#popup {
    width:700px;
    display:none;
    position:absolute;
    margin:0 auto;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 9999;
  }
  #close{
    font-size:30px; 
    padding-left:89%;
    padding-top:1%; 
    margin:auto;
    position: absolute;
  }
  
  @media (max-width:768px){
    #popup {
      width:350px;
    }
    #close{
      font-size:30px; 
      padding-left:94%;
      padding-top:1%; 
      margin:auto;
      position: absolute;
    }
    }