diff --git a/3. Code style.md b/3.-Code-style.md
similarity index 98%
rename from 3. Code style.md
rename to 3.-Code-style.md
index 7bc794b..cdec87b 100644
--- a/3. Code style.md	
+++ b/3.-Code-style.md
@@ -1,6 +1,6 @@
 ## Indentation
 Never use tabs!
-Use 2 spaces to indent.
+Use 4 spaces to indent.
 
 ## Quotes
 Always use double-quotes!