Ever wanted to add alternating background colors (a.k.a. "zebra stripes") to your webform fields? I had a need to do this a couple of days ago and struggled to find a method for this. Little did I know that the webform module actually has a few template files included with it that you can use to override what's going on in the theme layer.
The particular thing I wanted to do was to add some CSS to the webform fields so that I could do some easy CSS zebra striping. I know this is super easy to do with the output of the Views module because of the "row-even" and "row-odd" CSS classes that are provided out of the box. I wanted to be able to do some similar CSS classes on my webform fields. Getting the job done requires taking the "webform-form.tpl.php" default template file in the Webform module directory and copying it to own your custom theme directory.
Here's the code I ended up using: