diff --git a/examples/button.c b/examples/button.c
index be4a0a0..a163ec7 100644
--- a/examples/button.c
+++ b/examples/button.c
@@ -1,30 +1,23 @@
 #include <stdlib.h>
 #include <ptk.h>
+#include <ptk_color.h>
 #include <ptk_log.h>
 
-#include <GLFW/glfw3.h>
-
-static const float color_step = 10.0f;
+static const float step = 5.0f;
+static float hue = 360.0f;
 
 static PtkRect *r;
 
 static void on_press(const int button, const int mods) {
     (void)button; (void)mods;
     PTK_DEBUG("pressed!");
-    r->color.b += color_step / 255.0f;
-    if (r->color.b > 1.0f) {
-        r->color.b = 0.0f;
 
-        r->color.g += color_step / 255.0f;
-        if (r->color.g > 1.0f) {
-            r->color.g = 0.0f;
-
-            r->color.r += color_step / 255.0f;
-            if (r->color.r > 1.0f) {
-                r->color.r = 0.0f;
-            }
-        }
+    hue += step;
+    if (hue > 360.0f) {
+        hue = 0.0f;
     }
+
+    r->color = ptk_hsv_to_rgb((PtkHSV){ .h = hue, .s = 360.0f, .v = 360.0f });
 }
 
 int main(void) {
@@ -35,7 +28,7 @@ int main(void) {
     r = (PtkRect *)ptk_rect(
         (PtkPos){ .x = 100.0f, .y = 100.0f },
         (PtkSize){ .w = 100.0f, .h = 50.0f },
-        (PtkRGB){ .r = 1.0f, .g = 1.0f, .b = 1.0f }
+        (PtkRGB){ .r = 1.0f, .g = 0.0f, .b = 0.0f }
     );
 
     return ptk_run(