onmouseover和onmouseout直接写到html代码就可以。
<style>.header_1{position:absolute;top:40px;left:220px;height:auto;width:auto;color:#FFFFFF;}.d_over{background:#FF0000;}.d_out{background:#FFFFFF;}
</style><divonmouseover="this.className='d_over'"onmouseout="this.className='d_out'">333333333333333</div>