Change text colour for active item

app/config/sculpin_site.yml

@@ -7,11 +7,14 @@ papercall:
     url: https://www.papercall.io/drupalcamp-bristol-2019
 
 main_menu:
-  - title: Tickets
-    url: '%eventbrite.url%'
+    - title: Tickets
+      url: '%eventbrite.url%'
+      pattern: ~
 
-  - title: Submit a session
-    url: '%papercall.url%'
+    - title: Submit a session
+      url: '%papercall.url%'
+      pattern: ~
 
-  - title: Sponsor us
-    url: /sponsor-us
+    - title: Sponsor us
+      url: /sponsor-us
+      pattern: /^\/sponsor-us\/?/