<script src="http://libs.baidu.com/jquery/1.11.3/jquery.min.js" type="text/javascript"></script>

<script type="text/javascript">

var num = 2,//点亮星星

$rating = $('#rating');

$item = $rating.find('.rating-item');

var lightOn = function(num){

$item.each(function(index){

if(index<num){

$(this).css('background-position','0 0');

}else{

$(this).css('background-position','0 -525px');

}

});

}

//初始化

lightOn(num);

//事件绑定

$item.on('mouseover',function(){

lightOn($(this).index()+1);

}).on('click',function(){

num = $(this).index + 1;

});

$rating.on('mouseout',function(){

lightOn(num);

});

</script>