diff --git a/fido2/ctap.c b/fido2/ctap.c
index c77387e..240b00a 100644
--- a/fido2/ctap.c
+++ b/fido2/ctap.c
@@ -597,18 +597,21 @@ static uint32_t ctap_assertion_led_colour(uint8_t * seed, uint32_t slen)
 	crypto_sha256_hmac_final(seed, slen, hmac);
 	uint32_t colour = 0;
 	uint32_t backlist[] = {0x00FF00};
-	uint32_t dist = 0;
-	uint32_t min_dist = 40*40*3;
+	int dist = 0;
+	int min_dist = 50*50*3;
 	for(int i=0; i<32-3 && (dist < min_dist || i == 0);i++) {
 		uint8_t* rgb = &hmac[i];
 		colour = ((uint32_t*) rgb)[0] & 0x0000ffffff;
-		uint32_t r, g, b = 0;
+		int r, g, b = 0;
 		r = colour & 0x0000ff0000 >> 16;
 		g = colour & 0x000000ff00 >> 8;
 		b = colour & 0x00000000ff;
 		for(int j=0; j < 1 && dist < min_dist; j++) {
-			uint8_t* b_rgb = &((uint8_t*) &backlist[j])[1];
-			dist = ((int) r - b_rgb[2])*(r  - b_rgb[2]) + ((int)g - b_rgb[1])*((int)g - b_rgb[1]) + ((int)b - b_rgb[0])*((int)b - b_rgb[0]);
+			int br, bg, bb = 0;
+			br = backlist[j] & 0x0000ff0000 >> 16;
+			bg = backlist[j] & 0x000000ff00 >> 8;
+			bb = backlist[j] & 0x00000000ff;
+			dist = ((int) r - br)*(r  - br) + ((int)g - bg)*((int)g - bg) + ((int)b - bb)*((int)b - bb);
 		}
 
 	}