diff --git a/src/custom/StyledChapter/StyledChapter.tsx b/src/custom/StyledChapter/StyledChapter.tsx
index c7f8000b..56d94814 100644
--- a/src/custom/StyledChapter/StyledChapter.tsx
+++ b/src/custom/StyledChapter/StyledChapter.tsx
@@ -14,10 +14,20 @@ const StyledChapter = styled('div')(({ theme }) => ({
     color: 'gray'
   },
 
-  a: {
-    '&:hover': {
-      color: KEPPEL
-    }
+  '& a': {
+    color: KEPPEL
+  },
+  '& pre': {
+    backgroundColor: '#011627',
+    padding: '1em',
+    borderRadius: '0.5rem',
+    overflowX: 'auto',
+    color: '#d6deeb',
+    position: 'relative',
+    textAlign: 'left',
+    width: '100%',
+    margin: '1rem auto autocompleteClasses',
+    fontFamily: 'Courier New, Courier, monospace'
   }
 }));
 export default StyledChapter;
diff --git a/src/custom/TOCChapter/TOCChapter.tsx b/src/custom/TOCChapter/TOCChapter.tsx
index 58bb4d60..35e78e96 100644
--- a/src/custom/TOCChapter/TOCChapter.tsx
+++ b/src/custom/TOCChapter/TOCChapter.tsx
@@ -1,12 +1,8 @@
 import React from 'react';
 import { TOCWrapper } from './style';
 
-interface TOCDataItem {
-  chapter: string;
-}
-
 interface TOCProps {
-  availableChapters: TOCDataItem[];
+  availableChapters: string[];
   currentChapter: string | undefined | null;
   onClick: (item: string, e: React.MouseEvent<HTMLLIElement, MouseEvent>) => void;
 }
@@ -24,13 +20,13 @@ const TOC: React.FC<TOCProps> = ({ availableChapters, currentChapter, onClick })
         <ul className={`toc-ul toc-ul-open`}>
           {availableChapters.map((item) => (
             <li
-              key={item.chapter}
-              className={item.chapter === currentChapter ? 'active-link' : ''}
+              key={item}
+              className={item + '.mdx' === currentChapter ? 'active-link' : ''}
               onClick={(e) => {
-                onClick(item.chapter, e);
+                onClick(item, e);
               }}
             >
-              <p className="toc-item"> {reformatTOC(item.chapter)}</p>
+              <p className="toc-item"> {reformatTOC(item)}</p>
             </li>
           ))}
         </ul>