## Summary
* In a sample book I loaded, it had 900+ CSS rules, and took up 180kB of
memory loading the cache in
* Looking at the rules, a lot of them were completely useless as we only
ever apply look for 3 kinds of CSS rules:
* `tag`
* `tag.class1`
* `.class1`
* Stripping out CSS rules with descendant, nested, attribute matching,
sibling matching, pseudo element selection (as we never actually read
these from the cache) reduced the rule count down to 200
## Additional Context
* I've left in `.class1.class2` rules for now, even though we
technically can never match on them as they're likely to be addressed
soonest out of the all the CSS expansion
* Because we don't ever delete the CSS cache, users will need to delete
the book cache through the menu in order to get this new logic
* A new PR should be done up to address this - tracked here
https://github.com/crosspoint-reader/crosspoint-reader/issues/1015
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? No
57267f5372