This is a color theme for Sublime Text, Atom and VS Code.
The Python source code in the screenshot is highlighted with MagicPython.
In Sublime Text install the Chromodynamics package with "Package Control".
In Atom find the Chromodynamics theme, install it, and enable via
Themes / Syntax Theme.
In VS Code, install the Chromodynamics theme with the Install Extensions command or type ext install magicstack.Chromodynamics in the Quick Open sheet.