.page-about {
  max-width: var(--container);
  margin-inline: auto;
  padding: 20px 20px 72px;
  color: var(--gray);
  overflow-wrap: break-word;
}

/* 面包屑 */
.page-about .breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  margin-bottom: 18px;
}
.page-about .breadcrumbs a {
  color: var(--blue);
  text-decoration: none;
  font-weight: 700;
}
.page-about .breadcrumbs a:hover {
  color: var(--orange);
  text-decoration: underline;
}

/* 首屏 */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  isolation: isolate;
  border: 2px solid var(--ink);
  border-radius: var(--radius-lg);
  background: var(--white);
  box-shadow: var(--shadow-md);
  padding: 36px 24px 32px;
}
.page-about .about-hero::before,
.page-about .about-hero::after {
  content: "";
  position: absolute;
  border-radius: 50%;
  pointer-events: none;
}
.page-about .about-hero::before {
  width: 220px;
  height: 220px;
  background: var(--yellow);
  top: -90px;
  right: -70px;
}
.page-about .about-hero::after {
  width: 92px;
  height: 92px;
  background: var(--teal);
  top: 88px;
  right: 86px;
  border: 3px solid var(--ink);
}
.page-about .about-hero > * {
  position: relative;
  z-index: 1;
}
.page-about .about-hero__eyebrow {
  font-family: var(--font-tag);
  font-size: 13px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--orange);
  margin: 0 0 6px;
}
.page-about .about-hero__title {
  font-family: var(--font-display);
  font-size: clamp(28px, 4.8vw, 50px);
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--ink);
  margin: 0 0 12px;
}
.page-about .about-hero__title span {
  display: block;
  color: var(--blue);
  font-size: 0.72em;
  letter-spacing: 0;
  margin-top: 4px;
}
.page-about .about-hero__lead {
  max-width: 54em;
  font-size: 15px;
  line-height: 1.75;
  color: var(--gray);
  margin: 0 0 22px;
}
.page-about .about-hero__lead strong {
  color: var(--orange);
}
.page-about .about-hero__years {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  max-width: 560px;
}
.page-about .about-hero__year-card {
  display: block;
  text-decoration: none;
  color: var(--ink);
  border: 2px solid var(--ink);
  border-radius: var(--radius-md);
  padding: 14px 8px 12px;
  text-align: center;
  box-shadow: 3px 3px 0 var(--ink);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.page-about .about-hero__year-card:hover {
  transform: translate(2px, 2px);
  box-shadow: 0 0 0 var(--ink);
}
.page-about .about-hero__year-card--2023 {
  background: var(--coral);
}
.page-about .about-hero__year-card--2024 {
  background: var(--teal);
}
.page-about .about-hero__year-card--2025 {
  background: var(--yellow);
}
.page-about .about-hero__year-label {
  display: block;
  font-family: var(--font-display);
  font-size: 15px;
}
.page-about .about-hero__year-num {
  display: block;
  font-family: var(--font-display);
  font-size: clamp(22px, 4vw, 28px);
  line-height: 1.1;
  margin: 2px 0;
}
.page-about .about-hero__year-batch {
  font-family: var(--font-tag);
  font-size: 10px;
  opacity: 0.85;
}

/* 章节面板 */
.page-about .about-panel {
  border: 2px solid var(--ink);
  border-radius: var(--radius-lg);
  padding: 38px 22px;
  margin-top: 30px;
  box-shadow: var(--shadow-md);
}
.page-about .about-panel--scope {
  background: var(--paper-deep);
  color: var(--ink);
}
.page-about .about-panel--tree {
  background: var(--teal);
  color: var(--ink);
}
.page-about .about-panel--flow {
  background: var(--yellow);
  color: var(--ink);
}
.page-about .about-panel--path {
  background: var(--lilac);
  color: var(--white);
}
.page-about .about-panel__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 14px;
  margin-bottom: 22px;
}
.page-about .about-panel__index {
  font-family: var(--font-display);
  font-size: 28px;
  line-height: 1;
  color: var(--orange);
}
.page-about .about-panel--tree .about-panel__index,
.page-about .about-panel--flow .about-panel__index {
  color: var(--ink);
}
.page-about .about-panel--path .about-panel__index {
  color: var(--yellow);
}
.page-about .about-panel__head h2 {
  font-family: var(--font-display);
  font-size: clamp(24px, 3.2vw, 36px);
  line-height: 1.12;
  margin: 0;
}
.page-about .about-panel__lead {
  flex-basis: 100%;
  font-size: 14px;
  line-height: 1.55;
  margin: 2px 0 0;
  opacity: 0.86;
}
.page-about .about-panel--path .about-panel__lead {
  opacity: 0.92;
}

