Hi Remco,

Just add to custom.css file

.class2 .sp-module .sp-module-title {
  text-transform: uppercase;
  padding: 15px;
  color: #fff;
  background: #444;
  border-left: 6px solid #004e66;
}
.class2 .sp-module-content {
  padding: 10px;
  background: #fff;
  border: 1px solid #dddddd;
}