This Prism theme based on Theme Gloom from Atom (https://github.com/hejrobin/gloom).
Add gloom-prism.css:
<link rel="stylesheet" href="gloom-prism.css">
Should be something like that:
<!DOCTYPE html>
<html>
<head>
...
<link href="themes/gloom-prism.css" rel="stylesheet" />
</head>
<body>
...
<script src="prism.js"></script>
</body>
</html>
