.page-about {
  --about-purple: #8E44AD;
  --about-red: #E74C3C;
  --about-green: #2ECC71;
  --about-orange: #E67E22;
  --about-yellow: #F1C40F;
  --about-blue: #3498DB;
  --about-ink-border: 3px solid #1A1A1A;
}

/* ===== 面包屑 ===== */
.page-about .about-breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--ink-soft);
}
.page-about .about-breadcrumb a {
  color: var(--ink-soft);
  text-decoration: none;
  border-bottom: 2px solid var(--orange);
  padding-bottom: 1px;
}
.page-about .about-breadcrumb-sep {
  color: var(--orange);
}

/* ===== Hero ===== */
.page-about .about-hero {
  padding: 24px 0 0;
}
.page-about .about-hero-grid {
  display: grid;
  gap: 32px;
  padding: 24px 0 48px;
}
.page-about .about-hero-copy {
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.page-about .about-hero-kicker {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  color: var(--orange);
  font-weight: 700;
  text-transform: uppercase;
}
.page-about .about-hero h1 {
  font-family: var(--font-heading);
  font-size: clamp(1.75rem, 5vw, 3.4rem);
  font-weight: 900;
  line-height: 1.15;
  color: var(--ink);
  margin: 0;
  max-width: 14em;
}
.page-about .about-hero-desc {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.75;
  color: var(--ink-soft);
  max-width: 42em;
  margin: 0;
}
.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
}
.page-about .about-inline-link {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--ink);
  border-bottom: 2px solid var(--ink);
  text-decoration: none;
  padding-bottom: 2px;
}
.page-about .about-hero-visual {
  position: relative;
  max-width: 640px;
}
.page-about .about-hero-visual-frame {
  background: var(--white);
  border: var(--about-ink-border);
  box-shadow: var(--shadow-hard);
  padding: 8px;
  transform: rotate(1deg);
}
.page-about .about-hero-visual-frame img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  filter: saturate(1.1) contrast(1.05);
}
.page-about .about-hero-visual-tag {
  display: inline-block;
  background: var(--orange);
  color: var(--white);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  padding: 4px 12px;
  position: absolute;
  right: -8px;
  bottom: 24px;
  transform: rotate(-2deg);
  border: 2px solid var(--ink);
  box-shadow: 3px 3px 0 var(--ink);
}

/* ===== 章节头 ===== */
.page-about .section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 16px;
  margin-bottom: 32px;
}
.page-about .section-head .section-index {
  font-family: var(--font-mono);
  font-size: clamp(2.75rem, 7vw, 5rem);
  font-weight: 900;
  line-height: 0.8;
  color: var(--orange);
  letter-spacing: -0.04em;
}
.page-about .section-head .section-title {
  font-family: var(--font-heading);
  font-size: clamp(1.4rem, 3.5vw, 2.2rem);
  font-weight: 900;
  color: var(--ink);
  margin: 0;
}
.page-about .section-head .section-sub {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: var(--ink-soft);
  margin: 0;
  text-transform: uppercase;
}
.page-about .band-dark .section-title,
.page-about .band-green .section-title {
  color: var(--white);
}
.page-about .band-dark .section-sub,
.page-about .band-green .section-sub {
  color: rgba(245, 241, 230, 0.72);
}
.page-about .band-dark .section-index,
.page-about .band-green .section-index {
  color: var(--yellow);
}

/* ===== 01 收录范围 ===== */
.page-about .about-scope {
  padding: 48px 16px;
}
.page-about .about-scope-layout {
  display: grid;
  gap: 32px;
}
.page-about .about-scope-copy {
  display: flex;
  flex-direction: column;
  gap: 20px;
}
.page-about .about-scope-copy p {
  font-family: var(--font-body);
  font-size: 0.95rem;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.92);
  margin: 0;
}
.page-about .about-scope-metrics {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
}
.page-about .about-metric-chip {
  background: rgba(255, 255, 255, 0.08);
  border: 2px solid rgba(255, 255, 255, 0.35);
  padding: 12px;
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.page-about .about-metric-chip-num {
  font-family: var(--font-mono);
  font-size: 1.6rem;
  font-weight: 900;
  color: var(--yellow);
  line-height: 1;
}
.page-about .about-metric-chip-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: rgba(255, 255, 255, 0.72);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}
.page-about .about-scope-tiles {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
}
.page-about .about-scope-tiles .tile-item {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
  min-height: 78px;
  padding: 14px;
  border: var(--about-ink-border);
  border-radius: 0;
  box-shadow: 5px 5px 0 rgba(0, 0, 0, 0.35);
  text-decoration: none;
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}
.page-about .about-scope-tiles .tile-item:hover {
  transform: translate(-2px, -2px);
  box-shadow: 7px 7px 0 rgba(0, 0, 0, 0.5);
}
.page-about .about-scope-tiles .tile-label {
  font-family: var(--font-heading);
  font-size: 1.05rem;
  font-weight: 900;
  color: var(--ink);
  line-height: 1.2;
}
.page-about .about-scope-tiles .tile-count {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--ink-soft);
}

