How to code this css so the #footerSocial is centered ?

#footerSocial {
float: left;
width: 220px;
padding: 60px 0 0 0;
margin: 0 0 0 100px; }

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I tried several ways yet no luck

#footerSocial {
margin-left:auto;
margin-right:auto;
width: 220px;
padding: 60px 0 0 0;
margin: 0 0 0 100px; }

All help greatly appreciated