fix(theming): replace elementColor dark value with better contrast #8c8c8c

Signed-off-by: John Molakvoæ <skjnldsv@protonmail.com>

Author: skjnldsv

apps/theming/lib/Util.php

@@ -91,7 +91,7 @@ public function elementColor($color, bool $brightBackground = true) {
 
 		if (!$brightBackground && $luminance < 0.2) {
 			// If the color is too dark in dark mode, we fall back to a brighter gray
-			return '#555555';
+			return '#8c8c8c';
 		}
 
 		return $color;