/* ===== 02 分类与索引体系 ===== */
.page-about .about-catalog {
  padding: 48px 16px;
}
.page-about .about-catalog-layout {
  display: grid;
  gap: 28px;
}
.page-about .about-catalog-table-wrap {
  overflow-x: auto;
  border: var(--about-ink-border);
  background: var(--white);
  box-shadow: var(--shadow-hard);
}
.page-about .about-cat-table {
  width: 100%;
  min-width: 420px;
  border-collapse: collapse;
  font-family: var(--font-body);
}
.page-about .about-cat-table th {
  background: var(--ink);
  color: var(--white);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  text-align: left;
  padding: 12px 16px;
  border-bottom: 3px solid var(--ink);
}
.page-about .about-cat-table td {
  padding: 10px 16px;
  font-size: 0.9rem;
  font-weight: 500;
  border-bottom: 1px solid rgba(26, 26, 26, 0.12);
  text-align: right;
}
.page-about .about-cat-table td:first-child {
  text-align: left;
  font-weight: 700;
}
.page-about .about-cat-table tbody tr:nth-child(even) {
  background: rgba(245, 241, 230, 0.55);
}
.page-about .about-cat-table tbody tr:hover {
  background: var(--yellow);
}
.page-about .about-cat-table tbody tr td {
  text-align: right;
}
.page-about .about-cat-table tbody tr td:first-child {
  text-align: left;
}
.page-about .about-cat-table tfoot td {
  background: var(--orange);
  color: var(--white);
  font-family: var(--font-mono);
  font-size: 0.9rem;
  font-weight: 900;
  text-align: right;
  padding: 12px 16px;
  border-top: 2px solid var(--ink);
}
.page-about .about-cat-table tfoot td:first-child {
  text-align: left;
}
.page-about .about-catalog-side {
  display: flex;
  flex-direction: column;
  gap: 20px;
}
.page-about .about-index-card {
  border: var(--about-ink-border);
  background: var(--white);
  padding: 16px;
  box-shadow: 5px 5px 0 rgba(26, 26, 26, 0.16);
}
.page-about .about-index-card h3 {
  font-family: var(--font-heading);
  font-size: 0.95rem;
  font-weight: 900;
  margin: 0 0 12px;
  color: var(--ink);
  border-bottom: 2px solid var(--ink);
  padding-bottom: 6px;
}
.page-about .about-index-card .tag-block {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.page-about .about-index-card .tag-item {
  display: inline-block;
  padding: 5px 12px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  border: 2px solid var(--ink);
  color: var(--ink);
  text-decoration: none;
  transition: background 0.15s ease, color 0.15s ease;
}
.page-about .about-index-card .tag-item:hover {
  background: var(--ink);
  color: var(--white);
}
.page-about .about-index-card .tag-green {
  background: var(--green);
}
.page-about .about-index-card .tag-orange {
  background: var(--orange);
  color: var(--white);
}
.page-about .about-alpha-list {
  list-style: none;
  margin: 0 0 10px;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(28px, 1fr));
  gap: 5px;
}
.page-about .about-alpha-list li {
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  border: 1.5px solid var(--ink);
  background: var(--paper);
  color: var(--ink);
  height: 30px;
}
.page-about .about-index-hint {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--ink-soft);
  margin: 8px 0 0;
  line-height: 1.5;
}
.page-about .about-year-group {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.page-about .about-year-chip {
  background: var(--yellow);
  border: 2px solid var(--ink);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  padding: 5px 10px;
}

/* ===== 03 更新与批次 ===== */
.page-about .about-updates {
  padding: 48px 16px;
}
.page-about .about-update-grid {
  display: grid;
  gap: 22px;
}
.page-about .about-update-card {
  background: rgba(255, 255, 255, 0.07);
  border: 3px solid rgba(255, 255, 255, 0.75);
  padding: 24px 20px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  box-shadow: 7px 7px 0 rgba(0, 0, 0, 0.35);
}
.page-about .about-update-card:hover {
  transform: translateY(-2px);
  box-shadow: 9px 9px 0 rgba(0, 0, 0, 0.45);
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}
.page-about .about-update-badge {
  display: inline-block;
  align-self: flex-start;
  background: var(--purple);
  color: var(--white);
  border: 2px solid var(--ink);
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 3px 10px;
}
.page-about .about-update-card:nth-child(2) .about-update-badge {
  background: var(--orange);
}
.page-about .about-update-card:nth-child(3) .about-update-badge {
  background: var(--red);
}
.page-about .about-update-card h3 {
  font-family: var(--font-heading);
  font-size: 1.2rem;
  font-weight: 900;
  color: var(--white);
  margin: 0;
  line-height: 1.3;
}
.page-about .about-update-card p {
  font-family: var(--font-body);
  font-size: 0.88rem;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.88);
  margin: 0;
}
.page-about .about-update-card .btn {
  align-self: flex-start;
  margin-top: auto;
}

