/* --- generic utilities --- */
.empty {
  text-align: center;
  padding: 4rem 1rem;
  color: var(--color-muted);
}
.btn {
  display: inline-block;
  background: var(--color-fg);
  color: var(--color-bg);
  padding: calc(0.667em + 2px) calc(1.333em + 2px);
  border-radius: 8px;
  font-weight: 500;
  font-size: var(--fs-xs);
  transition: background .15s ease, color .15s ease, transform .15s ease;
}
.btn:hover { background: var(--color-accent); color: var(--color-bg); transform: translateY(-1px); }

/* --- responsive overrides --- */
@media (max-width: 640px) {
  .site-header__inner { padding: 0.85rem 1rem; }
  .site-main { padding-inline: 1rem; }
  /* hero, card-grid, etc. already shrink via --sp-* clamp tokens */
}