About Form Request more Details

I'm customizing theme_black, and i would like to know how i can expand the select name or input text... i tried to add "width='xxx'" but doesn't work.
There isn't margin-left and i would like to make it better.

Is possible?

Thanks a lot

PD: Here you are a caption

Hi,
We can't set the width of the "Request more details form", the width size of it is defined by class name "span4"
Find this
<div class="span4">
<!-- request -->
<?php
// if (version_compare(JVERSION, '3.0', 'lt')) {
//echo JHtml::_('sliders.start', 'slide-details1');
//echo JHtml::_('sliders.panel', JText::_('OS_REQUEST_MORE_INFOR'), 'slide1');
?>
<div class="accordion">
<div class="accordion-group">
<div class="accordion-heading">
<strong>
<span class="accordion-toggle"><?php echo JText::_('OS_REQUEST_MORE_INFOR')?></span>
</strong>
</div>
<div class="accordion-body collapse in">
<div class="accordion-inner">

and change to

<div class="span4" style="margin-left:10px;">
<!-- request -->
<?php
// if (version_compare(JVERSION, '3.0', 'lt')) {
//echo JHtml::_('sliders.start', 'slide-details1');
//echo JHtml::_('sliders.panel', JText::_('OS_REQUEST_MORE_INFOR'), 'slide1');
?>
<div class="accordion">
<div class="accordion-group">
<div class="accordion-heading">
<strong>
<span class="accordion-toggle"><?php echo JText::_('OS_REQUEST_MORE_INFOR')?></span>
</strong>
</div>
<div class="accordion-body collapse in">
<div class="accordion-inner">

It will create the margin left for that form
Thanks
Dam