diff --git a/fibeamer/fibeamer.dtx b/fibeamer/fibeamer.dtx
index 45721c796d3d1989396e89b4af6af8817f11319e..6b2a99d8bf4938ebcca622bee31a4aec5001cb51 100644
--- a/fibeamer/fibeamer.dtx
+++ b/fibeamer/fibeamer.dtx
@@ -287,7 +287,7 @@
 %    \end{macrocode}
 % When the |fonts| option is specified, the following packages will
 % be used by the package to configure the fonts in the presentation
-% mode.
+% mode:
 % \begin{itemize}
 %   \item\textsf{ifthen} -- This package is used to construct
 %     compound conditionals.
diff --git a/fibeamer/theme/mu/fi.dtx b/fibeamer/theme/mu/fi.dtx
index e22c95aa66d74148f64b2a65fb2d8cbea811af2e..035c6405d581ebdc93e5c28510c01561649c9b39 100644
--- a/fibeamer/theme/mu/fi.dtx
+++ b/fibeamer/theme/mu/fi.dtx
@@ -16,7 +16,7 @@
 % dark frames.
 %    \begin{macrocode}
   \definecolor{fibeamer@gold}{HTML}{a47312}
-  \definecolor{fibeamer@yellow}{HTML}{FFE169}
+  \definecolor{fibeamer@yellow}{HTML}{FFEB9C}
   \definecolor{fibeamer@yellowDark}{HTML}{E9BC09}
   \definecolor{fibeamer@gray}{HTML}{999999}
   \colorlet{fibeamer@backgroundInner}{fibeamer@gold}
diff --git a/fibeamer/theme/mu/fsps.dtx b/fibeamer/theme/mu/fsps.dtx
index a6ecc82d24fb63e5e82e10f6b4d2bc0eac5e6959..e85a32a94cd0df98d12b34d88c541717329d5e5d 100644
--- a/fibeamer/theme/mu/fsps.dtx
+++ b/fibeamer/theme/mu/fsps.dtx
@@ -41,7 +41,7 @@
       \setbeamercolor*{block title example}{
         use=example text, fg=white, bg=fibeamer@blue!60!white}
       \setbeamercolor*{block title alerted}{
-        use=alerted text, fg=white, bg=fibeamer@blue!90!white}
+        use=alerted text, fg=white, bg=fibeamer@blue!95!white}
       \setbeamercolor*{block body}{
         fg=fibeamer@blue, use=block title,
         bg=fibeamer@gray!15!white}
diff --git a/fibeamer/theme/mu/fss.dtx b/fibeamer/theme/mu/fss.dtx
index 602b9f98f720c7ad2788234574f5667a10167bc9..c19ab68f03dd6e49187b74446a94f9bfec87df48 100644
--- a/fibeamer/theme/mu/fss.dtx
+++ b/fibeamer/theme/mu/fss.dtx
@@ -17,7 +17,7 @@
 %    \begin{macrocode}
   \definecolor{fibeamer@cyan}{HTML}{00796E}
   \definecolor{fibeamer@gray}{HTML}{999999}
-  \colorlet{fibeamer@backgroundInner}{fibeamer@cyan}
+  \colorlet{fibeamer@backgroundInner}{fibeamer@cyan!80!black}
   \colorlet{fibeamer@backgroundOuter}{fibeamer@cyan!60!black}
 %    \end{macrocode}
 % The |darkframes| environment switches the |\iffibeamer@darktrue|
@@ -41,7 +41,7 @@
       \setbeamercolor*{block title example}{
         use=example text, fg=white, bg=fibeamer@cyan!60!white}
       \setbeamercolor*{block title alerted}{
-        use=alerted text, fg=white, bg=fibeamer@cyan!90!white}
+        use=alerted text, fg=white, bg=fibeamer@cyan}
       \setbeamercolor*{block body}{
         fg=fibeamer@cyan, use=block title,
         bg=fibeamer@gray!15!white}
diff --git a/fibeamer/theme/mu/phil.dtx b/fibeamer/theme/mu/phil.dtx
index dff63779ca1ac73be607e2c98f7f9c44543b7205..e8c199891a429f563adf909a860efeca917bdd70 100644
--- a/fibeamer/theme/mu/phil.dtx
+++ b/fibeamer/theme/mu/phil.dtx
@@ -17,7 +17,7 @@
 %    \begin{macrocode}
   \definecolor{fibeamer@blue}{HTML}{0071B2}
   \definecolor{fibeamer@gray}{HTML}{999999}
-  \colorlet{fibeamer@backgroundInner}{fibeamer@blue}
+  \colorlet{fibeamer@backgroundInner}{fibeamer@blue!80!black}
   \colorlet{fibeamer@backgroundOuter}{fibeamer@blue!60!black}
 %    \end{macrocode}
 % The |darkframes| environment switches the |\iffibeamer@darktrue|
@@ -41,7 +41,7 @@
       \setbeamercolor*{block title example}{
         use=example text, fg=white, bg=fibeamer@blue!60!white}
       \setbeamercolor*{block title alerted}{
-        use=alerted text, fg=white, bg=fibeamer@blue!90!white}
+        use=alerted text, fg=white, bg=fibeamer@blue}
       \setbeamercolor*{block body}{
         fg=fibeamer@blue, use=block title,
         bg=fibeamer@gray!15!white}
diff --git a/fibeamer/theme/mu/sci.dtx b/fibeamer/theme/mu/sci.dtx
index 9e9cfb3ea39be639963bcedeac237d765d0f8214..f08e0c86c05f7e20c4cdc96950b73599d9c78cf2 100644
--- a/fibeamer/theme/mu/sci.dtx
+++ b/fibeamer/theme/mu/sci.dtx
@@ -17,7 +17,7 @@
 %    \begin{macrocode}
   \definecolor{fibeamer@green}{HTML}{139632}
   \definecolor{fibeamer@gray}{HTML}{999999}
-  \colorlet{fibeamer@backgroundInner}{fibeamer@green}
+  \colorlet{fibeamer@backgroundInner}{fibeamer@green!90!black}
   \colorlet{fibeamer@backgroundOuter}{fibeamer@green!60!black}
 %    \end{macrocode}
 % The |darkframes| environment switches the |\iffibeamer@darktrue|
@@ -41,7 +41,7 @@
       \setbeamercolor*{block title example}{
         use=example text, fg=white, bg=fibeamer@green!60!white}
       \setbeamercolor*{block title alerted}{
-        use=alerted text, fg=white, bg=fibeamer@green!90!white}
+        use=alerted text, fg=white, bg=fibeamer@green}
       \setbeamercolor*{block body}{
         fg=fibeamer@green, use=block title,
         bg=fibeamer@gray!15!white}