Intro to CSS Not Displaying Changes on Accompanying Website

For some reason when I am working through the intro to CSS course I am noticing that the website to the right that I am allegedly working on is not updating. I cannot see the changes being made to the page but apparently I am executing the exercises properly even though the program says I should be seeing changes.

Has anyone else had this issue?
Does it mean I did something improperly in an earlier exercise that should be linking the HTML and CSS and the program just blew over it?