planning#320: Moved styles semmantically correct into files

src/css/additional/reset-docusaurus-default-style.scss

@@ -4,9 +4,7 @@ button {
 }
 
 .table-of-contents a {
-  color: black;
   &:hover {
-    color: #3578e5;
     text-decoration: none;
   }
 }
\ No newline at end of file

src/css/additional/theme.scss

@@ -81,3 +81,10 @@ button:focus,
     backdrop-filter: blur(3px);
     -webkit-backdrop-filter: blur(3px);
 }
+
+.table-of-contents a {
+    color: black;
+    &:hover {
+      color: #3578e5;
+    }
+}