diff --git a/main.cpp b/main.cpp
index 4d554d2..8e53453 100644
--- a/main.cpp
+++ b/main.cpp
@@ -35,17 +35,21 @@ static float boxSpeed = 250.f;
 const char* vShader = "#version 300 es\n"
 "layout (location = 0) in vec2 aPos;\n"
 "uniform mat4 uTransform;\n"
+"uniform vec4 uColor;\n"
+"out vec4 color;\n"
 "void main()\n"
 "{\n"
 "    gl_Position = uTransform * vec4(aPos, 0.0, 1.0);\n"
+"    color = uColor;\n"
 "}";
 
 const char* fShader = "#version 300 es\n"
 "precision mediump float;\n"
-"out vec4 FragColor;\n"
+"out vec4 fragColor;\n"
+"in vec4 color;\n"
 "void main()\n"
 "{\n"
-"    FragColor = vec4(1.0, 0.2, 0.3, 1.0); // red-ish\n"
+"    fragColor = color;\n"
 "}";
 
 void makeRotationZ(float angle, float* m)
@@ -173,6 +177,11 @@ extern "C" int APP_MAIN(int argc, char **argv) {
     glEnable(GL_DEPTH_TEST);
 
     float transform[16];
+    float color[4];
+    color[0] = 0x18 / 255.f;
+    color[1] = 0xFF / 255.f;
+    color[2] = 0x18 / 255.f;
+    color[3] = 0xFF / 255.f;
 
     while (running) {
         SDL_Event event;
@@ -202,12 +211,16 @@ extern "C" int APP_MAIN(int argc, char **argv) {
 
         float angle = SDL_GetTicks() / 1000.0f; // rotates over time
 
-        float transform[16];
         makeRotationZ(angle, transform);
 
-        GLuint loc = glGetUniformLocation(program, "uTransform");
+        GLuint tranformLoc = glGetUniformLocation(program, "uTransform");
+        GLuint colorLoc = glGetUniformLocation(program, "uColor");
+
         glUseProgram(program);
-        glUniformMatrix4fv(loc, 1, GL_FALSE, transform);
+        glUniformMatrix4fv(tranformLoc, 1, GL_FALSE, transform);
+
+        color[1] = (float)((int)angle * 10 % 255) / 255.f;
+        glUniform4fv(colorLoc, 1, color);
 
         glBindVertexArray(vao);