Message Area Width

[Kiint]

I'm having a few problems creating a customised "Message Area Width" for a page I'm creating.

I've tried the following method but the width of the form is restricted by the style i'm using, yet I don't want to change the style as this will mess up the rest of the site, I only want it on this particular form

PHP Code:

  // bring up empty VBform to insert text
  $article["message"] = 'Enter your first step here';
  $stylevar['messagewidth'] = 580;
  $show['wysiwyg'] = ($setting['allow_bbcode'] ? is_wysiwyg_compatible() : 0);
  $istyles_js = construct_editor_styles_js();
  $show['qr_require_click'] = 0;
  $editorid = construct_edit_toolbar($article["message"], 0, '', ($setting['allow_smilies'] ? 1 : 0), 1, false, 'fe');
  $messagearea = "
      <script type=\"text/javascript\">
      <!--
       var require_click = false;
       var threaded_mode = 1;
       var is_last_page = false;
      // -->
      </script>
      $messagearea
  "; 


I'd like to have the form resize to the width of the table it's in, but no matter what I change $stylevar['messagewidth'] to, the style over-rides it. If I remove that line the style will set the width

so is it possible to use the code above to make the message area resize to the size of the table that I want to display it in?

Please help