อยากให้ตารางแสดงข้อมูลสลับสีกัน เช่น สีขาว กับสีเทา ต้องทำยังไง

<?
$i=0;
while($objResult = mysql_fetch_array($objQuery))
{
$i++;
if($i%2==0)
{
$bg = "#CCCCCC";
}
else
{
$bg = "#FFFFFF";
}
?>
<tr bgcolor="<?=$bg;?>">

		if($i%2==0){
			$bg = "#5a5a5a";
		}else{
			$bg = "#525252";
		}

<table width="555" border="0">
  <tr>
    <th width="43" scope="col">ID</th>
    <th width="149" scope="col">NAME - SURNAME</th>
    <th width="108" scope="col">USER</th>
    <th width="127" scope="col">PASSWORD</th>
    <th width="51" scope="colDETAIL</th>
    <th width="51" scope="col">DROP</th>
  </tr>$Result=mysql_query("SELECT * FROM register ORDER BY Id DESC LIMIT $Page_Start,$Per_Page") or die (mysql_error());
	$i=0;
	while($Register=mysql_fetch_array($Result)){ 
	$i++;
	if (($i%2)==0){?>
	
	<tr>
    <td bgcolor="#a5c63b"> <? echo $Register['Id']; ?> </td>
    <td bgcolor="#a5c63b"><? echo $Register['Name']; ?>&nbsp; <? echo $Register['Surname']; ?> </td>
    <td bgcolor="#a5c63b"> <? echo $Register['User']; ?></td>
    <td bgcolor="#a5c63b"> <? echo $Register['Password']; ?></td>
    <td bgcolor="#a5c63b"><img src="../picture/mini-edit1.jpg" width="26" height="23" border="0" /></td>
    <td bgcolor="#a5c63b"><img src="../picture/meni-del1.jpg" width="26" height="23" border="0" onclick="return confirm('ยืนยันการลบ');"/></td>
  </tr>
	<? }else{?>
	<tr>
    <td><? echo $Register['Id']; ?></td>
    <td><? echo $Register['Name']; ?>&nbsp; <? echo $Register['Surname']; ?></td>
    <td><? echo $Register['User']; ?> </td>
    <td> <? echo $Register['Password']; ?></td>
    <td><img src="../picture/mini-edit.jpg" width="26" height="23" border="0" /></td>
    <td><img src="../picture/mini-del.jpg" width="26" height="23" border="0" onclick="return confirm('ยืนยันการลบ');"/></td>
  </tr>
	
	
	<? }} ?>  
</table>