Medium contrast theme. The most prevalent colours are variants of green, violet, blue, cyan, and magenta.
Oliveira comes in standalone light and dark variants (see further info below).
The font is Iosevka term.
The UI is Atom Material.
Search for oliveira-syntax
in Settings > Install > Themes. Or install it directly using the command:
apm install oliveira-syntax
Project page: https://protesilaos.com/oliveira
Oliveira dark version: https://atom.io/themes/oliveira-dark-syntax
Good catch. Let us know what about this package looks wrong to you, and we'll investigate right away.