.page-about {
  --page-ab-blue-soft: #EDF4F8;
  --page-ab-soft: #FFF7E8;
  --page-ab-line: rgba(26, 26, 26, 0.14);
  --page-ab-line-light: rgba(255, 255, 255, 0.24);
  background: var(--page-bg);
  color: var(--text-primary);
}

.page-about .page-ab-inner {
  max-width: 1240px;
  margin-inline: auto;
  padding-inline: 20px;
}

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

/* 面包屑 */
.page-about .page-ab-breadcrumb {
  max-width: 1240px;
  margin-inline: auto;
  padding: 18px 20px 10px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 12px;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.5;
}

.page-about .page-ab-breadcrumb a {
  color: var(--text-primary);
  text-decoration: none;
  border-bottom: 1px solid var(--border-rule);
  transition: border-color 120ms ease-out;
}

.page-about .page-ab-breadcrumb a:hover,
.page-about .page-ab-breadcrumb a:focus-visible {
  border-color: var(--accent-orange-red);
}

.page-about .page-ab-breadcrumb-sep {
  color: var(--border-rule);
}

/* Hero 标题带 */
.page-about .page-ab-hero {
  background: var(--deep-purple);
  color: var(--text-inverse);
  padding: 40px 0 48px;
  margin-top: 6px;
  border-bottom: 4px solid var(--accent-green);
}

.page-about .page-ab-hero .page-ab-kicker {
  color: var(--accent-green);
}

.page-about .page-ab-hero h1 {
  margin: 6px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(26px, 5vw, 44px);
  line-height: 1.18;
  letter-spacing: -0.02em;
  color: inherit;
}

.page-about .page-ab-hero-bar {
  display: inline-block;
  margin-inline: 8px;
  color: var(--accent-orange-red);
}

.page-about .page-ab-lead {
  margin: 16px 0 0;
  max-width: 820px;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.85;
  color: rgba(255, 255, 255, 0.84);
}

/* 区块公共 */
.page-about section {
  padding-block: 52px 56px;
}

.page-about .page-ab-section-head {
  margin-bottom: 34px;
}

.page-about .page-ab-section-kicker,
.page-about .page-ab-kicker {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent-orange-red);
  margin-bottom: 10px;
}

.page-about .page-ab-section-head h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(22px, 4vw, 34px);
  letter-spacing: -0.02em;
  line-height: 1.25;
}

.page-about .page-ab-section-lead {
  max-width: 860px;
  margin: 12px 0 0;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.8;
  color: rgba(26, 26, 26, 0.74);
}

/* 收录规模与系列划分 */
.page-about .page-ab-stat-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.page-about .page-ab-stat-card {
  border-radius: var(--radius-card);
  padding: 20px 20px 18px;
  position: relative;
  overflow: hidden;
  transition: transform 150ms ease-out, box-shadow 150ms ease-out;
}

.page-about .page-ab-stat-card--yellow {
  background: var(--card-yellow);
  color: var(--text-primary);
}

.page-about .page-ab-stat-card--orange {
  background: var(--card-orange);
  color: var(--text-inverse);
}

.page-about .page-ab-stat-card--mint {
  background: var(--card-mint);
  color: var(--text-primary);
}

.page-about .page-ab-stat-card--baby-blue {
  background: var(--card-baby-blue);
  color: var(--text-primary);
}

.page-about .page-ab-stat-main {
  display: flex;
  align-items: baseline;
  gap: 8px;
}

.page-about .page-ab-stat-num {
  font-family: var(--font-figure);
  font-weight: 700;
  font-size: 52px;
  line-height: 1;
  letter-spacing: -0.02em;
}

.page-about .page-ab-stat-unit {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
}

.page-about .page-ab-stat-name {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 900;
}

.page-about .page-ab-stat-meta {
  margin: 4px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  opacity: 0.72;
}

.page-about .page-ab-series {
  margin-top: 40px;
  background: #fff;
  border: 1px solid var(--border-rule);
  border-radius: var(--radius-card);
  padding: 20px;
}

.page-about .page-ab-series-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 18px;
}

.page-about .page-ab-series-head h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 900;
}

.page-about .page-ab-series-note {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  color: rgba(26, 26, 26, 0.62);
}

.page-about .page-ab-series-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .page-ab-series-item {
  display: grid;
  grid-template-columns: 44px 1fr 48px;
  align-items: center;
  gap: 10px 12px;
  padding: 12px 0;
  border-bottom: 1px solid var(--border-rule);
}

