Bootstrap3垂直收缩手风琴代码

只用了少量的js代码
$(document).ready(function() {
	  $('.collapse.in').prev('.panel-heading').addClass('active');
	  $('#accordion, #bs-collapse')
		.on('show.bs.collapse', function(a) {
		  $(a.target).prev('.panel-heading').addClass('active');
		})
		.on('hide.bs.collapse', function(a) {
		  $(a.target).prev('.panel-heading').removeClass('active');
		});
	});