Flat-UI is a collection of responsive UI toolkits and CSS libraries used to build websites and interactive web components with a flat design aesthetic. It provides a responsive frontend toolkit and a web component library based on the Bootstrap framework to create adaptive layouts.
The library focuses on implementing a consistent flat design through predefined hex color palettes and typography styles. It replaces standard browser elements with customized visual styles to remove skeuomorphic depth.
The toolkit covers a broad range of interface capabilities, including customized form elements such as toggle switches, range sliders, and typeahead search fields. It also provides navigation primitives like pagination and dropdown menus, overlay components for informational tooltips, and stylized video players with custom playback controls.