$(document).ready(function() {  
    footer();
});
$(window).resize(function() {
    footer();
});
function footer() {
    windowHeight = $(window).height();
    container1Height = $("#container1").height();
    footerHeight = $("#footer").height() + 40; // 40 is #mainContent top/bottom padding added together
    if (container1Height <= windowHeight) {
        $("#container1").css("padding-bottom", (footerHeight + "px"));
        $("#footer").css("position", "absolute");
        $("#footer").css("bottom", "0");
    }
    else {
    }
};