.popup .overlay {
  position:fixed;
  top:0px;
  left:0px;
  width:100vw;
  height:100vh;
  background:rgba(0,0,0,0.7);
  z-index:1;
  display:none;
}
 
.popup .content {
  position:absolute;
  top:50%;
  left:50%;
  transform:translate(-50%,-50%) scale(0);
  background:white;
  width:100%;
  height:450px;
  z-index:2;
  text-align:center;
  padding:20px;
  box-sizing:border-box;
  font-family:"Open Sans",sans-serif;
}
 
.popup .close-btn {
  cursor:pointer;
  position:absolute;
  right:20px;
  top:20px;
  width:30px;
  height:30px;
  background:#222;
  color:#fff;
  font-size:25px;
  font-weight:600;
  line-height:30px;
  text-align:center;
  border-radius:50%;
}
 
.popup.active .overlay {
  display:block;
}
 
.popup.active .content {
  transition:all 300ms ease-in-out;
  transform:translate(-50%,-50%) scale(1);
}