If you have been provided with custom CSS to modify the appearance of a product, it's easy to simply copy / paste this into Rapidweaver.
1. Copy the CSS code you'd like to utilize.
2. Open Rapidweaver and select the page to apply the styling to
3. Select Page Info -> Style -> Header
4. At the lower portion of this pane, choose the CSS tab.
5. Paste your custom CSS into this input