<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script>
jQuery(document).ready(function(){
jQuery('#btnSubmit').on('click', function() {
jQuery(this).addClass('toggle').removeClass('codepen');
});
});
</script>
According To Question:
#jQuery add remove class onclick codepen
#Add Class jQuery
#jQuery Onclick Remove Class And Addclass
#toggle class jQuery
#Onclick Add And Remove Class To Body
#Add Class JavaScript
#jQuery Add Class On Click
#Remove Class In JavaScript
#Add Remove Class Onclick By jQuery