.toast {
  position: fixed;
  bottom: 20px;
  right: 20px;
  background: rgba(0,0,0,0.75);
  color: #fff;
  padding: 14px 22px;
  border-radius: 10px;
  font-size: 15px;
  z-index: 9999;
  opacity: 0;
  transform: translateY(10px);
  animation: toast-in 0.4s forwards, toast-out 0.4s 4s forwards;
}

.toast.success {
  background: rgba(38, 151, 88, 0.9); /* 緑系 */
}

.toast.error {
  background: rgba(200, 45, 45, 0.9); /* 赤系 */
}

@keyframes toast-in {
  from { opacity: 0; transform: translateY(10px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes toast-out {
  to   { opacity: 0; transform: translateY(10px); }
}