表格单元格内画虚线
?????? 今天上网查询了一种能在表格单元格内画虚线的方法：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><title>无标题文档</title></head><style type="text/css"> <!-- table.t1 { } table.t1 td{ border-bottom: 1pt dotted #ff3805; } --> </style> <body><table width="500" border="0" cellpadding="0" cellspacing="0" class="t1"> <tr> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> </tr> <tr> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> </tr> <tr> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> </tr> </table></body></html>?