/* ============================================================
   专题聚合 /topics/ —— 页面作用域 .page-topics
   ============================================================ */

.page-topics {
  display: block;
  background: var(--color-surface);
}

.page-topics a:focus-visible,
.page-topics button:focus-visible {
  outline: 3px solid var(--color-focus);
  outline-offset: 2px;
}

/* ---------- 首屏刊头 ---------- */

.page-topics .topics-hero {
  padding: var(--space-3) 0 var(--space-6);
}

.page-topics .topics-hero .breadcrumb {
  margin-bottom: var(--space-2);
}

.page-topics .topics-hero__frame {
  position: relative;
  display: flex;
  align-items: flex-end;
  min-height: 380px;
  padding: var(--space-6) var(--space-3) var(--space-4);
  overflow: hidden;
  border-radius: var(--radius-md);
  background: var(--color-contrast-surface);
  box-shadow: var(--shadow-2);
}

.page-topics .topics-hero__media {
  position: absolute;
  inset: 0;
}

.page-topics .topics-hero__media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.5) contrast(1.06);
}

.page-topics .topics-hero__scrim {
  position: absolute;
  inset: 0;
  background: var(--overlay-scrim);
}

.page-topics .topics-hero__frame::after {
  content: "";
  position: absolute;
  inset: var(--space-2);
  border: 1px dashed color-mix(in srgb, var(--color-contrast-ink) 32%, transparent);
  border-radius: var(--radius-sm);
  pointer-events: none;
  z-index: 2;
}

.page-topics .topics-hero__body {
  position: relative;
  z-index: 3;
  width: 100%;
  max-width: 46rem;
}

.page-topics .topics-hero .kicker {
  color: var(--color-contrast-accent);
  letter-spacing: 0.16em;
}

.page-topics .topics-hero__title {
  margin: var(--space-1) 0 0;
  font-family: var(--font-heading);
  font-size: var(--text-display);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-contrast-ink);
}

.page-topics .topics-hero__lede {
  margin: var(--space-2) 0 0;
  max-width: var(--measure);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-contrast-ink);
  opacity: 0.86;
}

.page-topics .topics-hero__stats {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4) var(--space-6);
  margin: var(--space-4) 0 0;
  padding-top: var(--space-3);
  border-top: 1px dashed color-mix(in srgb, var(--color-contrast-ink) 30%, transparent);
}

.page-topics .topics-hero__stat {
  display: flex;
  flex-direction: column;
  gap: calc(var(--space-1) / 2);
}

.page-topics .topics-hero__stat dt {
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  color: var(--color-contrast-ink);
  opacity: 0.72;
}

.page-topics .topics-hero__stat dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--text-figure);
  line-height: 1;
  color: var(--color-contrast-accent);
}

/* ---------- 索引尺 ---------- */

.page-topics .topics-index {
  padding-bottom: var(--space-4);
}

.page-topics .topics-ruler {
  border-top: 1px dashed var(--color-line);
  padding-top: var(--space-3);
  overflow-x: auto;
  overscroll-behavior-inline: contain;
  scrollbar-width: thin;
}

.page-topics .topics-ruler__list {
  display: flex;
  align-items: flex-start;
  gap: var(--space-6);
  min-width: max-content;
  margin: 0;
  padding: 0 0 var(--space-1);
  list-style: none;
}

.page-topics .topics-ruler__item {
  display: grid;
  gap: calc(var(--space-1) / 2);
  justify-items: start;
}

.page-topics .topics-ruler__node {
  display: block;
  color: var(--color-primary);
}

.page-topics .topics-ruler__label {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  color: var(--color-ink);
}

.page-topics .topics-ruler__count {
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  color: var(--color-ink-muted);
}

.page-topics .topics-switch {
  margin-top: var(--space-4);
  padding-top: var(--space-3);
  border-top: 1px dashed var(--color-line);
}

.page-topics .topics-switch .segmented {
  display: flex;
  flex-wrap: wrap;
  gap: calc(var(--space-1) / 2);
}

