submit按钮的背景阴影如何去掉？

css 控制submit加载背景图片做提交按钮

<style type="text/css">
<!--
.button1{font-size:12px;cursor:hand;width: 58px;height: 21px;background-color: #ffffff;background-image: url(images/baby/denglu_button.jpg);background-repeat: repeat;background-attachment: scroll;background-position: center;border: 0 solid #000000;text-align: center;padding-top: 3px;}
-->
</style>

<form>

<input class="button1" type="submit" name="loginsubmit" value=" "/>

</form>