Learn to build a responsive HTML5 and CSS3 website template using FlexboxGrid, a lightweight Flexbox-based grid system. Follow along to create a header, style columns, implement containers, and design various sections including info, image, and footer. Explore inner pages, sub-headers, and contact forms while mastering custom CSS techniques. Dive into responsive design with media queries and discover how to create visually appealing layouts using Flexbox. By the end of this tutorial, gain practical skills in modern web development and responsive design principles.