So i've been trying to use more css3 properties for a few reasons(less images = faster load time, ease of making changes, etc).

Whats the best way to go about css3 fallback?

So I deal with a lot of content areas where I have to slice them into 3 sections. Top, a repeating container, and Bottom

HTML Code:
<div id="content-top"></div>

<div id="content">This is where my text goes and the content area grows as large as I need it too</div>

<div id="content-btm"></div>
But with css3 I just need the content area and can make the container, with drop & inner shadows etc.

So is it best to leave content-top & content-btm in my html and not assign them any css unless css3 isn't working in that browser?

Any advice/suggestion will be appreciated.