代码：

CSS代码：
.button {
    height: 34px;
    padding: 0 1em 2px;
    border: 0;
    background: url(images/gray_baidu_btn.png) 100% -36px no-repeat;
    background: url(images/gray_baidu_btn.png) no-repeat, url(images/gray_baidu_btn.png) 100% -36px no-repeat;
    filter: progid:DXImageTransform.Microsoft.AlphaImageLoader (src='images/gray_baidu_btn.png', sizingMethod='crop');
    font-size: 14px;
    overflow: visible;
    cursor: pointer;
}
HTML代码：
<input type="button" class="button" value="我4个字" /><br />
<input type="button" class="button" value="我靠，我N多字" /><br />
<input type="button" class="button" value="上面两位请淡定" /><br />
<input type="button" class="button" value="一群笨蛋" />

效果：