Ultraviolet

.btn-ultraviolet {
  display: inline-block;
  padding: 12px 28px;
  border: none;
  border-radius: 12px;
  background: #7c3aed;
  color: #ffffff;
  font-family: inherit;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  box-shadow: 0 0 0 3px rgba(124, 58, 237, 0.35), 0 0 0 6px rgba(124, 58, 237, 0.15), 0 0 20px rgba(124, 58, 237, 0.6);
  transition: box-shadow 0.25s ease;
}
.btn-ultraviolet:hover {
  box-shadow: 0 0 0 5px rgba(124, 58, 237, 0.4), 0 0 0 10px rgba(124, 58, 237, 0.18), 0 0 32px rgba(124, 58, 237, 0.8);
}
.btn-ultraviolet:active {
  box-shadow: 0 0 0 2px rgba(124, 58, 237, 0.4), 0 0 14px rgba(124, 58, 237, 0.6);
}