Foundation was made to support as many screen sizes as possible with minimal fuzz and they're using Sass with Compass. They released version 4 about 5 weeks ago

Foundation was made to support as many screen sizes as possible with minimal fuzz and they're using Sass with Compass. They released version 4 about 5 weeks ago and it is mobile-first. See http://foundation.zurb.com/ http://foundation.zurb.com/ .