.pm-insert-bibliography-source-panel-warning {
  background: #fdf5e0;
  border: solid 1px;
  border-radius: 3px;
  padding: 4px;
  text-align: center;
  margin-bottom: 4px;
  font-size: 8pt;
  font-weight: 1;
  opacity: 0.8; 
}