diff --git a/X10D/src/Core/RandomExtensions.cs b/X10D/src/Core/RandomExtensions.cs
index a111704..5fcb109 100644
--- a/X10D/src/Core/RandomExtensions.cs
+++ b/X10D/src/Core/RandomExtensions.cs
@@ -1,4 +1,4 @@
-using System.Globalization;
+using System.Globalization;
 using System.Text;
 using X10D.Math;
 
@@ -9,7 +9,9 @@ namespace X10D.Core;
 /// </summary>
 public static class RandomExtensions
 {
+#if !NET6_0_OR_GREATER
     private static readonly Random Shared = new();
+#endif
 
     /// <summary>
     ///     Returns a random value that defined in a specified enum.