diff --git a/nix/pkgs/subnetplan/render.rb b/nix/pkgs/subnetplan/render.rb
index 68fb9fb..47211c8 100644
--- a/nix/pkgs/subnetplan/render.rb
+++ b/nix/pkgs/subnetplan/render.rb
@@ -57,7 +57,7 @@ nets.each do |net|
 end
 exit 1 if collisions > 0
 
-GROUP_PREFIX = 16
+GROUP_PREFIX = 19
 groups = {}
 nets.each do |net|
   group = net.addr.supernet(GROUP_PREFIX).to_s
@@ -101,7 +101,9 @@ def background_color desc
     "#9F9F9F"
   when "mgmt"
     "#FF3F3F"
-  when "c3d2"
+  when "roof"
+    "#FF4F2F"
+  when "c3d2", "flpk"
     "yellow"
   when "serv", "cluster"
     "orange"