Small formatting fix to OOP tab layout

src/content/docs/products/splashkit/SplashKit Tutorials/Documentation/4-adding-oop.mdx

@@ -20,7 +20,6 @@ The full code block structure for C++, C# in top level and OOP, and Python is as
 
 ````md
 <Tabs syncKey="code-language">
-<Tabs>
 <TabItem label="C++">
 
 ```cpp
@@ -30,6 +29,7 @@ Add C++ code here
 ```
 
 </TabItem>
+<TabItem label="C#">
 <Tabs syncKey="csharp-style">
 <TabItem label="Top-level Statements">
 
@@ -50,6 +50,7 @@ Add OOP version of C# code here
 
 </TabItem>
 </Tabs>
+</TabItem>
 <TabItem label="Python">
 
 ```python