.popup-overlay {
  position: fixed;
  top: 0; left: 0;
  width: 100%; height: 100%;
  background-color: rgba(0,0,0,0.7);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 9999;
}

.popup-content {
  position: relative;
  width: 40%;
  background: transparent;
  padding: 0;
  display: flex;
  justify-content: center;
  align-items: center;
}

.popup-content img {
  width: 100%;
  height: auto;
  display: block;
}

.close-btn {
  position: absolute;
  top: -10px; right: -10px;
  font-size: 25px;
  background: #fff;
  color: #000;
  border-radius: 50%;
  width: 30px;
  height: 30px;
  line-height: 30px;
  text-align: center;
  cursor: pointer;
}

@media (max-width: 768px) {
  .popup-content { width: 80%; }
}