Update Website UI

[yeqbfgxjiq]

Problems

• The current blue/green primary color looks good during the day, but feels a bit harsh at night. Maybe something a little more muted?
• Currently the secondary color in siteConfig.js does not show up.
• There's a lot of white space that can be harsh to look at. It would be great if the white areas were a light grey and the secondary color actually did something. (fwiw it looks great in dark mode tho!)

Site UI Resources

• https://github.com/aragon/aragon-ui/blob/master/src/theme/aragon.json
• https://ui.aragon.org/colors/

[yeqbfgxjiq]

Forked and fixed. Holding off on merging until the coop decides if they want to move forward with this project.