/* ---------- 专题方向区 ---------- */

.page-topics .topics-lane {
  position: relative;
  padding: var(--space-6) 0;
  border-top: 1px dashed var(--color-line);
}

.page-topics .topics-lane::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: var(--space-6);
  height: 2px;
  background: var(--color-accent);
}

.page-topics .topics-lane__head {
  display: grid;
  gap: var(--space-2);
  max-width: var(--measure);
  margin-bottom: var(--space-4);
}

.page-topics .topics-lane__title {
  margin: 0;
  font-family: var(--font-heading);
  font-size: clamp(var(--text-xl), 4.4vw, var(--text-3xl));
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

.page-topics .topics-lane__intro {
  margin: 0;
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-topics .topics-lane__body {
  display: grid;
  gap: var(--space-4);
  align-items: start;
}

/* ---------- 专题卡 ---------- */

.page-topics .topic-card {
  position: relative;
  padding: var(--space-4) var(--space-3) var(--space-3);
  background: var(--color-surface);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-2);
}

.page-topics .topic-card--alt {
  background: var(--color-surface-alt);
}

.page-topics .topic-card--deep {
  background: var(--color-surface-deep);
}

.page-topics .topic-tag {
  position: absolute;
  top: calc(-1 * var(--space-1));
  right: var(--space-3);
  z-index: 2;
  padding: calc(var(--space-1) / 2) var(--space-1);
  border-radius: var(--radius-sm);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  white-space: nowrap;
  background: var(--color-primary-soft);
  color: var(--color-ink);
  box-shadow: var(--shadow-1);
}

.page-topics .topic-tag--accent {
  background: var(--color-accent);
  color: var(--color-accent-ink);
}

.page-topics .topic-tag--primary {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}

.page-topics .topic-tag--highlight {
  background: var(--color-highlight);
  color: var(--color-ink);
}

.page-topics .topic-tag--tilt {
  transform: rotate(-3.2deg);
}

.page-topics .topic-tag--tilt-alt {
  transform: rotate(2.4deg);
}

.page-topics .topic-card__head {
  display: flex;
  align-items: baseline;
  gap: var(--space-2);
  margin-bottom: var(--space-2);
}

.page-topics .topic-card__ord {
  flex: none;
  min-width: var(--space-3);
  padding: calc(var(--space-1) / 2) 0;
  text-align: center;
  font-size: var(--text-xs);
  line-height: 1;
  background: var(--color-primary-soft);
  color: var(--color-ink);
  border-radius: var(--radius-sm);
}

.page-topics .topic-card__title {
  margin: 0;
  font-family: var(--font-heading);
  font-size: var(--text-xl);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  color: var(--color-ink);
}

.page-topics .topic-card__lede {
  margin: 0 0 var(--space-3);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-topics .topic-points {
  display: grid;
  gap: var(--space-2);
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-topics .topic-points > li {
  display: grid;
  grid-template-columns: var(--space-3) minmax(0, 1fr);
  gap: var(--space-1);
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-topics .topic-points .num {
  align-self: start;
  margin-top: calc(var(--space-1) / 4);
  padding: calc(var(--space-1) / 4) 0;
  text-align: center;
  font-size: var(--text-xs);
  line-height: 1.4;
  background: var(--color-primary-soft);
  color: var(--color-ink);
  border-radius: var(--radius-sm);
}

.page-topics .topic-card__foot {
  margin: var(--space-3) 0 0;
  padding-top: var(--space-2);
  border-top: 1px dashed var(--color-line);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
}

.page-topics .topic-card__foot a {
  color: var(--color-primary);
  text-decoration: none;
  border-bottom: 1px dashed currentColor;
}

.page-topics .topic-card__foot a:hover {
  color: var(--color-focus);
}

/* ---------- 卡片内图文 ---------- */

.page-topics .topic-card__split {
  display: grid;
  gap: var(--space-3);
}

.page-topics .topic-figure {
  margin: 0;
  overflow: hidden;
  border-radius: var(--radius-sm);
  background: var(--color-surface-deep);
  box-shadow: var(--shadow-1);
}

