function make_active(button, yes_no){
	// get the link to the left, stored in a variable
	var parent_li = Element.ancestors(button)[0];
	var next_lis = Element.nextSiblings(parent_li);
	var prev_lis = Element.previousSiblings(parent_li);
	var left_link = 0;
	var right_link = 0;
	if(next_lis[0]){ left_link = next_lis[0].descendants()[0]; }
	if(prev_lis[0]){ right_link = prev_lis[0].descendants()[0]; }

	// if you want the button active
	if(yes_no==1){
		// if the link to the left is active
		if(Element.hasClassName(left_link, "active")){
			// add the hover_l_a class
			Element.addClassName(button, "hover_l_a");
		}	
		//otherwise
		else{	
			//add the hover_l_i class
			Element.addClassName(button, "hover_l_i");
		}
		
		// if the link to the right is active
		if(Element.hasClassName(right_link, "active")){
			// add the hover_r_a class
			Element.addClassName(right_link, "hover_r_a");
		}
		// otherwise
		else{
			// add the hover_r_i class
			Element.addClassName(right_link, "hover_r_i");
		}
	}
	// otherwise
	else{
		// remove all classes if they exist
		Element.removeClassName(button, "hover_l_a");
		Element.removeClassName(button, "hover_l_i");
		Element.removeClassName(right_link, "hover_r_a");
		Element.removeClassName(right_link, "hover_r_i");
	}
}

function activate_right_nav(){
	// grab the nav element that's active
	var active_nav = $$("#nav ul li a.active")[0];
	var parent_li = active_nav.ancestors()[0];
	var lis = parent_li.previousSiblings();
	var nav_to_activate = 0;

	// if parent has previous sibling
	if(lis[0]){		
		// grab it and add class name "l_a"
		nav_to_activate = lis[0].descendants()[0];		
		nav_to_activate.addClassName("l_a");
	}
}