<button class="radikalwp-btn-stripe">در حال پردازش<//button>

.radikalwp-btn-stripe {
  padding: 12px 32px;
  font-family: inherit;
  font-size: 15px;
  font-weight: 700;
  color: #fff;
  background: repeating-linear-gradient(-45deg, #334155 0 12px, #1e293b 12px 24px);
  background-size: 200% 100%;
  border: none;
  border-radius: 12px;
  cursor: pointer;
  animation: radikalwp-stripe-move 1.4s linear infinite;
  transition: filter .25s ease;
}
@keyframes radikalwp-stripe-move {
  to { background-position: -34px 0; }
}
.radikalwp-btn-stripe:hover { filter: brightness(1.2); }