Update README.md

Author: alesanchezr

exercises/12-Relative-Length-EM-REM/README.md

@@ -5,11 +5,13 @@ By now, we are used to working with pixels as measurement unit, for example, say
 There are other types of units that are not fixed, but relative. We use them when we want the element size to be related to another element or measurement unit.
 
 ### Example using em:
-In this exercise we have two <h2> headings. They are both <h2>, but one is bigger than the other because headings have relative font-sizes by default. Since the first div has a bigger based font-size, then the heading resizes accordingly.
+In this exercise we have two `<h2>` headings. They are both `<h2>`, but one is bigger than the other because headings have relative font-sizes by default. Since the first div has a bigger based font-size, then the heading resizes accordingly.
+
 ```Plain/Text
 em: Relative to the current font-size of the parent.
 rem: Relative to the original font-size of the page.
 ```
+
 ## 📝 Instructions:
 
 1. Give a font-size of 0.8em to both h2's