@keyframes shake {
  0%, 100% { transform: translateX(0); }
  20%, 60% { transform: translateX(-5px); }
  40%, 80% { transform: translateX(5px); }
}

.input-erro {
  border: 2px solid #ff4d4d !important;
  animation: shake 0.3s ease;
  box-shadow: 0 0 8px #ff4d4d;
}