/* Hub topics browse — SPB-04 */
.topics-browse-page .site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  padding: 0.75rem 1.25rem;
  background: rgba(247, 253, 255, 0.94);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(8px);
}

.topics-hero {
  padding: 2.5rem 0 1rem;
  background:
    radial-gradient(circle at 10% 0%, rgba(27, 164, 184, 0.16), transparent 45%),
    linear-gradient(180deg, #eef8fb, transparent);
}

.topics-status {
  margin: 1rem 0 0;
  font-size: 0.95rem;
  color: var(--water);
  font-weight: 700;
}

.topics-filters {
  padding: 1rem 0 0.5rem;
}

.topics-filter-row {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.75rem;
}

.topics-filters label {
  display: grid;
  gap: 0.35rem;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--ink-soft);
}

.topics-filters select,
.topics-filters input {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 0.55rem 0.7rem;
  font: inherit;
  background: #fff;
  color: var(--ink);
}

.topics-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 0.9rem;
}

.topics-chip {
  border: 1px solid var(--line);
  background: #fff;
  color: var(--ink);
  border-radius: 999px;
  padding: 0.35rem 0.8rem;
  font-size: 0.82rem;
  font-weight: 700;
  cursor: pointer;
}

.topics-chip.is-active {
  background: var(--water);
  border-color: var(--water);
  color: #fff;
}

.topics-list-section {
  padding: 1rem 0 3rem;
}

.topics-list-title {
  margin: 0 0 0.75rem;
  font-size: 1.1rem;
}

.topics-list {
  display: grid;
  gap: 0.75rem;
}

.topics-item {
  display: grid;
  grid-template-columns: 7rem 1fr auto;
  gap: 0.9rem;
  align-items: start;
  padding: 1rem 1.1rem;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: #fff;
  text-decoration: none;
  color: inherit;
  box-shadow: var(--shadow);
  transition: transform 0.2s var(--ease), border-color 0.2s var(--ease);
}

.topics-item:hover {
  transform: translateY(-2px);
  border-color: rgba(14, 127, 159, 0.35);
}

.topics-meta {
  font-size: 0.78rem;
  color: var(--ink-soft);
  line-height: 1.45;
}

.topics-title {
  margin: 0 0 0.35rem;
  font-size: 1.02rem;
  font-family: var(--font-display);
}

.topics-desc {
  margin: 0;
  font-size: 0.9rem;
  color: var(--ink-soft);
}

.topics-go {
  align-self: center;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--primary-dark);
  white-space: nowrap;
}

.topics-empty,
.topics-loading,
.topics-error {
  padding: 1.25rem;
  border: 1px dashed var(--line);
  border-radius: 12px;
  color: var(--ink-soft);
}

.topics-browse-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  margin-top: 1rem;
  font-weight: 700;
  color: var(--primary-dark);
}

@media (max-width: 860px) {
  .topics-filter-row {
    grid-template-columns: 1fr 1fr;
  }
  .topics-item {
    grid-template-columns: 1fr;
  }
  .topics-go {
    justify-self: start;
  }
}