.copy-btn {
  position: absolute;
  top: 0.5rem;
  right: 0.5rem;
  background: rgba(255,255,255,0.9);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: 0.3rem 0.5rem;
  font-size: 0.7rem;
  cursor: pointer;
  opacity: 0;
  transition: opacity 0.15s;
  font-family: var(--font-body);
  color: var(--color-muted);
}
pre:hover .copy-btn { opacity: 1; }
.copy-btn.copied {
  color: var(--color-success);
  border-color: var(--color-success);
}