Javascript和jQuery获取对象的方法

<div id="a">我是实验品</div>
<script type="text/javascript">
 var ss = document.getElementById("a");//获取ID值为a的标签并保存到ss里
 ss.style.color="red";//修改属性字体颜色为红色
</script>

<script src="jquery-2.1.4/jquery.min.js"></script> //导入jQuery所需js包
<script type="text/javascript">
 function tj(){
 $('input[name="c"]').css("background-color","yellow");
 }
 function tj1(){
 $("#a").css("background-color","red");
 }
</script>
<input onmouseover="tj()" onmouseout="tj1()" id="a" class="b" name="c" type="submit" value="指着我" >