Thanks. This got me started in the right direction. Just in case anyone else needs it below is all the CSS I ended up with. It allowed me to center the icons, made the margin smaller for mobile only and added a little hover effect.

.avia_codeblock .av_font_icon {
margin-right: 30px;
}

.avia_codeblock .av_font_icon:hover {
opacity: .8;
filter:alpha(opacity=80); /* For IE8 and earlier */
}

.avia_codeblock .av_font_icon {
display: inline-block;
float: none;
}

@media only screen and (max-width: 767px){
.avia_codeblock .av_font_icon {
margin-right: 20px;
}
}