.btn-navy {
  background-color: #003366;
  color: white;
  border: none;
}

.btn-navy:hover {
  background-color: white;
  color: #003366;
  outline-style: solid; /* or dotted, dashed, double, groove, ridge, inset, outset */
  outline-color: #003366; /* or a hex code, RGB, HSL value */
  outline-width: 2px;
}