.page-about .page-ab-series-item:last-child {
  border-bottom: 0;
  padding-bottom: 4px;
}

.page-about .page-ab-series-code {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--accent-orange-red);
}

.page-about .page-ab-series-name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 15px;
}

.page-about .page-ab-series-track {
  grid-column: 1 / -1;
  grid-row: 2;
  height: 14px;
  background: rgba(26, 26, 26, 0.08);
  border-radius: 999px;
  overflow: hidden;
}

.page-about .page-ab-series-fill {
  display: block;
  height: 100%;
  border-radius: 999px;
}

.page-about .page-ab-series-value {
  text-align: right;
  font-family: var(--font-figure);
  font-weight: 700;
  font-size: 18px;
}

.page-about .page-ab-series-value small {
  font-family: var(--font-mono);
  font-size: 12px;
  margin-left: 2px;
}

.page-about .page-ab-series-item:nth-child(1) .page-ab-series-fill {
  width: 14%;
  background: linear-gradient(90deg, var(--card-orange), var(--card-yellow));
}

.page-about .page-ab-series-item:nth-child(2) .page-ab-series-fill {
  width: 15%;
  background: linear-gradient(90deg, var(--card-yellow), var(--card-mint));
}

.page-about .page-ab-series-item:nth-child(3) .page-ab-series-fill {
  width: 17%;
  background: linear-gradient(90deg, var(--card-mint), var(--card-baby-blue));
}

.page-about .page-ab-series-item:nth-child(4) .page-ab-series-fill {
  width: 9%;
  background: linear-gradient(90deg, var(--card-baby-blue), var(--deep-purple));
}

.page-about .page-ab-series-item:nth-child(5) .page-ab-series-fill {
  width: 20%;
  background: linear-gradient(90deg, var(--deep-purple), var(--accent-orange-red));
}

.page-about .page-ab-series-item:nth-child(6) .page-ab-series-fill {
  width: 6%;
  background: linear-gradient(90deg, var(--accent-green), var(--card-mint));
}

.page-about .page-ab-series-item:nth-child(7) .page-ab-series-fill {
  width: 8%;
  background: linear-gradient(90deg, var(--accent-orange-red), var(--card-orange));
}

.page-about .page-ab-series-item:nth-child(8) .page-ab-series-fill {
  width: 12%;
  background: linear-gradient(90deg, var(--dark-cyan), var(--card-baby-blue));
}

/* 分类与标签体系 */
.page-about .page-ab-taxonomy {
  background: var(--page-ab-blue-soft);
}

.page-about .page-ab-taxo-grid {
  display: grid;
  gap: 20px;
}

.page-about .page-ab-tree-card {
  margin: 0;
  background: #fff;
  border: 1px solid var(--border-rule);
  border-radius: var(--radius-card);
  padding: 12px;
}

.page-about .page-ab-tree-img {
  border-radius: calc(var(--radius-card) - 6px);
}

.page-about .page-ab-tree-card figcaption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: rgba(26, 26, 26, 0.66);
}

.page-about .page-ab-tree-levels {
  display: grid;
  gap: 8px;
  margin-top: 14px;
}

.page-about .page-ab-tree-levels p {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 13px;
  display: flex;
  gap: 10px;
  align-items: baseline;
}

.page-about .page-ab-tree-levels span {
  background: var(--deep-purple);
  color: #fff;
  border-radius: 999px;
  padding: 2px 8px;
  font-size: 11px;
  white-space: nowrap;
}

.page-about .page-ab-tag-panel {
  background: #fff;
  border: 1px solid var(--border-rule);
  border-radius: var(--radius-card);
  padding: 22px;
  height: fit-content;
}

.page-about .page-ab-tag-panel-head {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: baseline;
  gap: 8px;
}

.page-about .page-ab-tag-panel-head h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 900;
}

.page-about .page-ab-tag-total {
  font-family: var(--font-mono);
  font-size: 12px;
  background: var(--deep-purple);
  color: #fff;
  padding: 4px 10px;
  border-radius: 999px;
}

.page-about .page-ab-tag-desc {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.7;
  color: rgba(26, 26, 26, 0.72);
}

.page-about .page-ab-tag-wall {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 18px;
}

.page-about .page-ab-tag-wall .tag-chip {
  font-family: var(--font-mono);
  font-size: 13px;
  padding: 8px 14px;
  border-radius: var(--radius-pill);
  text-decoration: none;
  transition: transform 120ms ease-out, box-shadow 120ms ease-out;
  border: 1px solid transparent;
}

