.page-topics {
  padding-bottom: var(--space-8);
}

/* ---------- 面包屑 ---------- */
.page-topics .topics-crumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-3) 0 var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink-soft);
}
.page-topics .topics-crumb a {
  color: var(--color-ink-soft);
  text-decoration: none;
  border-bottom: 1px dotted var(--color-line);
}
.page-topics .topics-crumb a:hover,
.page-topics .topics-crumb a:focus-visible {
  color: var(--color-primary);
  border-bottom-color: var(--color-primary);
}
.page-topics .topics-crumb__num {
  color: var(--color-primary);
}
.page-topics .topics-crumb [aria-current="page"] {
  color: var(--color-ink);
}

/* ---------- 首屏 ---------- */
.page-topics .topics-hero {
  padding: var(--space-4) 0 var(--section-y);
  border-bottom: 1px dotted var(--color-line);
}
.page-topics .hero-eyebrow {
  margin: 0 0 var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: var(--tracking-heading);
  color: var(--color-primary);
}
.page-topics .hero-title {
  margin: 0;
  font-family: var(--font-heading);
  font-size: var(--text-display);
  line-height: 0.94;
  font-weight: var(--weight-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
  overflow-wrap: anywhere;
}

.page-topics .hero-scale {
  display: flex;
  margin-top: var(--space-4);
  padding-top: calc(var(--space-1) / 2);
  border-top: 1px dotted var(--color-line);
  overflow-x: auto;
  scrollbar-width: none;
}
.page-topics .hero-scale::-webkit-scrollbar {
  display: none;
}
.page-topics .hero-scale span {
  position: relative;
  flex: 1 0 auto;
  min-width: calc(var(--space-6) - var(--space-1));
  padding-top: calc(var(--space-1) / 2);
  text-align: center;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink-muted);
}
.page-topics .hero-scale span::before {
  content: "";
  position: absolute;
  top: calc(var(--space-1) / -2);
  left: 50%;
  width: var(--border-thin);
  height: calc(var(--space-1) / 2);
  background: var(--color-line);
}

.page-topics .hero-body {
  display: grid;
  gap: var(--space-6);
  margin-top: var(--space-6);
  align-items: start;
}
.page-topics .hero-lede {
  margin: 0 0 var(--space-4);
  max-width: var(--measure);
  font-size: var(--text-lg);
  line-height: var(--leading-body);
  color: var(--color-ink);
}
.page-topics .hero-figures {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-3);
  margin: 0;
  padding: var(--space-3) 0 0;
  list-style: none;
  border-top: 1px dotted var(--color-line);
}
.page-topics .hero-figure__num {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-figure);
  line-height: 1;
  letter-spacing: var(--tracking-heading);
  color: var(--color-primary);
}
.page-topics .hero-figure__label {
  display: block;
  margin-top: var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink-soft);
}
.page-topics .hero-direct {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2);
  margin: var(--space-4) 0 0;
}
.page-topics .hero-direct__label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink-muted);
}
.page-topics .topics-copy {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: var(--tracking-heading);
  color: var(--color-primary);
  background: var(--color-primary-soft);
  border: var(--border-thin) solid var(--color-primary);
  border-radius: var(--radius-sm);
  padding: calc(var(--space-1) / 2) var(--space-1);
  cursor: pointer;
  transition: background-color 160ms linear, color 160ms linear;
}
.page-topics .topics-copy:hover,
.page-topics .topics-copy:focus-visible,
.page-topics .topics-copy[data-copied] {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  outline: none;
}

