sominparate on "Can't center align footer content"

Replace your css with my css.this will help you.

#footerColumn {
margin: 0 0 10px 10px;
}

Next:

Remove width

#footer ul {
display: block;
margin-bottom: 10px;
margin-left: auto;
margin-right: auto;
text-align: center;
}

Remove float:left

#footer ul li{
clear: right;
display: inline;
font-size: 11px;
font-weight: bold;
line-height: 18px;
margin-right: 15px;
text-align: center;
}

This will might help you.

Thanking you.
Somin