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.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Leaflet is the open-source JavaScript library for mobile-friendly interactive maps.
Modernizr is a JavaScript library that detects the features available in a user's browser.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
OWL Carousel is an enabled jQuery plugin that lets you create responsive carousel sliders.
RequireJS is a JavaScript library and file loader which manages the dependencies between JavaScript files and in modular programming.
Unpkg is a content delivery network for everything on npm.