body {
  font-family: Helvetica, sans-serif;
}

div.bright {
  border: 5px solid red;
}

.show-phablet, .show-tablet {
  display: none;
}

.hide-phablet, .hide-tablet {
  display: block;
}

/* Larger than phablet */
@media (min-width: 550px) {
  .show-phablet {
    display: block;
  }

  .hide-phablet {
    display: none;
  }
}

/* Larger than tablet */
@media (min-width: 750px) {
  .show-tablet {
    display: block;
  }

  .hide-tablet {
    display: none;
  }
}