$(document).ready(function() {
  $('.popup').click(function() {
    var self = $(this);
        url = self.attr('href');
        width = self.attr('data-width');
        height = self.attr('data-height');
        
    if(!width) {
      width = 596;
    }
    
    if(!height) {
      height = 850;
    }
    
    window.open(url,null,'scrollbars=1,width='+width+',height='+height);
    return false;
  });
});