How I chenged checkbox bg color on when it is checked?

Your are not setting the color on the label but on the checkbox. jQuery makes it easy for you to select / traverse DOM elements (and also helps clean-up a lot of unnecessary IDs), see this fiddle :

$('input[type=checkbox]').change(function(){
    if($(this).prop('checked')){   
        $(this).parent().css('backgroundColor', '#bff0a1');
    }else{
        $(this).parent().css('backgroundColor', '#eee');        
    }
});

Live Example