/* 01 收录口径 */
.page-about .about-scope {
  display: grid;
  gap: 16px;
}
.page-about .about-scope-card {
  border: 2px solid var(--ink);
  border-radius: var(--radius-md);
  padding: 22px 18px;
  box-shadow: 3px 3px 0 var(--ink);
}
.page-about .about-scope-card h3 {
  font-family: var(--font-display);
  font-size: 17px;
  margin: 0 0 10px;
}
.page-about .about-scope-card p {
  font-size: 14px;
  line-height: 1.65;
  margin: 0 0 14px;
}
.page-about .about-scope-card--ink {
  background: var(--ink);
  color: var(--white);
}
.page-about .about-scope-card--teal {
  background: var(--teal);
  color: var(--ink);
}
.page-about .about-scope-card--yellow {
  background: var(--yellow);
  color: var(--ink);
}
.page-about .about-scope-card__chip {
  display: inline-block;
  font-family: var(--font-tag);
  font-size: 12px;
  border: 1.5px solid currentColor;
  border-radius: var(--radius-pill);
  padding: 3px 10px;
  margin: 0 6px 6px 0;
}

/* 02 分类体系 */
.page-about .about-tree {
  display: grid;
  gap: 18px;
}
.page-about .about-tree__main {
  display: grid;
  gap: 18px;
}
.page-about .about-tree__side {
  display: grid;
  gap: 18px;
  align-content: start;
}
.page-about .about-tree-card,
.page-about .about-tagcloud-card {
  background: var(--white);
  border: 2px solid var(--ink);
  border-radius: var(--radius-md);
  padding: 22px 18px;
  box-shadow: var(--shadow-card);
  color: var(--gray);
}
.page-about .about-tree-card h3,
.page-about .about-tagcloud-card h3 {
  font-family: var(--font-display);
  font-size: 16px;
  margin: 0 0 10px;
  color: var(--ink);
}
.page-about .about-tagcloud-card p {
  font-size: 13px;
  line-height: 1.6;
  margin: 0 0 14px;
}

/* 扇形图与图例 */
.page-about .about-tree-fan {
  position: relative;
  width: min(210px, 72%);
  aspect-ratio: 1;
  margin: 16px auto 20px;
  border-radius: 50%;
  border: 4px solid var(--white);
  box-shadow: 0 0 0 2px var(--ink);
  background: conic-gradient(
    var(--blue) 0 47.5%,
    var(--teal) 47.5% 79.5%,
    var(--coral) 79.5% 100%
  );
}
.page-about .about-tree-fan::after {
  content: "";
  position: absolute;
  inset: 30%;
  background: var(--white);
  border: 2px solid var(--ink);
  border-radius: 50%;
}
.page-about .about-tree-fan__legend {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px 16px;
  margin: 0;
  padding: 0;
}
.page-about .about-tree-fan__legend li {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--ink);
}
.page-about .about-tree-fan__dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}
.page-about .about-tree-fan__dot--func {
  background: var(--blue);
}
.page-about .about-tree-fan__dot--step {
  background: var(--teal);
}
.page-about .about-tree-fan__dot--fix {
  background: var(--coral);
}

/* 树状层级 */
.page-about .about-tree-hierarchy__root {
  display: inline-block;
  font-family: var(--font-display);
  font-size: 14px;
  background: var(--ink);
  color: var(--white);
  border-radius: var(--radius-sm);
  padding: 9px 14px;
  margin-bottom: 12px;
}
.page-about .about-tree-hierarchy__list {
  list-style: none;
  margin: 0;
  padding: 4px 0 4px 22px;
  border-left: 2px solid var(--ink);
}
.page-about .about-tree-hierarchy__list li {
  position: relative;
  margin: 12px 0;
}
.page-about .about-tree-hierarchy__list li::before {
  content: "";
  position: absolute;
  left: -22px;
  top: 50%;
  width: 15px;
  height: 2px;
  background: var(--ink);
}
.page-about .about-tree-hierarchy__list a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  min-width: 140px;
  padding: 8px 14px;
  background: var(--paper);
  border: 2px solid var(--ink);
  border-radius: var(--radius-pill);
  color: var(--ink);
  font-weight: 700;
  font-size: 14px;
  text-decoration: none;
  transition: background 0.15s ease, transform 0.15s ease, box-shadow 0.15s ease;
}
.page-about .about-tree-hierarchy__list a:hover {
  background: var(--yellow);
  transform: translateX(3px);
  box-shadow: 2px 2px 0 var(--ink);
}
.page-about .about-tree-hierarchy__list b {
  font-family: var(--font-tag);
  font-size: 12px;
  background: var(--ink);
  color: var(--white);
  border-radius: var(--radius-pill);
  padding: 2px 7px;
}

