Bootstrap

Since 1.8.1, we decided to make our themes with Bootstrap as a foundation.

There are a couple of reasons for this:

1. We need a unified API for CSS. Modules and current themes are a motley hodgepodge of class and id names with various colors and layout. By adapting layout around Bootstrap standards, we can agree on how things should work by how they are defined. Changing a class definition will have an expected change.
2. Bootstrap uses responsive design, allowing our themes to degrade based on the user's device.
3. Eventually, we want to ship with a product that allows you to control your site's appearance without having to download a new theme each time. Having a unified CSS standard makes that easier.

As we move towards this goal, old themes will be impacted. So you may need to read our page on Bootstrap Compatibility.