Copy the config.toml file from the exampleSite directory to your site directory and change it.
favicon.ico: Just put your favicon.ico under the /static directory if you want to change the default favicon.ico.
Front matter: Copy the default.md file from the archetypes directory to your archetypes.
Language: Language files are under /themes/even/data/even/ directory. Create a new directory even under your data directory and copy the default.toml to your /data/even/, and then you can change it if you want.
Theme color: Default | Mint Green | Cobalt Blue | Hot Pink | Dark Violet
You can config it by change the $theme-color-config value in /src/css/_variable.scss.
if you change any file under /src/, you need to rebuild.