Just a little snippet to check for segments in the url and add a switch statement to add classes.

segment_via_js

$(document).ready (function() {

  	// Get segments and store in variables
	var newURL = window.location.protocol + "://" + window.location.host + "/" + window.location.pathname;
	var pathArray = window.location.pathname.split( '/' );
	var segment_1 = pathArray[1];
    
	// switch cases depending on the url segment and add an active class

	switch (segment_1){
	
		case "your_segment_value":
	    	$("selector").addClass("active"); // do something
		break; 
		
		case "your_other_segment_value":
		$("#step2").addClass("active") // do something else
		break;
		
	};

});