【css-技巧】细线表格

<style type="text/css">.pre_table tr th {background-color:#c9c9c9;border-bottom:thin solid gray;border-right:thin solid gray;border-left:thin solid gray;}.pre_table tr td {border-bottom:thin solid gray;border-right:thin solid gray;}.preFirstLine {border-top:thin solid gray;}</style><table  class='pre_table' width='100%' cellspacing='1'>                        <tr >                <th width='25%' scope='row' class='preFirstLine'>xx</th>                <td colspan='5' id='pre_slug' class='preFirstLine'></td>            </tr>            <tr>                <th colspan='1' scope='row'>yy</th>                <td colspan='5' id='pre_proUnit'></td>            </tr></table>