.page-topics .hero-right {
  display: grid;
  gap: var(--space-3);
}
.page-topics .hero-spine {
  display: flex;
  flex-direction: column;
  gap: calc(var(--space-1) / 4);
  min-height: 160px;
}
.page-topics .hero-spine__seg {
  flex: 1 1 0;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: var(--tracking-heading);
  background: var(--color-surface-alt);
  color: var(--color-ink-muted);
}
.page-topics .hero-spine__seg:nth-child(1) {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}
.page-topics .hero-spine__seg:nth-child(2) {
  background: var(--color-primary-soft);
  color: var(--color-primary);
}
.page-topics .hero-spine__seg:nth-child(3) {
  background: var(--color-highlight);
  color: var(--color-primary);
}
.page-topics .hero-spine__seg:nth-child(4) {
  background: var(--color-surface-deep);
  color: var(--color-ink-soft);
}
.page-topics .hero-spine__seg:nth-child(5) {
  background: var(--color-surface-alt);
  color: var(--color-ink-soft);
}
.page-topics .hero-figure-media {
  margin: 0;
  overflow: hidden;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  background: var(--color-surface-alt);
}
.page-topics .hero-figure-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

/* ---------- 分类筛选 ---------- */
.page-topics .topics-filter {
  margin-top: var(--section-y);
}
.page-topics .tf-input {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}
.page-topics .tf-bar {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  margin-bottom: var(--space-6);
  padding-bottom: var(--space-3);
  border-bottom: 1px dotted var(--color-line);
}
.page-topics .tf-pill {
  display: inline-block;
  padding: var(--space-1) var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink-soft);
  background: var(--color-surface-alt);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background-color 160ms linear, color 160ms linear, border-color 160ms linear;
}
.page-topics .tf-pill:hover {
  color: var(--color-primary);
  border-color: var(--color-primary);
}

.page-topics #tf-all:checked ~ .tf-bar label[for="tf-all"],
.page-topics #tf-1:checked ~ .tf-bar label[for="tf-1"],
.page-topics #tf-2:checked ~ .tf-bar label[for="tf-2"],
.page-topics #tf-3:checked ~ .tf-bar label[for="tf-3"],
.page-topics #tf-4:checked ~ .tf-bar label[for="tf-4"],
.page-topics #tf-5:checked ~ .tf-bar label[for="tf-5"] {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  border-color: var(--color-primary);
}

.page-topics #tf-1:checked ~ .cat-stack .topic-cat:not([data-cat="1"]),
.page-topics #tf-2:checked ~ .cat-stack .topic-cat:not([data-cat="2"]),
.page-topics #tf-3:checked ~ .cat-stack .topic-cat:not([data-cat="3"]),
.page-topics #tf-4:checked ~ .cat-stack .topic-cat:not([data-cat="4"]),
.page-topics #tf-5:checked ~ .cat-stack .topic-cat:not([data-cat="5"]) {
  display: none;
}

/* ---------- 分类区块 ---------- */
.page-topics .cat-stack {
  display: flex;
  flex-direction: column;
  gap: var(--section-y);
}
.page-topics .cat-head {
  display: grid;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
  padding-top: var(--space-3);
  border-top: var(--border-thin) dotted var(--color-line);
}
.page-topics .cat-head__num {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: var(--tracking-heading);
  color: var(--color-primary);
}
.page-topics .cat-head__title {
  position: relative;
  margin: var(--space-1) 0 0;
  font-family: var(--font-heading);
  font-size: var(--text-xl);
  line-height: var(--leading-heading);
  font-weight: var(--weight-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}
.page-topics .cat-head__title::before {
  content: "";
  display: inline-block;
  width: calc(var(--space-2) + var(--space-1));
  height: 0.72em;
  margin-right: var(--space-2);
  vertical-align: -0.02em;
  background: linear-gradient(
    90deg,
    var(--color-primary) 0%,
    var(--color-primary) 48%,
    var(--color-highlight) 48%,
    var(--color-highlight) 100%
  );
  clip-path: polygon(0 0, 100% 0, 78% 100%, 0 100%);
}
.page-topics .cat-head__note {
  margin: var(--space-2) 0 0;
  max-width: var(--measure);
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}
.page-topics .cat-head__media {
  margin: 0;
  overflow: hidden;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  background: var(--color-surface-alt);
}
.page-topics .cat-head__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}
.page-topics .cat-head__media--wide img {
  aspect-ratio: 16 / 9;
}
.page-topics .cat-head__media--panorama img {
  aspect-ratio: 2 / 1;
}
.page-topics .cat-head__media--tall img {
  aspect-ratio: 3 / 2;
}

