footer bottom for all page

html{
margin: 0;
    padding: 0;
    height: 100%;
}

.footer{

position: fixed;

    bottom: 0;

}

reference site:
http://stackoverflow.com/questions/3443606/make-footer-stick-to-bottom-of-page-correctly
http://support.cargocollective.com/customer/portal/articles/725302-add-a-site-footer