body:before {
  content: "Kleiner 576";
  position: fixed;
  left: 10px;
  bottom: 10px;
  width: auto;
  border: 2px solid #0019a5;
  background: rgba(255,255,255,0.5);
  color: #000000;
  z-index: 10000;
  padding: 5px 10px;
  font-size: 14px;
}
@media (min-width: 576px) {
  body:before {
    content: "SM: ab 576px"; } }
@media (min-width: 768px) {
  body:before {
    content: "MD: ab 768px"; } }
@media (min-width: 992px) {
  body:before {
    content: "LG: ab 992px"; } }
@media (min-width: 1200px) {
  body:before {
    content: "XL: ab 1200px"; } }