.page-about .page-ab-tag-wall .tag-chip:hover,
.page-about .page-ab-tag-wall .tag-chip:focus-visible {
  transform: translateY(-2px);
  box-shadow: var(--shadow-float);
}

.page-about .page-ab-tag-wall .tag-chip--hot {
  background: var(--card-orange);
  color: var(--text-inverse);
}

.page-about .page-ab-tag-wall .tag-chip--cool {
  background: var(--card-baby-blue);
  color: var(--text-primary);
}

.page-about .page-ab-tag-wall .tag-chip--calm {
  background: var(--card-yellow);
  color: var(--text-primary);
}

.page-about .page-ab-tag-tip {
  margin: 18px 0 0;
  font-size: 14px;
  line-height: 1.7;
  background: var(--page-ab-soft);
  border-radius: 12px;
  padding: 10px 14px;
}

.page-about .btn--purple {
  margin-top: 18px;
}

/* 更新机制与批次规则 */
.page-about .page-ab-updates {
  background: var(--dark-cyan);
  color: var(--text-inverse);
}

.page-about .page-ab-updates .page-ab-section-head h2,
.page-about .page-ab-updates .page-ab-section-lead {
  color: var(--text-inverse);
}

.page-about .page-ab-updates .page-ab-section-lead {
  color: rgba(255, 255, 255, 0.82);
}

.page-about .page-ab-updates .page-ab-section-kicker {
  color: var(--accent-green);
}

.page-about .page-ab-rule-chips {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  margin: 0 0 32px;
  padding: 0;
}

.page-about .page-ab-rule-chips li {
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid var(--page-ab-line-light);
  border-radius: var(--radius-card);
  padding: 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .page-ab-rule-chips span {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--accent-green);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.page-about .page-ab-rule-chips strong {
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 700;
}

.page-about .page-ab-timeline {
  list-style: none;
  margin: 0 0 20px;
  padding: 0;
  position: relative;
}

.page-about .page-ab-timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 6px;
  bottom: 6px;
  width: 3px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.28);
}

.page-about .page-ab-timeline-item {
  position: relative;
  padding: 0 0 14px 26px;
}

.page-about .page-ab-timeline-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 18px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--card-mint);
  border: 3px solid var(--dark-cyan);
  box-shadow: 0 0 0 2px rgba(255, 255, 255, 0.35);
}

.page-about .page-ab-timeline-item:nth-child(2)::before {
  background: var(--card-baby-blue);
}

.page-about .page-ab-timeline-item:nth-child(3)::before {
  background: var(--card-yellow);
}

.page-about .page-ab-timeline-item:nth-child(4)::before {
  background: var(--card-orange);
}

.page-about .page-ab-timeline-item:nth-child(5)::before {
  background: var(--status-pending);
}

.page-about .page-ab-version-card {
  background: #fff;
  color: var(--text-primary);
  border-radius: var(--radius-card);
  padding: 14px 16px;
  box-shadow: var(--shadow-float);
  border: 1px solid transparent;
}

.page-about .page-ab-version-card summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
}

.page-about .page-ab-version-card summary::-webkit-details-marker {
  display: none;
}

.page-about .page-ab-version-card[open] summary .page-ab-version-more {
  transform: rotate(180deg);
}

.page-about .page-ab-version-code {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: 999px;
  background: var(--deep-purple);
  color: #fff;
}

.page-about .page-ab-version-card--v32 .page-ab-version-code {
  background: var(--card-mint);
  color: var(--text-primary);
}

.page-about .page-ab-version-card--v31 .page-ab-version-code {
  background: var(--card-baby-blue);
  color: var(--text-primary);
}

.page-about .page-ab-version-card--v30 .page-ab-version-code {
  background: var(--card-yellow);
  color: var(--text-primary);
}

.page-about .page-ab-version-card--v20 .page-ab-version-code {
  background: var(--card-orange);
  color: var(--text-inverse);
}

.page-about .page-ab-version-card--v10 .page-ab-version-code {
  background: var(--status-pending);
  color: var(--text-primary);
}

.page-about .page-ab-version-name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 16px;
}

.page-about .page-ab-version-more {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--accent-orange-red);
  transition: transform 120ms ease-out;
}

.page-about .page-ab-version-desc {
  margin: 12px 0 0;
  font-size: 14px;
  line-height: 1.7;
  border-top: 1px dashed var(--border-rule);
  padding-top: 10px;
}

