All the frameworks bellow will help you develop sites rapidly by eliminating the basic CSS style work. Also, most of them will help you create mobile-versions of your site.
Amazium CSS framework
Amazium is a simple CSS framework for creating responsive web design websites. It uses the 960 Grid grid framework and provides a nice look-and-feel on other HTML elements as well. Amazium is at version 1.0 but its good enough to be used on websites. If you have feedback or any other bugs you can always put your comment here
Gridless CSS framework
This CSS framework is an optionated HTML and CSS3 boilerplate for creating mobile responsive, cross-browser websites that have nice typography. This framework is meant to be a starting point that should be overwritten to suit your projects.
Main features include: Progressive enhancement, mobile first, cross-browser compatible (even IE6/7), CSS normalization instead of CSS reset, nice typography, print styles optimized for performance, optimal caching, HTML5 and CSS3 ready, safe CSS hacks instead of conditional classnames/stylesheets, micro clearfix hack, well-organized folder structure, etc.
Frameless CSS framework
Frameless is another “Responsive web design” framework build to make your life a little bit easier when coding for multiple OS platforms (mobile/desktop/pad). As other grid frameworks recommend you should start with mobile version first and don’t worry about IE6-7.
BlueCSS was design with ease of use and simplicity in mind. This framework was specially made so that you don’t worry about the essential CSS when building your next project. With BlueCSS you can be up and running in less than a minute.
inuit.css combines lot of years of dev tips. To quote its author, inuit.css is plugins, progressive, flexible, mobile, tablet, sensible, extensible, accessible, pragmatic, functional, useful, production-ready and more…
320 and Up css framework
This nice frameworks prevents mobile devices from downloading desktop files by using a tiny screen’s stylesheet as its starting point.
The 1140px CSS Grid System
This framework fits perfectly on a 1280 monitor. On smaller ones, it becomes fluid and adapts to the width of the browser. Beyond a certain point it goes to mobile version which essentially stacks all the columns on tap of each other.
The semantic grid system
Set column and gutter widths, choose the number of columns, and switch between pixels and percentages.
Columnal CSS framework
Columnal CSS grid system is a remix of other grid CSS frameworks but with some custom code thrown in. The elastic grid system is from cssgrid.net, while some code inspiration are taken from 960.gs
Fluid Baseline Grid Framework
This framework was build with typographic standards in mind combining fluid-column layouts, baseline grids, mobile-first responsive design into a nice independent framework. Its packed with CSS normalization, nice typographic standards, common browser inconsistencies and improved usability.
MQFramework CSS Framework
A responsive CSS framework, MQFramework utilises the @media property to allow you to design your sites for browsers of all sizes. Based on a 12 column grid, MQFramework degrades perfectly down to mobile screen sizes.
LESS Framework 4
Less Framework is a CSS grid system for designing adaptive websites. It contains 4 layouts and 3 sets of typography presets, all based on a single grid.