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.
Cloudflare is a web-infrastructure and website-security company, providing content-delivery-network services, DDoS mitigation, Internet security, and distributed domain-name-server services.
Highcharts is a charting library written in pure JavaScript, for adding interactive charts to a website or web application. Highcharts meets accessibility standards and works with Python, Angular, React, iOS, Android, and more.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Unpkg is a content delivery network for everything on npm.