diff --git a/src/epub_converter/css_preprocessing.py b/src/epub_converter/css_preprocessing.py
index ff4a347..fa72c12 100644
--- a/src/epub_converter/css_preprocessing.py
+++ b/src/epub_converter/css_preprocessing.py
@@ -5,7 +5,7 @@ from ebooklib import epub
 from bs4 import BeautifulSoup
 from itertools import takewhile
 
-from src.util.color_reader import str2hex
+from src.util.color_reader import str2hex, rgb2color_name
 from src.livecarta_config import LiveCartaConfig
 
 
@@ -129,8 +129,7 @@ LIVECARTA_STYLE_ATTRS_MAPPING = {
     'font-variant': lambda x: x,
     'text-align': lambda x: x,
     'font': lambda x: '',
-    'font-family': lambda x: LiveCartaConfig.FONT_CORRESPONDANCE_TABLE.get(x) or
-    LiveCartaConfig.FONT_CORRESPONDANCE_TABLE.get(x.capitalize()),
+    'font-family': lambda x: LiveCartaConfig.FONT_CORRESPONDANCE_TABLE.get(re.sub(r"^\s+|\s+$", "", x.title())),
     'font-size': convert_tag_style_values,
     'color': get_text_color,
     'background-color': get_bg_color,
@@ -179,7 +178,7 @@ def build_inline_style_content(style: str) -> str:
     """Build inline style with livecarta convention"""
     # replace all spaces between '; & letter' to ';'
     style = re.sub(r"; *", ";", style)
-    # when we split style by ';', last element of the list is ''-None
+    # when we split style by ';', last element of the list is '' - None
     # remove it
     split_style: list = list(filter(None, style.split(';')))
     # replace all spaces between ': & letter' to ':'
@@ -198,7 +197,7 @@ def update_css_styles_to_livecarta_convention(css_rule: cssutils.css.CSSStyleRul
         css_rule.style[style_type.name] = ''
         return
 
-    cleaned_value = style_type.value.replace('\"', '').split(', ')[-1]
+    cleaned_value = style_type.value.replace('\"', '')
     constraints_on_value = LIVECARTA_STYLE_ATTRS.get(
         style_type.name)
     value_not_in_possible_values_list = cleaned_value not in LIVECARTA_STYLE_ATTRS[
@@ -215,7 +214,7 @@ def update_css_styles_to_livecarta_convention(css_rule: cssutils.css.CSSStyleRul
 
 def build_css_file_content(css_content: str) -> str:
     """Build css content with livecarta convention"""
-    sheet = cssutils.parseString(css_content, validate=False)
+    sheet = cssutils.parseString(css_content.lower(), validate=False)
 
     for css_rule in sheet:
         if css_rule.type == css_rule.STYLE_RULE:
diff --git a/src/util/color_reader.py b/src/util/color_reader.py
index 706da61..fe44758 100644
--- a/src/util/color_reader.py
+++ b/src/util/color_reader.py
@@ -103,13 +103,12 @@ def str2hex(s: str):
             return rgb_percent_to_hex((r, g, b))
 
     if 'rgb' in s:
-        match = re.search(r'rgba*\(((\d+), *(\d+), *(\d+), (\d\.\d+)*)\)', s)
-        if match:
-            r, g, b = int(match.group(2)), int(match.group(3)), int(match.group(4))
-            if match.group(5):
-                alpha = float(match.group(5))
-                r, g, b = rgba2rgb(r, g, b, alpha)
-            return rgb_to_hex((r, g, b))
+        rgba = re.findall('([0-9] *\.?[0-9]+)', s)
+        r, g, b = int(rgba[0]), int(rgba[1]), int(rgba[2])
+        if len(rgba) == 4:
+            alpha = float(rgba[3])
+            r, g, b = rgba2rgb(r, g, b, alpha)
+        return rgb_to_hex((r, g, b))
 
     if 'hsl' in s:
         # hsl(hue in {0,360}, saturation [0, 100%], lightness [0, 100%])