Set correct regex for rgba

src/util/color_reader.py

@@ -103,7 +103,7 @@ def str2hex(s: str) -> str:
             return rgb_percent_to_hex((r, g, b))
 
     if "rgb" in s.lower():
-        rgba = re.findall("([0-9] *\.?[0-9]+)", s)
+        rgba = re.findall("(\d+(?:\.\d+)?)", s)
         r, g, b = int(rgba[0]), int(rgba[1]), int(rgba[2])
         if len(rgba) == 4:
             alpha = float(rgba[3])