.btn-margin {
  margin: 2px 10px;
  font-size: 2vw;
  padding: 1px;
  text-align: center;
}
/* Small devices (tablets, 768px and up) */
  @media (min-width: 768px) {
    .btn-margin {
      font-size: 1vw;
    }
 }
 /* Small devices (tablets, 768px and up) */
  @media (min-width: 970px) {
    .btn-margin {
      margin: 5px 10px;
      padding: 5px;
      font-size: 14px;
    }
 }