Update README.md

Author: panicdragon

README.md

@@ -4,5 +4,12 @@ Blazor WebAssembly on Unity WebGL（WebAssembly）
 
 include contents [CubeWorld](https://github.com/federicodangelo/CubeWorld)
 
+<img width="875" alt="unityweb" src="https://user-images.githubusercontent.com/1584153/215248965-350b415b-2824-4652-b9ea-d7da89838be8.png">
 
+## spec
+
+- Unity 2019.3.13
+- Visual Studio Community 2019 for Mac Version 8.10.25 (build 2)
+- .NET Core 3.1 SDK
+- .NET 5.0 SDK