h5軟鍵盤彈出頂起頁面佈局問題解決

窗口改變時設置定位屬性，窗口再次改變回來的時候要把定位屬性去掉

<script>
    var oHeight = $(document).height();
    $(window).resize(function(){
        if($(document).height() < oHeight){
            $('#footer').css("position","static");
        }else{
            $('#footer').css("position","");
        }
    })
</script>