/* ---------- 条目列表 ---------- */
.page-topics .topic-list {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: var(--border-thin) dotted var(--color-line);
}
.page-topics .topic-item {
  border-bottom: var(--border-thin) dotted var(--color-line);
}
.page-topics .topic-item__row {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  grid-template-areas:
    "num tag"
    "body body";
  gap: var(--space-2);
  align-items: center;
  padding: var(--space-3) var(--space-2);
  transition: background-color 160ms linear;
}
.page-topics .topic-item__row:hover {
  background: var(--color-surface-alt);
}
.page-topics .topic-item__num {
  grid-area: num;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: var(--tracking-heading);
  color: var(--color-primary);
}
.page-topics .topic-item__body {
  grid-area: body;
}
.page-topics .topic-item__title {
  margin: 0;
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  line-height: var(--leading-heading);
  font-weight: var(--weight-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}
.page-topics .topic-item__desc {
  margin: var(--space-1) 0 0;
  max-width: var(--measure);
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}
.page-topics .topic-tag {
  grid-area: tag;
  justify-self: start;
  padding: calc(var(--space-1) / 2) var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: var(--tracking-heading);
  white-space: nowrap;
  color: var(--color-ink-soft);
  background: transparent;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  transition: background-color 160ms linear, color 160ms linear, border-color 160ms linear;
}
.page-topics .topic-tag--on {
  color: var(--color-primary);
  border-color: var(--color-primary);
}
.page-topics .topic-tag--accent {
  color: var(--color-primary-ink);
  background: var(--color-accent);
  border-color: var(--color-accent);
}
.page-topics .topic-item__row:hover .topic-tag {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  border-color: var(--color-primary);
}
.page-topics .topic-item__row:hover .topic-tag--on {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}

.page-topics .topics-link {
  color: var(--color-primary);
  text-decoration: none;
  border-bottom: var(--border-thin) dotted var(--color-primary);
}
.page-topics .topics-link:hover,
.page-topics .topics-link:focus-visible {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  border-bottom-color: transparent;
  outline: none;
}

.page-topics .topics-link:focus-visible,
.page-topics .tf-pill:focus-visible {
  outline: var(--border-thin) solid var(--color-focus);
  outline-offset: calc(var(--space-1) / 4);
}

/* ---------- 响应式 ---------- */
@media (min-width: 620px) {
  .page-topics .hero-right {
    grid-template-columns: calc(var(--space-8) - var(--space-1)) minmax(0, 1fr);
    align-items: stretch;
  }
  .page-topics .hero-spine {
    min-height: 0;
  }
}

@media (min-width: 760px) {
  .page-topics .topic-item__row {
    grid-template-columns: calc(var(--space-8) + var(--space-1)) minmax(0, 1fr) calc(var(--space-8) + var(--space-6) + var(--space-2));
    grid-template-areas: "num .page-topics tag";
    align-items: baseline;
    gap: var(--space-3);
    padding: var(--space-3) var(--space-3);
  }
  .page-topics .topic-tag {
    justify-self: end;
  }
}

@media (min-width: 900px) {
  .page-topics .hero-body {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: var(--space-8);
  }
  .page-topics .hero-figures {
    gap: var(--space-4) var(--space-3);
  }
  .page-topics .cat-head {
    grid-template-columns: minmax(0, 1fr) calc(var(--container) / 3.4);
    align-items: center;
    gap: var(--space-6);
  }
  .page-topics .cat-head--text-only {
    grid-template-columns: minmax(0, 1fr);
  }
  .page-topics .cat-head__media {
    align-self: start;
  }
}
<<<END>>>