$('.gjs-trt-traits') is null (trying to have 'Settings' sector under the style)

Hi,
I'm using webpage preset and trying to have Settings sector under Style like the demo by doing this (exactly the same as demo.html) but the problem that i have is $('.gjs-trt-traits') this is null therefore, if I toggle 'Settings' under Styles, it is empty. Please let me know..Thank you!


    var traitsSector = $('<div class="gjs-sm-sector no-select">'+
    '<div class="gjs-sm-title"><span class="icon-settings fa fa-cog"></span> Settings</div>' +
    '<div class="gjs-sm-properties" style="display: none;"></div></div>');
    var traitsProps = traitsSector.find('.gjs-sm-properties');
    traitsProps.append($('.gjs-trt-traits'));
    $('.gjs-sm-sectors').before(traitsSector);
    traitsSector.find('.gjs-sm-title').on('click', function(){
      var traitStyle = traitsProps.get(0).style;
      var hidden = traitStyle.display == 'none';
      if (hidden) {
        traitStyle.display = 'block';
      } else {
        traitStyle.display = 'none';
      }