Front-end development is not easy to master. while developing a design developers need to consider different versions of browsers and platforms in their mind, they should know how cross browse works. Responsive design is the latest trend and it is not only difficult to make but also consume so much development time.

However, there are many excellent framework available online that can help you creating interactive websites, I personally like Twitter bootstrap, I have compiled some beautiful frameworks in this article, most of have responsive grid system, using UI component and Javascript plugins

1. GroundworkCSS

GroundworkCSS is a flexible grid system enables you to quickly develop a responsive website for mobile, tablet and desktops. GroundworkCSS is built on powerful CSS preprocessor Sass. Sass is an extension CSS3 and capable of adding nested rules, variables, mixed, selector inheritance and so many different features. Some features are grid, layout, typography, buttons, tiles, tables, forms, icons, social icons, response text, messages, alarms, navigation, labels, tooltips, support for Sass mixed.
website framework for flexible grid system

2. Foundations Framework

Foundation is currently the most advanced framework to develop responsive front-end, it has a lot of template layout, UI components CSS styles, and their own JavaScript plugins. Some of the features aregrid layout templates, icons, fonts, responsive forms, SVG social icons, paging, bread crumbs, sidebar navigation, buttons, fonts, labels, reminders, panel, price lists, progress bars, tables, thumbnails, drop-down button, split buttons, switches, adaptive video, light boxes, drop-down lists, navigation, display modal windows, tabs, tooltips, custom skin form, SCSS mixed.
framework with jQuery and responsive themese

3. HTML Kickstart

Beautiful, UI component rich comes with some useful Javascript plugins and is developer friendly.
JavaScript: menus, tooltips, syntax highlighting, tabs, slide, form validation.

4. Kube CSS framwork

typography, forms, grids, tables, buttons, navigation, icons.

5. Helium – github location
support  SASS & Compass,grid, buttons, layout, tables.

6. Topcat- CSS for fast and clean webb apps

The best part is no Javascript and its pure CSS base framwork
icons, fonts, buttons, bread crumbs, button bar, tables, drop-down list, slide switches, labels, toggle button, select, sliders

7. PureCSS

A set of small, responsive pure CSS modules that you can use in every web project.
skin maker , YU libraries., pure css, no javascript

8. Twitter Bootstrap

Very impressive framework with great features. Some features are grid layout, typography, code, tables, pagination, tabs, badges, thumbnails, reminders, forms, buttons, images, icons, buttons set, navigation, breadcrumbs, progress bar, transition, modal windows, drop-down box, scroll detection, labels, tool tips, pop-up layer, alarm, button accordion, carousel, autocomplete.
 forms, buttons, images, icons, buttons set, navigation, breadcrumbs,