body {
  font-family: sans-serif;
}
.popup-overlay {
  position: fixed;
  top: 0; left: 0;
  width: 100%; height: 100%;
  background: rgba(0,0,0,0.5);
  display: none;
  justify-content: center;
  align-items: center;
  z-index: 1000;
}
.popup {
  position: relative;
  border-radius: 10px;
  width: 90%;
  max-width: 400px;
  text-align: center;
  animation: fadeIn 0.3s ease-out;
}
.popup img{
  width: 100%;
}
.popup .close-btn {
  position: absolute;
  top: 10px;
  right: 10px;
  background: #fff;
  border: 1px solid #ccc;
  border-radius: 50%;
  width: 38px;
  height: 38px;
  font-size: 25px;
  line-height: 28px;
  cursor: pointer;
}
@media (max-width: 480px) {
  .popup {
    width: 90%;
    padding: 15px;
    font-size: 14px;
  }
}
@media (min-width: 481px) and (max-width: 768px) {
  .popup {
    width: 80%;
    font-size: 15px;
  }
}
@media (min-width: 769px) {
  .popup {
    width: 70%;
    max-width: 400px;
    font-size: 16px;
  }
}
@keyframes fadeIn {
  from { opacity: 0; transform: scale(0.9);}
  to { opacity: 1; transform: scale(1);}
}