Undum : A client side framework for hypertext interactive fiction games
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Pure : A set of small, responsive CSS modules that you can use in every web project.
Bootstrap : Build responsive, mobile-first projects on the web with the world's most popular front-end component library.
Bootstrap is an open source toolkit for ...
LÖVE is a framework for making 2D games in the Lua programming language. LÖVE is totally free, and can be used in anything from friendly open-source hobby projects, to evil, closed-source commercial ones.