.btn {
    padding: .6rem 1rem;
    border-radius: .3rem;
    border: none;
    color: white;
}
.btn-red { background-color: red; }
.btn-green { background-color: green; }
.btn-blue { background-color: blue; }

.azul { color: blue; }
.rojo { color: red; }
.verde { color: green; }