body {
  background-color: #f5f6f8;
}

.alert-stack .alert + .alert {
  margin-top: 0.5rem;
}

.topic-suggestions .btn {
  border-radius: 999px;
}

.topic-tree,
.topic-tree ul {
  list-style: none;
  padding-left: 1.2rem;
}

.topic-tree > li {
  margin-bottom: 0.75rem;
}

.topic-tree .tree-node {
  padding: 0.35rem 0.5rem;
  background: #fff;
  border-radius: 0.35rem;
  border: 1px solid rgba(0, 0, 0, 0.1);
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  cursor: pointer;
  transition: background-color 0.2s ease;
}

.topic-tree .tree-node:hover {
  background-color: #e7f1ff;
}

.topic-tree li.collapsed > ul {
  display: none;
}

.topic-tree li.collapsed > .tree-node::after {
  content: ' (collapsed)';
  font-size: 0.75rem;
  color: #6c757d;
}

.footer {
  position: sticky;
  top: 100%;
}

.favorite-toggle {
  font-size: 1.5rem;
  color: #f1b722;
  line-height: 1;
}

.favorite-toggle:hover,
.favorite-toggle:focus {
  text-decoration: none;
  color: #d48b00;
}

.favorite-toggle.btn-link {
  text-decoration: none;
}

.table-warning {
  transition: background-color 0.2s ease;
}