<button class="radikalwp-btn-sweep">خرید اشتراک<//button>

.radikalwp-btn-sweep {
  position: relative;
  padding: 13px 36px;
  font-family: inherit;
  font-size: 15px;
  font-weight: 800;
  color: #fff;
  background: linear-gradient(135deg, #059669, #10b981);
  border: none;
  border-radius: 12px;
  cursor: pointer;
  overflow: hidden;
  box-shadow: 0 8px 22px rgba(16, 185, 129, .35);
}
.radikalwp-btn-sweep::after {
  content: "";
  position: absolute;
  top: 0;
  left: -80%;
  width: 45%;
  height: 100%;
  background: linear-gradient(105deg, transparent, rgba(255, 255, 255, .45), transparent);
  transform: skewX(-20deg);
  animation: radikalwp-btn-sweep-shine 3.2s ease-in-out infinite;
}
@keyframes radikalwp-btn-sweep-shine {
  0%   { left: -80%; }
  55%  { left: 130%; }
  100% { left: 130%; }
}