about .timeline-step {
  scroll-snap-align: start;
  position: relative;
  background: var(--ink-2);
  border: 1px solid var(--line);
  border-radius: var(--radius-card);
  padding: 22px 20px 20px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  transition: transform 180ms var(--ease), border-color 180ms var(--ease);
}

.page-about .timeline-step::after {
  content: "";
  position: absolute;
  left: 20px;
  right: 20px;
  top: 0;
  height: 3px;
  border-radius: 0 0 3px 3px;
}

.page-about .timeline-step--one::after { background: var(--lake); }
.page-about .timeline-step--two::after { background: var(--v-yellow); }
.page-about .timeline-step--three::after { background: var(--sunset); }

.page-about .timeline-step:hover {
  transform: translateY(-2px);
  border-color: var(--lake);
}

.page-about .step-tag {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--lake-soft);
}

.page-about .timeline-step h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 800;
  color: var(--paper);
}

.page-about .timeline-step p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: #C0C8D0;
}

.page-about .fold {
  border-top: 1px dashed var(--line);
  padding-top: 10px;
}

.page-about .fold summary {
  cursor: pointer;
  list-style: none;
  min-height: 44px;
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--lake-soft);
}

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

.page-about .fold summary::before {
  content: "＋";
  font-family: var(--font-mono);
  color: var(--sunset);
}

.page-about .fold[open] summary::before { content: "－"; }

.page-about .fold-body p {
  margin: 4px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--mist);
}

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

.page-about .about-figure img {
  width: 100%;
  border-radius: var(--radius-card);
  border: 1px solid var(--line);
  object-fit: cover;
}

.page-about .figure-caption {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--mist);
}

/* ============ 团队 ============ */
.page-about .team-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 30px);
}

.page-about .team-blocks {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .team-block {
  border: 1px solid var(--line);
  border-left-width: 4px;
  border-radius: 18px 18px 18px 6px;
  background: var(--ink-2);
  padding: 20px 20px 18px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: transform 180ms var(--ease);
}

.page-about .team-block:hover { transform: translateY(-2px); }

.page-about .team-block--index { border-left-color: var(--lake); }
.page-about .team-block--check { border-left-color: var(--v-green); }
.page-about .team-block--care { border-left-color: var(--sunset); }

.page-about .team-block h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 800;
  color: var(--paper);
}

.page-about .team-block p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: #BFC7CF;
}

.page-about .team-meta {
  margin-top: auto;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--mist);
}

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

.page-about .team-figure img {
  width: 100%;
  border-radius: var(--radius-card);
  border: 1px solid var(--line);
  object-fit: cover;
}

/* ============ 服务区域 ============ */
.page-about .region-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 32px);
}

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

.page-about .region-figure img {
  width: 100%;
  border-radius: var(--radius-card);
  border: 1px solid var(--line);
  object-fit: cover;
}

.page-about .region-copy {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.page-about .region-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
}

.page-about .region-list li {
  display: flex;
  align-items: center;
  gap: 8px;
  min-height: 44px;
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--ink-2);
  font-size: 15px;
  color: var(--text);
}

.page-about .region-list .mono {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--v-yellow);
}

.page-about .region-copy p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: #BFC7CF;
}

/* ============ 收录标准 ============ */
.page-about .rule-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius-card);
  overflow: hidden;
}

.page-about .rule-item {
  background: var(--ink-2);
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  gap: 14px;
  padding: 20px 18px;
}

.page-about .rule-num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 22px;
  color: var(--sunset);
  line-height: 1.2;
}

.page-about .rule-item h3 {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 800;
  color: var(--paper);
}

.page-about .rule-item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: #BFC7CF;
}

.page-about .standard-note {
  display: flex;
  flex-direction: column;
  gap: 14px;
  align-items: flex-start;
  border-left: 3px solid var(--lake);
  padding: 6px 0 6px 18px;
}

.page-about .standard-note p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: #BFC7CF;
  max-width: 46ch;
}

.page-about .standard-note .btn {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
}

/* ============ 数据一览 ============ */
.page-about .about-numbers-table {
  width: 100%;
  border-collapse: collapse;
  min-width: 560px;
  font-size: 15px;
}

