diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4e1a247..6d051df 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -6,8 +6,8 @@ add_subdirectory(converter)
 PROJECT(MarbleRaceGroupC)
 
 # ACGL setup
-SET(ACGL_OPENGL_SUPPORT CORE_40)
-ADD_DEFINITIONS(-DACGL_OPENGL_VERSION_40)
+SET(ACGL_OPENGL_SUPPORT CORE_32)
+ADD_DEFINITIONS(-DACGL_OPENGL_VERSION_32)
 ADD_DEFINITIONS(-DACGL_OPENGL_PROFILE_CORE)
 # create the newest availabe OpenGL context, independent of the ACGL version:
 #ADD_DEFINITIONS(-DGLFW_OPENGL_LATEST_VERSION)
diff --git a/Shader/phong.fsh b/Shader/phong.fsh
index f80b4d4..af8a2e8 100644
--- a/Shader/phong.fsh
+++ b/Shader/phong.fsh
@@ -1,4 +1,4 @@
-#version 400
+#version 150
 
 in vec3 vNormal;
 in vec2 vTexCoord;