/* 标签云 */
.page-about .about-tagcloud {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.page-about .about-tagcloud a {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  border: 2px solid var(--ink);
  border-radius: var(--radius-pill);
  background: var(--white);
  color: var(--ink);
  font-family: var(--font-tag);
  text-decoration: none;
  padding: 5px 12px;
  line-height: 1.2;
  transition: background 0.15s ease, transform 0.15s ease;
}
.page-about .about-tagcloud a:hover {
  background: var(--yellow);
  transform: translateY(-2px);
}
.page-about .about-tagcloud a span {
  font-size: 10px;
  background: var(--ink);
  color: var(--white);
  border-radius: var(--radius-pill);
  padding: 2px 6px;
}
.page-about .about-tagcloud__item--lg {
  font-size: 17px;
}
.page-about .about-tagcloud__item--md {
  font-size: 14px;
}
.page-about .about-tagcloud__item--sm {
  font-size: 12px;
}
.page-about .about-tagcloud__item--hot::after {
  content: "";
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--red);
  margin-left: 2px;
}

/* 图片图位 */
.page-about .about-tree-figure,
.page-about .about-flow-figure,
.page-about .about-path-figure {
  margin: 0;
  background: var(--white);
  border: 2px solid var(--ink);
  border-radius: var(--radius-md);
  padding: 10px;
  box-shadow: var(--shadow-card);
}
.page-about .about-tree-figure img,
.page-about .about-flow-figure img,
.page-about .about-path-figure img {
  display: block;
  max-width: 100%;
  height: auto;
  object-fit: contain;
  border-radius: 10px;
}

/* 03 更新机制 */
.page-about .about-flow {
  display: grid;
  gap: 22px;
}
.page-about .about-flow-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}
.page-about .about-flow-step {
  position: relative;
  background: var(--white);
  border: 2px solid var(--ink);
  border-radius: var(--radius-md);
  padding: 22px 16px 16px;
  box-shadow: 3px 3px 0 var(--ink);
  color: var(--gray);
}
.page-about .about-flow-step__num {
  position: absolute;
  top: -12px;
  left: 14px;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--orange);
  color: var(--white);
  border: 2px solid var(--ink);
  display: grid;
  place-items: center;
  font-family: var(--font-display);
  font-size: 13px;
}
.page-about .about-flow-step h3 {
  font-family: var(--font-display);
  font-size: 15px;
  margin: 0 0 6px;
  color: var(--ink);
}
.page-about .about-flow-step p {
  font-size: 13px;
  line-height: 1.6;
  margin: 0;
}
.page-about .about-flow-step__link {
  display: inline-block;
  margin-top: 10px;
  font-size: 13px;
  font-weight: 700;
  color: var(--orange);
  text-decoration: underline;
  text-underline-offset: 3px;
}
.page-about .about-flow-step__link:hover {
  color: var(--ink);
}
.page-about .about-flow-side {
  display: grid;
  gap: 18px;
  align-content: start;
}
.page-about .about-flow-card {
  background: var(--white);
  border: 2px solid var(--ink);
  border-radius: var(--radius-md);
  padding: 22px 18px;
  box-shadow: var(--shadow-card);
  color: var(--gray);
}
.page-about .about-flow-card h3 {
  font-family: var(--font-display);
  font-size: 16px;
  margin: 0 0 12px;
  color: var(--ink);
}
.page-about .about-flow-card p {
  font-size: 13px;
  line-height: 1.6;
  margin: 12px 0 0;
}

/* 批次 */
.page-about .about-batch-list {
  display: grid;
  gap: 12px;
}
.page-about .about-batch-line {
  display: grid;
  gap: 7px;
}
.page-about .about-batch-year {
  display: inline-block;
  width: fit-content;
  font-family: var(--font-display);
  font-size: 13px;
  padding: 4px 12px;
  border-radius: var(--radius-pill);
  border: 1.5px solid var(--ink);
}
.page-about .about-batch-year--2023 {
  background: var(--coral);
  color: var(--ink);
}
.page-about .about-batch-year--2024 {
  background: var(--teal);
  color: var(--ink);
}
.page-about .about-batch-year--2025 {
  background: var(--yellow);
  color: var(--ink);
}
.page-about .about-batch-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.page-about .about-batch-chip {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-family: var(--font-tag);
  font-size: 12px;
  background: var(--paper);
  border: 1.5px solid var(--ink);
  border-radius: var(--radius-pill);
  padding: 3px 9px;
}
.page-about .about-batch-chip b {
  background: var(--ink);
  color: var(--white);
  border-radius: var(--radius-pill);
  font-size: 10px;
  padding: 1px 5px;
}
.page-about .about-batch-chip--current {
  background: var(--orange);
  color: var(--white);
  border-color: var(--ink);
}
.page-about .about-batch-chip--current b {
  background: var(--white);
  color: var(--ink);
}

