I've been writing my first HTML CSS website and I'm confused by what is messing up my navbar on Firefox because for some reason it's showing up above the page window. Is there a -moz- prefix that I am missing? Here's the website: http://fightthefamine.org/
Replace .homepage .navbar with the following in your CSS.
.homepage .navbar {
display: inline-table;
position: relative;
top: -30px;
}