.

scripts/custom.js

 
     //service and industry
     
-        
-
    //homepage
    var previousLink;
    var indexPeviousSelectedLink = 0;
     $('#navigation .service-link').on('click', function()
     {
         
-        $(".nav-active-mark").parent().removeClass("active");
+        $(".nav-active-mark").parent().removeClass("active").removeClass('up');
         $(".nav-active-mark").remove();
         
         $('#industriesMenu').css('display', 'none');
             }
             else if(previousLink !== undefined)
             {
-                $(this).addClass('active').append('<span class="nav-active-mark"></span>');
+                $(this).addClass('active').addClass("up").append('<span class="nav-active-mark"></span>');
                 previousLink = 'services'
                 //$(this).remove('.nav-active-mark').removeClass('active'); 
-            }
-            
+            }           
           
         }
         else
         {
 
             $('#header').addClass('active_dropdown');
-            $(this).addClass('active').append('<span class="nav-active-mark"></span>');
+            $(this).addClass('active').addClass('up').append('<span class="nav-active-mark"></span>');
             previousLink = 'services';
         }
 
     $('#navigation .industries-link').on('click', function()
     {
         
-        $(".nav-active-mark").parent().removeClass("active");
+        $(".nav-active-mark").parent().removeClass("active").removeClass('up');
         $(".nav-active-mark").remove();
         
         $('#servicesMenu').css('display', 'none');
                 //$(this).remove('.nav-active-mark').removeClass('active');
 
                 backToPreviousLink();
-                  previousLink = '';
+                previousLink = '';
             }
             else if(previousLink !== undefined)
             {
                 //$(this).remove('.nav-active-mark').removeClass('active');
-                $(this).addClass('active').append('<span class="nav-active-mark"></span>');
+                $(this).addClass('up').addClass('active').append('<span class="nav-active-mark"></span>');
                 previousLink = 'industries'; 
             }
             
         else
         {
             $('#header').addClass('active_dropdown');
-            $(this).addClass('active').append('<span class="nav-active-mark"></span>');
+            $(this).addClass('up').addClass('active').append('<span class="nav-active-mark"></span>');
             previousLink = 'industries';
         }
 

styles/custom.css

     font-size: 17px;
     transition: transform .35s;
 }
-.service-link.active .fa-angle-down, .industries-link.active .fa-angle-down
+.service-link.up.active .fa-angle-down, .industries-link.up.active .fa-angle-down
 {
     transform: rotate(180deg);
 }