.page-about .page-ab-update-figure {
  margin: 20px 0 0;
  border-radius: var(--radius-card);
  overflow: hidden;
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid var(--page-ab-line-light);
  padding: 10px;
}

.page-about .page-ab-update-img {
  border-radius: calc(var(--radius-card) - 8px);
}

.page-about .page-ab-update-figure figcaption {
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: rgba(255, 255, 255, 0.72);
}

/* 检索路径与终端支持 */
.page-about .page-ab-access {
  background: var(--page-ab-soft);
}

.page-about .page-ab-access-grid {
  display: grid;
  gap: 16px;
}

.page-about .page-ab-access-card {
  border-radius: var(--radius-card);
  padding: 22px;
  box-shadow: var(--shadow-float);
}

.page-about .page-ab-access-card--route {
  background: var(--deep-purple);
  color: var(--text-inverse);
}

.page-about .page-ab-access-card--device {
  background: var(--card-mint);
  color: var(--text-primary);
}

.page-about .page-ab-access-card h3 {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 900;
  display: inline-block;
  border-radius: 999px;
  padding: 4px 12px;
  font-size: 16px;
}

.page-about .page-ab-access-card--route h3 {
  background: rgba(255, 255, 255, 0.14);
  color: #fff;
}

.page-about .page-ab-access-card--device h3 {
  background: var(--card-yellow);
}

.page-about .page-ab-access-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .page-ab-access-list li {
  font-size: 14px;
  line-height: 1.65;
  padding-left: 24px;
  position: relative;
}

.page-about .page-ab-access-list li::before {
  content: "→";
  position: absolute;
  left: 0;
  top: 0;
  font-family: var(--font-mono);
  font-weight: 700;
}

.page-about .page-ab-access-card--route .page-ab-access-list li::before {
  color: var(--accent-green);
}

.page-about .page-ab-access-card--device .page-ab-access-list li::before {
  color: var(--deep-purple);
}

.page-about .page-ab-access-card a {
  color: inherit;
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-color: currentColor;
  text-decoration-thickness: 1px;
}

.page-about .page-ab-access-card a:hover {
  text-decoration-color: var(--accent-orange-red);
}

.page-about .page-ab-access-figure {
  margin: 16px 0 0;
  background: #fff;
  border: 1px solid var(--border-rule);
  border-radius: var(--radius-card);
  padding: 12px;
  display: flex;
  justify-content: center;
}

.page-about .page-ab-access-img {
  border-radius: calc(var(--radius-card) - 6px);
  max-width: 420px;
  width: 100%;
}

/* 响应式增强 */
@media (hover: hover) {
  .page-about .page-ab-stat-card:hover {
    transform: translateY(-4px) rotate(-0.5deg);
    box-shadow: var(--shadow-float);
  }

  .page-about .page-ab-version-card:hover {
    transform: translateY(-2px);
  }
}

@media (min-width: 720px) {
  .page-about .page-ab-stat-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .page-about .page-ab-rule-chips {
    grid-template-columns: repeat(4, 1fr);
  }

  .page-about .page-ab-access-grid {
    grid-template-columns: 1fr 1fr;
  }

  .page-about .page-ab-access-list li {
    font-size: 15px;
  }

  .page-about .page-ab-tag-wall {
    gap: 12px;
  }
}

@media (min-width: 1040px) {
  .page-about .page-ab-hero {
    padding-block: 56px 64px;
  }

  .page-about section {
    padding-block: 60px 72px;
  }

  .page-about .page-ab-stat-grid {
    grid-template-columns: repeat(4, 1fr);
  }

  .page-about .page-ab-taxo-grid {
    grid-template-columns: 1.05fr 0.95fr;
    align-items: start;
  }

  .page-about .page-ab-series-item {
    grid-template-columns: 48px 180px 1fr 64px;
  }

  .page-about .page-ab-series-code {
    grid-column: 1;
    grid-row: 1;
  }

  .page-about .page-ab-series-name {
    grid-column: 2;
    grid-row: 1;
  }

  .page-about .page-ab-series-track {
    grid-column: 3;
    grid-row: 1;
  }

  .page-about .page-ab-series-value {
    grid-column: 4;
    grid-row: 1;
    text-align: right;
  }

  .page-about .page-ab-rule-chips {
    margin-bottom: 40px;
  }

  .page-about .page-ab-version-card {
    padding: 16px 20px;
  }

  .page-about .page-ab-access-figure {
    padding: 16px;
  }

  .page-about .page-ab-access-img {
    max-width: 460px;
  }
}