/* 版本沿革 */
.page-about .about-version-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}
.page-about .about-version-list li {
  display: grid;
  grid-template-columns: 52px 1fr;
  gap: 10px;
  align-items: baseline;
  font-size: 14px;
  line-height: 1.55;
}
.page-about .about-version-tag {
  font-family: var(--font-display);
  font-size: 14px;
  color: var(--blue);
  font-weight: 700;
}

/* 04 检索路径 */
.page-about .about-paths {
  display: grid;
  gap: 16px;
}
.page-about .about-path-card {
  display: flex;
  flex-direction: column;
  background: var(--white);
  border: 2px solid var(--ink);
  border-radius: var(--radius-md);
  padding: 24px 20px 20px;
  box-shadow: var(--shadow-card);
  color: var(--gray);
}
.page-about .about-path-card__badge {
  width: 62px;
  height: 62px;
  border-radius: 50%;
  border: 2px solid var(--ink);
  display: grid;
  place-items: center;
  text-align: center;
  font-family: var(--font-display);
  font-size: 13px;
  line-height: 1.15;
  margin-bottom: 14px;
  color: var(--ink);
}
.page-about .about-path-card__badge--year {
  background: var(--yellow);
}
.page-about .about-path-card__badge--tag {
  background: var(--teal);
}
.page-about .about-path-card__badge--search {
  background: var(--coral);
}
.page-about .about-path-card h3 {
  font-family: var(--font-display);
  font-size: 17px;
  color: var(--ink);
  margin: 0 0 8px;
}
.page-about .about-path-card p {
  font-size: 14px;
  line-height: 1.65;
  margin: 0 0 16px;
  flex-grow: 1;
}
.page-about .about-path-card .btn {
  align-self: flex-start;
}
.page-about .about-path-bottom {
  display: grid;
  gap: 18px;
  margin-top: 22px;
}
.page-about .about-retrieval-demo {
  background: var(--white);
  border: 2px solid var(--ink);
  border-radius: var(--radius-md);
  padding: 24px 20px;
  color: var(--gray);
  box-shadow: var(--shadow-card);
}
.page-about .about-retrieval-demo h3 {
  font-family: var(--font-display);
  font-size: 16px;
  color: var(--ink);
  margin: 0 0 12px;
}
.page-about .about-path-search {
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--paper);
  border: 2px solid var(--ink);
  border-radius: var(--radius-pill);
  padding: 11px 18px;
  margin-bottom: 12px;
}
.page-about .about-path-search__icon {
  display: inline-flex;
  color: var(--blue);
}
.page-about .about-path-search__text {
  font-family: var(--font-tag);
  font-size: 14px;
  color: var(--gray);
}
.page-about .about-retrieval-demo p {
  font-size: 13px;
  line-height: 1.6;
  margin: 0;
}
.page-about .about-path-links {
  display: flex;
  flex-wrap: wrap;
  align-content: center;
  gap: 12px;
}
.page-about .about-path-links a {
  display: inline-block;
  padding: 12px 20px;
  background: var(--ink);
  color: var(--white);
  border-radius: var(--radius-pill);
  text-decoration: none;
  font-size: 14px;
  font-weight: 700;
  border: 2px solid var(--ink);
  transition: background 0.15s ease, transform 0.15s ease, box-shadow 0.15s ease;
}
.page-about .about-path-links a:hover {
  background: var(--orange);
  transform: translateY(-2px);
  box-shadow: 0 4px 0 var(--ink);
}

/* 响应式 */
@media (min-width: 700px) {
  .page-about .about-scope {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (min-width: 860px) {
  .page-about .about-tree {
    grid-template-columns: 1.2fr 0.8fr;
  }
  .page-about .about-tree__main {
    grid-template-columns: 1fr 1fr;
  }
  .page-about .about-paths {
    grid-template-columns: repeat(3, 1fr);
  }
  .page-about .about-path-bottom {
    grid-template-columns: 0.8fr 1.2fr 0.8fr;
    align-items: center;
  }
}

@media (min-width: 960px) {
  .page-about .about-flow {
    grid-template-columns: 1.3fr 0.75fr;
    align-items: start;
  }
  .page-about .about-flow-steps {
    grid-template-columns: repeat(5, 1fr);
    gap: 12px;
  }
  .page-about .about-flow-step:not(:last-child)::after {
    content: "";
    position: absolute;
    right: -9px;
    top: 50%;
    width: 7px;
    height: 7px;
    border-top: 2px solid var(--ink);
    border-right: 2px solid var(--ink);
    transform: rotate(45deg);
  }
}