body {
  background: #E0E0E0;
}

div {
  border: 2px solid #FFF;
  color: white;
  float: left;
  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
  height: 100px;
  margin: 0 2px;
  padding: 2rem;
  text-align: center;
  width: 100px;
}
div.base {
  background: #e74c3c;
}
div.secondary {
  background: #3ce74c;
}
div.tertiary {
  background: #4c3ce7;
}