Hi there!
My comments below your points:
WHY ** do you only give us width** RANGES ** as breakpoints? Those are “break ranges”. There’s no equivalent in code, as far as I know.**
As CSS developer, that is what I work with all the time. Responsive design reacts to the screen width based on width pixel. For example @media (max-width: 780px) or @media (min-width: 780px) is exactly what is being conveyed here. I love how I can add up to 5 breakpoints ranges for more complex layouts.
Smart CSS tricks help control visuals when someone rotates their screen, and these tricks can be implement using the combination of breakpoints, design, and elements inspector configurations.