Change order of menu items

First of all, thank you thank you thank you, I looooove this theme!

I’ve been playing around and I’d like to know how to change the order of the menu items. I’ve created a child theme, and changed the float from “right” to “none” for .main-navigation, however, the menu items are still appearing in the reverse order: http://adventuresinbiscuits.com/

Not sure if makes a difference but I centered the text using the following css (thanks Andrew Nevins):
#masthead img,
.main-navigation,
#main {
display: table;
margin: 0 auto;
float: none;
width: auto;
}

#colophon {
text-align: center;
}

Any help would be appreciated 🙂