$(document).on('click', '.panel-heading .btn-clickable', function(e){
var $this = $(this);
if(!$this.hasClass('panel-collapsed')) {
$this.parents('.panel').find('.panel-body').slideUp();
$this.addClass('panel-collapsed');
$this.find('i').removeClass('fa-chevron-up').addClass('fa-chevron-down');
} else {
$this.parents('.panel').find('.panel-body').slideDown();
$this.removeClass('panel-collapsed');
$this.find('i').removeClass('fa-chevron-down').addClass('fa-chevron-up');
}
})