var wrapperHeight, navHeight, yPosWrapper;

function centradoVertical() {
	wrapperHeight = $('#wrapper').height();
	navHeight = $(window).height();
	yPosWrapper = Math.max( (navHeight - wrapperHeight) / 2, 0);
	
	$('#wrapper').css("margin-top", yPosWrapper+"px");

}

$(document).ready( function() {
  
  centradoVertical();
  
  $(window).resize( function() {
    centradoVertical();

  });
  
});