diff --git a/src/themes/csharpDark.ts b/src/themes/csharpDark.ts
new file mode 100644
index 0000000..a811729
--- /dev/null
+++ b/src/themes/csharpDark.ts
@@ -0,0 +1,54 @@
+import { ITheme } from "./ITheme";
+
+export const CSharpDark: ITheme = {
+  /** Display name */
+  DisplayName: 'CSharpDark',
+  /** Code styles */
+  CodeStyles: {
+    Keyword: {
+      Color: '569cd6'
+    },
+    Comment: {
+      Color: '56a64a'
+    },
+    Plaintext: {
+      Color: 'dedede'
+    },
+    Punctuation: {
+      Color: 'dedede'
+    },
+    String: {
+      Color: 'dadada'
+    },
+    Literal: {
+      Color: 'dadada'
+    },
+    Type: {
+      Color: '4ec9b0'
+    },
+    Tag: {
+      Color: 'd7bb7d'
+    },
+    AttributeName: {
+      Color: '4ec9b0'
+    },
+    AttributeValue: {
+      Color: '569cd6'
+    },
+    Decimal: {
+      Color: 'b5cea8'
+    },
+    NoCode: {
+      Color: '000',
+      BackgroundColor: 'none'
+    }
+  },
+  // Background color
+  BackgroundStyle: {
+    BackgroundColor: '1e1e1e'
+  },
+  // Line number background colors
+  LineNumberStyle: {
+    Color: 'e0e0e0'
+  }
+}
\ No newline at end of file
diff --git a/src/themes/index.ts b/src/themes/index.ts
index 85e2e1c..eab7a72 100644
--- a/src/themes/index.ts
+++ b/src/themes/index.ts
@@ -8,6 +8,7 @@ import { A11YLight } from './A11YLight';
 import { AtelierCaveLight } from './AtelierCaveLight';
 import { AtelierCaveDark } from './AtelierCaveDark';
 import { BlueHintGray } from './BlueHintGray';
+import { CSharpDark } from './CSharpDark';
 import { ChatGPTDark } from './ChatGPTDark';
 import { ThonnyDefaultLight } from './ThonnyDefaultLight';
 
@@ -44,8 +45,9 @@ export const Themes: ThemeDictionary = {
   AtelierCaveLight,
   AtelierCaveDark,
   BlueHintGray,
+  CSharpDark,
   ChatGPTDark,
-  ThonnyDefaultLight,
+  ThonnyDefaultLight
 }
 
 export function GetLineNumberStyle(theme: string) {