fix index.js

gistfile1.txt

$("#test_link").on("singletap", function(e) {

  	var a = '#test';
	$.UINavigationHistory[0] = a;
	$.UISetHashOnUrl(a);
	$('.button.slide-out-button').hide(); // hides that toggle button
	$('.slide-out').removeClass('open');
	$('article').removeClass('show');
	$('article').prev().removeClass('show');
	$(a).addClass('open');
	$(a).prev().addClass('show')
	
});

$("#back_to_music").on("singletap", function(e) {

  	var a = '#music';
	$.UINavigationHistory[0] = a;
	$.UISetHashOnUrl(a);
	$('.button.slide-out-button').show(); // hides that toggle button
	$('.slide-out').removeClass('open');
	$('article').removeClass('show');
	$('article').prev().removeClass('show');
	$(a).addClass('open');
	$(a).prev().addClass('show')
	
});

<nav style="text-align:left">
    	<a id="#back_to_music" ....