There is nothing wrong with your CSS or HTML, that I can think of, because you are using the class name and not element selector. Before you try what Solution 2 says (which is one step beyond my solution) try
CTRL and
F5, that will perform a hard refresh on the page and load everything from scratch. This will be an automatic process and your browser will reload everything and apply.
Try this code here on the JSFiddle,
Edit fiddle - JSFiddle[
^], works just fine. :-)
If this doesn't work, then a good answer can be found in the browser debug consoles. You can try using the Inspect Element option and see which styles are being applied and where they are coming from.
F12 will bring the options up, hover over the element and preview the styles being applied. Google Chrome will even show the file and the line number from where a specific style is coming from.