.page-about {
  --about-rule: 3px solid var(--ink);
  --about-rule-light: 2px solid rgba(255, 253, 247, 0.3);
  --about-stat-bg: #f0e6d8;
  font-family: var(--font-body);
  color: var(--ink);
  background: var(--cream);
  min-height: 100vh;
}

.page-about__breadcrumb {
  background: var(--deep-slate);
  padding: 10px 0;
  font-size: 13px;
  color: rgba(255, 253, 247, 0.7);
  border-bottom: 1px solid rgba(255, 253, 247, 0.15);
}
.page-about__breadcrumb a {
  color: var(--amber);
  text-decoration: none;
}
.page-about__breadcrumb a:hover {
  text-decoration: underline;
}
.page-about__crumb-sep {
  margin: 0 8px;
  color: rgba(255, 253, 247, 0.4);
}

/* ===== Hero 数字带 ===== */
.page-about__hero {
  background: var(--deep-slate);
  padding: 48px 0 0;
  border-bottom: 4px solid var(--amber);
}
.page-about__hero-kicker {
  color: var(--amber);
  font-family: var(--font-data);
  font-size: 13px;
  letter-spacing: 0.18em;
  margin: 0 0 12px;
  text-transform: uppercase;
}
.page-about__hero-title {
  color: var(--paper);
  font-family: var(--font-head);
  font-size: 26px;
  font-weight: 900;
  line-height: 1.25;
  margin: 0 0 14px;
  max-width: 680px;
}
.page-about__hero-desc {
  color: rgba(255, 253, 247, 0.78);
  font-size: 15px;
  line-height: 1.65;
  margin: 0 0 28px;
  max-width: 720px;
}
.page-about__stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}
.page-about__stat-card {
  border-radius: 0;
  padding: 18px 16px;
  min-height: 118px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.page-about__stat-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3);
}
.page-about__stat-card--orange {
  background: var(--signal-orange);
  color: var(--ink);
}
.page-about__stat-card--teal {
  background: var(--teal);
  color: var(--paper);
}
.page-about__stat-card--violet {
  background: var(--violet);
  color: var(--paper);
}
.page-about__stat-card--amber {
  background: var(--amber);
  color: var(--ink);
}
.page-about__stat-value {
  font-family: var(--font-data);
  font-size: 34px;
  font-weight: 700;
  line-height: 1;
}
.page-about__stat-label {
  font-family: var(--font-head);
  font-size: 15px;
  font-weight: 700;
  margin-top: 10px;
}
.page-about__stat-note {
  font-size: 12px;
  opacity: 0.75;
  margin-top: 4px;
  font-family: var(--font-data);
}
.page-about__hero-texture {
  display: block;
  width: 100%;
  height: auto;
  margin-top: 40px;
  opacity: 0.8;
}

/* ===== 通用分区 ===== */
.page-about__section {
  padding: 44px 0;
}
.page-about__section--cream {
  background: var(--cream);
}
.page-about__section--gray {
  background: var(--light-gray);
}
.page-about__section--dark {
  background: var(--deep-slate);
  color: var(--cream);
  border-top: 4px solid var(--signal-orange);
  border-bottom: 4px solid var(--signal-orange);
}
.page-about__section-head {
  margin-bottom: 24px;
  border-bottom: var(--about-rule);
  padding-bottom: 14px;
}
.page-about__section-head--dark {
  border-bottom: var(--about-rule-light);
}
.page-about__kicker {
  font-family: var(--font-data);
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  display: block;
  margin-bottom: 8px;
  color: var(--teal);
  font-weight: 600;
}
.page-about__kicker--dark {
  color: var(--amber);
}
.page-about__h2 {
  font-family: var(--font-head);
  font-size: 21px;
  font-weight: 900;
  margin: 0;
  line-height: 1.3;
}
.page-about__h3 {
  font-family: var(--font-head);
  font-size: 16px;
  font-weight: 700;
  margin: 0 0 10px;
}
.page-about__h3--dark {
  color: var(--cream);
}
.page-about__section-lead {
  font-size: 14px;
  line-height: 1.6;
  margin: 0 0 24px;
  max-width: 800px;
  color: rgba(15, 17, 21, 0.78);
}