.page-topics .topic-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.55) contrast(1.04);
}

.page-topics .topic-figure--sm {
  max-width: 22rem;
  margin: var(--space-3) 0 0 auto;
}

/* ---------- 通栏视觉横幅 ---------- */

.page-topics .topics-banner {
  margin: 0 0 var(--space-4);
  overflow: hidden;
  border-radius: var(--radius-md);
  background: var(--color-surface-deep);
  box-shadow: var(--shadow-2);
}

.page-topics .topics-banner img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  aspect-ratio: 2 / 1;
  object-fit: cover;
  filter: saturate(0.5);
}

.page-topics .topics-banner__caption {
  padding: var(--space-2) var(--space-3);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
  background: var(--color-surface-alt);
}

/* ---------- 延伸入口 ---------- */

.page-topics .topics-outro {
  margin-top: var(--space-6);
  padding: var(--space-8) 0;
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.page-topics .topics-outro__inner {
  display: grid;
  gap: var(--space-3);
  max-width: var(--measure);
}

.page-topics .topics-outro .kicker {
  color: var(--color-contrast-accent);
  letter-spacing: 0.16em;
}

.page-topics .topics-outro__title {
  margin: 0;
  font-family: var(--font-heading);
  font-size: clamp(var(--text-xl), 4.4vw, var(--text-3xl));
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  color: var(--color-contrast-ink);
}

.page-topics .topics-outro__lede {
  margin: 0;
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-contrast-ink);
  opacity: 0.84;
}

.page-topics .topics-outro__links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-top: var(--space-2);
}

.page-topics .topics-jump {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 var(--space-3);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  letter-spacing: 0.06em;
  text-decoration: none;
  background: var(--color-contrast-ink);
  color: var(--color-contrast-surface);
  box-shadow: var(--shadow-2);
  transition: transform 160ms ease;
}

.page-topics .topics-jump:hover,
.page-topics .topics-jump:focus-visible {
  transform: translateY(-2px);
}

.page-topics .topics-jump--accent {
  background: var(--color-contrast-accent);
  color: var(--color-contrast-surface);
}

.page-topics .topics-outro__note {
  margin: 0;
  padding-top: var(--space-2);
  border-top: 1px dashed var(--color-contrast-line);
  font-size: var(--text-xs);
  line-height: var(--leading-body);
  letter-spacing: 0.04em;
  color: var(--color-contrast-ink);
  opacity: 0.72;
}

/* ---------- 平板与桌面 ---------- */

@media (min-width: 48em) {
  .page-topics .topics-hero {
    padding-top: var(--space-4);
    padding-bottom: var(--space-8);
  }

  .page-topics .topics-hero__frame {
    min-height: 460px;
    padding: var(--space-8) var(--space-6) var(--space-6);
  }

  .page-topics .topics-lane__body {
    grid-template-columns: repeat(12, minmax(0, 1fr));
  }

  .page-topics .topic-card--wide {
    grid-column: span 12;
  }

  .page-topics .topic-card--half {
    grid-column: span 6;
  }

  .page-topics .topic-card--drop {
    margin-top: var(--space-8);
  }

  .page-topics .topic-card__split {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    align-items: start;
    gap: var(--space-4);
  }

  .page-topics .topic-card__split--reverse {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }

  .page-topics .topic-card__split--reverse > .topic-figure {
    order: 2;
  }
}

@media (min-width: 64em) {
  .page-topics .topics-ruler__list {
    gap: var(--space-8);
  }

  .page-topics .topics-hero__frame::after {
    inset: var(--space-3);
  }
}

/* ---------- 动效收敛 ---------- */

@media (prefers-reduced-motion: reduce) {
  .page-topics .topics-jump {
    transition: none;
  }

  .page-topics .topics-jump:hover,
  .page-topics .topics-jump:focus-visible {
    transform: none;
  }

  .page-topics .topic-card--drop,
  .page-topics .topic-figure--sm {
    margin-top: var(--space-3);
  }
}
<<<END>>>