CSS3Designer 2.0 for Mac could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. This software for Mac OS X is a product of eos new media GmbH & Co. KG. We recommend checking the downloaded files with any free antivirus. The software belongs to Design & Photo Tools.
From the developer:
CSS3Designer is a small application which allows you to create CSS3 styles. This application allows you to see a preview of your value adjustments. The app allows you to edit: name, size, opacity, border, margin, etc. This app is very easy to use by any user.
You may want to check out more software for Mac, such as Cuadro or Resize Now, which might be similar to CSS3Designer.