@media (max-width: 499px) {
  body {
    background-color: green;
  }
}

@media (min-width: 500px) and (max-width: 800px) {
  body {
    background-color: red;
  }
}
@media (min-width: 801px) {
  body {
    background-color: blue;
  }
}

