高度为100%的table，如何固定第一行的高度？？？
<!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><title></title></head> <body style="height:100%; padding:0px; margin:0px;"> <table style="width:100%; height:100%;"> <tr style="height:30px; background-color:Blue;"> <td></td> </tr> <tr style="height:auto; background-color:Red;"> <td></td> </tr> </table> </body></html>
<!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><title>No Title</title><style type="text/css">html, body { margin:0px; height:100%; padding:0px;}#theTable { width:100%; height:100%; background-color:#fff;text-align:center;border-collapse:collapse;}#theTable td{border:1px solid black;}#theTable tr.firstTr {background-color:blue;width:100%;height:30px;_position:absolute; }#theTable tr.firstTr td{border:1px solid black;}#theTable tr.firstTr td div{height:30px;overflow:hidden;}#theTable tr.secondTr {background-color:#ccc;width:100%;height:auto;vertical-align:top;}#theTable tr.secondTr td{_padding-top:32px;}</style></head> <body> <table id="theTable" border="0"> <tr class="firstTr"> <td><div>a1<br />222<br />333</div></td><td>a2</td> </tr> <tr class="secondTr"> <td>b1</td><td>b2</td> </tr> </table> </body></html>