diff --git a/_layouts/default.html b/_layouts/default.html
index 80c4541..d525d4c 100644
--- a/_layouts/default.html
+++ b/_layouts/default.html
@@ -17,7 +17,7 @@
     <style>
         .language-shell.highlighter-rouge {
             /* New styles for Shell code */
-            background-color: #f0f0f0; /* Example background color */
+            background-color: #ffffcc; /* Example background color */
             color: #333; /* Example text color */
             padding: 10px; /* Example padding */
             border: 1px solid #ccc; /* Example border */
@@ -26,7 +26,7 @@
         }
         .language-python {
             /* New styles for Python code */
-            background-color: #f7f7f7; /* Light grey background */
+            background-color: #ffffcc; /* Light grey background */
             color: #202020; /* Dark grey text color */
             padding: 10px; /* Padding around the code block */
             border: 1px solid #ccc; /* Example border */
@@ -35,7 +35,7 @@
         }
         .language-matlab {
             /* New styles for MATLAB code */
-            background-color: #FFFFCC; /* Light yellow background */
+            background-color: #ffffcc; /* Light yellow background */
             color: #0052cc; /* MATLAB blue text color */
             padding: 10px; /* Padding around the code block */
             border: 1px solid #ccc; /* Example border */