Bootstrap is a free and open-source CSS framework directed at responsive, mobile-first front-end web development. It contains CSS and JavaScript-based design templates for typography, forms, buttons, navigation, and other interface components.
cdnjs is a free distributed JS library delivery service.
CivicTheme is an open source, inclusive and component-based design system. It was created so governments and corporations can rapidly assemble modern, consistent and compliant digital experiences.
Font Awesome is a font and icon toolkit based on CSS and Less.
Mustache is a web template system.
Popper is a positioning engine, its purpose is to calculate the position of an element to make it possible to position it near a given reference element.