body::after {
  content: "Desktop";
  color: red;
}
@media (max-width: 992px) {
  body::after {
    content: "Tablet";
    color: royalblue;
  }
}
@media (max-width: 576px) {
  body::after {
    content: "Mobile";
    color: green;
  }
}

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