background for checkbox at IE

I have a list of check-boxes and in IE the last one has stra开发者_开发问答nge color. In FF it's perfect.

http://img693.imageshack.us/img693/3987/40401854.jpg

<p>
    <span>abc:</span>
    <br /><br />
    <label><input type="checkbox" id="a" name="a" <?php echo $a; ?> /> 1</label>
    <br />
    <label><input type="checkbox" id="b" name="b" <?php echo $b; ?> /> 2</label>
    <br />
    <label><input type="checkbox" id="c" name="c" <?php echo $c; ?> /> 3</label>
    <br />
    <label><input type="checkbox" id="d" name="d" <?php echo $d; ?> /> 4</label>
    <br />
    <label><input type="checkbox" id="e" name="e" <?php echo $e; ?> /> 5</label>
</p>

thank you

In Internet Explorer 8, you can press F12 to open a DOM viewer. Using this tool, you should browse to the checkbox that is giving you trouble and see how its CSS styles are different from the other checkboxes.

This could be caused by the PHP code that is being inserted. $1, $2, $3, $4 and $5 aren't valid PHP variables (see http://www.php.net/manual/en/language.variables.basics.php), try to rename them to $v1, $v2 ... $v5.

Some CSS things to check: do you have any CSS for id="e"? Or is there a :last-child CSS declaration somewhere? Try overflow:auto on the parent p element (its background color might be showing)?