I'm kinda half way through learning CSS myself so I have some questions if you don't mind!
As far as responsive design goes, i'm just starting to touch on that but I'm a little confused. Does every element on the page need a media query or some sort of responsive part to it or can you set the main body to be responsive and everything else follows?
Also with respect to positioning, am I worthwhile learning one method (i.e. CSS Grid) rewlly well, or getting some knowledge of them all (Grid, Flex etc)?
Thanks for any help!
I'm probably not the best person to ask, as I generally try to stay as far away from CSS as I can! But I'll try!
I'm not quite sure what you're asking though. You can (and should) put multiple selectors inside a single media query block, but not every element needs to have its styles changed for different screen widths. The usual workflow is that you start off by making the smallest mobile version of your site without any media queries, then incrementally increase the width, adding media queries and overriding styling where it's required to make the layout optimal at every screen size.
With regards to positioning, you should learn both grid and flexbox layout really well, as they both have different use cases, and they're going to be best practice for the foreseeable future. The bigger question is whether you should learn about laying out pages with floats, and I'm not sure what the answer is there. It's still common to see, but I think its shelf life is really limited, and in a few years, it'll go the way of table-based layouts, and nobody will be expected to know about it.