.popup {
  position: fixed;
  right: 0;
  top: 0;
  width: 210px;
  height: 100%;
  display: flex;
  justify-content: flex-start;
  align-items: center;
  visibility: hidden;
  opacity: 0;
  transition: visibility 0s, opacity 0.5s;
  z-index: 1000;}
.popup-content {
  position: relative;
  margin-right: 45px;}
.popup-content img {
  display: block;
  max-width: 100%;
  height: auto;}
.close-btn {
  position: absolute;
  right: 0; /* Cambiado de 'left' a 'right' */
  top: -5px;
  height: 30px;
  font-size: 25px;
  cursor: pointer;
  z-index: 10000;
  padding: 0 5px;}
.popup.active {
  visibility: visible;
  opacity: 1;}

@media screen and (max-width: 1800px) {
  .popup {
    width: 150px;}
  .popup-content {
    margin-right: 22px;}
  .close-btn {
    height: 24px;
    font-size: 20px;}
}

@media screen and (max-width: 1680px) {
  .popup {
    width: 110px;}
  .popup-content {
    margin-right: 10px;}
  .close-btn {
    top: -2px;
    height: 20px;
    font-size: 15px;}
}

@media screen and (max-width: 740px) {
  .popup {
      display: none; 
  }
}