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.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
MODX (originally MODx) is an open source content management system and web application framework for publishing content on the World Wide Web and intranets.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Open Graph is a protocol that is used to integrate any web page into the social graph.
VK is a Russian online social media and social networking service.
WhatsApp Business is a free to download app available on Android and iPhone using which businesses can connect with their customers.