/* ===== 树状结构：收录范围 ===== */
.page-about__tree {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}
.page-about__tree-group {
  background: var(--paper);
  border-left: 4px solid var(--teal);
  box-shadow: 0 1px 4px rgba(15, 17, 21, 0.08);
}
.page-about__tree-group:has(.page-about__tree-dot--orange) {
  border-left-color: var(--signal-orange);
}
.page-about__tree-group:has(.page-about__tree-dot--teal) {
  border-left-color: var(--teal);
}
.page-about__tree-group:has(.page-about__tree-dot--violet) {
  border-left-color: var(--violet);
}
.page-about__tree-root {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 16px;
  cursor: pointer;
  user-select: none;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 15px;
}
.page-about__tree-dot {
  width: 14px;
  height: 14px;
  flex: 0 0 14px;
  border-radius: 50%;
}
.page-about__tree-dot--orange {
  background: var(--signal-orange);
}
.page-about__tree-dot--teal {
  background: var(--teal);
}
.page-about__tree-dot--violet {
  background: var(--violet);
}
.page-about__tree-name {
  flex: 1;
}
.page-about__tree-count {
  font-family: var(--font-data);
  font-size: 14px;
  color: var(--ink);
  background: var(--cream);
  padding: 2px 8px;
  font-weight: 600;
}
.page-about__tree-versions {
  list-style: none;
  margin: 0;
  padding: 0 16px 14px 40px;
  display: grid;
  gap: 6px;
}
.page-about__tree-versions li {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 13px;
  color: rgba(15, 17, 21, 0.78);
  border-bottom: 1px solid var(--light-gray);
  padding: 4px 0;
}
.page-about__tree-version {
  font-family: var(--font-data);
}

.page-about__archive {
  margin-top: 24px;
  background: var(--deep-slate);
  color: var(--paper);
  padding: 18px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  border-left: 4px solid var(--amber);
}
.page-about__archive-badge {
  background: var(--amber);
  color: var(--ink);
  font-family: var(--font-data);
  font-size: 12px;
  font-weight: 700;
  padding: 4px 10px;
  letter-spacing: 0.1em;
}
.page-about__archive-name {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 15px;
}
.page-about__archive-count {
  font-family: var(--font-data);
  font-size: 20px;
  color: var(--amber);
  font-weight: 700;
}

/* ===== 分类与标签 ===== */
.page-about__taxonomy {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}
.page-about__taxonomy-sidebar {
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.page-about__taxonomy-figure {
  width: 100%;
  height: auto;
  max-width: 400px;
  background: var(--deep-slate);
}
.page-about__taxonomy-levels {
  background: var(--paper);
  padding: 18px;
  border-top: 3px solid var(--ink);
  max-width: 400px;
}
.page-about__level-list {
  margin: 0;
  padding-left: 20px;
  display: grid;
  gap: 10px;
  font-size: 14px;
}
.page-about__level-list li {
  display: grid;
  gap: 2px;
}
.page-about__level-list strong {
  font-family: var(--font-head);
  color: var(--ink);
}
.page-about__level-list span {
  color: var(--deep-slate);
  font-size: 13px;
  opacity: 0.8;
}
.page-about__taxonomy-tags {
  background: var(--paper);
  padding: 20px;
  border-left: 4px solid var(--violet);
}
.page-about__taggroup {
  margin-bottom: 20px;
}
.page-about__taggroup--lg .tag {
  font-size: 15px;
  font-weight: 700;
}
.page-about__taggroup-label {
  display: block;
  font-family: var(--font-data);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: rgba(15, 17, 21, 0.55);
  margin-bottom: 8px;
  font-weight: 600;
}

