You could read:

http://www.zen-cart.com/forum/showthread.php?t=130226

We did it by editing includes / templates / yourtemplate / templates / tpl_modules_attributes.php first. This edit was just to put invidual IDs for the attributes.

Then, we used the css file to style these elements to wherever we wanted.

Be aware that if you have different attributes on different product pages then you want to be careful because these IDs are numbered from the first on the page incrementally. With hindsight, it would have been better to add the ID including the attribute name. This is pretty easily done but just didn't occur to me at the time


The line you would want to change (in our edited version of the file) is the one that reads:

Code:
<div class="wrapperAttribsOptions" id="attributeBox-<?php echo $i ?>">
You might change it too:

Code:
<div class="wrapperAttribsOptions" id="attributeBox-<?php echo $options_name[$i] ?>">
That should be fine if your attributes names do not have spaces or funky characters in them. If they do then you would need to write a bit of php to strip these out.