<a href="/buttons/9"><button class="bn9"><span>Button</span></button></a>

.bn9 {
  padding: 2px;
  outline: 0;
  font-size: 17px;
  color: rgb(0, 0, 0);
  background: -webkit-gradient(
    linear,
    left top,
    right top,
    from(#fdde5c),
    color-stop(#f8ab5e),
    color-stop(#f56a62),
    color-stop(#a176c8),
    color-stop(#759beb),
    color-stop(#65beb3),
    to(#70db96)
  );
  background: linear-gradient(
    to right,
    #fdde5c,
    #f8ab5e,
    #f56a62,
    #a176c8,
    #759beb,
    #65beb3,
    #70db96
  );
  border-radius: 30px;
  border: 0;
  box-shadow: none;
  cursor: pointer;
}

.bn9 > span {
  display: block;
  padding: 10px 40px;
  font-size: 17px;
  font-weight: 500;
  background: #ebebeb;
  border-radius: 30px;
}