/* ===== 更新机制 ===== */
.page-about__flow {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
  margin-bottom: 24px;
}
.page-about__flow-steps {
  display: flex;
  flex-direction: column;
  gap: 0;
}
.page-about__flow-step {
  background: rgba(255, 253, 247, 0.06);
  border-left: 3px solid var(--amber);
  padding: 16px;
  min-height: 90px;
}
.page-about__flow-num {
  font-family: var(--font-data);
  font-size: 24px;
  color: var(--amber);
  font-weight: 700;
  display: block;
}
.page-about__flow-title {
  display: block;
  font-family: var(--font-head);
  font-weight: 700;
  color: var(--paper);
  font-size: 15px;
  margin: 6px 0 4px;
}
.page-about__flow-desc {
  display: block;
  font-size: 13px;
  color: rgba(255, 253, 247, 0.6);
}
.page-about__flow-arrow {
  color: var(--signal-orange);
  font-size: 22px;
  text-align: center;
  padding: 2px 0;
  display: block;
  line-height: 1;
}
.page-about__batch-demo {
  background: var(--amber);
  color: var(--ink);
  padding: 18px;
  display: grid;
  gap: 6px;
  justify-items: start;
}
.page-about__batch-label {
  font-family: var(--font-data);
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  opacity: 0.65;
}
.page-about__batch-sample {
  font-family: var(--font-data);
  font-size: 28px;
  font-weight: 700;
  line-height: 1.2;
}
.page-about__batch-note {
  font-size: 13px;
  opacity: 0.8;
}
.page-about__flow-figure {
  width: 100%;
  height: auto;
  max-width: 400px;
  background: rgba(255, 253, 247, 0.08);
}
.page-about__changelog {
  border-top: var(--about-rule-light);
  padding-top: 20px;
}
.page-about__changelog-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 8px;
}
.page-about__changelog-list li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  font-size: 14px;
  color: rgba(255, 253, 247, 0.82);
  padding: 8px 0;
  border-bottom: 1px solid rgba(255, 253, 247, 0.12);
}
.page-about__changelog-batch {
  font-family: var(--font-data);
  background: var(--signal-orange);
  color: var(--ink);
  font-weight: 700;
  font-size: 12px;
  padding: 2px 8px;
}

/* ===== 版本与终端适配 ===== */
.page-about__adapt {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}
.page-about__adapt-card {
  padding: 22px;
  border-top: 4px solid var(--teal);
  background: var(--paper);
}
.page-about__adapt-card--desktop {
  border-top-color: var(--signal-orange);
}
.page-about__adapt-card--mobile {
  border-top-color: var(--violet);
}
.page-about__adapt-icon {
  font-size: 24px;
  display: inline-block;
  margin-bottom: 8px;
  color: var(--deep-slate);
}
.page-about__adapt-list {
  margin: 0;
  padding-left: 18px;
  list-style: square;
  display: grid;
  gap: 6px;
  font-size: 14px;
}
.page-about__adapt-list li {
  padding-left: 4px;
}
.page-about__adapt-list li::marker {
  color: var(--teal);
}
.page-about__adapt-card--desktop .page-about__adapt-list li::marker {
  color: var(--signal-orange);
}
.page-about__adapt-card--mobile .page-about__adapt-list li::marker {
  color: var(--violet);
}

/* ===== 检索与筛选 ===== */
.page-about__filters {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}
.page-about__filter-group {
  background: var(--paper);
  padding: 16px;
  border-bottom: 2px solid var(--ink);
}
.page-about__filter-label {
  display: block;
  font-family: var(--font-data);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  margin-bottom: 10px;
  color: var(--deep-slate);
  opacity: 0.6;
  font-weight: 600;
}
.page-about__search-hint {
  margin-top: 20px;
  background: var(--deep-slate);
  color: var(--paper);
  padding: 18px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
}
.page-about__search-hint-title {
  font-family: var(--font-head);
  font-weight: 700;
  margin-right: auto;
}

/* ===== 评分方法 ===== */
.page-about__scores {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}
.page-about__score-card {
  padding: 16px;
  background: var(--paper);
  border-left: 4px solid var(--teal);
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 8px;
  align-items: center;
}
.page-about__score-card--orange {
  border-left-color: var(--signal-orange);
}
.page-about__score-card--teal {
  border-left-color: var(--teal);
}
.page-about__score-card--violet {
  border-left-color: var(--violet);
}
.page-about__score-card--amber {
  border-left-color: var(--amber);
}
.page-about__score-card--slate {
  border-left-color: var(--deep-slate);
}
.page-about__score-name {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 15px;
}
.page-about__score-points {
  font-family: var(--font-data);
  font-weight: 700;
  font-size: 16px;
  color: var(--deep-slate);
}
.page-about__score-card .metric-bar {
  grid-column: 1 / -1;
  margin-top: 2px;
}
.page-about__score-total {
  margin-top: 20px;
  background: var(--ink);
  color: var(--paper);
  padding: 20px;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 12px;
  border-left: 6px solid var(--amber);
}
.page-about__score-total-label {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 16px;
}
.page-about__score-total-value {
  font-family: var(--font-data);
  font-size: 40px;
  font-weight: 700;
  color: var(--amber);
  line-height: 1;
}
.page-about__score-total-note {
  font-size: 13px;
  color: rgba(255, 253, 247, 0.6);
  margin-left: auto;
}

