Joomla template with bootstrap4

For me and my sister i made a joomla template. I did have a problem with the menus. Joomla did not add the css class needed for bootstrap 4 to work. I found that the javascript below to added the needed css-classes.

$(document).ready(function(){
	$('#navbarSupportedContent>ul>li').addClass('nav-item');
	$('#navbarSupportedContent>ul>li>a').addClass('nav-link');
	$('#navbarSupportedContent>ul>li>ul').addClass('dropdown-menu');
	$('#navbarSupportedContent>ul>li>ul>li').addClass('dropdown-item');
	$('#navbarSupportedContent>ul>li>ul>li>a').addClass('dropdown-item');

	$('#navbarSupportedContent>ul>li>ul').each(function() {
		$( this ).parent().addClass('dropdown');
		$( this ).parent().find("a").first().addClass('dropdown-toggle');
		$( this ).parent().find("a").first().attr('data-toggle', 'dropdown');
		$( this ).parent().find("a").first().attr('role', 'button');
	});
});

Skills:

Autodesk Inventor, Vault, Git, C#, vb, .net, php HTML, css, js

Education:

University computer science.
HBO Mechanical engineer.
MBO Fine mechanics.

Experience:

Programmer and Mechanical engineer at Kelvion
(2016 - 20..)

Mechanical engineer at Strukton
(2009 - 2016)

Mechanical engineer at RDG-engineering
(2007 - 2009)

CNC Programmer at VMC
(2005 - 2007)

volunteer at Taizé
(2007)

Certifications:

Objectgeoriënteerd analyseren en ontwerpen, Objectgeoriënteerd programmeren in Java, Webapplicaties: de clientkant, Databases, Security Aware Programmer, Web Security Specialist