<button class="radikalwp-btn-neonpulse">شروع بازی<//button>

.radikalwp-btn-neonpulse {
  padding: 13px 36px;
  font-family: inherit;
  font-size: 15px;
  font-weight: 700;
  color: #e9d5ff;
  background: #14082e;
  border: 1.5px solid #a855f7;
  border-radius: 12px;
  cursor: pointer;
  box-shadow: 0 0 12px rgba(168, 85, 247, .45), inset 0 0 8px rgba(168, 85, 247, .18);
  animation: radikalwp-neonpulse-glow 2.2s ease-in-out infinite;
  transition: background .3s ease;
}
.radikalwp-btn-neonpulse:hover { background: #1e0b45; }
@keyframes radikalwp-neonpulse-glow {
  0%, 100% { box-shadow: 0 0 10px rgba(168, 85, 247, .35), inset 0 0 6px rgba(168, 85, 247, .15); }
  50%      { box-shadow: 0 0 22px rgba(168, 85, 247, .75), inset 0 0 12px rgba(168, 85, 247, .3); }
}