I believe within your initJScrollPane
function in the logic.frontend.js you have height being set with javascript after css is set:
var width = $('#elementsContainer ul').width();
var height = $('#elementsContainer ul').height();
$('#jScrollPane_Wrapper').css({'height' : height, 'width' : width});
$('#jScrollPane_Wrapper').jScrollPane({
height: 600
});
I think, this could be getting the height of the whole content(<ul>
), which is causing the wrong height to be set that you want.
Maybe changing it to this will fix it:
var height = $('#elementsContainer').height();
As that is set to 600px which I believe is what you are wanting it set too.