I am following [this SharePoint 2010 tutorial][1] where the author is adding styles directly in the html mark-up of the page.

When I edit the mark-up in SharePoint 2013 and click OK initially the styles are applied, but when I click save and view the page again, all styles have been stripped out.

How do I apply styles to html elements within SharePoint 2013?

  [1]: http://www.codeproject.com/Tips/493775/Apply-CSS-styles-to-SharePoint-Web-parts