/* ===== 04 终端与版本 ===== */
.page-about .about-devices {
  padding: 48px 16px;
}
.page-about .about-device-layout {
  display: grid;
  gap: 28px;
}
.page-about .about-device-art {
  border: var(--about-ink-border);
  background: var(--white);
  box-shadow: var(--shadow-hard);
  padding: 10px;
}
.page-about .about-device-art img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 8 / 5;
  object-fit: cover;
  border: 1px solid rgba(26, 26, 26, 0.2);
}
.page-about .about-device-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.page-about .about-device-item {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  border: var(--about-ink-border);
  background: var(--white);
  padding: 16px;
  box-shadow: 6px 6px 0 rgba(26, 26, 26, 0.18);
}
.page-about .about-device-icon {
  background: var(--ink);
  color: var(--white);
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 900;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  min-width: 44px;
  border: 2px solid var(--ink);
}
.page-about .about-device-mobile .about-device-icon {
  background: var(--orange);
}
.page-about .about-device-desktop .about-device-icon {
  background: var(--blue);
  color: var(--ink);
}
.page-about .about-device-item h3 {
  font-family: var(--font-heading);
  font-size: 0.98rem;
  font-weight: 900;
  margin: 0 0 6px;
  color: var(--ink);
}
.page-about .about-device-item p {
  font-family: var(--font-body);
  font-size: 0.85rem;
  line-height: 1.65;
  color: var(--ink-soft);
  margin: 0;
}
.page-about .about-version-row {
  display: flex;
  align-items: center;
  gap: 12px;
  border: 2px solid var(--ink);
  background: var(--paper);
  padding: 12px 16px;
}
.page-about .about-version-badge {
  background: var(--green);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 900;
  border: 2px solid var(--ink);
  padding: 4px 12px;
}
.page-about .about-version-text {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--ink-soft);
}

/* ===== 05 使用路径示例 ===== */
.page-about .about-path {
  padding: 48px 16px;
}
.page-about .about-path-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 18px;
}
.page-about .about-path-details {
  border: var(--about-ink-border);
  background: rgba(255, 255, 255, 0.95);
  box-shadow: 7px 7px 0 rgba(0, 0, 0, 0.32);
}
.page-about .about-path-details summary {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 16px;
  cursor: pointer;
  list-style: none;
}
.page-about .about-path-details summary::-webkit-details-marker {
  display: none;
}
.page-about .about-path-details summary img {
  width: 44px;
  height: 44px;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  border: 2px solid var(--ink);
  box-shadow: 2px 2px 0 var(--ink);
  background: var(--paper);
}
.page-about .about-path-title {
  font-family: var(--font-heading);
  font-size: 1.12rem;
  font-weight: 900;
  color: var(--ink);
  line-height: 1.2;
}
.page-about .about-path-item:nth-child(2) .about-path-title {
  color: var(--orange);
}
.page-about .about-path-item:nth-child(3) .about-path-title {
  color: var(--purple);
}
.page-about .about-path-item:nth-child(4) .about-path-title {
  color: var(--red);
}
.page-about .about-path-details p {
  font-family: var(--font-body);
  font-size: 0.88rem;
  line-height: 1.75;
  color: var(--ink-soft);
  margin: 0;
  padding: 0 16px 16px 74px;
}

/* ===== 深色带文字补充 ===== */
.page-about .band-dark p,
.page-about .band-green p {
  color: rgba(255, 255, 255, 0.9);
}

/* ===== 桌面布局 ===== */
@media (min-width: 760px) {
  .page-about .about-hero {
    padding-top: 32px;
  }
  .page-about .about-hero-grid {
    grid-template-columns: 7fr 5fr;
    gap: 48px;
    align-items: center;
  }
  .page-about .about-scope-layout {
    grid-template-columns: 5fr 7fr;
    gap: 48px;
  }
  .page-about .about-catalog-layout {
    grid-template-columns: 7fr 5fr;
    gap: 40px;
  }
  .page-about .about-update-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
  }
  .page-about .about-device-layout {
    grid-template-columns: 8fr 7fr;
    gap: 44px;
    align-items: center;
  }
  .page-about .about-path-list {
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
  }
  .page-about .about-scope-tiles {
    grid-template-columns: repeat(3, 1fr);
  }
  .page-about .about-scope-tiles .tile-item:nth-child(4n) {
    transform: translateY(6px);
  }
  .page-about .about-scope-tiles .tile-item:nth-child(4n+1) {
    transform: translateY(-4px);
  }
}

@media (min-width: 1100px) {
  .page-about .about-hero-grid {
    grid-template-columns: 3fr 2fr;
  }
  .page-about .about-scope-layout {
    grid-template-columns: 4fr 8fr;
  }
  .page-about .about-scope-tiles {
    grid-template-columns: repeat(4, 1fr);
  }
}