.page-about .about-numbers-table caption {
  caption-side: top;
  text-align: left;
  padding: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--mist);
}

.page-about .about-numbers-table th,
.page-about .about-numbers-table td {
  border-bottom: 1px solid var(--line);
  padding: 14px 14px;
  text-align: left;
  vertical-align: top;
}

.page-about .about-numbers-table thead th {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--mist);
  font-weight: 500;
  background: var(--ink-2);
}

.page-about .about-numbers-table tbody th {
  font-weight: 500;
  color: var(--paper);
  background: var(--ink-2);
  position: sticky;
  left: 0;
  min-width: 152px;
}

.page-about .about-numbers-table tbody td {
  color: #BFC7CF;
}

.page-about .about-numbers-table .num-hi {
  font-family: var(--font-mono);
  font-size: 17px;
  color: var(--sunset);
  white-space: nowrap;
}

/* ============ 合作互引 ============ */
.page-about .partner-band {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  background: var(--paper);
  color: var(--ink);
  border-radius: 26px 26px 26px 8px;
  padding: clamp(22px, 4vw, 40px);
}

.page-about .partner-col {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.page-about .partner-col h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 800;
  color: var(--ink);
  padding-bottom: 8px;
  border-bottom: 2px solid var(--lake);
  align-self: flex-start;
}

.page-about .partner-col p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: #2C3339;
}

.page-about .partner-col .btn {
  align-self: flex-start;
  margin-top: 4px;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
}

/* ============ 收尾 ============ */
.page-about .about-cta {
  padding: clamp(38px, 7vw, 84px) 0 clamp(48px, 8vw, 96px);
  background:
    radial-gradient(100% 120% at 10% 0%, rgba(255, 122, 47, 0.16), transparent 58%),
    var(--ink);
}

.page-about .cta-inner {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.page-about .cta-inner h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(23px, 4.6vw, 36px);
  line-height: 1.25;
  color: var(--paper);
  max-width: 24ch;
}

.page-about .cta-inner p {
  margin: 0;
  max-width: 44ch;
  font-size: 16px;
  line-height: 1.8;
  color: #BEC6CE;
}

.page-about .cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 4px;
}

.page-about .cta-actions .btn {
  min-height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

/* ============ 焦点态 ============ */
.page-about a:focus-visible,
.page-about summary:focus-visible {
  outline: 2px solid var(--sunset);
  outline-offset: 3px;
  border-radius: 6px;
}

/* ============ 桌面 ============ */
@media (min-width: 900px) {
  .page-about .hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: clamp(28px, 4vw, 56px);
  }

  .page-about .hero-facts {
    grid-template-columns: minmax(0, 1fr);
    margin-top: 10px;
  }

  .page-about .chapter-grid {
    grid-template-columns: 96px minmax(0, 1fr);
    gap: clamp(24px, 4vw, 56px);
  }

  .page-about .chapter-num {
    position: sticky;
    top: 108px;
    font-size: 14px;
  }

  .page-about .timeline-track {
    grid-auto-flow: row;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    overflow: visible;
    scroll-snap-type: none;
    padding-bottom: 0;
  }

  .page-about .timeline-track .timeline-step:nth-child(2) {
    margin-top: 26px;
  }

  .page-about .timeline-track .timeline-step:nth-child(3) {
    margin-top: 52px;
  }

  .page-about .team-layout {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: start;
  }

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

  .page-about .region-grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
    align-items: start;
  }

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

  .page-about .rule-item {
    grid-template-columns: 72px minmax(0, 1fr);
    padding: 24px 24px;
  }

  .page-about .rule-item:nth-child(even) > div {
    transform: translateX(18px);
  }

  .page-about .partner-band {
    grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
    gap: 48px;
  }

  .page-about .cta-inner {
    max-width: 62ch;
  }
}

@media (min-width: 1200px) {
  .page-about .hero-facts {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .chapter-grid {
    grid-template-columns: 120px minmax(0, 1fr);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .timeline-step,
  .page-about .team-block,
  .page-about .about-index .index-link {
    transition: none;
  }

  .page-about .timeline-step:hover,
  .page-about .team-block:hover,
  .page-about .about-index .index-link:hover,
  .page-about .about-index .index-link[data-active] {
    transform: none;
  }
}