Materialize CSS - A modern responsive front-end framework based on Material Design
HTML5 Boilerplate - A rock-solid default for HTML5 awesome.
Foundation - The most advanced responsive front-end framework in the world
HTML KickStart - HTML KickStart is a ultra–lean set of HTML5, CSS, and jQuery (javascript) files, layouts, and elements designed to give you a headstart and save you a lot of hours on your next web project.
Bootstrap - Simple and flexible HTML, CSS, and JS for popular UI components and interactions
HTMLBoilerplates.com - Start your web project by generating and downloading your custom HTML Boilerplate.