/* ===== 底部导航带 ===== */
.page-about__navband {
  background: var(--deep-slate);
  color: var(--paper);
  padding: 44px 0;
  border-top: 4px solid var(--signal-orange);
}
.page-about__navband-head {
  margin-bottom: 20px;
}
.page-about__navgrid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}
.page-about__navlink {
  display: block;
  padding: 20px;
  text-decoration: none;
  transition: transform 0.2s ease;
}
.page-about__navlink:hover {
  transform: translateX(6px);
}
.page-about__navlink--orange {
  background: var(--signal-orange);
  color: var(--ink);
}
.page-about__navlink--teal {
  background: var(--teal);
  color: var(--paper);
}
.page-about__navlink--violet {
  background: var(--violet);
  color: var(--paper);
}
.page-about__navlink-title {
  display: block;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 18px;
  margin-bottom: 4px;
}
.page-about__navlink-desc {
  display: block;
  font-size: 13px;
  opacity: 0.85;
}

/* ===== 平板适配 ===== */
@media (min-width: 640px) {
  .page-about__hero-title {
    font-size: 34px;
  }
  .page-about__stats {
    grid-template-columns: repeat(4, 1fr);
    gap: 18px;
  }
  .page-about__stat-card {
    min-height: 140px;
    padding: 22px 18px;
  }
  .page-about__stat-value {
    font-size: 42px;
  }
  .page-about__section {
    padding: 56px 0;
  }
  .page-about__h2 {
    font-size: 26px;
  }
  .page-about__tree {
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
  }
  .page-about__taxonomy {
    grid-template-columns: 380px 1fr;
    gap: 40px;
  }
  .page-about__flow-steps {
    flex-direction: row;
    flex-wrap: wrap;
  }
  .page-about__flow-step {
    flex: 1 1 150px;
  }
  .page-about__flow-arrow {
    padding: 0 4px;
    font-size: 28px;
    align-self: center;
  }
}

/* ===== 桌面适配 ===== */
@media (min-width: 960px) {
  .page-about__hero {
    padding-top: 64px;
  }
  .page-about__hero-kicker {
    font-size: 14px;
  }
  .page-about__hero-title {
    font-size: 40px;
  }
  .page-about__hero-desc {
    font-size: 16px;
  }
  .page-about__stat-card {
    min-height: 150px;
    padding: 26px 22px;
  }
  .page-about__stat-value {
    font-size: 48px;
  }
  .page-about__stat-label {
    font-size: 16px;
  }
  .page-about__section {
    padding: 72px 0;
  }
  .page-about__section-lead {
    font-size: 15px;
  }
  .page-about__taxonomy-tags {
    padding: 28px;
  }
  .page-about__flow {
    grid-template-columns: 1fr 1fr;
    align-items: start;
  }
  .page-about__batch-demo {
    grid-column: 2;
    grid-row: 1;
  }
  .page-about__flow-figure {
    grid-column: 2;
    grid-row: 2;
  }
  .page-about__adapt {
    grid-template-columns: 1fr 1fr;
    gap: 20px;
  }
  .page-about__filters {
    grid-template-columns: 1fr 1fr;
  }
  .page-about__scores {
    grid-template-columns: repeat(5, 1fr);
    gap: 14px;
  }
  .page-about__score-card {
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 12px;
    justify-content: flex-start;
    min-height: 130px;
  }
  .page-about__score-card .metric-bar {
    grid-column: auto;
    margin-top: auto;
  }
  .page-about__navgrid {
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
  }
  .page-about__navlink {
    padding: 28px;
  }
}