以下に HTML コードを示します。
<div id="footer-widgets" class="grid-container clearfix">
<div class="footer-box grid-3">
<div class="footer-widget wpex-social-widget clearfix"><h4>UNITE WITH US :</h4><ul class="wpex-clearfix"><li class="wpex-social-twitter"><a href="https://twitter.com/mockinvest" title="twitter"><img src="http://www.invadewallst.com/wp-content/themes/invadewallst/images/social/twitter.png" alt="Twitter"></a></li><li class="wpex-social-facebook"><a href="http://www.facebook.com/pages/iMock-Invest/368514516550764?ref=hl" title="facebook"><img src="http://www.invadewallst.com/wp-content/themes/invadewallst/images/social/facebook.png" alt="Facebook"></a></li><li class="wpex-social-youtube"><a href="http://www.youtube.com/imockinvest" title="youtube"><img src="http://www.invadewallst.com/wp-content/themes/invadewallst/images/social/youtube.png" alt="YouTube"></a></li></ul></div> </div>
<!-- /footer-left -->
</div>
<!-- /footer-middle -->
<div class="footer-box grid-3">
</div>
<!-- /footer-right -->
<div class="footer-box grid-3">
</div>
<!-- /footer-right -->
</div>
<br/>
CSSの変更箇所を教えてください。