.mfp-content{
 width: auto !important;
}
.mfp-iframe-holder .mfp-content{
 width: 100% !important;
}
.umc-fixed-popup {
  position: relative;
  background: #FFF;
  padding: 20px;
  width: 500px;
  margin: 20px auto;
}
.umc-fixed-popup img{
    width:100%;
}
.mfp-content img{
    max-width: 1000px; 
    width: 100%;
}  
.umc-flex-popup {
  /*text-align: center;*/
}
@media only screen and (max-width:766px){
    .umc-fixed-popup {
      max-width: 500px;
      width: 100%;
    }
    .mfp-content{
     width: 100% !important;
    }
}