I keep getting an error message saying my header is 32px not 16. No matter how I type it, it will not change in the preview box
You need to remember what comes at the end of every style in css. Remember, it is basically the css version of a period. Look at your code and think very carefully about what you are missing. Everybody forgets it very once in a while, and it plays a very small but important rule in styling your webpage.