Dynamic results from checkbox combinations in alphabetical order

I promise searched a lot, but didn't find anything that really answers.

I'd like to show a list of alphabetically ordered countries according to my combination of checked regions. So far I've been able to achieve this for individual regions, but not for combinations. See http://ift.tt/2fdosuI What I want is if, for example, I click the 'Europe' and 'Asia' checkboxes, I'd like to see the following checkboxes in a continuous alphabetically-ordered list: "Austria China Germany Japan Spain Thailand". Any other combination needs to work too. Is this possible?

Any help much appreciated

<label>
<input type="checkbox" name="colorCheckbox" id="Europe" />Europe</label>
<label>
<input type="checkbox" name="colorCheckbox" id="Africa" />Africa</label>
<label>
<input type="checkbox" name="colorCheckbox" id="Asia" />Asia</label>


<div class="mywrapper">

<div id="myEurope">
<label>
  <input type="checkbox" value="Spain" />Spain</label>
<label>
  <input type="checkbox" value="Germany" />Germany</label>
<label>
  <input type="checkbox" value="Austria" />Austria</label>
</div>

<div id="myAfrica">
<label>
  <input type="checkbox" value="Nigeria" />Nigeria</label>
<label>
  <input type="checkbox" value="Egypt" />Egypt</label>
<label>
  <input type="checkbox" value="Kenya" />Kenya</label>
</div>

<div id="myAsia">
<label>
  <input type="checkbox" value="Thailand" />Thailand</label>
<label>
  <input type="checkbox" value="China" />China</label>
<label>
  <input type="checkbox" value="Japan" />Japan</label>
</div>

</div>



$(function() {
$('input[type="checkbox"]').click(function() {

var sortByText = function(a, b) {
return $.trim($(a).text()) > $.trim($(b).text()); 
}

// --------------
if ($(this).attr("id") == "Europe") {
var sorted = $('#myEurope label').sort(sortByText);
$('#myEurope').append(sorted);
$("#myEurope").slideToggle(200)
}
// --------------
if ($(this).attr("id") == "Africa") {
var sorted = $('#myAfrica label').sort(sortByText);
$('#myAfrica').append(sorted);
$("#myAfrica").slideToggle(200)
}
// --------------
if ($(this).attr("id") == "Asia") {
var sorted = $('#myAsia label').sort(sortByText);
$('#myAsia').append(sorted);
$("#myAsia").slideToggle(200)
}
// --------------

});
});



.mywrapper {
border: 1px solid blue;
height: 200px;
width: 300px;
border: 1px solid blue;
}

#myEurope {
display: none;
}

#myAfrica {
display: none;
}

#myAsia {
display: none;
}