diff --git a/_memo/singleton-design-pattern.md b/_memo/singleton-design-pattern.md
index 31102fd0..ed88b89a 100644
--- a/_memo/singleton-design-pattern.md
+++ b/_memo/singleton-design-pattern.md
@@ -2,8 +2,8 @@
 tags: 
   - design-pattern
   - creational
-	- golang
-	- software-architecture
+  - golang
+  - software-architecture
 title: "A tour of Singleton design pattern with Golang"
 description: "Singleton real-world problem, concept, solution, use cases, implementations, pros & cons, references"
 authors: