Progressively enhanced, vanilla everything, Bookmark Landing page

This one tripped me up in places I didn't expect. Notably, pseudo elements and SVGs. I put some details of the specific issues in the readme.

Key problems are:

• Horizontal scrolling is still an issue because of the first pseudo element. I am not sure how I can fix this, or why it is only happening on the first pseudo element and not the second. They are essentially the same element with some extra transitions on the second one. Any advice on this would be appreciated.
• I wanted to inline the SVG images but it caused so many issues that I opted not to in the end, and although not ideal took the performance hit. I had problems with background color, sizing and strange things in Safari - like bits of the SVG missing. Any suggestions on resources, courses or learning materials would be really appreciated.