For a lot of folks out there, HTML on its own is boring, after all, nothing is exciting when there is no color in it. Now add some Cascading Style Sheets (CSS) either to your web page or an email, and things are colorful, engaging, and begin to stand out. 

But dealing with HTML email building that has CSS in it can be tricky due to the way email clients “read the code”. In this article, we will go over the main principles of using CSS in emails and take a look at some examples that demonstrate how to do so.