Purr: design pass

[MaggieCabrera]

Purr is a theme that mimics the design of X/Twitter. We should tweak the design before we launch it:

• Improve general spacing and global paddings
• Typography needs a bit more consistency. The single post content is a different font size than the home
• Make sure that the other templates look ok. The theme doesn't have a 404 template
• See if we want to create block patterns for the theme