Learn how to build a responsive website from scratch using HTML and CSS in this comprehensive tutorial video. Focus on creating a navigation bar for the desktop version of the site. Set up a Frontend Mentor project, use Adobe XD for design reference, and create necessary SCSS and JavaScript files. Utilize the Live Sass Compiler VS Code extension for efficient development. Write HTML markup for the header, implement helper classes for navigation styles, and create Sass variables for colors and font sizes. Style the navigation bar, including spacing, hamburger menu, logos, and header links. Design and style a CTA button with linear gradient and hover effects. Implement helper classes for responsive design and create a Sass mixin for breakpoints. Fine-tune header link and logo styles, and add active/hover states with transitions for a polished user interface.