move Scene code into a class

project_name/DefaultScene.cs

@@ -0,0 +1,20 @@
+using Nez;
+using Nez.ImGuiTools;
+
+namespace project_name
+{
+    public class DefaultScene : Scene
+    {
+        public override void initialize()
+        {
+            setDesignResolution( Screen.width, Screen.height, Scene.SceneResolutionPolicy.None );
+
+            addRenderer(new DefaultRenderer());
+
+            var logo = content.Load<Microsoft.Xna.Framework.Graphics.Texture2D>("nez-logo-black");
+            createEntity("logo")
+                .setPosition(Screen.center)
+                .addComponent(new Nez.Sprites.Sprite(logo));
+        }
+    }
+}