Section wrapper

Take a look at this screenshot: http://minus.com/lbwVFtrSuvQOYI

I added an HTML block before the Address Information, then one between the Address and Contact sections, then one after Contact Information. In the first HTML block, close the list (< /li >< /ul>) and open a div with a class or ID so you can style it, then open the list again (< ul >). Then, between the Address and Contact sections, I added another HTML field: close the list again (< /li > < /ul >) then close the div (< /div >) then open a new div for the Contact section, and open the list again.

Finally, after the last section, close the div.

I also checked the box to disable the default margins on all the HTML blocks.

Here is the CSS I used to achieve that look:

[css]
body .gform_wrapper #address_block {
	background-color: lightblue;
	padding:16px;
	-moz-border-radius: 10px;
	-webkit-border-radius: 10px;
	border-radius: 10px;
	-khtml-border-radius: 10px;
}
body .gform_wrapper #contact_block {
	margin-top: 20px;
	background-color: pink;
	padding:15px;
	-moz-border-radius: 10px;
	-webkit-border-radius: 10px;
	border-radius: 10px;
	-khtml-border-radius: 10px;
}

The hardest thing to keep straight is breaking out of the list to enable you to add your div and still maintain valid XHTML. Here is an explanation from designer Kevin Flahuat which explains the process http://www.gravityhelp.com/forums/topic/fieldsets#post-17019

It's been requested before, as fieldsets. You're not alone in your desire to have that feature.