jQuery - Add class to an element based on URL

The if statement targets the URL

Add an ID to the target you want to add the class to,
Then enter it into the following line, alongside the name of the class you want:
"jQuery('#ID-NAME').addClass('CLASS-NAME');"

<!-- CODE TO USE IS BELOW -->

jQuery(function() {
  var loc = window.location.href; // returns the full URL
  if(/YOUR-URL/.test(loc)) {
    jQuery('#ID-NAME').addClass('CLASS-NAME');
  }
});