I'm using the Celestial - Lite theme & I am unable to show your icons horizontally in the footer, they will only show vertically.
I did try the following, but to no joy.
To fix it, I went into Appearance -> Montezuma Options -> CSS Files and the default CSS file that's opened is content.css
Go to the very bottom of that CSS file and add the following block:
I look forward to your help.