for evaluating nth-child(2) make step and offset visible

Author: inforithmics

src/ExCSS/Selectors/ChildSelector.cs

@@ -5,8 +5,8 @@ namespace ExCSS
     public abstract class ChildSelector : StylesheetNode, ISelector
     {
         private readonly string _name;
-        protected int Step;
-        protected int Offset;
+        public int Step { get; private set; }
+        public int Offset { get; private set; }
         protected ISelector Kind;
 
         protected ChildSelector(string name)